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Drivers of recent Chesapeake Bay warming

Posted by mmaheigan

· Friday, August 26th, 2022

Coastal water temperatures have been increasing globally with more frequent marine heat waves threatening marine life and nearshore communities reliant upon these ecosystems. Often, this warming is assumed to be uniform in space and time; however, this is not the case in the Chesapeake Bay, where warming waters play a major role in exacerbating low oxygen levels and indirectly limiting the efficacy of nutrient reduction efforts on land.

New research published in the Journal of the American Water Resources Association combined long-term observations and a hydrodynamic model to quantify the temporal and spatial variability in warming Chesapeake Bay waters, and identify the contributions of different mechanisms driving these historical temperature changes. While winter temperatures have warmed by less than a half a degree over the past 30 years, summer temperatures have warmed by nearly 1.5 °C, with similar increases at the surface and bottom. In cooler months, the atmosphere was the dominant driver of warming throughout the majority of the Bay, but oceanic warming explained more than half of the increased summer temperatures in the southern Bay nearest the Atlantic.

Figure 1: Relative contribution of different factors to warm-month Chesapeake Bay temperature change over the period 1985-2015. Percentages correspond to average main channel contributions for each component.

Warming temperatures have potentially significant implications for the future size of the Chesapeake Bay dead zone, and the marine species directly affected by these low oxygen conditions. Better quantifying warming contributions from the atmosphere, ocean, sea level, and rivers will also help constrain regional temperature projections throughout the estuary. More accurate projections of future Bay temperatures can help coastal managers better understand the potential for invasive species expansion and endemic species loss, impacts to fisheries and aquaculture, and how changes to ecosystem processes may impact coastal communities dependent on a healthy Bay.

Authors:
Kyle E. Hinson (Virginia Institute of Marine Science, William & Mary)
Marjorie A. M. Friedrichs (Virginia Institute of Marine Science, William & Mary)
Pierre St-Laurent (Virginia Institute of Marine Science, William & Mary)
Fei Da (Virginia Institute of Marine Science, William & Mary)
Raymond G. Najjar (The Pennsylvania State University)

Nutrient management improves hypoxia in the Chesapeake Bay despite record-breaking precipitation and warming

Posted by mmaheigan

· Friday, August 26th, 2022

Hypoxia is currently one of the greatest threats to coastal and estuarine ecosystems around the world, and this threat is projected to get worse as waters warm and human populations continue to increase. Over the past 35-years, a massive effort has been underway to decrease hypoxia in the Chesapeake Bay by reducing nutrient input from land. Despite this effort, record-breaking precipitation in 2018-2019 fueled particularly large hypoxic volumes in the Bay, calling into question the efficacy of management actions.

Figure 1. The number of days of additional hypoxia (O2 < 3 mg L^-1) that would have occurred in the Chesapeake Bay if the 35 years of nutrient reductions never occurred, as calculated by differences between a realistic numerical model simulation and one with 1985 nitrogen levels. This management effort has had the greatest impact at the northern and southern edges of the hypoxia in the Bay, where there would have been an additional 60-90 days of O2 < 3 mg L^-1 if nutrient reductions never occurred.

In a recent paper published in Science of the Total Environment, researchers used empirical and numerical modeling to quantify the impact of nutrient management efforts on hypoxia in the Chesapeake Bay. Results suggest that if the nutrient reduction efforts beginning in 1985 had not taken place, hypoxia would have been ~50–120% greater during the average discharge years of 2016–2017 and ~20–50% greater during the wet years of 2018–2019. The management impact was most pronounced in regions of the Bay where the hypoxia season would have been 60-90 days longer if nutrient reductions did not occur (Figure 1).

Although these results suggest that management has reduced hypoxic conditions in the Bay, additional analysis revealed that warming temperatures have already offset 6-34% of this improvement. This highlights the importance of factoring in climate change when setting future management goals.

Figure 2. The number of days of additional hypoxia (O2 < 3 mg L^-1) that would have occurred in the Chesapeake Bay if the 35 years of nutrient reductions never occurred, as calculated by differences between a realistic numerical model simulation and one with 1985 nitrogen levels. This management effort has had the greatest impact at the northern and southern edges of the hypoxia in the Bay, where there would have been an additional 60-90 days of O2 < 3 mg L^-1 if nutrient reductions never occurred.

Authors:
Luke T. Frankel (Virginia Institute of Marine Science, William & Mary)
Marjorie A. M. Friedrichs (Virginia Institute of Marine Science, William & Mary)
Pierre St-Laurent (Virginia Institute of Marine Science, William & Mary)
Aaron J. Bever (Anchor QEA)
Romuald N. Lipcius (Virginia Institute of Marine Science, William & Mary)
Gopal Bhatt (Pennsylvania State University; Chesapeake Bay Program)
Gary W. Shenk (USGS; Chesapeake Bay Program)

Why are sand lance embryos so sensitive to future high CO2-oceans?

Posted by mmaheigan

· Friday, August 26th, 2022

Two decades of ocean acidification experiments have shown that elevated CO₂ can affect many traits in fish early life stages. Only few species, however, show direct CO₂-induced survival reductions. This may partly reflect a bias in our current empirical record, which is dominated by species from nearshore tropical-to-temperate environments. There, these organisms already experience highly variable CO₂ conditions. In contrast, fishes from more offshore habitats, especially at higher latitudes are adapted to more CO₂-stable conditions, which could make them more CO₂-sensitive. This group of fishes is still underrepresented in the literature, despite its enormous commercial and ecological importance.

To help address this gap, we conducted new experimental work on northern sand lance Ammodytes dubius, a key forage fish on offshore Northwest Atlantic sand banks with trophic links to more than 70 different predator species of fish, squid, seabirds, and marine mammals. On Stellwagen Bank in the southern Gulf of Maine, sand lance are the ‘backbone’ of the eponymous National Marine Sanctuary.

We followed up on the intriguing findings of a pilot study a few years ago. Over two years and two trials, we again produced embryos from wild, Stellwagen Bank spawners and reared them at several pCO₂ levels (~400−2000 μatm) in combination with static and dynamic temperatures. Again, we observed consistently large CO₂-induced reductions in hatching success (-23% at 1,000 µatm, -61% at ~2,000 µatm), but this time the effects were temperature-independent.

Intriguingly, we again saw that many sand lance embryos at high CO₂ treatments did not merely arrest in their development (indicative of acidosis), but appeared to develop fully to hatch but were somehow incapable of doing so. We show several lines of evidence supporting the hypothesis that CO₂ directly impairs hatching in this species. Most fish rely on hatching enzymes that help embryos break the chorion (egg shell), but these ubiquitous enzymes may work less efficiently under high CO₂, low pH conditions.

For additional context, we also derived long-term, seasonal pCO₂ projections specifically for Stellwagen Bank, which together with the experimental data suggested that increasing CO₂ levels alone could reduce sand lance hatching success to 71% of contemporary levels by the year 2100.

We believe that the importance of sand lances as forage fishes across most northern hemisphere shelf ecosystem warrants a strategic effort of OA researchers to begin testing other sand lance species or populations to understand the magnitude of the problem and its underlying mechanisms.

Authors:
Hannes Baumann (University of Connecticut)
Lucas Jones (University of Connecticut)
Christopher Murray (University of Washington)
Samantha Siedlecki (University of Connecticut)
Michael Alexander (NOAA Physical Sciences Laboratory)
Emma Cross (Southern Connecticut State University)

What can algae tell us about translating laboratory science to nature?

Posted by mmaheigan

· Thursday, June 9th, 2022

Ocean acidification research has grown over the past few decades. Much of recent research documents negative impacts of changing carbonate chemistry on calcifying marine organisms in laboratory experiments. At the 2018 Ocean Acidification PI Meeting, a group of us asked “Can these laboratory responses to ocean acidification be scaled up to accurately predict the responses of marine ecosystems?” To answer this research question, we developed a semi-quantitative synthesis of benthic calcifying algae responses to ocean acidification, recently published in the ICES Journal of Marine Science.

Figure 1. Comparing directional responses of individuals and communities to acidification in laboratory and field settings highlights mismatches. Specifically, field studies document higher proportion of negative responses compared to laboratory experiments. We provide a series of recommendations for future research to better bridge this gap of understanding in responses to ocean acidification. Figure modified from Page et al. 2022.

We detail in the paper how the proportion of positive, neutral, and negative responses in laboratory experiments often didn’t match field observations. Additionally, laboratory experiments mainly report short-term responses (days to weeks) across tropical and temperate locations. In contrast, field studies emphasize long-term responses (months to years) from fewer global locations. Using our synthesis, we developed nine recommendations that will enhance our ability to translate laboratory experiment results into actual responses of marine taxa to ongoing and future acidification in the natural environment. These future research directions are applicable not only to ocean acidification studies but can be directly applied to the broader field of climate change. We hope these recommendations will lead to greater confidence in our projections of climate change impacts at different ecological scales, and better inform the conservation and management of our valuable marine ecosystems.

Backstory

Initially, we set out to answer this research question through a meta-analysis comparing the effect size of the impacts of ocean acidification on benthic calcifying macroalgae in laboratory and field settings. We quickly realized this approach was not going to work because of the much smaller number of responses recorded in field settings, the different methods used, and response parameters measured between the laboratory and field; these differences made calculating and comparing effect sizes impossible. Therefore, we landed on the approach of conducting a semi-quantitative synthesis to compare directional responses in laboratory and field settings. The results of this synthesis and the process of developing a robust research approach to answer our question inspired us to discuss and develop the recommendations for future research presented in the paper.

Authors (affils and Twitter handles)
Heather N. Page (Sea Education Association) @heathernicopage
Keisha D. Bahr (Texas A&M University – Corpus Christi) @thebahrlab
Tyler Cyronak (Nova Southeastern University) @tcyronak
Elizabeth B. Jewett (National Oceanic and Atmospheric Administration) @LibbyJewett
Maggie D. Johnson (King Abdullah University of Science and Technology) @MaggieDJohnson
Sophie J. McCoy (University of North Carolina at Chapel Hill) @MarEcology

Predators Set Range for the Ocean’s Most Abundant Phytoplankton

Posted by mmaheigan

· Friday, April 1st, 2022

Prochlorococcus is the world’s smallest phytoplankton (microscopic plant-like organisms) and the most numerous, with more than ten septillion individuals. This tiny plankton lives ubiquitously in warm, blue, tropical waters but is conspicuously absent in more polar regions. The prevailing theory was the cold: Prochlorococcus doesn’t grow at low temperatures. In a recent paper, the authors argue ecological control, in particular, predation by zooplankton. Cold polar waters are greener because they contain more nutrients, leading to more life and more organic matter production. This production feeds more and larger heterotrophic bacteria, who then feed larger predators—specifically the same zooplankton that consume Prochlorococcus. If the shared zooplankton increases enough, it will consume Prochlorococus faster than it can grow, causing the species to collapse at higher latitudes. These results show that an understanding of both ecology and temperature is required to predict how these ecosystems will shift in a warming ocean.

Figure 1: Surface populations of Prochlorococcus collapse (dashed lines) moving northward from Hawaii as seen in transects (transect line shown in red on map, lower left) from cruises in April 2016 (black dots) and September 2017 (green triangles). This collapse of the Prochlorococcus emerges in dynamical computer models (lower right, color indicates Prochlorococcus biomass in mgC/m3) when heterotrophic bacteria and Prochlorococcus share a grazer (top schematic). Increased organic production heading poleward first increases the heterotrophic bacterial population, increasing the shared zooplankton population which eventually consumes Prochlorococcus faster than it can grow (dashed contour).

Authors
Christopher L. Follett (MIT)
Stephanie Dutkiewicz (MIT)
François Ribalet (UW)
Emily Zakem (USC)
David Caron (USC)
E. Virginia Armbrust (UW)
Michael J. Follows (MIT)

Zooplankton evolutionary rescue is limited by warming and acidification interactions

Posted by mmaheigan

· Friday, November 19th, 2021

A key issue facing ocean global change scientists is predicting the fate of biota under the combined effects of ocean warming and acidification (OWA). In addition to the constraints of studying multifactor drivers, predictions are hampered by few evolutionary studies, especially for animal populations. Evolutionary studies are essential to assess the possibility of evolutionary rescue under OWA– the recovery of fitness that prevents population extirpation in the face of environmental change.

Figure 1. Population fitness of the copepod Acartia tonsa vs generation under ambient, AM (18^oC, 400 µat pCO₂), ocean warming, OW (22^oC, 400 µat pCO₂), ocean acidification, ocean acidification (18^oC, 2000 µat pCO₂), and ocean warming and acidification ( 22^oC, 2000 µat pCO₂). Shown are means and 95% confidence intervals around the mean. The purple line shows that while fitness decreased after the 12^th generation, it was still considerably higher than at generation zero. Treatment lines are offset for clarity. N_o and N_τ (Y-axis legend) represent population size at the beginning and end of a generation (τ), and their ratio is the population fitness. Adapted from Dam et al. (2021).

A paper by Dam et al. published in Nature Climate Change examined the response of a ubiquitous copepod (zooplankter) to OWA for 25 generations to test for evolutionary rescue (Fig. 1). Using a suite of life-history traits, the researchers determined population fitness (the net reproductive rate per generation) under ambient, ocean warming, ocean acidification and OWA conditions. While population fitness decreased drastically under OWA conditions, it recovered in a few generations. However, after 12 generations under OWA, in contrast to OW or OA, fitness started to decrease again, suggesting incomplete evolutionary rescue driven by antagonistic interactions between warming and acidification. Such interactions add complexity to predictions of the fate of the oceanic biota under climate change.

Limited copepod evolutionary rescue would mean lower fisheries yields under OWA conditions as copepods are a main food source for forage fish. Copepods are also important vectors of the sequestration of CO₂ to deeper waters of the ocean. Limited copepod adaptation under OWA could weaken the efficiency of the biological carbon pump.

Authors:
Hans G. Dam (University of Connecticut)
James de Mayo (University of Connecticut)
Gihong Park (University of Connecticut)
Lydia Norton (University of Connecticut)
Xuejia He (Jinan University, China)
Michael B. Finiguerra (University of Connecticut)
Hannes Baumann (University of Connecticut)
Reid S. Brennn (University of Vermont)
Melissa H. Pespeni (University of Vermont)

Contrasting N2O fluxes of source vs. sink in western Arctic Ocean during summer 2017

Posted by mmaheigan

· Wednesday, October 20th, 2021

During the western Arctic summer season both physical and biogeochemical features differ with latitude between the Bering Strait and Chukchi Borderland. The southern region (Bering Strait to the Chukchi Shelf) is relatively warm, saline, and eutrophic, due to the intrusion of Pacific waters that bring heat and nutrients in to the western Arctic Ocean (WAO). Because of the Pacific influence, the WAO is one of the most productive stretches of ocean in the world. In contrast, the northern region (Chukchi Borderland to the Canada Basin) is primarily influenced by freshwater originating from sea ice melt and rivers, and is relatively cold, fresh, and oligotrophic. A frontal zone exists between the southern region and northern region (~73°N) due to the distinct physicochemical contrast between mixing Pacific waters and freshwater. These regions support distinct bacterial communities also, making the environmental variations drivers extremely relevant to nitrous oxide (N₂O) dynamics.

A recent study published in Scientific Reports examined the role of the WAO as a source and a sink of atmospheric N₂O. There are obvious differences in N₂O fluxes between southern Chukchi Sea (SC) and northern Chukchi Sea (NC). In the SC (Pacific water characteristics dominate) N₂O emissions act as a net source to the atmosphere (Figure 1a). In the NC (freshwater dominant) absorption of atmospheric N₂O into the water column suggests that this region acts as a net sink (Figure 1a). The positive fluxes of SC occurred with relatively high sea surface temperature (SST), sea surface salinity (SSS), and biogeochemically-derived N₂O production, whereas the negative fluxes of NC were associated with relatively low SST, SSS, and little N₂O production. These linear relationships between N₂O fluxes and environmental variables suggest that summer WAO N₂O fluxes are remarkably sensitive to environmental changes.

Figure 1. (a) Map of the sampling stations using the Ice Breaking R/V Araon during August 2017. The sampling locations were coloured with N2O fluxes (blue to red gradient, see color bar; sink, air → sea (−), and source, sea → air (+). The southern Chukchi Sea (SC) extends from Bering Strait to Chukchi Shelf and the northern Chukchi Sea (NC) extends from Chukchi Borderland and Canada Basin. The frontal zone arises between SC and NC (black dotted line). (b) Illustration showing future changes in the distribution of the WAO N2O flux constrained by the positive feedback scenario of increasing inflow of Pacific waters and rapidly declining sea-ice extent under accelerating Arctic warming.

This study suggests a potential scenario for future WAO changes in terms of accelerating Arctic change. Increasing inflow of the Pacific waters and rapidly declining sea-ice extent are critical. The increasing inflow of warm nutrient-enriched Pacific waters will likely extend the SC N₂O source region northward, increasing productivity, and thereby intensifying nitrification. All of which would lead to a strengthening of the WAO’s role as an N₂O source. A rapid loss of the sea ice extent could ultimately lead to a sea-ice-free NC, and again, a northward shift, which would result in a diminished role of the NC as an N₂O sink (Figure 1b). While improving our understanding of WAO N₂O dynamics, this study suggests both a direction for future work and a clear need for a longer-term study to answer questions about both seasonal variations in these dynamics and possible interannual to climatological trends.

Authors:
Jang-Mu Heo (Department of Marine Science, Incheon National University)
Sang-Min Eom (Department of Marine Science, Incheon National University)
Alison M. Macdonald (Woods Hole Oceanographic Institution)
Hyo-Ryeon Kim (Department of Marine Science, Incheon National University)
Joo-Eun Yoon (Department of Marine Science, Incheon National University)
Il-Nam Kim (Department of Marine Science, Incheon National University)

Species loss alters ecosystem function in plankton communities

Posted by mmaheigan

· Monday, February 8th, 2021

Climate change impacts on the ocean such as warming, altered nutrient supply, and acidification will lead to significant rearrangement of phytoplankton communities, with the potential for some phytoplankton species to become extinct, especially at the regional level. This leads to the question: What are phytoplankton species’ redundancy levels from ecological and biogeochemical standpoints—i.e. will other species be able to fill the functional ecological and/or biogeochemical roles of the extinct species? Authors of a paper published recently in Global Change Biology explored these ideas using a global three-dimensional computer model with diverse planktonic communities, in which single phytoplankton types were partially or fully eliminated. Complex trophic interactions such as decreased abundance of a predator’s predator led to unexpected “ripples” through the community structure and in particular, reductions in carbon transfer to higher trophic levels. The impacts of changes in resource utilization extended to regions beyond where the phytoplankton type went extinct. Redundancy appeared lowest for types on the edges of trait space (e.g., smallest) or those with unique competitive strategies. These are responses that laboratory or field studies may not adequately capture. These results suggest that species losses could compound many of the already anticipated outcomes of changing climate in terms of productivity, trophic transfer, and restructuring of planktonic communities. The authors also suggest that a combination of modeling, field, and laboratory studies will be the best path forward for studying functional redundancy in phytoplankton.

Figure caption: Examples of the modelled ecological and biogeochemical responses to the extinction of different phytoplankton species.Figure caption: Examples of the modelled ecological and biogeochemical responses to the extinction of different phytoplankton species.

Authors:
Stephanie Dutkiewicz (Massachusetts Institute of Technology)
Philip W. Boyd (Institute for Marine and Antarctic Studies, University of Tasmania)
Ulf Riebesell (GEOMAR Helmholtz Centre for Ocean Research Kiel)

How environmental drivers regulated the long-term evolution of the biological pump

Posted by mmaheigan

· Friday, January 22nd, 2021

The marine biological pump (BP) plays a crucial role in regulating earth’s atmospheric oxygen and carbon dioxide levels by transferring carbon fixed by primary producers into the ocean interior and marine sediments, thereby controlling the habitability of our planet. The rise of multicellular life and eukaryotic algae in the ocean about 700 million years ago would likely have influenced the physical characteristics of oceanic aggregates (e.g., sinking rate), yet the magnitude of the impact this biological innovation had on the efficiency of BP is unknown.

Figure. 1. The impact of biological innovations (left) and environmental factors (atmospheric oxygen level and seawater temperature; right) on the efficiency of marine biological pump (BP). Temperatures are ocean surface temperatures (SST), and atmospheric pO2 is shown relative to the present atmospheric level (PAL). The BP efficiency is calculated as the fraction of carbon exported from the surface ocean that is delivered to the sediment-water interface. The results indicate that evolution of larger sized algae and zooplanktons has little influence on the long-term evolution of biological pump (left panel). The change in the atmospheric oxygen level and seawater surface temperature as environmental factors, on the other hand, have a stronger leverage on the efficiency of biological pump (right panel).

The authors of a recent paper in Nature Geoscience constructed a particle-based stochastic model to explore the change in the efficiency of the BP in response to biological and physical changes in the ocean over geologic time. The model calculates the age of organic particles in each aggregate based on their sinking rates, and considers the impact of primary producer cell size, aggregation, temperature, dust flux, biomineralization, ballasting by mineral phases, oxygen, and the fractal geometry (porosity) of aggregates. The model results demonstrate that while the rise of larger-sized eukaryotes led to an increase in the average sinking rate of oceanic aggregates, its impact on BP efficiency was minor. The evolution of zooplankton (with daily vertical migration in the water column) had a larger impact on the carbon transfer into the ocean interior. But results suggest that environmental factors most strongly affected the marine carbon pump efficiency. Specifically, increased ocean temperatures and greater atmospheric oxygen abundance led to a significant decrease in the efficiency of the BP. Cumulatively, these results suggest that while major biological innovations influenced the efficiency of BP, the long-term evolution of the marine carbon pump was primarily controlled by environmental drivers such as climate cooling and warming. By enhancing the rate of heterotrophic microbial degradation, our results suggest that the anthropogenically-driven global warming can result in a less efficient BP with reduced power of marine ecosystem in sequestering carbon from the atmosphere.

Authors:
Mojtaba Fakhraee (Yale University, Georgia Tech, and NASA Astrobiology Institute)
Noah J. Planavsky (Yale University, and NASA Astrobiology Institute)
Christopher T. Reinhard (Georgia Tech, and NASA Astrobiology Institute)

Climate-driven pelagification of marine food webs: Implications for marine fish populations

Posted by mmaheigan

· Friday, January 22nd, 2021

Global warming changes the conditions for all ocean life, with wide-ranging consequences. It is particularly difficult to predict the impact of climate change on fish because fish production is conditioned on both temperature and food resource (zooplankton and benthic organisms) changes. Climate change projections from Earth system models show a negative amplification of changes in global ocean net primary production (NPP), with an approximate doubling of production decreases from net primary producers to mesozooplankton. This “trophic amplification” continues up the marine food web to fishes. A new study published in Frontiers in Marine Science illustrates this amplification clearly when fishes are defined by their maximum body size, which describes their position in the food web (Figure 1a). However, decreases in globally integrated biomass and production were not limited to differences in size alone. Importantly, reduced abundances also varied by fish functional type (Figure 1b).

Figure 1: a) Percent change in net primary production (NPP), mesozooplankton (MesoZ) production, all medium (M) fishes, and all large (L) fishes from Historic (1951-2000) to the RCP 8.5 Projection (2051-2100). b) Percent change in production of forage fish, large pelagic fish, demersal fish, and benthic invertebrates in Projection (2051-2100) from Historic (1951-2000). c) Absolute change in the ratio of zooplankton production to seafloor detrital flux as the difference of the Projection (2051-2100) from the Historic (1951-2000). d) Percent change in zooplankton production (dashed grey), percent change in seafloor detrital flux (solid grey), and absolute change in the ratio of their means during the Historic and Projection time periods relative to 1951.

Despite the “pelagification” of marine food webs caused by unequal decreases in secondary production (Figure 1d) and subsequent increases in pelagic zooplankton production relative to seafloor detritus production (Figure 1c,d), large pelagic fish (e.g., tunas and billfishes) suffered the greatest declines and the highest degree of projection uncertainty. The result was a shift from benthic-based ecosystems historically dominated by large demersal fish (e.g., cods and flounders) towards pelagic-based ones dominated by smaller forage fish (e.g., sardines and herring). Any positive impacts of the pelagification of food resources on large pelagic fish were overwhelmed by the negative impacts of the overall reduction in global productivity, compounded by warming-induced increases in metabolic demands. Both the degree of change in the productivity of large pelagic fish and the magnitude of trophic amplification were sensitive to the temperature dependence of metabolic rates. Thus, better constraints are needed on empirical estimates of the effect of temperature on physiological rates to project the impacts of climate change on fish biomass and marine ecosystem structure.

Ocean fish harvests currently supply ~15% of global protein demand. Reduced primary production will decrease the total amount of fish available to harvest for human food, while the pelagification of ecosystems could require large and expensive structural modifications to fisheries, including gear, location, regional and international management plans, consumer demands, and market values.

Authors:
Colleen M. Petrik (Texas A&M University)
Charles A. Stock (Geophysical Fluid Dynamics Laboratory)
Ken H. Andersen (Technical University of Denmark)
P. Daniël van Denderen (International Council for the Exploration of the Seas)
James R. Watson (Oregon State University)

Funding for the Ocean Carbon & Biogeochemistry Project Office is provided by the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA). The OCB Project Office is housed at the Woods Hole Oceanographic Institution.

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