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Author Archive for mmaheigan

The North Atlantic’s microscopic carbon traffic controllers

Posted by mmaheigan 
· Friday, August 14th, 2026 

Each year, as the North Atlantic transitions from turbulent spring mixing to layered summer stratification, a key question emerges: How do these seasonal changes reshape bacterial host-virus interactions and control carbon flux?

In a recent study published in Microorganisms, researchers show that seasonal stratification regulates viral activity by modulating encounter rates between viruses and distinct bacterial hosts. They found that one viral group (V1) is tightly coupled with high nucleic acid (HNA) bacteria in stratified surface waters, whereas another (V2) preferentially interacts with low nucleic acid (LNA) cells in the deeper, well-mixed layers. These patterns indicate that physical layering structures viral dynamics by regulating host distribution and ecological traits. Importantly, the study reveals a growth-dependent shift in viral infection strategy. The induction of temperate viruses increases with host growth rate up to a metabolic threshold (~0.1 d⁻¹), then declines as lytic infection becomes dominant. This finding challenges the traditional paradigm that lysogeny is favored under low-productivity conditions, instead suggesting that lysogeny may play a key role in fast-growing, r-selected host-virus systems.

These results highlight how viruses act as microscopic carbon traffic controllers, regulating the balance between microbial recycling and carbon export across seasonal transitions. During the shift toward stronger stratification, virus-driven lysis redirects up to 47% of bacterial carbon into dissolved pools each day, reinforcing the dominance of the microbial loop. Yet, under certain conditions, viral lysis may also inject carbon into deeper waters, enhancing export and the efficiency of the biological carbon pump. It is essential to understand these shifting pathways to predict how ocean stratification reshapes carbon cycling in a changing climate.

 

Authors:
Yean Das (The University of Southern Mississippi)
Corina P. D. Brussaard (NIOZ Royal Netherlands Institute for Sea Research & University of Amsterdam)
Kristina D. A. Mojica (The University of Southern Mississippi)

Citation:
Das, Y., Brussaard, C. P. D, & Mojica, K. D. (2025). Heterotrophic Prokaryote Host–Virus Dynamics During Spring in the Northeast Atlantic Ocean. Microorganisms, 13(11), 2474. https://doi.org/10.3390/microorganisms13112474

Impacts of warming and circulation slowdown on future ocean carbon cycle feedback

Posted by mmaheigan 
· Friday, August 14th, 2026 

The ocean has absorbed a quarter of anthropogenic CO2 emissions, mitigating changes. However, predicting the future fate of this ‘sink’ is challenging as marine carbon is regulated by a complex set of interacting processes that respond differently to warming. Our recent study teases apart these interactions with a novel mechanistic carbon decomposition and attribution framework applied to an ocean biogeochemical model driven by output from a climate model, to quantify the impact of changes in different forcing factors, such as warming and circulation, on marine carbon storage and the consequent feedback on atmospheric CO2.

Figure: (a) Waterfall chart attributing changes in atmospheric CO2 (pCO2atm) (relative to a simulation with no climate change; NCC) to different carbon components for the SSP5-8.5 high-emission scenario. Each bar represents a component with its height corresponding to the (positive or negative) change in pCO2atm due to that component. The cumulative change in pCO2atm as successive components are added is shown from left to right. Subscripts are: sat=saturation, dis=disequilibrium, soft=soft tissue remineralization, caco3=CaCO3 dissolution, phy=physical process, and bio=biological process. (b) Compensation ratio of change (∆) in preformed to regenerated carbon with respect to NCC in the Temperature (solid lines) and Circulation (dashed lines) attribution experiments for the four emission scenarios studied as a function of time. (c) Change in carbon components with respect to NCC in year 2500 due to temperature under the SSP1-2.6 low-emission scenario. (d) Change in carbon components with respect to NCC in year 2500 due to circulation under SSP5-8.5.

We find that under a high-emission scenario, global warming reduces marine carbon storage and raises atmospheric CO2 in 2500 by ~270 ppm (Fig panel a), a positive feedback. This is due to a decrease in ocean CO2 uptake (Csat,phy), compensated in part by an increase in biologically regenerated carbon (Csoft & Ccaco3). While previous studies have also found this compensation, they have ascribed it largely to a slowdown in ocean circulation. Our attribution experiments instead show that the degree of compensation depends strongly on the process and emission scenario (Panel b). Reduced CO2 uptake due to a slower circulation is half-compensated by increased regenerated carbon under high emissions, but almost exactly compensated for under the lowest emission scenario (dashed lines). On the other hand, temperature-driven changes in uptake and regeneration are mostly uncompensated (solid lines); the direct effects of warming thus dominate under low-emission, high-mitigation scenarios, while also contributing a third of the decrease in carbon storage at the highest emissions. Air-sea disequilibrium, as revealed by the carbon decomposition, provides an explanation. Warming enhances physical disequilibrium because of an increase in the meridional sea surface temperature gradient; this is the leading cause of the decrease in carbon storage under low emissions (Panel c). In contrast, for high emissions (Panel d) a slowdown in circulation decreases physical disequilibrium, amplifying the impact of increased biological carbon sequestration in compensating for reduced CO2 uptake. In summary, temperature dominates the climate-carbon cycle feedback for low emission scenarios, and circulation for high emission scenarios. This study provides new mechanistic insights into how the marine carbon cycle responds to change, and highlights the need for accurate partitioning of carbon components in Earth System Models.

 

Authors:
Samar Khatiwala (Waseda University)
Olivia Strachan (Independent Researcher)
Andreas Schmittner (Oregon State University)

Citation: Khatiwala, S., O. Strachan and A. Schmittner (2026). Multi-centennial response of marine carbon pumps to global warming, Nature Climate Change, https://doi.org/10.1038/s41558-026-02686-x.

Research Briefing (accompanying the main article): Warming dominates over circulation slowdown in reducing marine carbon storage under high-mitigation scenarios, Nature Climate Change, https://doi.org/10.1038/s41558-026-02687-w.

Do ecological feedbacks matter in a changing world?

Posted by mmaheigan 
· Friday, August 14th, 2026 

Interactions among organisms shape ecological dynamics, while exchanges with the environment alter physical and chemical conditions. Examples of these include predator-prey dynamics (biotic interaction), the release of nutrients through excretion (chemical changes), or the development of coral reefs (physical changes). Together, these processes can generate feedback loops, which may amplify or buffer the impacts of environmental change. We know such processes are important in ecosystems, but do ecological feedbacks really matter at larger scales and in the wider Earth system? To address this question, authors of a recent study published in Earth’s Future, compiled what is known about how ecological feedbacks operate, drawing on examples from ecosystems in marine, terrestrial and freshwater habitats across the world.

Figure caption: A wide range of ecological feedbacks influence the functioning of coral reef systems, affecting the structure and functioning of the ecosystem and associated physical and biogeochemical processes. Figure modified from Murphy et al. (2025), originally published in Earth’s Future, © The Authors, published by the American Geophysical Union under a Creative Commons license.

The synthesis highlights that ecological feedbacks are ubiquitous within and across ecosystems, yet remain a major gap in Earth system science. Ecological feedbacks can affect ecosystem structure and resilience, tipping points, global biogeochemical cycles, and the structure and dynamics of the physical environment. The study emphasises that current Earth System models often underrepresent these processes, despite their importance for carbon cycling, climate regulation, and ecosystem stability. Representing them appropriately is not trivial. Feedbacks operate across spatial (local to global) and temporal (seconds to centuries) scales, and are integral in multiple Earth system processes. A systematic approach is needed to both develop our understanding of ecological feedbacks and refine models, which will require increased integration of ecosystem and Earth system research. Overall, these findings matter because failing to account for ecological feedbacks could lead to inaccurate climate projections, misguided policy decisions, and unanticipated ecological losses.

Authors
Eugene Murphy (British Antarctic Survey)
Jessica Williams (Imperial College London)
Emma Cavan (Imperial College London)

 

Follow and learn more:
www.bas.ac.uk, IMBeR, ICED, SCOR, Future Earth, imber-youtube

@britishantarcticsurvey, @imber, @scor-int.bsky.social, @futureearth

https://www.bas.ac.uk/profile/ejmu/

https://profiles.imperial.ac.uk/jessica.williams15

https://profiles.imperial.ac.uk/e.cavan/about

 

Some extra background:
The study developed from scientific activities of the Integrating Climate Ecosystem Dynamics in the Southern Ocean (ICED) programme and the Integrated Marine Biosphere Research Project (IMBeR). ICED is a regional programme of IMBeR, which is a Large-Scale Ocean Research Project under the Scientific Committee on Oceanic Research (SCOR) and a Global Research Network under Future Earth. Improving understanding of ecological feedbacks in the Earth system was developed as an Innovation Challenge of IMBeR, with a conference session on the topic held at the Future Oceans 2 conference. Following subsequent discussions, and a recognition of the connected nature of ecosystems across the world, the study expanded to develop an integrated view encompassing marine, terrestrial and freshwater systems.

 

Citation: Murphy, E. J., Williams, J. J., Myers-Smith, I. H., Groner, V. P., Jacoby, D. M. P., Kwiatkowski, L., Melbourne-Thomas, J., Ransome, E., Banks-Leite, C., Bopp, L., Gehlen, M., Hofmann, E. E., Hoogakker, B., Johnston, N. M., Malhi, Y., & Cavan, E. L. (2026). Ecological Feedbacks in the Earth System. Earth’s Future, 14(2), e2025EF006478. https://doi.org/10.1029/2025EF006478

 

Beyond carbonate chemistry: Biogenic silica dissolution may weaken carbon sequestration under ocean alkalinity enhancement

Posted by mmaheigan 
· Friday, August 14th, 2026 

Ocean alkalinity enhancement (OAE) is a promising carbon dioxide removal strategy, yet evaluating its net carbon removal potential requires understanding not only seawater carbonate chemistry, but also biological feedbacks that may influence long-term carbon sequestration. While most OAE studies focus on resolving immediate responses during biomass production, much less attention is paid to processes occurring during particle sinking.

In a 39-day mesocosm experiment in the North Sea, a recent study investigated how phytoplankton bloom development and the composition of sinking particles responded to CO2-unequilibrated OAE (ΔTAmax = 1250 μmol kg-1). Although phytoplankton blooms were delayed, their overall magnitude and organic carbon export remained largely unchanged across the OAE gradient. In contrast, elevated pH (up to 9.25) enhanced the dissolution of diatom-derived silica during particle sinking, reducing silica ballasting ratios (BSi:POC) by up to 60%. This response is consistent with the well-established pH sensitivity of biogenic silica dissolution. Following bloom senescence, the degradation of protective organic coatings surrounding diatom frustules exposes biogenic silica to naturally undersaturated seawater, where elevated pH further accelerates dissolution.

Figure caption: A conceptual illustration of the North Sea mesocosm experiment investigating CO₂-unequilibrated OAE across a broad alkalinity gradient generated through different dilution scenarios. Original treatment colours and symbols are retained for transparency, although dilution treatments were pooled for the final analysis. Elevated pH enhanced the dissolution of diatom-derived biogenic silica during particle sinking, reducing silica ballasting ratuis (BSi:POC). The inset compares bloom-averaged water column (dashed regression, R2 = 0.56, p < 0.01) and deposition-averaged sediment trap (solid regression, R2 = 0.74, p < 0.01) silica ballasting ratios, illustrating that silica loss intensified during particle sinking. Graphics adapted from Integration and Application Network, University of Maryland Center for Environmental Science, https://ian.umces.edu/symbols/.

Because silica ballasting influences the depth at which sinking organic matter is remineralized, reduced silica preservation may shoal carbon remineralization and shorten carbon sequestration timescales, even when export production remains unchanged. The study highlights an export-phase process that has received little attention in OAE research and should be considered in future field observations and Earth system models evaluating the net carbon sequestration efficacy of OAE.

Authors
Philipp Suessle (University of the Azores)
Kai Georg Schulz (Southern Cross University, Geomar Helmholtz-Centre for Ocean Research)
Joana Barcelos e Ramos (University of the Azores)
Nico Manuel Sievers (Geomar Helmholtz-Centre for Ocean Research)
Julieta Schneider (Southern Cross University, Geomar Helmholtz-Centre for Ocean Research)
Juliane Katharina Tammen (Geomar Helmholtz-Centre for Ocean Research)
Leila Kittu (Geomar Helmholtz-Centre for Ocean Research)
Laura Marín-Samper (University of Las Palmas de Gran Canaria)
Maarten Boersma (Alfred-Wegener-Institute, Helmholtz-Centre for Polar- and Marine Research)
Ulf Riebesell (Geomar Helmholtz-Centre for Ocean Research)

 

Citation: Suessle, P., Schulz, K. G., Barcelos e Ramos, J., Sievers, N. M., Schneider, J., Tammen, J. K., Kittu, L., Marín-Samper, L., Boersma, M., and Riebesell, U. (2026) Ocean alkalinity enhancement reduces silica ballasting during export due to amplified dissolution, Biogeosciences, 23, 4691–4710, https://doi.org/10.5194/bg-23-4691-2026.

BGC-Argo floats reveal shifting nitrogen cycling in the Eastern Tropical North Pacific

Posted by mmaheigan 
· Friday, August 14th, 2026 

Oxygen-deficient zones are regions of the ocean where microbes consume nitrate in lieu of oxygen. This drives major losses of biologically available nitrogen. In a recent study, we used a BGC-Argo float in the Eastern Tropical North Pacific to remotely observe these processes over nearly three years. Using a new method to extract nitrite from UV nitrate sensor spectra (Bif and Johnson, 2025), the float captured a progressive decline in the secondary nitrite maximum over time, revealing a shift in microbial nitrogen cycling through time.

By combining float observations with a stoichiometric biogeochemical model, we found that nitrogen transformations reorganized in response to changing organic matter supply and redox conditions. The results show that oxygen-deficient zones are highly dynamic environments rather than stable systems. This also demonstrates how autonomous observing platforms can now monitor hidden nitrogen and carbon cycling processes across the global ocean in near real time.

Figure. BGC-Argo float observations in the Eastern Tropical North Pacific oxygen-deficient zone. (a) Float WMO#5906484 trajectory. (b) Time-series distribution of nitrite concentrations. The white contour indicates the upper boundary of low-oxygen waters of less than 1 µmol/kg. (c) Nitrate concentrations over the same period. (d–e) Relative contributions of anammox and denitrification estimated with a stoichiometric mass-balance model under contrasting biogeochemical conditions.

Authors:
Mariana B. Bif (University of Miami)
Colette Kelly (Woods Hole Oceanographic Institution, now
Mark A. Altabet (University of Massachusetts Dartmouth)
Annie Bourbonnais (University of South Carolina)
Claire Elbon (University of Washington)
Edgart Flores (University of Colorado Boulder
Alanna Mnich (University of Massachusetts Dartmouth)
Josh Plant (Monterey Bay Aquarium Research Institute (MBARI))
Kenneth S. Johnson (Monterey Bay Aquarium Research Institute (MBARI))

 

 

Citations:

Bif, M.B., & Johnson, K.S., 2025. BGC-Argo floats reveal nitrite and thiosulfate dynamics in the oceans with high spatiotemporal resolution. Global Biogeochemical Cycles, 39, e2024GB008473. https://doi.org/10.1029/2024GB008473

Bif, M.B., Kelly, C., Altabet, M.A., Bourbonnais, A., Elbon, C., Flores, E., Mnich, A., Plant, J. and Johnson, K.S., 2026. BGC-Argo float reveals shifts in nitrogen-carbon cycling in an oxygen-deficient zone. Communications Earth & Environment, 7(1), p.294. https://www.nature.com/articles/s43247-026-03410-5

Remembering Dr. Jorge Sarmiento

Posted by mmaheigan 
· Friday, July 10th, 2026 

The global climate science community mourns the passing of Dr. Jorge Sarmiento in May 2026. In addition to co-authoring the first decadal U.S. Carbon Cycle Science Plan (Sarmiento and Wofsy, 1999) and leading the historic push to develop the U.S. Carbon Cycle Science Program and its carbon science coordination entities, OCB and NACP,  Jorge stood as a pioneering “giant” in ocean biogeochemistry whose visionary leadership fundamentally shaped the trajectory of Earth system science. From his early steering of JGOFS to his profound contributions within OCB and his groundbreaking work heading the SOCCOM initiative, Jorge unraveled the critical complexities of the Southern Ocean and global marine ecosystems. Yet, beyond his extraordinary scientific accolades, including his shared recognition in the 2007 Nobel Peace Prize, his ultimate legacy lives on through his selfless mentorship, his infectious enthusiasm for new ideas, and the generations of brilliant scientists he inspired and guided. We owe an immeasurable debt of gratitude to Jorge for his career of profound discovery, collaborative spirit, and enduring dedication to understanding our planet. He will be deeply missed, but his scientific legacy remains a guiding light for all future carbon cycle research. 

See also ‘Remembering Jorge Sarmiento, a ‘giant’ in climate studies’

GLODAPv3 – A new version release

Posted by mmaheigan 
· Wednesday, July 8th, 2026 

On behalf of the GLODAP Reference Group and hundreds of seagoing oceanographers who have tirelessly collected data all over the ocean for several decades, it is our pleasure to announce the release of the new Global Ocean Data Analysis Project version 3, GLODAPv3!

Use this link for direct access: GLODAPv3 OCADS landing page and check out our webpage.

GLODAPv3 provides surface-to-bottom ocean biogeochemical observations determined through chemical analysis of discrete bottle samples. This new version comprises data from 1181 cruises, spanning more than 50 years of observations (1972 – 2023). It includes all data from the previous GLODAPv2.2023, together with an additional 57 new cruises. All data have been evaluated for systematic differences and adjusted appropriately. The result is the most comprehensive and rigorously quality controlled ocean interior data product for marine biogeochemistry studies. Its analysis will allow for quantitative assessment of biogeochemical changes and feedbacks between climate change and the ocean.

          GLODAPv3 Cruises

 

GLODAPv3 consists of:

  • a data base with original cruise data, as submitted by individual data providers but updated to WOCE Exchange format
  • a merged data product, with systematic measurement differences removed for key biogeochemical variables

The original data, their documentation and DOIs are available at the Ocean Carbon Data System of NOAA NCEI.

GLODAPv3 is the result of a multi-year global team effort funded by the EU Horizon Europe project OceanICU, US NOAA, the SCOR-IOC International Ocean Carbon Coordination Project (IOCCP) and many other projects, programmes and organisations.

 

The procedures and results are extensively documented in:

  • Nico Lange, Siv K. Lauvset, Brendan R. Carter, Matthew P. Humphreys, Ryan J.  Woosley, Are Olsen, Henry C. Bittig, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Susan Becker, Peter J. Brown, Leticia Cotrim da Cunha, Larissa Dias, Mario Hoppema, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Adam Ulfsbo, Anton Velo, and Toste Tanhua. Submitted.
  • Matthew P. Humphreys, Siv K. Lauvset, Nico Lange, Henry C. Bittig, Brendan R. Carter, Mario Hoppema, Akihiko Murata, Are Olsen, Toste Tanhua, Adam Ulfsbo, Antón Velo, Ryan J. Woosley, Kumiko Azetsu-Scott, Jens D. Müller, and Fiz F. Pérez. 2026.
    https://doi.org/10.5194/egusphere-2026-3063

This work was funded by the European Union under grant agreement no. 101083922 (OceanICU) and UK Research and Innovation (UKRI) under the UK government’s Horizon Europe funding guarantee [grant number 10054454, 10063673, 10064020, 10059241, 10079684, 10059012, 10048179]. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or European Research Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.

 

Phytoplankton respond more consistently to nutrient pulses than marine heat waves

Posted by mmaheigan 
· Monday, June 29th, 2026 

How do phytoplankton respond to short-term changes in temperature and nutrient availability, and how does this response vary under different baseline conditions?

A recent study perturbed a summer plankton community by manipulating nutrient concentrations and temperature (±4°C) in short-term controlled microcosms to assess the relative impacts of each factor on phytoplankton physiology and community structure. Nutrient amendments rapidly shifted the phytoplankton community towards larger cells, altered elemental stoichiometry, and reduced microzooplankton grazing. Conversely, temperature changed community composition, but had no impact on size or stoichiometry. These results paralleled a similar spring incubation and regional field studies, which together suggest that over short time scales (days) nutrient amendments may produce more consistent and significant impacts on phytoplankton composition and physiology than temperature or grazing. Though temperature is a significant driver of phytoplankton dynamics globally, the impacts of short-term temperature changes, like marine heat waves, may depend on baseline thermal conditions, the starting plankton community, and the availability of nutrients to cope with increased metabolic demands. Understanding baseline conditions will be central to deciphering how short-term temperature changes may impact phytoplankton communities and the ecosystems they support.

Figure caption. Illustrative diagram showing the impacts of short-term nutrient amendments on phytoplankton communities, and the factors that influence the thermal response. Frequency distribution plots show how the community size structure <20 µm differed between the nutrient amended treatment (solid) and the control (white) on day 4 of the incubation experiments, as discerned via flow cytometry forward scatter (FSC).

Authors
Stephanie I. Anderson (University of Rhode Island)
Gayantonia Franzè (University of Rhode Island & Institute of Marine Research)
Joshua D. Kling (University of Southern California)
Paul Wilburn (Michigan State University)
Colin T. Kremer (University of Connecticut)
Susanne Menden-Deuer (University of Rhode Island)
Elena Litchman (Michigan State University)
David A. Hutchins (University of Southern California)
Tatiana A. Rynearson (University of Rhode Island)

Bluesky
@drplankton.bsky.social
@quant-ecology.bsky.social
@elenalitchman.bsky.social
@stephanieianderson.bsky.social

Detecting the ocean’s eddy carbon pump globally—it’s smaller than we thought.

Posted by mmaheigan 
· Monday, June 29th, 2026 

How much carbon do ocean eddies actually pump into the ocean interior? A decade ago, a landmark study (Omand et al, 2015) showed that turbulent eddies at ocean fronts can grab carbon-rich surface water and plunge it hundreds of meters down in a matter of days—back-of-the-envelope extrapolations suggest this “eddy subduction pump” could export as much as 2 Pg of carbon per year (Boyd et al, 2019), roughly a fifth of the entire biological carbon pump. But because these events are small, short-lived, and scattered across every ocean basin, constraining the pump’s true size at the global scale has remained elusive. The authors of a recent study built an algorithm that detects individual subduction events from coincident anomalies in salinity, oxygen, and particulate organic carbon, and applied this algorithm to 126,591 profiles from 941 BGC-Argo floats, identifying 1,333 carbon subduction events concentrated in springtime hotspots in the Southern Ocean and the subpolar North Atlantic. The resulting global export below 200 m is about 0.05 [<0.01–0.28] Pg C yr⁻¹, orders of magnitude smaller than the earlier upper bound, and less than 5% of the total biological pump. The result is in close agreement with an independent global estimate derived from a four-dimensional POC budget (Bellacicco et al., 2025), giving us added confidence that the pump’s true magnitude is modest. This is, somewhat counterintuitively, reassuring news for global carbon budgets. Current Earth System Models cannot resolve the kilometer-scale dynamics behind eddy subduction, but our results suggest they are not missing a first-order term in the ocean carbon cycle.

Figure caption : Spatial distribution of total annual mean POC flux below 200 m from the eddy subduction pump, assuming a constant vertical velocity W = 200 m day⁻¹. Strongest export occurs in the Southern Ocean and subpolar North Atlantic. White stippling marks 5° grid cells without Argo profiles (insufficient coverage).

 

Authors
Maxime Keutgen De Greef
Laure Resplandy
Mathieu A. Poupon
(all Princeton Univ)

Celebrating 20 years of OCB + OCB2027 dates

Posted by mmaheigan 
· Monday, June 22nd, 2026 

Save the dates for OCB2027 in person June 22-25, 2027

2026 marks 20 years since the OCB Project Office began in 2006 to support science, community, and connection across a globally distributed network of scientists! To celebrate all the accomplishments of the community across these two decades, OCB is convening a one-day virtual symposium on November 18, 2026. The symposium will highlight scientific discoveries, game-changing technologies, and lessons learned from the perspective of OCB community members.

This 20th anniversary symposium will feature the following four topics, which have seen a lot of growth in OCB, particularly in the last decade:

  • Air-Sea Interactions 
  • Biological Carbon Pump
  • Ocean Carbon Removal
  • Ocean Metabolism (featuring programmatic developments across GEOTRACES, OCB, and the newly emerging BioGeoSCAPES)

Speakers and panelists will be announced soon.

The November 18 event will start at 11 am (Eastern Standard Time) and run approx. 7 hours with numerous breaks.

Learn more and register

 

 

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primary productivity new ocean state new technology Niskin bottle nitrate nitrogen nitrogen cycle nitrogen fixation nitrous oxide north atlantic north pacific North Sea NPP nuclear war nutricline nutrient budget nutrient cycles nutrient cycling nutrient limitation nutrients OA observations ocean-atmosphere ocean acidification ocean acidification data ocean alkalinity enhancement ocean carbon uptake & storage ocean carbon uptake and storage ocean color ocean interior ocean modeling ocean observatories ocean warming ODZ oil oligotrophic omics OMZ open ocean optics organic carbon organic particles oscillation outwelling overturning circulation oxidizing oxygen oxygen-deficient pacific paleoceanography PAR parameter optimization parasite particle flux particles partnerships pCO2 PDO peat pelagic perturbation PETM pH phenology phosphate phosphorus photosynthesis physical processes physiology phytoplankton PIC piezophilic piezotolerant plankton POC polar polar regions policy pollutants precipitation predation predator-prey predators prediction pressure primary productivity Prochlorococcus productivity prokaryotes proteins pteropods pycnocline python radioisotopes redox remineralization remote sensing repeat hydrography residence time resource management respiration resuspension rivers rocky shore Rossby waves Ross Sea ROV salinity salt marsh satellite scale seafloor seagrass sea ice sea level rise seasonal seasonal effects seasonality seasonal patterns seasonal trends sea spray sea surface seawater collection seaweed secchi sediments sensor sensors sequestration shelf ocean shelf system shells ship-based obs ship-based observations shorelines siderophore silica silicate silicon cycle sink sinking sinking particles size SOCCOM soil carbon solubility pump southern ocean south pacific spatial covariations speciation spring mixing SST state estimation stoichiometry stratification subduction submesoscale subpolar subtropical sulfate surf surface surface ocean surface water surface waters Synechococcus technology teleconnections temperate temperature temporal covariations thermocline thermodynamics thermohaline thorium tidal time time-series time of emergence titration top predators total alkalinity trace elements trace metals trait-based transfer efficiency transient features trawling Tris trophic interactions trophic transfer tropical turbulence twilight zone upper ocean upper water column upwelling US CLIVAR validation velocity gradient ventilation vertical flux vertical migration vertical transport viruses warming water clarity water column water mass water quality waves weathering western boundary currents wetlands winter mixing zooplankton

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