Issue n°20 - May 2012
Review of the past and look forward to the future
The IMBER International Project Office (IPO) recently relocated from Brest in France to Bergen in Norway.
This issue of the IMBER Update reflects on IMBER's beginnings in France and the people who were involved in the IPO during its time there, and looks forward to its new home in Norway. There are also several research highlights from members of the French IMBER science community.
How the IPO came to be in France
A brief story of the establishment of the IMBER IPO at the European Institute for Marine Studies (Brest, France)
||During the final meeting of the Joint Global Ocean Flux Study (JGOFS) held in Washington D.C. (U.S.A.), the question of the continuation of the programme was addressed. A Transition Team, chaired by Julie Hall (NIWA, New Zealand), was constituted. This team proposed that a new programme called “OCEANS”, dealing with the impact of global climate change on ocean biogeochemistry and ecosystems and their interactions, be launched as soon as possible. The Science Plan and Implementation Strategy were finalized in 2004. Patrick Monfray, who at the time was Head of the Laboratoire des Sciences du Climat et de l’Environnement (Gif-sur-Yvette, France), was Vice-President of the Task Team. In parallel, Paul Tréguer, Director of the European Institute for Marine Studies (IUEM, Brest, France), who acted as coordinator of the Southern Ocean – JGOFS, was very involved in the coordination of a proposal to garner the efforts of more than 60 institutes throughout Europe to study the impact of global change on ocean biogeochemistry and marine ecosystems. It was conceived as the European contribution to OCEANS and was to be known as EUR-OCEANS. In spring 2004, the European Commission agreed to fund EUR-OCEANS to the tune of 10 M€ from 2005 to 2008. Meanwhile, the IGBP and SCOR project was renamed "IMBER” (Integrated Marine Biogeochemistry and Ecosystem Research). Patrick Monfray, with the support of the Institut National des Sciences de l’Univers (INSU)|
|of the Centre National de la Recherche Scientifique (CNRS), approached Paul Tréguer, to investigate the possibility of his Institute hosting the IMBER International Project Office (IPO). Joining forces, Patrick Monfray and Paul Tréguer convinced the University of Brest, the INSU-CNRS, the Institut de Recherche pour le Développement (IRD), the French Research Institute for Exploration of the Sea (Ifremer) and the Région de Bretagne to make a joint contribution to fund the IMBER IPO. The proposal was well received and the decision to host the IMBER IPO in Brest was agreed to by IGBP and SCOR. The IPO was officially installed at the IUEM on 25 October 2005. Sylvie Roy (Executive Officer), Sophie Beauvais (Deputy Executive Officer) and Elena Fily (Administrative Assistant) were recruited and IMBER was ready to go.|
In the beginning....
||The OCEANS Transition Team was charged with developing a Science Plan for the new IGBP/SCOR project. The members of the transition team were, Julie Hall (Chair), Dennis Hansell (Vice Chair), Patrick Monfray (Vice Chair), Ann Bucklin, Jay Cullen, Wilco Hazeleger, David Hutchins, Arne Kortzinger, Carina Lange, Jack Middelburg, Coleen Moloney, Wajih Naqvi, Raymond Pollard, Hiroaki Saito, Carol Turley and Jing Zhang. Both IGBP and SCOR provided significant support to the Transition Team. To get community input into the Science Plan, the OCEANS Open Science Conference was held in Paris at the International Oceanographic Commission in January 2003. The input from the conference was used by the Transition Team to develop the Science Plan was accepted by IGBP and SCOR and published in 2005. To support the development of IMBER, the National Institute of Water and Atmosphere in New Zealand provided part time secretarial support from late 2003 to June 2004. This position was filled initially by Penny Cooke and then by Claire Hamilton. In June 2004, the IMBER secretariat was moved to the Plymouth Marine Laboratory who supported Claire in her part-time role as secretariat for the project from June 2004 to April 2005. This early support for the development of IMBER was critical to the organisation of the Open Science Conference in Paris and the development of the Science Plan.|
THE IMBER IPO: The making of
In August 2005, I moved to France to become the first Executive Officer of IMBER. My first challenge was to establish the International Project Office (IPO) at the Institut Universitaire Européen de la Mer (IUEM) in Brest, France where the IMBER IPO was to be hosted.
As I was uninitiated with the French administration, I relied heavily on support from Paul Tréguer and the IUEM and l’Université de Bretagne Occidentale (UBO) administrative teams. In September 2005, Elena Fily was recruited to be the Administrative Assistant for the IPO. Her familiarity with the university administrative system was invaluable. She took on the management of the administration of the IPO and international IMBER activities. Elena also became the editor of the IMBER Update newsletter.
In October 2005, we were joined by Sophie Beauvais as Deputy Executive Officer. Sophie had research expertise in the field of biogeochemistry and quickly took responsibility for the communications products. This included developing the IMBER website, producing posters to promote the project at meetings and conferences and the monthly online IMBER e-News bulletin – the 51st edition of which was recently published!
By December that year, the IMBER IPO was fully operational and had actively begun the coordination of projects and promotion of IMBER activities.
IPO staff: Where are they now…
- Although Sylvie Roy returned to Canada in September 2008, she continued to direct the IMBER IPO activities from there until Lisa Madison took over the Executive Officer responsibilities in April 2009. Sylvie is now Program Officer at the Natural Sciences and Engineering Research Council (NSERC) in Ottawa, where she manages a Life Sciences Evaluation Group for the Discovery Grants Program.
Goodbye from our French hosts
IMBER – a greatly valued guest!
In 2005, when, at the invitation of Paul Tréguer, the IMBER IPO was established in Brest, the scientific community had no idea of the impact that its arrival would have. Firstly, it presented a new concept of science management at the European Institute for Marine Studies - based on networking, disrupting our usual work habits and our perception of distance. With IMBER within our walls, the internationalisation of marine science research was suddenly boosted, greatly benefiting the institute. Secondly, IMBER provided the opportunity for friendly and interesting interactions with the Executive Officers, first Sylvie Roy and then Lisa Maddison, both professional and competent individuals with a very high sense of the importance of human relations.
Since 2008 when I took over as leader of the IUEM, the most fruitful interaction between the institute and the IMBER IPO was the collaborative organization of the second summer school dealing with climate change impacts on the marine ecosystem - ClimECO2. The IUEM administrative and scientific teams were superbly coordinated by Sophie Beauvais, the Deputy Executive Officer of the IMBER IPO, who showed an astonishing capacity for work and professional consciousness. Gathering more than 80 participants from 26 countries, ClimECO2 exceeded all expectations, mixing students and young researchers with internationally renown scientists in a resolutely interdisciplinary approach to dealing with climate impacts. More than just a “school”, ClimECO2 provided the opportunity for collaboration and conceptualization in preparing for the future.
More recently, when the Brittany cluster “Europole Mer”, lead by Paul Tréguer, applied to become the French Centre of Excellence - LabexMER - an ambitious international scientific project based in Brest, IMBER provided a strong argument for the capacity of the institute in terms of its international visibility.
IMBER’s leaving is a great loss for the Brest marine scientific cluster. However, I am sure that interactions between us will continue. IMBER has taught us the reality of distance – and in that sense, Bergen is just next door !
Warm thanks to all the people who have been involved in the IMBER IPO since 2005.
Very best wishes for the future，
Thanks to IUEM in Brest - IMBER’s first home
The Institut Universitaire Européen de la Mer (IUEM) hosted the IMBER International Project Office (IPO) during a period that was critical to the development of the IMBER project. The long-term support from the consortium of French funding partners provided both a stable base and the staff and that allowed the IPO to become the core of IMBER. The additional local support from IUEM added a pleasant working environment, with two IMBER offices overlooking the Rade de Brest, assistance with day-to-day activities, and scientific colleagues.
The supportive and collegial environment at IUEM made a valuable contribution to the success of IMBER. It allowed the IPO staff to focus on the coordination and management of IMBER science at national, regional and international levels. Project communication and fund-raising for IMBER events and activities by the IPO, enabled the regional programmes and working groups to focus their resources on science activities. As a result, IMBER science is making contributions in a range of disciplines, the most recent being research at the interface of human and natural systems.
During the seven years at IUEM, the IMBER IPO developed into a mature and well-respected organization within the global environmental change research community. As the IPO moves to its new home at the Institute of Marine Research (IMR) in Bergen, Norway, there is a tinge of sadness at leaving IUEM. However, science (and IMBER) is an international endeavour and connections made at IUEM will continue through the IPO in Bergen. So, as the IMBER science community looks forward to a new home at IMR, we will also look back at the time when IUEM and the consortium of French funding partners paved the way for IMBER to continue to move forward.
Merci beaucoup pour votre engagement à nos cotés ainsi que pour lesoutien apporté au cours de ces sept années.
Eileen E. Hofmann
Chair, IMBER Scientific Steering Committee
Ocean Carbon Sink within a Strong Bloom Area in the Subantarctic Zone
Anna Lourantou and Nicolas Metzl
LOCEAN, IPSL, CNRS, Université Pierre et Marie Curie, 4, Place Jussieu, 75252, Paris
The Subantarctic Zone (35–50°S), a key area for mode water formation and anthropogenic carbon isolation (Sabine et al. 2004), constitutes one of the most efficient atmospheric CO2 sinks (Metzl et al. 1999; Takahashi et al. 2009). This sink is partly linked with extended phytoplankton blooms downstream of the subantarctic islands which contrasts the High Nutrient Low Chlorophyll (HNLC) character of Southern Ocean waters (Bakker et al. 2007; Jouandet et al. 2008).
In a recent study (Lourantou and Metzl 2011) we examined the ‘island mass effect’ downstream of the NE Kerguelen Plateau and linked it for the first time with the carbon cycle. Particular interest was paid to the role of local bathymetry and current patterns associated with the influence of the Subantarctic Front (SAF) towards the carbon feedback. A seasonal to decadal air-sea CO2 fluxes monitoring within this bloom area, along the track between Kerguelen (49°15′S; 69°35′E) and Amsterdam (37°49′S; 77°33′E) islands was conducted (Fig. 1). Data from 17 French cruises (Minerve and OISO cruises onboard the Marion-Dufresne) undertaken from 1991 to 2011 were used, the majority of which was retrieved from the SOCAT (Surface Ocean CO2 Atlas) database (Pfeil et al. (2012); http://www.socat.info).
For all cruises, the properties of surface waters north and south of the SAF are different (Fig. 2). This clearly shows the biological imprint upon the spatial distribution of fCO2 (f for fugacity), while the positioning and intensity of the bloom are directed by bathymetrical and physical properties. Our findings suggest that Fe is diffused from the shallow topography of Kerguelen Plateau to the surface and is carried away by the currents in a NE direction, generating seasonal blooms and CO2 drawdown (fCO2<200µatm). The positioning of the SAF coupled with the Antarctic Circumpolar Current (ACC, strength of up to 1.6m s-1) block its diffusion further northwards.
The air-sea CO2 fluxes in surface waters figure a net annual sink of CO2 for both parts separated by the SAF, the integrated annual flux found for the northern part being three times more important than the southern one. When compared with the updated air-sea CO2 fluxes climatology (http://www.ldeo. columbia.edu/res/pi/CO2/carbondioxide/pages/air_sea_flux_2010.html), the northern part reveals a similar order of magnitude, but here the southern sink is six times more important. Therefore, before proceeding with extrapolations of air-sea CO2 fluxes calculations in space and time, these distinct zones should be considered separately.
On a decadal scale, as far as the fate of the carbon sink is concerned for both distinct regions, summer reveals clearly different tendencies: north of the SAF the sink increases, while south of the SAF, in the bloom area, the ocean CO2 sink declines. We suggest this decline is due to a weaker water mixing, induced by weaker wind speeds. This would also imply a reduced Fe alimentation from the plateau, which curtails the productivity of the waters.
This study will provide further constraints on modelling or observations over more extended areas that speculate a decreasing Southern Ocean sink pattern (Le Quéré et al. 2007; Metzl 2009). It also constitutes, a reference study for the outputs of the KEOPS2 cruise conducted in austral spring 2011, which deals with the natural Fe fertilization effect in this area.
We speculate towards an extension of such application to other ocean basins, downstream of other island systems. Further research on such complex areas, including the ensemble of inorganic carbon systems with implications for ocean acidification, upstream from repercussions to ecosystems, is also in progress (Lourantou et al. 2012).
We thank IMBER (for participation in the ClimECO2 summer school: Oceans, marine ecosystems and society facing climate change. A multidisciplinary approach, Brest, France), IMBER, SOLAS and IOCCP (for participation at the conference: The ocean carbon cycle at a time of change: Synthesis and vulnerabilities, UNESCO, Paris, France), INSU/CNRS (LEFE project Flamenco2), IPEV/IPSL/INSU, the captains and crews of the R.V. Marion Dufresne, and A. Kartavtseff, M. Ramonet, for ADCP and atmospheric 2011 CO2 data, respectively.
Bakker D.C.E., M.C. Nielsdóttir, P.J. Morris, H.J. Venables and A.J. Watson (2007), The island mass effect and biological carbon uptake for the subantarctic Crozet Archipelago, Deep Sea Res., Part II, 54 (18-20), 2174-2190.
Jouandet M.-P., S. Blain, N. Metzl, C. Brunet, T.W Trull and I. Obernosterer (2008), A seasonal carbon budget for a naturally iron-fertilized bloom over the Kerguelen Plateau in the Southern Ocean, Deep Sea Res., Part II, 55 (5-7), 856-867.
Le Quéré C., C. Rödenbeck, E.T. Buitenhuis, T.J. Conway, R. Langenfelds, A. Gomez, C. Labuschagne, M. Ramonet, T. Nakazawa, N. Metzl, N. Gillett and M. Heimann (2007), Saturation of the Southern Ocean CO2 Sink Due to Recent Climate Change, Science 316 (5832), 1735-1738.
Lourantou A. and N. Metzl (2011), Decadal evolution of carbon sink within a strong bloom area in the subantarctic zone, Geophysical Research Letters 38, L23608, 7 pp., doi:10.1029/2011GL049614.
Lourantou A., C. Lo Monaco, C. Brunet and N. Metzl (2012), Seasonal to decadal pH and fCO2 changes in the subtropical, sub-antarctic and polar waters of the SW Indian Ocean, Geophysical Research Abstracts 14, EGU2012-12252, EGU General Assembly 2012.
Metzl N., B. Tilbrook and A. Poisson (1999), The annual fCO2 cycle and the air–sea CO2 flux in the sub-Antarctic Ocean, Tellus B 51(4), 849-861.
Metzl N. (2009), Decadal increase of oceanic carbon dioxide in Southern Indian Ocean surface waters (1991–2007), Deep Sea Res., Part II, 56(8-10),607-619.
Park, Y.-H., N. Gasco, and G. Duhamel (2008), Slope currents around the Kerguelen Islands from demersal longline fishing records, Geophys. Res. Lett., 35, L09604, doi:10.1029/2008GL033660.
Pfeil, G.B, Olsen, A., Bakker, D.CE, (in prep.), A uniform, quality controlled, Surface Ocean CO2 Atlas (SOCAT), ESSD.
Sabine, C.L., Feely, R.A., Gruber, N., Key, R.M., Lee, K., Bullister, J.L., Wanninkhof, R., Wong, C.S., Wallace, D.W.R., Tilbrook, B., Millero, F.J., Peng, T.H., Kozyr, A., Ono, T., Rios, A.F., (2004), The oceanic sink for anthropogenic CO2, Science 305 (5682), 367-371.
Takahashi T., Sutherland, S.C., Wanninkhof, R., Sweeney, C., Feely, R.A., Chipman, D.W., Hales, B., Friederich, G., Chavez, F., Sabine, C., Watson, A., Bakker, D.C.E., Schuster, U., Metzl, N., Yoshikawa-Inoue, H., Ishii, M., Midorikawa, T., Nojiri, Y., Körtzinger, A., Steinhoff, T., Hoppema, M., Olafsson, J., Arnarson, T.S., Tilbrook, B., Johannessen, T., Olsen, A., Bellerby, R., Wong, C.S., Delille, B., Bates, N.R. de Baar H.J.W., (2009), Climatological mean and decadal change in surface ocean pCO2, and net sea-air CO2 flux over the global oceans, Deep-Sea Research part II 56(8-10), 554-577.
Impact of Ocean Acidification on Mediterranean Coralline Algae
Sophie Martin, Station Biologique de Roscoff, France (Sophie.Martin@sb-roscoff.fr)
CNRS, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Place Georges Teissier, 29682 Roscoff Cedex, France ; Université Pierre et Marie Curie, Paris VI, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Place Georges Teissier, 29682 Roscoff Cedex, France.
Jason Hall-Spencer, Marine Biology and Ecology Research Centre, School of Marine Sciences, Plymouth University.
Jean-Pierre Gattuso, Laboratoire d’Océanographie de Villefranche, France
CNRS-INSU, Laboratoire d’Océanographie de Villefranche-sur-Mer, BP 28, 06234 Villefranche-sur-Mer Cedex, France ; Université Pierre et Marie Curie, Paris VI, Observatoire Océanologique de Villefranche, 06230 Villefranche-sur-Mer Cedex, France.
Coralline algae are a major calcifying component of most Mediterranean benthic coastal ecosystems. They are of particular ecological importance, inducing settlement and recruitment of numerous invertebrates and providing habitats for a high diversity of associated organisms. They are also of significant importance in the carbon and carbonate cycles of shallow coastal ecosystems, being major contributors to CO2 fluxes through high community CaCO3 production and dissolution. However, coralline algae are among the calcifying organisms that appear to be the most sensitive to ocean acidification due to the solubility of their high magnesium calcite skeletons. We investigated the effects of ocean acidification on coralline algae both through in situ observations in a volcanic CO2 vent area off Ischia (Italy) and through a long-term (one-year) mesocosm experiment combining the effects of elevated pCO2 (lowered pH) and elevated temperature. We focused our work on (i) epiphytic crustose coralline algae in Posidonia oceanica meadows, where coralline algae are the dominant contributors to calcium carbonate mass on seagrass blades and (ii) the crustose coralline alga Lithophyllum cabiochae, which is one of the main calcareouscomponents of coralligenous communities in the Mediterranean Sea. We observed that coralline algae were absent at pHT 7.7 (pH on the total scale) in naturally acidified seawater where other calcifiers were living (Fig. 3). We showed a strong combined effect of elevated pCO2 and temperature on L. cabiochae with a decrease in calcification in summer and an increase in mortality and tissue damage under elevated pCO2 (700 µatm, pHT 7.9) and elevated temperature (+3°C, Fig. 4). Our findings suggest that the degree of ocean acidification and global warming expected over the next 100 years may have major consequences for the biodiversity and biogeochemistry of coastal ecosystems dominated by coralline algae.
This work contributes to the EU `Mediterranean Sea Acidification under a changing climate' project (MedSeA; grant agreement 265103) and the European Project on Ocean Acidification (EPOCA; grant agreement 211384).
S. Martin, J.-P. Gattuso (2009) Response of Mediterranean coralline algae to ocean acidification and elevated temperature. Global Change Biology, 15, 2089-2100.
S. Martin, R. Rodolfo-Metalpa, E. Ransome, S. Rowley, M.-C. Buia, J.-P. Gattuso, J.M. Hall-Spencer (2008) Effects of naturally acidified seawater on seagrass calcareous epibionts. Biology Letters, 4, 689-692.
J.M Hall-Spencer, R. Rodolfo-Metalpa, S. Martin, E. Ransome, M. Fine, S.M. Turner, S.J. Rowley, D. Tedesco, M.-C. Buia (2008) Volcanic carbon dioxide vents show ecosystem effects of ocean acidification. Nature, 454, 96-99.
OCVR : Ocean Carbon Variational Re-analyzer - System : A twenty year global re-analysis of sea surface carbon partial pressure from satellite, in-situ measurements and model outputs
A. Kane1, P. Peylin3, P. Rayner1,2
1- CLIMMOD ENGINERING, Cité scientifique d'Orsay, France (Abdou.Kane@climmod.com)
2 - School of Earth Sciences, University of Melbourne, 3010, Vic, Australia
3- Laboratoire des Sciences du Climat et de l’Environnement CEA/CNRS/UVSQ - France
Introduction: The issues of oceanic carbon fluxes
The intensification of climate change has resulted in very active research and development in modelling and observation of the mechanisms involved, especially the climate impact of emissions of greenhouse gases caused by human activity. In this context the ocean plays a crucial role as it contributes to the uptake of about a quarter to a third of the anthropogenic emissions with significant year to year variations (Sabine et al., 2004). However, there is still large uncertainty regarding carbon uptake and storage of anthropogenic CO2 at many space and time scales. This is because the amount of carbon accumulated in the oceans since the beginning of the industrial era is roughly 3% of the surface ocean content, making it difficult to extract the anthropogenic signal from natural variability.
Importance of the ocean surface carbon dioxide partial pressure (PCO2sw)
The air-sea CO2 flux is typically controlled by two terms embedded in the formula: F = (k α) . ΔpCO2 where k is the piston velocity, α is the solubility (Weiss, 1974) and ΔpCO2 the difference between the pCO2 in surface seawater and that in the overlying air. ΔpCO2 represents the thermodynamic driving potential for the exchange flux at the sea-air interface. Uncertainties in the air-sea CO2 flux come not only from the gas exchange coefficient, but also from the ΔpCO2 and are mainly due to the poorly constrained estimates of the sea surface pCO2. Indeed the seasonal and geographical variation of surface water pCO2 is much greater (from 150 to 750 atm) than that of the atmosphere, which varies from 20 atm to around 370 atm in remote uncontaminated marine air (Feely et al., 2001).
OCVR - System: an innovative tool to improve pCO2sw estimation
Ocean pCO2 time series are one of the most valuable tools to observe trends of carbon fluxes. These analyses are limited by the coverage of measurements (less than 5% at 2° and monthly resolution over the last 20 years). The development of satellite measurements that provide very large volumes of data (weekly) and high resolution (less than 1°) provides a solution to this problem. However, the fluxes can only be obtained with indirect methods based either on numerical modelling or from robust algorithms using observable drivers. The OCVR system belongs to this latter family.
OCVR is a neural network framework developed by CLIMMOD within the CARBONES-EU FP7 project (see Fig. 5). As input variables, it uses observations from satellites (e.g. surface chlorophyll, sea surface temperature), in-situ and model outputs (e.g. temperature, salinity, mixed layer depth) that control to first-order the surface ocean pCO2. A variational data assimilation scheme efficiently incorporates new sets of pCO2 observations (trend and seasonal adjustments) and takes into account extreme events like El Niño. The system then uses supplied atmospheric CO2 concentration to calculate air-sea flux according to a selectable exchange parameterization (e.g. Wanninkhof, 1992; Nightingale, 2000; Takahashi, 2009). The results obtained with the OCVR-system are illustrated as global maps (see Fig. 6) and ocean time series (see Fig. 7).
The OCVR system enables, for the first time, a reanalysis of 20 years of gridded air-sea pCO2 and fluxes (2° x 2°, monthly), based on raw pCO2sw data and model/satellite ocean surface fields. This database will soon be made available to the scientific community and described in a scientific paper currently in preparation. Finally, the system will be enhanced to propagate the errors associated with the input fields in order to derived uncertainty for the pCO2 and flux estimates.
Beyond these aspects, the tool can be used to address several more specific issues such as the contribution of coastal regions to the ocean carbon balance. The encapsulation of the system allows it to be easily modulated and adapted to specific areas of the ocean with high resolutions using satellite data inputs (e.g. diurnal variation). It may also be coupled to an operational forecast system, that can supply the needed inputs to simulate real time air-sea carbon exchanges.
Acknowledgments: Z. Poussi, T. Lauvaux, A. Tagliabue, C. Moulin, L. Bopp, J. Orr, N. Metzl, N. Gruber, K. Steinkamp.
Institutions: European Union, NASA, Mercator Ocean.
Feely R A, Sabine C L, Takahashi T, Wanninkhof R (2001) Uptake and storage of carbon dioxide in the oceans: The global CO2 survey Oceanography 14(4) 18–32.
Nightingale P D, Malin G, Law C S, Watson A J, Liss P S, Liddicoat M I, Boutin J, Upsill-Goddard R C (2000) In situ evaluation of air-sea gas exchange parameterizations using novel conservative and volatile tracers. Glob. Biogeochem Cycles 14 373–387.
Sabine, C L, Feely R A, Gruber N, Key R M, Lee K, Bullister J L, Wanninkhof R, Wong C S, Wallace D W R, Tilbrook B, Millero F J, Peng T-H, Kozyr A, Ono T, Rios A F (2004) The oceanic sink for anthropogenic CO2. Science 305 (5682), 367-371.
Takahashi T, Stewart ?, Sutherland C, Wanninkhof R, Sweeney C, Feely R A, Chipman D W, Hales B, Friederich G, Chavez F, Sabine C, Watson A, Bakker D C E, Schuster U, Metzl N, Yoshikawa-Inoue H, Ishii M, Midorikawa T, Nojiri Y, Körtzinger A, Steinhoff T et al. Corrigendum to “Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans” Deep Sea Research II 56 (2009) 554–577.
Wanninkhof R (1992) Relationship between wind speed and gas exchange. J. Geophys. Res. 97 7373–7382.
A global estimation of the nitrous oxide inventory in the ocean
Jorge Martínez-Rey, Marion Gehlen and Laurent Bopp: Laboratoire des Sciences du Climat et de l’Environnement, France
Alessandro Tagliabue: Southern Ocean Carbon & Climate Observatory, South Africa
Nitrous oxide (N2O) is a powerful greenhouse gas with a significant impact not only in terms of radiative forcing but also on ozone (O3) depletion in the upper layers of the atmosphere. N2O sea-to-air flux in the ocean is in the order of magnitude of Tg of N2O per year, the same as that from anthropogenic activities (Denman et al., 2007). As a consequence, both the oceanographic observational and modelling communities have focused on developing parameterizations and methods to make accurate estimations of the global inventory and sea-to-air fluxes of N2O in the ocean.
N2O is a by-product of two different biogeochemical processes within the oceanic nitrogen cycle, namely nitrification and denitrification. In both cases N2O production and oxygen (O2) consumption are highly correlated, a relation shown from measurements since the 1980s and 1990s. Based on these observations, some authors have developed basic parameterizations, where N2O production is proportional to Apparent Oxygen Utilization (AOU), plus additional terms depending on various factors such as temperature (Butler et al., 1989), depth (Suntharalingam and Sarmiento, 2000) or O2 concentration (Nevison et al., 2003, see Equation 1). Considering temperature, salinity and oxygen from the World Ocean Atlas 2005 (Garcia et al., 2006), it is possible to estimate the N2O inventory in the ocean at a global scale (Fig. 8). N2O is mainly produced in the Eastern Equatorial Pacific, North Pacific and Northern Indian Ocean, especially in the Arabian Sea and Bay of Bengal. These regions, where concentrations of N2O are higher, correspond either to oceanic hypoxic conditions (O2 concentration below 60 M/L) or to the so-called Oxygen Minimum Zones (OMZ), where O2 concetration is less than 5 M/L.
Here we apply the same N2O parameterization to recent model simulations from the Coupled Model Intercomparison Project 5 (CMIP5), where we considered the HadGEM2, MPI-ESM, IPSL-CM5-LR and IPSL-CM5-MR models. This enables us not only to make estimations on the N2O inventory, but also to define the uncertainties of our current capabilities, based on the different parameterizations available and on the suite of biogeochemical models available.
Little variation is seen among the different parameterizations, tested on the World Ocean Atlas 2005 data for the upper 1500m along low latitudes, from 40S to 60N. Despite the fact that the N2O parameterizations show different yields for N2O production, an overall estimation differs only by about 10% of the average value of 274 Tg of N2O.
When we compare this estimate based on the World Ocean Atlas 2005 to the CMIP5 models we find that the oceanic N2O inventory is clearly underestimated in all the models (IPSL-CM5-MR N2O inventory is shown in Fig. 8), with an average of 220 Tg of N2O. There is also a wide range of values for the oceanic N2O inventory among the models - from 193 to 263 Tg of N2O (see Fig. 9). The reason for this can be found in the original assumption made on the N2O parameterization, i.e., the oxygen consumption. N2O relies on an adequate and realistic representation of the oxygen fields from the models. Excess oxygen and high sensitivity to remineralization processes within the models play a critical role on each model's performance.
However, all the models show a similar response when a future scenario is considered. Figure 9 also shows the N2O estimations in 2100 when the same RCP8.5 (the most dramatic Representative Concentration Pathway in terms of higher CO2 atmospheric concentration) is applied as external forcing to all the models. The expected future deoxygenation leads to an increase of up to 8 Tg of N2O on average at a global scale. Figure 10 shows the particular change in N2O for the IPSL-CM5-MR model in the future. This change is driven basically by the decreased concentration of O2 in the Pacific, and the enhanced production of N2O both in the North and Eastern Equatorial Pacific.
As an overall conclusion, despite the fact that discrepancies on modelled O2 in the state-of-the-art biogeochemical models do hamper the present estimation of the oceanic N2O inventory, the future projections required for climate change impact assesments show similar incresing trends in marine N2O.
IMBER endorsed projects
PRISM-RS: Processes Regulating Iron Supply at the Mesoscale in the Ross Sea (PRISM-RS)
Dennis J. McGillicuddy, Jr., Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Eileen Hofmann, Mike Dinniman,John Klinck, Peter Sedwick, Old Dominion University, Norfolk, VA, USA
Walker Smith, Virginia Institute of Marine Science, Gloucester Point, VA, USA
Blair Greenan, Bedford Institute of Oceanography, Dartmouth NS, Canada
Thomas Bibby, National Oceanography Centre, Southampton, UK
Corresponding author: Dennis J. McGillicuddy, Jr.,
Tel.: + 1-508-289-2683; Fax: + 1-508-457-2194; Email address: email@example.com
The Ross Sea continental shelf is the single most productive area in the Southern Ocean, and may comprise a significant but unaccounted for oceanic CO2 sink, largely driven by phytoplankton production. However, the processes that control the magnitude of primary production in this region are not well understood. During summer, an observed abundance of macronutrients and scarcity of dissolved iron are consistent with iron limitation of phytoplankton growth in the Ross Sea polynya, as is further suggested by shipboard bioassay experiments. Field observations and model simulations indicate four potential sources of dissolved iron to surface waters of the Ross Sea: (H1) circumpolar deep water intruding from the shelf edge; (H2) sediments on shallow banks and nearshore areas; (H3) melting sea ice around the perimeter of the polynya; and (H4) glacial meltwater from the Ross Ice Shelf. These potential iron sources are isolated, either laterally or vertically, from the surface waters of the Ross Sea for much of the growing season. We hypothesize that hydrodynamic transport via mesoscale currents, fronts, and eddies facilitate the supply of dissolved iron from these four sources to the surface waters of the Ross Sea polynya. Our cruise plan was designed to accomplish two distinct objectives: (A) regional-scale, high-resolution transects to characterize the hypothesized source regions of iron, and (B) mini-process studies to examine selected mesoscale features in detail.
Voyage #12-01 of the RVIB Nathaniel B. Palmer was a 49 day journey from Punta Arenas Chile to McMurdo Station, Antarctica.Shortly after departure on 24 December 2011, we took the opportunity to test two of our towed instrument platforms, the Moving Vessel Profiler (MVP) and the Video Plankton Recorder (VPR). These systems were then stowed away for the transit to the Ross Sea. In transit, we began to address PRISM objectives with an opportunistic process study in and around a band of sea ice in the Antarctic Circumpolar Current (H3). We entered the eastern Ross Sea on January 9, and with the aid of a recently acquired MODIS image sampled two eddies. Shortly after beginning a detailed survey of Eddy 2, we broke off from science operations to respond to a distress call from F/V Jung Woo 2. The rescue mission was completed on January 11 with the evacuation of seven injured fishermen to McMurdo Station. Science operations were recommenced in the Western Ross Sea, starting with a zonal transect at 76° 40’ followed by detailed studies of a cyclonic eddy (including deployment of SeaHorse, a profiling instrument package) and the frontal region between high- and low-biomass areas of the zonal transect (H3). We then proceeded to Ross Bank for surveys and deployment of the SeaHorse in a moored configuration (H2). Next on our agenda was the Ross Ice Shelf, where we sampled Ice Shelf Water and a cyclonic eddy moving northward from the ice edge (H4). From there we transited back to Ross Bank for recovery of the SeaHorse and then proceeded to Joides Trough to sample Modified Circumpolar Deep Water coming up onto the shelf (H1). The last phase of the cruise, we revisited the Western Ross Sea with re-occupation of the 76° 40’ line, study of an eddy near the ice edge, sampling of a suspected hydrothermal vent site near Franklin Island, a north-south transect along 169°E, detailed survey of a frontal region between 169°E and 170°E, and an extension of the 76° 40’ line (actually at 76° 45’) into the far western Ross Sea previously covered with ice (H2,H3). A cruise blog aimed toward middle-school students is available at http://www.steminaction.org/blog/ .
PRISM-RS is supported by the United States Antarctic Program of the National Science Foundation.
COMITE:Coastal Ocean MIcrobial plankton and Temperature
Xosé Anxelu G. Morán (principal investigator), Instituto Español de Oceanografía, Centro Oceanográfico de Xixón, Asturies, Spain
The main aim of COMITE is to predict the effects of global warming on the structure and functioning of planktonic microbial communities in the coastal ocean. To this end, retrospective analysis of a decade-long time-series in the southern Bay of Biscay (NE Atlantic) continental shelf will be combined with temperature perturbation experiments over two years to test the hypothesis that the role of bacteria will be enhanced in warmer waters.
Marine microbes and temperature
Highly diverse, both phylogenetically and metabolically, heterotrophic prokaryotes (hereafter “bacteria” given the low contribution of archea in surface waters (Karner et al. 2001, Alonso-Sáez et al. 2007b) represent the highest living biomass in the ocean and lie at the core of biogeochemical processes mediated by planktonic communities (Azam and Malfatti 2007) by leading the transformation of dissolved organic matter (DOM). The simultaneous function of bacteria as a sink and a source of CO2 (Ducklow et al. 1986) and the relative importance of both processes in a changing world are of crucial importance for the future role of the ocean in response to anthropogenic alterations.
Temperature is a fundamental variable affecting life through its direct effect on biological rates by enhancing enzymatic reactions. A holistic description of the temperature-dependence of metabolic rates and how they control ecological processes was formulated as the metabolic theory of ecology (MTE, Brown et al. 2004). The MTE has only begun to be applied to oceanic ecosystems (Duarte 2007) to derive relationships between phytoplankton abundance, cell-size, biomass and primary productivity (Belgrano et al. 2002, Li et al. 2006, Morán et al. 2010b) and make predictions about the metabolic balance in a warming world (López-Urrutia et al. 2006). The carrying capacity or equilibrium number of individuals in an ecoystem is proportional to the amount of resources, and is inversely related to temperature, i.e. a higher temperature will result in a lower abundance of organisms because energy and matter flow at a higher rate (Savage et al. 2004). The prediction that under an energetic equivalence scenario plankton biomass will decrease with rising temperatures has been confirmed by data on phytoplankton biomass (Fig. 13, Li and Harrison 2008, Morán et al. 2010b). The MTE makes an interesting distinction between autotrophs and heterotrophs, with lower activation energies characterizing photosynthesis (~0.32 eV) compared with those for general metabolism or heterotrophic respiration (~0.65 eV). According to this theoretical framework, the decrease in bacterial biomass with temperature should even exceed that observed for phytoplankton. However, most of the evidence available suggests the opposite: bacteria are usually more abundant in warmer conditions (Li 1998, Steinberg et al. 2001, Alonso-Sáez et al. 2008b). Sometimes this increase tends to level off or decrease at some threshold, but the covariation between bacterial abundance and growth rates, both increasing to some degree with increasing temperature (Fig. 14, Steinberg et al. 2001), is thus paradoxical. A hypothesis that may partially explain this discrepancy is that the availability of organic substrates for bacteria increases with temperature, overcoming nutrient limitation. The difficulty to separate direct effects of temperature from other covarying environmental factors, such as nutrient availabilitly, is a major drawback. In most temperate ecosystems, inorganic nutrient concentrations become limiting during summer stratification resulting in a decrease of primary production providing the basis for bacterial growth. However, bacteria may be relieved of their direct trophic dependence on phytoplankton and rely on allochthonous or previously accumulated DOC (Serret et al. 1999, Morán et al. 2010a, Teira et al. 2009), which would also explain why bacterial numbers keep going up with increasing temperature well after the annual peak in phytoplankton (Steinberg et al. 2001, Alonso-Sáez et al. 2008).
Another usually overlooked ecological rule in microbial plankton studies deals with temperature-size relationships, which for the sake of simplicity will be referred to as the temperature-size rule (TSR, Atkinson et al. 2003). Higher temperatures are phenotypically associated with lower individual sizes (Fig. 15B), as shown for the cyanobacteria Synechococcus and Prochlorococcus in Morán et al. (2010b). As smaller organisms have lower energetic requirements, a higher abundance of bacterial cells would be expected with increasing temperature, similar to the increase in total (Li et al. 2006) or small phytoplankton (Fig. 15A) cell numbers. However, from cyanobacteria to the greatest diatom chains, phytoplankton span over 8 orders of magnitude while bacterial sizes are in a much more constrained range (0.02-0.2 µm3). Although there is some evidence that even in this narrow range bacterial size may respond to temperature in the same fashion (Daufresne et al. 2009, Straza et al. 2009), this hypothesis would fail to fully explain why total bacterial biomass tends to increase rather than decrease with temperature.
One of the most conspicuous effects of the accumulation of anthropogenic greenhouse gases in the atmosphere is global warming. Projections of mean atmospheric temperature rises between 1 and 6ºC by the end of the 21st century (IPCC 2007) will have an immediate effect in the surface ocean, which indeed has warmed up by a mean 0.1ºC over the last 40 years, with predicted accelerations ending up in 2-3ºC increases over current temperatures in a few decades (Boyd and Doney 2002). The effect of ocean warming is extremely difficult to evaluate due to interactions and feedback processes, and it will probably take place at a sufficiently slow pace so as to allow adaptations within extant planktonic communities or replacements of species. However, even under the mildest climatic scenario, the whole pelagic ecosystem will be affected either by changes in productivity (Frederiksen et al. 2006) or shifts in the timing of ecological events and disruption of trophic links (Edwards and Richardson 2004). Besides the aforementioned direct impacts on metabolism, ocean warming will likely result in stronger stratification (Sarmiento et al. 2004) and may also affect the formation of phytoplankton aggregates after blooms and their subsequent degradation by bacteria (Piontek et al. 2009). Boyd and Doney (2002) have projected regional differences in both the mixed layer depth and upwelling phenomena by 2060-2070. In the COMITE study region, the southern Bay of Biscay, current time-series data contradict the increase in upwelling events predicted by those authors (Llope et al. 2007, Pérez et al. 2010). Longer periods of nutrient-depletion associated with changes in stratification and mixed layer depth will favour small phytoplankton at the expense of diatoms (Falkowski and Oliver 2007). This pressure will add to the direct effect of increased temperatures on the size-distribution of phytoplankton and the increasing importance of tiny primary producers (Morán et al. 2010b). All in all, the efficiency of the biological pump will likely be reduced, leaving the potential for an increase of the flow of carbon through heterotrophic bacteria (Kirchman et al. 2009, Wohlers et al. 2009). As bacteria are one of the most important, if not the most important group, contributing to community respiration (Robinson 2008), an increase in their biomass and metabolic rates (López-Urrutia and Morán 2007, Vázquez-Domínguez et al. 2007) will contribute to a positive carbon-climate feedback (emission of CO2). In spite of the evidence gathered so far, longer (>40 years) planktonic time-series are needed before conclusive statements on the effect of anthropogenic climate change vs. natural variability can be reached (Henson et al. 2010). Perturbation experiments can provide testable hypotheses on the directions and magnitudes of change (Boyd and Doney 2002).
The huge densities (typically close to 106 cells per mL), relatively high growth rates (0.1-1 d-1) and large surface to volume ratios of coastal bacteria make them potentially highly sensitive to environmental perturbations. The underlying assumption of COMITE is that heterotrophic bacterial communities will be key indicators of climatic variability. Although the response of planktonic communities to global change has received the attention of scientists from different disciplines (e.g. Bopp et al. 2001; Richardson and Schoeman 2004, Behrenfeld et al. 2006, López-Urrutia et al. 2006), few studies have specifically addressed the response of heterotrophic bacterioplankton (Kirchman et al. 2009). In this project we will focus on temperature, and try to elucidate the direct responses of a wide range of microbial plankton variables. A better understanding of the ecological relationships between bacterial cell size, abundance, biomass, growth rates and transformations of organic carbon modulated by temperature will help us make better predictions about how bacterial carbon cycling might change in the future. The discrepancy between the predictions of MTE and those of other analyses that converge in foreseeing a greater, more dominant role of bacteria in a warmer ocean (Kirchman et al. 2009, Wohlers et al. 2009, Sarmento et al. 2010) must be resolved before any serious attempt to further our understanding of the response of oceanic microbes to climate change.
Will there be more or less bacteria in a warmer ocean?
Two main hypotheses, apparently mutually exclusive, will be tested. The first, based on cross-region and time-series observations, the temperature size rule and most foreseen physico-chemical and biological changes in the upper ocean is that heterotrophic bacteria will increase their abundance and biogeochemical role with increasing temperatures over the next decades. The second hypothesis, based on the claimed universality of the metabolic theory of ecology (MTE) is that enhanced bacterial metabolism will result in lower biomass at higher temperatures. As both hypotheses cannot be true simultaneously unless we are missing important factors most likely related to the enormous bacterial phylogenetic and physiological diversity, other partial hypotheses of COMITE that will help solve this discrepancy include:
Within the goal of building a predictive, testable model on the effects of realistic temperature rises on the biogeochemical role of oceanic bacteria, the objectives of COMITE are:
1. To analyze 10 years of microbial observations in the southern Bay of Biscay continental shelf with the aim of finding macro-ecological patterns of bacterial variables (abundance, size and other single-cell properties) related to temperature and other environmental variables.
2. To describe the annual variability of the temperature dependence of heterotrophic bacterioplankton including effects on growth rates of selected phylogenetic and physiological bacterial groups.
3. To assess the role of bottom-up and top-down controls on the seasonal patterns of bacterial abundance, cell size and biomass.
4. To gain insight into the changes in microbial carbon fluxes with temperature by conducting experiments in four ecologically significant periods of the seasonal cycle.
All new data in COMITE will be collected within the planktonic time-series off Gijón/Xixón of the Spanish Institute of Oceanography (IEO) RADIALES program (http://www.seriestemporales-ieo.com). The effects of future warming on the ecology and biogeochemical role of temperate coastal microbial assemblages will be addressed through three different activities (Fig. 16):
Activitiy 1. Retrospective analysis of the linkages between temperature, other environmental drivers and bacterial community structure and size-abundance relationships of 10 years of observations in the Gijón/Xixón coastal oceanographic time-series (April 2002- March 2012).
With a decade just completed (Fig. 16), the temporal variability at the three continental shelf stations of the RADIALES program (Calvo-Díaz and Morán 2006) will be analyzed in order to extract the seasonal and long-term components by conventional and non-linear time series analysis.
Activitiy 2. Temperature response of selected physiological and phylogenetic groups of heterotrophic bacterioplankton in monthly experiments over a complete annual cycle.
Starting in November 2012, surface water samples (2 L) from RADIALES station 2 will be collected and incubated in triplicates in the laboratory under three different temperature treatments (in situ, -3ºC and +3ºC). We will incubate two sets of bottles in parallel, one containing the whole community smaller than 200 µm (C) and the other one with water previously filtered through 1 µm (F) to minimize predation. Abundance, cell-size and biomass of heterotrophic bacteria will be monitored twice daily during the first days of the incubation (Fig. 17). In addition to total numbers, the physiological and phlylogenetic structure of the community will be assessed by single-cell probes and moleculat analyses, respectively. The effect of bottom-up controls will be considered at each experimental treatment by measuring, at the beginning and the end of the incubation plus one intermediate time, inorganic nutrient contentrations, bulk DOC and DON, coloured DOM and its fluorescent fraction. In addition, chlorophyll will be measured daily in C treatments. Similarly, the effect of top-down controls will be approached by measuring the abundance of heterotrophic flaglellates and viral particles.
Activity 3. Seasonal experiments comprehensively evaluating the temperature-dependence of the flow of organic matter through microbial plankton at the most significant oceanographic periods of the Southern Bay of Biscay continental shelf: spring phytoplankton bloom, summer stratification, autumn bloom and winter mixing.
During these periods, larger volumes of water will be incubated in the laboratory at the same temperature treatments with the aim of assessing in detail the carbon flow mediated by heterotrophic bacterioplankton. In addition to the variables listed for Activity 2, temperature response, particulate and dissolved primary production, bacterial production with the leucine and thymidine methods, bacterial respiration and growth efficiency and expression of functional genes will be detemined.
Alonso-Sáez L, Balagué V, Sa E, Sánchez O, González J M, Pinhassi J, Massana R, Pernthaler J, Pedrós-Alió C, Gasol, J M (2007b). FEMS Microbiol. Ecol. 60: 98-112.
Alonso-Saez L, Vázquez-Domínguez E, Cardelús C, Pinhassi J, Sala MM, Lekunberri I, Balagué V, Vila-Costa M, Unrein F, Massana R, Simó R, Gasol J M (2008b). Ecosystems 11: 397-409.
Atkinson D, Ciotti B J, Montagnes D J S (2003) Proc. R. Soc. B 270 2605-2611.
Azam F, Malfatti F (2007) Nat. Rev. Microbiol. 5: 782-791.
Behrenfeld M J, O’Malley R T, Siegel D A et al. (2006) Nature 444: 752–755.
Belgrano A, Allen A P, Enquist B J, Gillooly J F (2002) Ecol. Lett. 5: 611–613.
Bopp L, Monfray P, Aumont O, et al. (2001) Glob. Biogeochem. Cycles 15: 81-99.
Boyd P W, Doney S C (2002) Geophys. Res. Lett. 29: 1806.
Brown JH, Gillooly JF, Allen AP, et al. 2004. Ecology 85: 1771-1789.
Calvo-Díaz A, Morán X A G (2006) Aquat. Microb. Ecol. 42: 159-174.
Daufresne M, Lengfellner K, Sommer U (2009) Proc. Nat. Acad. Sci. USA 106: 12788-12793.
Duarte C M (2007) Trends Ecol. Evol. 22: 331-333.
Ducklow H W, Morán X A G, Murray A E (2010) In: Mitchell R, Gu J-D (eds), Environmental microbiology, 2nd edition, Wiley & Sons, New Jersey, pp. 1-31.
Ducklow H W, Purdie D A, Williams P J le B, Davies J M. 1986. Science 232: 865-867.
Edwards M, Richardson A J (2004) Nature 430: 881–884.
Falkowski P G, Oliver M J (2007) Nat. Rev. Microbiol. 5: 813-819.
Frederiksen M, Edwards M, Richardson A , Halliday N C, Wanless S (2006) J. Anim. Ecol. 75:1259–1268.
Grégori G, Citterio S, Ghiani A, Labra M, Sgorbati S, Brown S, Denis M (2001) Appl. Environ. Microbiol. 67: 4662–4670.
Henson S A, Sarmiento J L, Dunne J P et al. (2009) Biogeosci. Discuss. 6: 10311-10354.
Karner M B, DeLong E F, Karl D M (2001) Nature 409: 507-510.
Kirchman D L, Morán X A G, Ducklow H (2009) Nature Rev. Microbiol. 7: 451-459.
Li W K W (1998) Limnol. Oceanogr. 43: 1746-1753.
Li W K W, Harrison W G, Head E J H (2006) Proc. R. Soc. B 273: 1953-1960.
Li WKW, Harrison W G (2008) Limnol. Oceanogr. 53: 1734-1745.
Llope M, Anadón R, Sostres J A, Viesca L (2007) J. Geophys. Res. C 112: C07029.
López-Urrutia A, Morán X A G (2007) Ecology 88: 817-822.
López-Urrutia A, San Martin E, Harris R, Irigoien X (2006) Proc. Nat. Acad. Sci. USA 103: 8739-8744.
Morán X A G, Calvo-Díaz A, Ducklow H W (2010a) Aquat. Microb. Ecol. 58: 229-239.
Morán X A G, López-Urrutia Á, Calvo-Díaz A, Li W K W (2010b) Glob. Change Biol. 16: 1137-1144.
Pérez F F, Padín X A, Pazos Y, Gilcoto M, Cabanas M, Pardo P C, Doval M D, Farina-Busto L (2010) Glob. Change Biol. 16: 1258-1267.
Piontek J, Händel N, Langer G, Wohlers J, Riebesell U, Engel A (2009) Aquat. Microb. Ecol. 54: 305-318.
Richardson A J, Schoeman D S (2004) Science 305: 1609-1612.
Robinson C (2008) In: Kirchman D L (ed), Microbial ecology of the oceans, 2nd edition, Wiley & Sons, New Jersey, pp. 299-334.
Sarmiento J L, Slater R, Barber R et al. (2004) Glob. Biogeochem. Cycles 18: GB3003.
Savage V M, Gillooly J F, Brown J H, West G B, Charnov E L (2004) Am. Nat. 163: 429-441.
Steinberg D K, Carlson C A, Bates N R, et al. (2001) Deep-Sea Res II 48 1405-1447.
Straza et al 2009. Appl. Environ. Microbiol. 75: 4028-4034.
Teira E, Aranguren-Gassis M, González J, Martínez-García S, Perez P, Serret P (2009) Aquat. Microb. Ecol. 55: 81-93.
Vázquez-Domínguez E, Vaqué D, Gasol J M (2007) Glob. Change Biol. 13, 1327–1334.
Wohlers J, Engelb A, Zöllner E, Breithaupt P, Jürgen K, Hoppe H-G, Sommer U, Riebesell U (2009) Proc. Nat. Acad. Sci. USA 106: 7067–7072.
Research turns to acidification and warming in the Mediterranean Sea
Patrizia Ziveri, Universitat Autònoma de Barcelona (UAB), Institute of Environmental Science and Technology (ICTA), Edifici Cn, Campus UAB, 08193, Bellaterra, Barcelona, Spain
The Mediterranean Sea Acidification in a changing climate (MedSeA), a project funded by the European Commission under the 7th Framework Programme, assesses uncertainties, risks and thresholds related to Mediterranean acidification and warming at organism, ecosystem and economic scales. Eighteen institutions in 11 countries, mainly from the Mediterranean, are collaborating to identify where the impacts of acidification on Mediterranean waters will be most severe, taking into account the complete chain of causes and effects, from ocean chemistry through marine biology to socio-economic costs (Fig. 18). Policy measures for adaptation and mitigation that may vary geographically, and at the same time require coordination between regions or countries, will be proposed.
A basin-scale approach is adopted, with emphasis on conveying the acquired scientific knowledge to policy-makers, decision-makers, marine managers and other stakeholders through the formation of the Mediterranean Reference User Group (MRUG). Policy measures for adaptation and mitigation that may vary from one Mediterranean area to another, will be suggested. Thus, for the first time, project managers and other stakeholders will have up-to-date vulnerability maps upon which to design action plans.
Fine-scale regional study to resolve the complexity of the Mediterranean Sea acidification
As atmospheric CO2 levels rise, thermodynamics and air-sea gas transfer processes drive some of the excess CO2 into the ocean surface waters, alleviating climate change. This process leads to shifts in seawater acid-base chemical speciation, resulting in lowered pH, increased concentration of bicarbonate ions, reduced concentration of carbonate ions and calcium carbonate saturation state (in other words “ocean acidification”). This poses a threat to marine ecosystems and could potentially result in large changes in global biogeochemical cycles. This acidification could also have significant socio-economic impacts due to effects on tourism (e.g., as a result of coral degradation or invasion of non-endemic species) or fisheries and aquaculture (resulting from altered life cycles of key surface- and bottom-dwelling organisms, including shellfish). There is growing concern that impacts of anthropogenic acidification could propagate from individual organisms up through marine food webs, affecting commercial fisheries and shellfish industries, thereby threatening protein supply and food security for millions of people. The effects on such marine-based activities could indirectly affect land-based economic activities and jobs on a much larger scale.
Although the general impact of acidification on water chemistry is globally well understood, fine-scale regional models are needed to resolve the complexity of the physical and ecological interactions of small and complex basins like the Mediterranean Sea. The Mediterranean Sea is considered a small-scale ocean with high environmental variability and steep physicochemical gradients within a relatively limited area. Its circulation is characterized by zonal gradients of physicochemical variables, with salinity, temperature, stratification and alkalinity all increasing towards the east. The generally low-nutrient (from oligotrophic to ultraoligotrophic) waters offshore stand in contrast to many near-shore regions, often containing coral and seagrass ecosystems, which are affected by human-induced eutrophication. Thus, acidification is an additional anthropogenic pressure on Mediterranean Sea ecosystems, already suffering from overfishing, increasing sea surface temperatures, and invasions by alien species. To properly project how key biogeochemical and ecosystem processes will change, it is fundamental to adequately represent the general circulation of the Mediterranean basin, i.e., both the fine-scale processes that control it (e.g. eddies and deep convection), and the highly variable atmospheric forcing. With their relatively short residence times, Mediterranean Sea deep water changes are likely to lag behind surface waters by a few decades. Changes in deep-water formation sites, such as characterized by the dramatic shift with the Eastern Mediterranean Transient, are likely to coincide with changes in the hot spots where much of the anthropogenic CO2 is taken up from the atmosphere and transferred into the deep sea (where it is stored for longer periods). The efficiency of carbon uptake and export from the surface waters to the basin interior depends on the relatively rapid time scales for surface-to-deep water exchange and the Mediterranean general circulation. Thus, the combined effect of seawater acidification (absorbing anthropogenic CO2 per unit area) and low tropospheric warming on Mediterranean biogeochemistry, ecosystems and the ecosystem services they support (through direct impacts on its highly adapted calcareous and non-calcareous organisms) may be large.
The MedSeA project
A critical mass of scientists is joining forces in this interdisciplinary project to diagnose the current state of Mediterranean Sea acidification and to project how it will evolve in coming decades in terms of impacts on marine ecosystems and human society. New observational and experimental data on Mediterranean organism and ecosystem responses to acidification will be fed into existing fine-scale models of the Mediterranean Sea, modified to better represent key processes, to project future changes. MedSeA’s strategy is to focus on selected ecosystem and socio-economic variables that are likely to be affected by both acidification and warming, to study the combined effects through ship-based observations, laboratory and mesocosm experiments, physical-biogeochemical-ecosystem modelling and economic analyses. It aims to provide best estimates of future changes and related uncertainties in Mediterranean Sea pH, CaCO3 saturation states and other biogeochemical-ecosystem variables. In addition, changes in habitat suitability of relevant ecological and economically-important species will be assessed.
Dynamics of the Mediterranean carbonate chemistry from interannual to millennial timescales
As in the global ocean, when anthropogenic CO2 penetrates the Mediterranean waters, CO2-driven shifts in the carbonate chemical equilibria occur and seawater pH decreases. The MedSeA project is quantifying the rate of pH decrease and will ultimately produce maps identifying those sectors of the Mediterranean Sea currently most affected by pH changes.
As carbonate system data in the Mediterranean Sea are relatively scarce, new field measurements of carbonate system variables, both in the Western and Eastern basins, are being taken. These new data (from cruises and time-series stations) will complement existing data sets and provide a solid basis for understanding the temporal evolution of the penetration of anthropogenic carbon into the Mediterranean Sea. Data sets from survey cruises will provide the necessary links to the time-series stations and facilitate the construction of spatial gradients, thus providing insight on the penetration of anthropogenic carbon into the various Mediterranean water masses. Furthermore, the rate of increase of the pCO2 in surface seawater is under investigation to determine if it follows that of the atmosphere.
As results from cruises become available, it is expected that the parameterization of the variations of the total alkalinity (AT) and total dissolved inorganic carbon (CT), as a function of parameters such as salinity, temperature, and oxygen, will be improved. The few existing relationships present relatively large uncertainties, and it is anticipated that more accurate three-dimensional distributions of AT and CT fields throughout the Mediterranean Sea will be provided.
As the Mediterranean Sea is relatively unusual (e.g., warm waters throughout the water column, high salinity, non-Redfield ratios) compared with the open ocean, analysis of the (available and new) data sets will provide new insights for developing new way(s) of estimating anthropogenic carbon in the ocean. Initially, the three existing methods (TrOCA, MIX, improved Brewer/ Chen & Millero) will be considered. Results will be cross-compared and critically evaluated and improvements that take specific Mediterranean Sea features into account will be proposed. Current pH variations due to anthropogenic carbon penetration will be estimated from the anthropogenic carbon distributions, thus providing information on areas that could potentially be sensitive to future large pH decreases
Understanding the current and future dynamics and vulnerability of the Mediterranean marine carbonate system, however, requires knowledge of the long-term natural variability of the basin. This can be attained by providing proxy-based reconstructions of seawater pH, carbonate ion concentrations and pCO2, together with the response of marine calcifiers during key intervals of the Late Quaternary. These intervals are taken to represent discrete background states of the functioning of the basin or the climate system in general. Information derived from investigating the last millennium is critical to disclosing the natural range of variability of the Mediterranean carbonate system, before and during the anthropogenic perturbation of the global carbon cycle. The last deglaciation could be instructive as it represents an interval of natural CO2 build up (~80 ppm) in the atmosphere, although the change occurred over several millennia, as opposed to the much faster atmospheric CO2 rise observed in the past two centuries. Finally, the last interglacial period, notably in the eastern Mediterranean, is commonly referred to as a period of severely weakened deep and intermediate water overturning, high export of organic carbon to the deep sea (sapropel S5) and development of a large reservoir of respired CO2 in the subsurface. Accordingly, proxy-based reconstructions for this period could potentially inform the ongoing debate on the role of the basin’s thermohaline circulation and export production on the uptake of anthropogenic carbon.
Ecosystem responses, Mediterranean key-stone species and economic impact
MedSeA will define the susceptibility and resilience of key-stone species and endemic ecosystems to Mediterranean acidification and warming. Analysis of the experimental results will enable projections of changes to the services that these ecosystems and species provide. Some services, such as nursery grounds for fish, coastal protection, tourism, carbon sequestration and climate regulation, are likely to be very sensitive to climate change. To constrain projections, the MedSeA consortium will take an interdisciplinary approach, considering both physiological responses as well as ecological responses to environmental change.
The effects of acidification on selected Mediterranean pelagic and benthic species and on potentially sensitive processes such as photosynthesis and calcification will be assessed (Fig. 19). Geographical variability will be assessed by comparing responses in the Western and Eastern Mediterranean basins and Adriatic Sea. This will involve: 1) plankton monitoring at selected time-series stations and on regional cruises to characterize present conditions, 2) laboratory experiments on the response of single species and strains, 3) mesocosm experiments to determine the biogeochemical and community responses, and 4) natural analogue experiments in areas acidified by CO2 vents to determine the long-term effects of acidification across multiple generations of marine organisms (Fig. 20). The current functioning of pelagic and benthic marine communities will be related to carbonate chemistry and other environmental conditions (temperature, nutrients), over a wide geographic area, to inform predictive tools provided by the MedSeA modelling component.
To investigate the organisms, ecosystems and processes that are most likely to be susceptible to acidification in the Mediterranean, model species were selected regardless of whether or not they are unique or endemic to the Mediterranean Sea, major contributors to habitat building, major contributors to ecological function or species of economic value in the Mediterranean region.
Laboratory experiments investigate the individual and dual impacts of acidification and temperature on key pelagic and benthic organisms (coccolithophores, foraminifera, pteropods, jellyfish and endemic habitat-forming seagrasses, coralline algae, corals and vermetids). The potential effect of low phosphorous concentrations, which characterize the eastern Mediterranean and may alter the local outcomes of acidification, is also examined. The response of selected Mediterranean phytoplankton and zooplankton such as copepods is studied as they play a significant role in nutrient recycling in the water column and on the export of particulate matter out of the photic zone. During the last two to three decades, jellyfish blooms have increased throughout the Mediterranean Sea, often associated with warming caused by climate change. The effects of combined acidification and warming on ephyra viability and adult fitness in selected species will be also examined. Aquarium experiments will test adult fitness and reproductive output, larval viability, recruitment and survivorship of common Mediterranean species and of the invasive jellyfish species in the eastern Mediterranean.
Mesocosom incubations containing natural plankton assemblages will be performed in the Eastern and Western Mediterranean basins to examine the impact of changes in carbonate chemistry and temperature on biological and biogeochemical variables under natural and perturbed conditions. Mesocosm and natural analogue experiments will investigate and compare the impact of acidification on marine communities and processes. The first set of mesocosm experiments will be performed in June-July 2012. These will help to identify the impact of acidification on the planktonic community, including the diversity and succession of species, as well as the role of the microbial loop. It will be the first mesocosm study of the response of Mediterranean pelagic calcifiers to acidification.
Responses of benthic ecosystems: Studying benthic communities is essential for understanding the ecological effects of ocean acidification as 98% of all described marine species live on the sea floor. Key habitat-forming species of coralline algae, seagrass, corals and vermetids (Fig. 19) endemic to the Mediterranean, as well as the commercially important species that these habitats support, are targeted. MedSeA combines laboratory, mesocosm and volcanic CO2 vents to examine the long-term effects of elevated CO2 on the structure and functioning of benthic communities (Fig. 20).
Based on worldwide laboratory studies, calcareous coralline algae (CCA) appear to be among the first organisms to cease calcification due to lowered pH. First CO2 vent studies at Ischia show that similar effects may occur in Mediterranean waters. If so, this endangers a suite of diverse Mediterranean habitats (maerl beds, coralligenous habitats, trottoir, vermetid reefs) that are dependent on these calcifiers. MedSeA measures pH and thermal thresholds under which coralline algae are likely to slow calcification. The endemic Mediterranean seagrass Posidonia oceanica forms rich and diverse ecosystems. Work at CO2 vents indicates that this species may actually benefit from ocean acidification, but shows high sensitivity to elevated seawater temperature. Field assessments and experimental manipulations suggest that seagrass community metabolism and photosynthetic activity may buffer the effects of ocean acidification. Hence, declining seagrass meadows due to climate change may detrimentally affect habitat building, enhance beach erosion and locally moderate the effects of ocean acidification. Surveys of vermetid reefs and their associated CCA Neogoniolithon notarisi at field sites in Italy (Sicily) and Israel, combined with a series of mesocosm experiments, show that these engineering species are at risk and in some locations have already suffered local extinction.
A unique advantage of carrying out ocean acidification research in the Mediterranean is the availability of natural CO2 vent systems. These provide MedSeA researchers with the unique opportunity to examine the effects of reduced seawater pH on natural communities. Furthermore, by transplanting organisms along a pH gradient (function of distance from the vent) it is possible to examine short-term physiological responses to explain the observed long-term shifts in benthic communities.
Projected impacts of acidification on biogeochemistry and Mediterranean target species
It is well known that all future carbon emission scenarios from the IPCC indicate that ocean acidification will intensify. Global-scale models confirm this trend while providing a more realistic regional picture, relative to simple equilibrium calculations, particularly for key areas where there is substantial air-sea disequilibrium. The MedSeA project will expand projections of acidification to include the Mediterranean Sea by relying on modelling tools that aim to bridge experimental results with socio-economic studies.
Future projections of changes in Mediterranean Sea pH, CaCO3 saturation states, and other carbonate-system and biogeochemical-ecosystem variables are done using two ocean models, coupled with state-of-the-art biogeochemical models. They will be driven with forcing fields from coupled climate models to simulate 20th century climate conditions and future climate change scenarios. This strategy should help assess uncertainties of future projected changes in acidification by means of an ensemble of experiments. For the 20th century simulations, models will be forced with fields from regional climate models driven by observed changes in atmospheric greenhouse gases. Model skill and bias will be assessed by comparing simulated biogeochemical variables for the current state to available datasets. The simulated spread in future system responses will include differences between climate scenarios, models and assumptions about processes. The design of the simulations will allow researchers to (1) isolate impacts from increasing CO2 and climate change on the carbonate system variables and (2) examine the role played by pelagic biotic processes. By combining the results of this ensemble of experiments, MedSeA will go a long way towards estimating the uncertainty in future projections. Model projections will allow us to construct basin-scale sensitivity maps to ocean acidification, based on combined changes in key model state variables (e.g., pH, CaCO3 saturation states, O2, temperature, stratification). The integrated analysis of these maps, will help the MedSeA scientists to identify the regions of the Mediterranean Sea that are expected to be more vulnerable to acidification under future climate scenarios. To move this investigation from the level of biogeochemical response to the ecosystem level, one task is dedicated to constructing response functions of selected target species (shellfish, coralligenous organisms, etc.) to environmental parameters. This will produce hybrid habitat suitability patterns, i.e. a range of projected variations of the stress factors for growth and functioning of the target species. This information will be further exploited to assess socio-economic impacts associated with each considered target species, with a special focus on market species such as aquaculture mussels.
Socio-economic effects of Mediterranean Sea acidification and potential adaptation strategies and policy tools
MedSeA is developing a conceptual framework for studying the direct and indirect socio-economic (welfare) impacts of ocean acidification. This requires consideration of relevant dynamics and time scales, regional patterns, mechanisms (costs, prices, labour market, trade, income changes, expenditures, transport, etc.), valuation categories (use and non-use values and various sub-categories), economic demand categories and sectors (supply) and interactions between marine resource-based and other sectors (indirect effects). Much can be learned here from existing integrated economic-ecological studies of ecosystem change and values and meta-analysis of relevant past valuation studies.
Important sectors that could potentially be affected by ocean acidification are tourism, fisheries, aquaculture and jewelry production from red coral. Mediterranean acidification may affect the occurrence of harmful algal blooms, jellyfish distribution patterns, shellfish physiology and major contributors to habitat building. Links between these and other activities need to be established to identify indirect economic effects of ocean acidification. In addition, the capacity of the Mediterranean Sea to sequestrate carbon may be affected by ocean acidification. This can influence future concentrations of carbon dioxide in the atmosphere and thus global warming. The economic price of this can be determined, using available cost estimates of climate change damages.
Economic analyses will use scenarios developed in the MedSeA project, to which assumptions relating to relevant economic developments will be added (income growth, travel costs – climate regulation of air traffic and demand for tourism). In addition, synergetic effects of climate change (sea level rise, temperature change, altering weather conditions) and ocean acidification must also be considered. Direct effects of ocean acidification will be assessed, first with a review of existing studies on tourism and aquaculture for selected areas. This will focus on the Mediterranean, transferring and upscaling results to particular Mediterranean countries. Information obtained from valuation studies will be used to address use and non-use values. Meta-analyses and benefit/value transfer studies may be used in some cases, like the loss of nursery habitat value of seagrasses or corals. In other cases, the assessment will include partial equilibrium analysis (PEA), which addresses both market impacts (notably on tourism and aquaculture) and non-market impacts (ecosystem values, including cultural services and non-use values such as option, existence and bequest values). There is also evidence that the chronic acidification stress may cause major shifts in species composition and thus marine community structure, affecting organisms necessary or important in the diet of seafood species. Consequently, this could result in reduced Mediterranean marine biodiversity, which could potentially affect use and non-use values associated with both species diversity and unique Mediterranean ecosystems. The loss or degradation of coralligenous environments due to pH reduction could also have negative socio-economic impacts in regions that attract tourists for recreational diving, swimming, and viewing from underwater observatories or glass-bottom vessels.
Finally, adaptation strategies and policies will be formulated based on the qualitative and quantitative assessments of the natural and social science studies in the project. The objective is to cost-effectively reduce negative socio-economic impacts (damage costs) as much as possible. Strategies may involve technical, biological, legal, economic and spatial tools and instruments, as well as public versus private actions or some combination of these, such as risk management or insurance. Public actions involve the creation of adequate adaptation incentives for private economic agents through particular public policies. Different strategies may be considered for different areas of the Mediterranean region. To improve their effectiveness, some policies may require supranational cooperation or coordination. The expectation is that much can be learned from the growing literature on adaptation to climate change and associated analyses of policies and strategies.
Progress expected and initial results
The starting point is our current knowledge of the Mediterranean system. There is a lack of field-derived information on the carbonate system of the Mediterranean and related ecosystem components. A substantial effort is required to collate existing data and collect new information from the pelagic and benthic systems. The specific oceanographic features of the Mediterranean basin will be assessed using high-resolution, physical-biogeochemical models to provide basin-wide and surface-to-deep distributions of pH and carbonate-related variables. The models will also enable future projections following established scenarios for atmospheric CO2 emissions. MedSeA experimental and field observations, as well as model simulation output will be coordinated by comprehensive data management using a similar approach to the European Project on Ocean Acidification (EPOCA) and Biological Impact of Ocean Acidification (BIOACID) programme. The combination of the model projections, field and laboratory experiment results and socio-economic analyses will enable the development of vulnerability maps and possible economic impacts due to acidification in the Mediterranean. Emphasis will be put on producing the scientific output in a way that is understandable to policy makers and other key stakeholders. Close collaboration is anticipated with other ocean acidification initiatives (e.g. EPOCA, BIOACID, the UK Ocean Acidification Research Programme (UKOA)).
Initial project results confirm that the concentration of anthropogenic carbon extrapolated from Mediterranean field measurements is high and penetrating the deep sea. This process is changing the water chemistry, not only in the surface but also in the deep Mediterranean. The first results, based on a limited number of data, show that the Mediterranean Sea has undergone a reduction of the pH since the onset of industrialization and the effect is largest in the NW Mediterranean Sea. It is clear that due to the complexity and high variability of the basin, this process will have different regional impacts. This is anticipated to occur in regions where future model projections of sea surface temperature indicate a mean increase of winter and summer temperature of up to 2-4oC by the year 2050, if anthropogenic emissions remain unchanged.
MedSeA scientists are studying the responses of a wide range of organisms to ocean acidification - from free drifting plankton to bottom-dwelling organisms. Some, such as corals, seagrass and shellfish, are habitat builders (engeneering species), so their health is critical to hundreds of other organisms. Some have cultural and commercial value for the human population around the Mediterranean Sea. MedSeA scientists have identified and are currently focusing on ecosystems that are uniquely Mediterranean and are of special socio-economic value. Some of their recent findings highlight the sensitivity of some target benthic ecosystems (e.g. corals, shellfish, coralligenous habitat) to environmental change, suggesting that under the projected ocean acidification and global warming, fragile ecosystems of the Mediterranean Sea may experience loss of biodiversity.
This project is the first to offer a comprehensive view on the physical, biological and socio-economic impacts of ocean acidification in the Mediterranean area using a so-called scale-basin approach. On the basis of this, further evidence of the social costs of human emissions of carbon dioxide can be obtained. In addition, the results will allow us to identify particularly sensitive areas and to formulate effective and cost-effective adaptation policies and strategies at different scale levels.
Project coordinator: Patrizia Ziveri, Patrizia.Ziveri@uab.cat
Project manager: Rahiman Abdullah, Rahiman.Abdullah@uab.cat
For more information, please visit http://medsea-project.eu or the information outlet on Ocean Acidification, Climate and Environmental Change in the Mediterranean Sea at http://medseaclimatechange.wordpress.com/
ADEPT: Aerosol deposition and ocean plankton dynamics
Francesc Peters (principal investigator), Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003 Barcelona, Catalunya, Spain
Phone: +34 93 230 9598
ADEPT is a Spanish project (2012-2014) funded by the Ministerio de Economía y Competitividad that addresses the study of the effect of atmospheric aerosol deposition on the dynamics of a marine LNLC (low nutrient low chlorophyll) system, namely the Mediterranean. To achieve its goal, ADEPT uses a multiscale and complementary approach (Fig. 21). At the Mediterranean basin scale we relate satellite chlorophyll data with modeled Saharan dust deposition. At the coastal scale, we measure deposition at several locations across the NW Mediterranean and simultaneously sample chemical and biological parameters of the water column. We analyze relationships between both sets of variables and also with aerosols in air using time series analysis (Guadayol et al. 2009). For the needed water column sampling frequency we depend on the collaboration of non-scientists. In addition we conduct laboratory experiments with aerosol amendments to seawater to study plankton stimulation dynamics, utilization of organic matter by bacteria, and changes in bacterial composition and diversity, all for a better mechanistic understanding of the processes involved.
Atmospheric deposition is of unquestionable importance over long time scales, seemingly driving oceanic biogeochemical fluxes at the global scale (Mahowald et al. 2010). Dust of mineral origin is the main contributor to such worldwide deposition and the Saharan and Sahel regions are two of the most active ones in terms of dust export (Prospero et al. 1996). Pérez et al. (2007) estimate that these two areas are responsible for more than half of the world’s mineral dust emissions. A remarkable part of this dust travels across the LNLC Mediterranean Sea and is deposited within its basin, including the coastal areas (Loÿe-Pilot & Martin 1996, Guerzoni et al. 1999). Deposition of aerosols from anthropogenic origin is also important, fueled mainly by the more industrialized northern Mediterranean shore with a large potential impact near the coastal areas (Escudero et al. 2007, Querol et al. 2009a). Global changes in the region (Solomon et al. 2007) such as increased ocean temperature and stratification and increased land erosion and anthropogenic emissions all paint a scenario for an increased sensitivity of the Mediterranean ecosystem to atmospheric deposition. Basin-wide, the input of nutrients to the Mediterranean Sea from atmospheric deposition is roughly equal to the land-based input. The potential ecosystem effects of such inputs, however, must be necessarily different as land-based sources are concentrated in coastal areas, while atmospheric inputs are distributed over large areas of the basin.
The Mediterranean is notorious for its high N:P nutrient ratio and the terrestrial and atmospheric inputs also have N:P larger than the Redfield ratio of 16 (Bethoux et al. 1998, Krom et al. 2010). Terrestrial N:P ratios are increasing, especially in industrialized areas owing to human efforts in nutrient reduction. The ban of P in detergents and the more or less straightforward removal of P compared to N in wastewater treatment plants all help to exacerbate the trend for a high N:P input into the ocean. Thus, phosphorus seems to be the primary limiting element in the LNLC Mediterranean, especially over the longer time scales. However, most elements are in short supply and when there is a limitation relieve of one element, another element starts to limit the system, at least temporarily (Marty et al. 2002, Sala et al. 2002, Lucea et al. 2005, Bonnet & Guieu 2006, Pinhassi et al. 2006, Pulido-Villena et al. 2010). Even carbon can limit the system from the heterotrophic production standpoint. This generates a range of dynamic imbalances in nutrient availability. Iron which is largely supplied by atmospheric deposition to the open Mediterranean does not seem to limit microbial enzymatic activities (Krom et al. 2010, Wagener et al. 2010), although this may not be true at all times (Bonnet & Guieu 2006, Wagener et al. 2010). This situation increases the chances that any atmospheric input, even if small, alleviates nutrient limitation to some extent, at least during the spatio-temporal windows of opportunity where imbalances are more severe.
Mean annual atmospheric aerosol load (PM10) in the Mediterranean shows values ranging from 10 to 31 μg m-3 (Querol et al. 2009b). Saharan dust outbreaks that are prominent during summer in the W. Mediterranean and during spring – early summer in the E. Mediterranean can increase these loads to over 1000 μg m-3 in the Eastern and over 100 μg m-3 in the Western sub basins. Aerosol content shows increases towards the Eastern Mediterranean. Actual deposition data is much more scarce and variable with wet deposition (rain) showing the highest flux rates per units area. Ridame & Guieu (2002) measured 8 g of dust L-1 in one event. Avila et al. (1997) measured up to 19 g m-2 at Montseny (Spain), and the event of February 22, 2004 in the NW Mediterranean left depositions of more than 50 g m-2 at some locations. Markaki et al. (2010) measured dissolved inorganic phosphorous (DIP) fluxes of 243 to 608 μmol m-2 y-1, and dissolved inorganic nitrogen (DIN) fluxes of 18.1 to 77.9 mmol m-2 y-1. While DIN deposition largely coincided with winter rainfall, DIP deposition was more variable throughout the year. Depending on the temporal episodic nature of this atmospheric DIP and DIN, and the depth of the upper mixed layer, there is the potential to significantly increase nutrient levels in water and increase primary production (Ridame & Guieu 2002, Izquierdo et al. 2011) by 15%. In the Mediterranean, even in coastal areas it is easy to find very low nutrient concentrations. In Blanes Bay (Spain) for example, during a regular monthly survey from 2001 to 2007, 31% of samples were below 0.1 μmol L-1 of PO4-3 and 1.6 μmol L-1 DIN. The organic carbon associated to aerosols, mostly of anthropogenic origin, that may fuel bacterial respiration and growth deserves special mention. Aerosols from anthropogenically influenced areas have a higher proportion of organic carbon with respect to elemental carbon (OC/EC) that derive mainly from high temperature processes (Rodríguez et al. 2004). Again, during an event and depending on the lability of the deposited organic matter compared to that present in the water, atmospheric inputs may increase DOC concentrations and spur bacterial activity.
Experiments with aerosol amendments have shown stimulations of plankton growth or activity. Bacterial respiration and growth, is the first response often observed in aerosol amendment experiments (Lekunberri et al. 2010, Pulido-Villena et al. 2008, Marañón et al. 2010, Romero et al. 2011) especially under oligotrophic situations (Marañón et al. 2010), albeit not always (Herut et al. 2005, Duarte et al. 2006). Bacterial production and the subsequent grazing by heterotrophic protists will invariably recycle inorganic nutrients based on stoichiometry and these nutrients may then secondarily stimulate primary production. This indirect effect on primary producers might be weaker than a direct stimulation and imply a delay in time, which may range over several weeks in the ocean, all of which complicates the detection of aerosol input on plankton dynamics at the basin level.
Satellite derived chlorophyll has been correlated to atmospheric aerosol load in several ocean areas including the Mediterranean (Gabric et al. 2002, Dulac et al. 2004, Volpe et al. 2009, Justiniano et al. 2010), although satellite signal interference and spurious relations question the relationships (Volpe et al. 2009). Clear effects at ecosystem timescales have been relatively elusive, probably because a) small signals have to be discerned from larger background drivers and b) atmospheric optical depth data might not be the best proxy for actual deposition.
ADEPT (www.icm.csic.es/bio/adept) had its kick-off meeting in Barcelona on Feb. 2, 2012, and included scientists from a wide range of disciplines and also non-scientific collaborators. We have placed bulk deposition measurement stations at the Institute of Marine Sciences in Barcelona (Fig. 22) and at the Center of Advanced Studies of Blanes both in Spain. There are plans to place a third at the Stazione Zoologica Anton Dohrn in Naples, Italy. We analyze mainly inorganic nutrients (Fig. 23) and organic carbon. We have also placed a pollen collector at the Blanes site to determine pollen dynamics (Belmonte & Roura 1991) and the potential contribution to organic matter deposition. We will soon start daily water column sampling at several locations along the Spanish coast with the help of a range of collaborators. The project benefits from the added logistics and manpower. Stakeholders appreciate the proximity of scientific efforts to their environmental concerns and the bonds that develop between scientists and society at large should benefit everyone. We have also started to relate modeled deposition data (BSC-DREAM: Barcelona Supercomputing Center - Dust REgional Atmospheric Model) with satellite derived chlorophyll. Laboratory plankton stimulation experiments, organic matter degradation experiments and bacterial composition shift studies will start sometime later in 2012. We will be happy to collaborate/network with parties interested in studying the potential effects of atmospheric deposition on biogeochemical cycles and ecosystem dynamics in the Mediterranean or other LNLC areas.
Avila, A., Queralt-Mitjans, I., Alarcón M. 1997. Mineralogical composition of African dust delivered by red rains over northeastern Spain. J. Geophys. Res. 102: 21977-21996. doi:10.1029/97JD00485
Belmonte, J., Roure, J.M. 1991. Characteristics of the aeropollen dynamics at several localities in Spain. Grana. 30: 364-372.
Béthoux, J.P., Morin, P., Chaumery, C., Connan, O., Gentili, B. & Ruiz-Pino, D., 1998. Nutrients in the Mediterranean Sea, mass balance and statistical analysis of concentrations with respect to environmental change. Marine Chemistry. 63: 155-169.
Bonnet, S., Guieu, C. 2006. Atmospheric forcing on the annual iron cycle in the western Mediterranean Sea: A 1-year survey. J. Geophys. Res. 111: C09010. doi:10.1029/2005JC003213.
Duarte, C.M., Dachs, J., Llabres, M., Alonso-Laita, P., Gasol, J.M., Tovar-Sanchez, A., Sanudo-Wilhemy, S., Agusti, S., 2006. Aerosol inputs enhance new production in the subtropical northeast Atlantic. Journal of Geophysical Research-Biogeosciences 111. doi: 1G04006 - 0.1029/2005JG000140.
Dulac, F., Moulin, C., Planquette, H., Schulz, M., Tartar, M. 2004. African dust deposition and ocean colour in the Eastern Mediterranean. In Rapp. Comm. Int. Mer Médit., Vol. 37, p. 190. Commission Internationale pour l’Exploration Scientifique de la Méditerranée, Monaco.
Escudero, M., Querol, X., Pey, J., Alastuey, A., Pérez, N., Ferreira, F., Alonso, S., Rodríguez, S., Cuevas, E. 2007. A methodology for the quantification of the net African dust load in air quality monitoring networks. Atmospheric Environment. 41: 5516–5524
Gabric, A.J., Cropp, R., Ayers, G.P., Tainsh, G.M., Braddock, R. 2002. Coupling between cycles of phytoplankton biomass and aerosol optical depth as derived from SeaWiFS time series in the Subantarctic Southern Ocean. Geophys. Res. Letters. 29: 1112. doi:10.1029/2001GL013545
Guadayol, Ò., Peters, F., Marrasé, C., Gasol, J.M., Roldán, C., Berdalet, E., Massana, R., Sabata, A. 2009. Episodic meteorological and nutrient-load events as drivers of coastal planktonic ecosystem dynamics: a time series analysis. Marine Ecology Progress Series. 381: 139-155. doi: 10.3354/meps07939.
Guerzoni, S., Chester, R., Dulac, F., Herut, B., Loÿe-Pilot, M.D., Measures, C., Migon, C., Molinaroli, E., Moulin, C., Rossini, P., Saydam, C., Soudine, A., Ziveri, P. 1999. The role of atmospheric deposition in the biogeochemistry of the Mediterranean Sea. Progress in Oceanography. 44: 147-190.
Herut, B., Zohary, T., Krom, M.D., Mantoura, R.F.C., Pitta, P., Psarra, S., Rassoulzadegan, F., Tanaka, T., Thingstad, T.F. 2005. Response of East Mediterranean surface water to Saharan dust: On-board microcosm experiment and field observations. Deep-Sea Research II. 52: 3024–3040.
Izquierdo, R., Benítez-Nelson, C.R., Masqué, P., Castillo, S., Alastuey, A., Àvila, A. 2012. Atmospheric phosphorus deposition in a near-coastal rural site in the NE Iberian Peninsula and its role in marine productivity. Atmospheric Environment. 49: 361-370.
Justiniano, R. Armstrong, Y. Detres. 2010. Time series analysis of aerosol optical thickness and chlorophyll concentration in the North Atlantic Ocean and Caribbean Sea using satellite data. Ocean Sciences Meeting 2010.
Krom, M.D., Emeis, K.-C., Van Cappellen, P. 2010. Why is the Eastern Mediterranean phosphorus limited? Progress in Oceanography. 85: 236–244. doi: 10.1016/j.pocean.2010.03.003
Lekunberri, I., Lefort, T., Romero, E., Vázquez-Domínguez, E., Romera-Castillo, C., Marrasé, C., Peters, F., Weinbauer, M., Gasol, J.M. 2010. Effects of a dust deposition event on coastal marine microbial abundance and activity, bacterial community structure and ecosystem function. Journal of Plankton Research. 32: 381-396. doi: 10.1093/plankt/fbp137.
Loÿe-Pilot, M.D., Martin, J.M., 1996. Saharan dust input to the western Mediterranean: An eleven years record in Corsica. In: Guerzoni, S., Chester, R. (Eds.), The Impact of Desert Dust across the Mediterranean.
Lucea, A., Duarte, C.M., Agustí, S., Kennedy, H. 2005. Nutrient dynamics and ecosystem metabolism in the Bay of Blanes (NW Mediterranean). Biogeochemistry. 73: 303-323.
Mahowald, N. M. et al. 2010. Observed 20th century desert dust variability: impact on climate and biogeochemistry. Atmos. Chem. Phys. 10: 10875–10893. doi:10.5194/acp-10-10875-2010
Marañón, E., Fernández, A., Mouriño-Carballido, B., Martínez-García, S., Teira, E., Cermeño, P., Chouciño, P., Huete-Ortega, M., Fernández, E., Calvo-Díaz, A., Morán, X.A.G., Bode, A., Moreno-Ostos, E., Varela, M.M., Patey, M.D., Achterberg, E.P. 2010. Degree of oligotrophy controls the response of microbial plankton to Saharan dust. Limnol. Oceanogr. 55: 2339–2352, doi:10.4319/lo.2010.55.6.2339
Markaki, Z., Loÿe- Pilot, M.D., Violaki, K., Benyahya, L., Mihalopoulos, N., 2010. Variability of atmospheric deposition of dissolved nitrogen and phosphorus in the Mediterranean and possible link to the anomalous seawater N/P ratio. Marine Chemistry. 120: 187–194
Marty, J.C., Chiaverini, J., Pizay, M.D., Avril, B. 2002. Seasonal and interannual dynamics of nutrients and phytoplankton pigments in the western Mediterranean Sea at the DYFAMED time-series station (1991-1999). Deep-Sea Research Part II-Topical Studies in Oceanography. 49. 1965-1985.
Pérez, C., Jiménez, P., Jorba, O., Baldasano, J. M., Cuevas, E., Nickovic, S., Querol, X. 2007. Long-term trends (1987–2006) of Saharan dust over the Mediterranean and the Canary Islands with the DREAM regional dust model. Geophys. Res. Abstracts. 9: 08525.
Pinhassi, J., Gómez-Consarnau, L., Alonso-Sáez, L., Sala, M.M., Vidal, M., Pedrós-Alió, C., Gasol, J.M., 2006. Seasonal changes in bacterioplankton nutrient limitation and their effects on bacterial community composition in the NW Mediterranean Sea. Aquatic Microbial Ecology. 44: 241-252.
Prospero, J.M., Barrett, K., Church, T., Dentener, F., Duce, R.A., Galloway, J.N., Levy, H., Moody, J., Quinn, P., 1996. Atmospheric deposition of nutrients to the North Atlantic Basin. Biogeochemistry. 35: 27-73.
Pulido-Villena, E, Wagener, T. Guieu, C. 2008. Bacterial response to dust pulses in the western Mediterranean: Implications for carbon cycling in the oligotrophic ocean. Global Biogeochem. Cycles 22: GB1020, doi:10.1029/2007GB003091
Pulido-Villena, E., Rérolle, V., Guieu, C. 2010. Transient fertilizing effect of dust in P-deficient LNLC surface ocean. Geophysical Research Letters. 37: L01603. doi:10.1029/2009GL041415.
Querol, X., Alastuey, A., Pey, J., Cusack, M., Pérez, N., Mihalopoulos, N., Theodosi, C., Gerasopoulos, E., Kubilay, N., Koçak, M. 2009. Variability in regional background aerosols within the Mediterranean. Atmospheric Chemistry and Physics. 9: 4575-4591.
Querol, X., Pey, J., Pandolfi, M., Alastuey, A., Cusack, M., Pérez, N., Moreno, T., Viana, M., Mihalopoulos, N., Kallos, G., Kleanthous, S. 2009. African dust contributions to mean ambient PM10 mass-levels across the Mediterranean Basin. Atmospheric Environment. 43: 4266-4277.
Ridame, C., Guieu, C., 2002. Saharan input of phosphate to the oligotrophic water of the open western Mediterranean Sea. Limnology and Oceanography. 47: 856-869.
Rodríguez, S. Querol, X., Alastuey, A., Viana, M., Alarcón, M., Mantilla, E., Ruiz, C.R. 2004. Comparative PM10–PM2.5 source contribution study at rural, urban and industrial sites during PM episodes in Eastern Spain. Science of the Total Environment. 328: 95-113. doi:10.1016/S0048-9697(03)00411-X
Romero, E., Peters, F., Marrasé, C., Guadayol, O., Gasol, J.M., Weinbauer, M.G. 2011. Coastal Mediterranean plankton stimulation dynamics through a dust storm event: An experimental simulation. Estuarine, Coastal and Shelf Science. 93: 27-39. doi: 10.1016/j.ecss.2011.03.019.
Sala, M.M., Peters, F., Gasol, J.M., Pedrós-Alió, C., Marrasé, C., Vaqué, D., 2002. Seasonal and spatial variations in the nutrient limitation of bacterioplankton growth in the northwestern Mediterranean. Aquatic Microbial Ecology 27, 47-56.
Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K.B., Tignor, M., Miller, H.L. (eds.). 2007. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp.
Volpe, G., Banzon, V. F., Evans, R. H., Santoleri, R., Mariano, A. J., and Sciarra, R. 2009. Satellite observations of the impact of dust in a low-nutrient, low-chlorophyll region: Fertilization or artifact? Global Biogeochem. Cy. 23, GB3007, doi:10.1029/2008GB003216.
Wagener, T., Guieu, C., and Leblond, N. 2010. Effects of dust deposition on iron cycle in the surface Mediterranean Sea: results from a mesocosm seeding experiment. Biogeosciences. 7: 3769–3781, doi: www.biogeosciences.net/7/3769/2010.
IMBER future events
ClimECO3: IMBER Summer School (23-28 July 2012, Ankara, Turkey)
IMBIZO III (28-31 January 2013, Goa, India)
The future of marine biogeochemistry, ecosystems and societies.
Multi-dimensional approaches to the challenges of global change in continental margins and open ocean systems.
Register and submit an abstract before 15 July 2012
For more info, please visit IMBIZO lll website…
IMBER endorsed events
2nd ICES/PICES/IOC International Symposium (15-19 May 2012, Yeosu, Korea)
Second international symposium on "Effects of Climate Change on the World's Oceans"IMBER workshop sponsored by ESSAS and ICED on "Effects of climate change on advective fluxes in high latitude regions" (14 May 2012)
Needs assessment for capacity development for IMBER in the Asia-Pacific region (31 July - 4 August 2012, ECNU, Shanghai, China)
Members of the IMBER Capacity Building Task Team and other capacity building experts from around the world will use a case study approach to assess capacity building efforts for IMBER-related research undertaken in the Asia-Pacific region. This workshop will analyse and evaluate these efforts and identify where capacity development still need to be addressed.
The results of the workshop will provide IMBER, relevant international agencies and decision makers with a scientific basis for developing a capacity building strategy to enhance integrated marine biogeochemistry and ecosystem research in the Asia-Pacific region.
The list of IMBER relevant meetings in 2012 are available here
- Barton A., Hales B., Waldbusser G. G., Langdon C. & Feely, R. A., 2012. The Pacific oyster, Crassostrea gigas, shows negative correlation to naturally elevated carbon dioxide levels: implications for near-term ocean acidification effects. Limnology and Oceanography 57(3): 698-710.
- Chang C. Y., P. C. Ho, A. Sastri, Y. C. Lee, G. C. Gong, and C. H. Hsieh, 2012. Methods of training set construction toward improving classification performance for automated mesozooplankton image classification system. Continental Shelf Research. 36: 19-28.
- Chung, C.-C., G.-C. Gong and C.-C. Hung, 2012. Effect of Typhoon Morakot on microphytoplankton population dynamics in the subtropical Northwest Pacific, Marine Ecology Progress Series,448, 39-49.
- Chuang, PS, MI Chen, JC Shiao, 2012. Identification of Tuna species by a Real-Time Polymerase Chain Reaction Technique. Food Chemistry. DOI: 10.1016/j.foodchem.2012.01.076.
- Coyle K.O., L.B Eisner, F.J. Mueter, A.I. Pinchuk, M.A. Janout, E.V. Farley, K. Cieciel, and A.G. Andrews, 2011. Climate change in the southeastern Bering Sea: impacts on pollock stocks and implications for the oscillating control hypothesis. Fish. Oceanogr. 20(2): 139–156.
- Danielson S., L. Eisner, T. Weingartner, and K. Aagaard, 2011. Thermal and haline variability over the central Bering Sea shelf: Seasonal and interannual perspectives. Continental Shelf Research 31: 539–554.
- Drinkwater, K.F., 2011. The influence of climate variability and change on the ecosystems of the Barents Sea and adjacent waters: Review and synthesis of recent studies from the NESSAS Project. Progress in Oceanography 90: 47-61.
- Drinkwater, K., H. Loeng, O. Titov and V. Boitsov, 2011. Climate impacts on the Barents Sea ecosystem. pp. 777-807. In The Barents Sea. Ecosystem, resources, and management. Half a century of Russian-Norwegian cooperation, Ed. by T. Jakobsen. and V.K. Ozhigin, V.K. Tapir Academic Press, Trondheim.
- Erga, S.R., N. Ssebiyonga, B. Hamre, . Frette, E. Hovland, K. Drinkwater, and F. Rey, 2012. Environmental control of phytoplankton distribution and photosynthetic capacity at the Jan Mayen Front in the Norwegian Sea. Journal of Marine Systems doi: 10.1016/j.jmarsys.2012.01.006.
- Fer, I. and K. Drinkwater, 2012. Mixing in the Barents Sea Polar Front near Hopen in spring. Journal of Marine Systems. doi: 10.1016/j.jmarsys.2012.01.005.
- Fienup-Riordan A. and E. Carmack, (In Press) . The Ocean is Always Changing: Nearshore and Farshore Perspectives on Arctic Coastal Seas. Journal of Oceanography .
- Fienup-Riordan A. and A. Rearden, 2011 (In Press). Ellavut/Our Yup'ik World and Weather. University of Washington Press.
- Frieder C. A., Nam S. H., Martz T. R., & Levin L. A., 2012. High temporal and spatial variability of dissolved oxygen and pH in a nearshore California kelp forest. Biogeosciences Discussions 9(3): 4099-4132. Article
- Friedland, K.D., C. Stock, K.F. Drinkwater, J. Link, R. Leaf, B. Shank, J. Rose, C.H. Pilskaln, and M. Fogarty, 2012. Pathways between primary production and fisheries yields of Large Marine Ecosystems. PlosOne 7: e28945. doi:1371/journal.pone.0028945.
- Gattuso, J.-P., Thomas, E., 2012. Ocean Acidification: How will ongoing ocean acidification affect marine life? PAGES newsletter, 20(1), 36-37.
- Gibson, G.A. and Y.H. Spitz, 2011. Impacts of biological parameterisation, initial conditions, and environmental forcing on parameter sensitivity and uncertainty in a marine ecosystem model for the Bering Sea. Journal of Marine Systems (In Press).
- Gislason, Astthor and Teresa Silva, 2011. Distribution and abundance of Chaetognaths at Siglunes trancect north of Iceland during spring 2008, 2009 and 2010 (In Icelandic, English summary). Hafrannsóknir 158: 56-61.
- Gruber, N., 2011. Warming up, turning sour, losing breath: Ocean biogeochemistry under global change. Phil. Trans. R. Soc. A 369 1980-1996. doi: 10.1098/rsta.2011.0003.
- Havice, E., Campling, L., 2011. Shifting Tides in the Western and Central Pacific Ocean Tuna Fishery: The Political Economy of Regulation and Industry Responses. Global Environmental Politics 10 (1): 89-114.
- Hildur Petursdottir, 2011. Trophic interactions among zooplankton and fish species within the pelagic ecosystem of the Iceland Sea. ICES CM 2011/K:05.
- Hood, R., Yu, W., Masumoto, Y., Wiggert, J., Naqvi, W., McCreary, J., Yu, Z., and Beckley, L., 2012. SIBER and IOP: Joint activities and science results. CLIVAR Exchanges No. 57, Vol. 16 (3): 17-20.
- Hoogstraten, A., Timmermans, K.R., de Baar, H.J.W., 2012. Morphological and physiological effects in proboscia alata (bacillariophyceae) grown under different light and co2 conditions of the modern southern ocean. Journal of Phycology. dio: 10.1111/j.1529-8817.2012.01148.x
- Hunt Jr., G.L., K.O. Coyle, L. Eisner, E.V. Farley, R. Heintz, F.J. Mueter, J.M. Napp, J.E. Overland, P.H. Ressler, S. Salo, and P.J. Stabeno, 2011. Climate impacts on eastern Bering Sea food webs: A synthesis of new data and an assessment of the Oscillating Control Hypothesis. ICES J. Mar. Sci. 68: 1230-1243.
- Kristiansen, T., K. Drinkwater, G. Lough, and S. Sundby, 2011. Recruitment variability in North Atlantic cod (Gadus morhua) and match/mismatch dynamics. PLoS ONE 6(3): e17456. doi:10.1371/journal.pone.0017456.
- Lan, Kuo-Wei, Hiroshi Kawamura, Ming-An Lee, Hsueh-Jung Lu, Teruhisa Shimada, Kohtaro Hosoda and Futoki Sakaida, 2012. Relationship between albacore (Thunnus alalunga) fishing grounds in the Indian Ocean and the thermal environment revealed by cloud-free microwave sea surface temperature. Fisheries Research, 113:1-7. doi:10.1016/j.fishres.2011.08.017
- Lidbury I., Johnson V., Hall-Spencer J. M., Munn C. B., & Cunliffe M., in press. Community-level response of coastal microbial biofilms to ocean acidification in a natural carbon dioxide vent ecosystem. Marine Pollution Bulletin doi:10.1016/j.marpolbul.2012.02.011. Article (subscription required).
- Lin, HY, JC Shiao, YG Chen, Y Iizuka, 2012. Ontogenetic vertical migration of grenadiers revealed by otolith microstructures and stable isotopic composition. Deep-Sea Research Part I. 61: 123-130. DOI: 10.1016/j.dsr.2011.12.005.
- Lin, Y.-C., T. Campbell, C.-C. Chung, G.-C. Gong, K.-P. Chiang, and A. Worden, 2012. Distribution patterns and phylogeny of marine Stramenopiles (MAST) in the North Pacific Ocean, Applied and Environmental Microbiology,doi:10.1128/AEM.06952-11,3387-3399.
- Lohbeck K. T., Riebesell U. & Reusch T. B. H., in press. Adaptive evolution of a key phytoplankton species to ocean acidification. Nature Geoscience. doi: 10.1038/ngeo1441.
- Mueter, F.J., N.A. Bond, J.N. Ianelli, and A.B. Hollowed, 2011. Expected declines in recruitment of walleye pollock (Theragra chalcogramma) in the eastern Bering Sea under future climate change. ICES J. Mar. Sci. 68: 1284-1296.
- Mueter, F. J., E. C. Siddon, and G. L. Hunt Jr., 2011. Climate change brings uncertain future for subarctic marine ecosystems and fisheries. Pages 329-357 In A. L. Lovecraft and H. Eicken, editors. North by 2020: Perspectives on Alaska's Changing Social-Ecological Systems. University of Alaska Press, Fairbanks.
- Oguz, T., Akoglu, E., Salihoglu, B., 2011. Current state of overfishing and its regional differences in the Black Sea. Ocean & Coastal Management. 58: 47-56.
- Pedrotti , M. L., Fiorini, S., Kerros, M.-E., Middelburg, J.J., Gattuso, J.-P., 2012. Variable production of transparent exopolymeric particles by haploid and diploid life stages of coccolithophores grown under different CO2 concentrations. Journal of Plankton Research. dio: 10.1093/plankt/fbs012
- Pepin, P., C.C. Parrish, and E.J.H. Head, 2011. Condition of Calanus finmarchicus on the Newfoundland Shelf and in the western Labrador Sea in late autumn: Fatty acid biomarker evidence of size-dependent differential feeding histories. Mar. Ecol. Prog. Ser. 423, 155-166.
- Philippart, C.J.M. R. Anadón, R. Danovaro, J.W. Dippner, K.F. Drinkwater, S.J. Hawkins, T. Oguz, G. O’Sullivan and P.C. Reid, 2011. Impacts of climate change on European marine ecosystems: Observations, expectations and indicators. Journal of Experimental Marine Biology and Ecology 400: 52-69.
- Siddon, E.C., J.T. Duffy-Anderson, and F.J. Mueter, 2011. Community-level response of fish larvae to environmental variability in the southeastern Bering Sea. Mar. Ecol. Prog. Ser. Vol. 426: 225–239, 2011. doi: 10.3354/meps09009
- Sigler, M.I., Renner, M., Danielson, S.L., Eisner, L.B., Lauth, R.R., Kuletz, K.J., Logerwell, E.A., Hunt, G.L., Jr., 2011. Fluxes, fins, and feathers: Relationships among the Bering, Chukchi, and Beaufort Seas in a time of climate change. Oceanography 24: 250-265.
- Skogen, M. D., K. Drinkwater, S.S. Hjøllo, and C. Schrum, 2011. North Sea sensitivity to atmospheric forcing, Journal of Marine Systems 85: 106-114.
- Tsai, A.-Y., G.-C. Gong, R. W. Sanders, K.-P. Chiang, C.-F. Chao, 2012. Heterotrophic bacterial and Synechococcus spp. Growth and mortality along the inshore-offshore in the East China Sea in summer, Journal of Oceanography, 68, 151-162.
- Tu, C. Y., Y. H. Tzeng, T. S. Chiu, and C. H. Hsieh, 2012. Using coupled fish behavior-hydrodynamic model to investigate spawning migration of Japanese anchovy, Engraulis japonicus, from the East China Sea to Taiwan. Fisheries Oceanography. doi:10.1111/j.1365-2419.2012.00619.x.
- Tzeng, W. N., Y. H. Tzeng, Y. S. Han, C. C. Hsu, C. W. Chang, S. Jan, E. Di Lorenzo, and C. H. Hsieh, 2012. Evaluation of multi-scale climate effects on the recruitment of Japanese eel, Anguilla japonica, to Taiwan. PLoS One 7:e30805.
- Vázquez-Rodríguez M., Pérez F. F., Velo A., Ríos A. F., & Mercier H., 2012. Observed trends of anthropogenic acidification in North Atlantic water masses. Biogeosciences Discussions 9(3): 3003-3030. Article
List of acronyms
- IPO: International Project Office
- SCOR: Scientific Committee on Oceanic Research
Should you wish to contribute an article for the IMBER Update, please contact Lisa Maddison
Published by IMBER
Editors: IMBER IPO