A5062043920- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Atmospheric and Environmental Gas Dynamics
- Marine and coastal ecosystems
- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Cardiovascular Effects of Exercise
- Climate change and permafrost
- Oceanographic and Atmospheric Processes
- Winter Sports Injuries and Performance
- Ocean Acidification Effects and Responses
- Climate variability and models
- Coastal wetland ecosystem dynamics
- Atmospheric chemistry and aerosols
- Extracellular vesicles in disease
- Landslides and related hazards
- Atmospheric Ozone and Climate
- Geological Studies and Exploration
- Marine Biology and Ecology Research
- Polar Research and Ecology
- Earthquake Detection and Analysis
- Carbon Dioxide Capture Technologies
- Coral and Marine Ecosystems Studies
- earthquake and tectonic studies
- Microbial Community Ecology and Physiology
Moss Landing Marine Laboratories
2019-2025
Jet Propulsion Laboratory
2018-2025
San Jose State University
2019-2025
Max Planck Institute for Biogeochemistry
2023
National and Kapodistrian University of Athens
2023
California Institute of Technology
2020-2021
Center for Dynamic Research on High Latitude Marine Ecosystems
2019
University of California, Los Angeles
2018
University of Oregon
2013-2017
Abstract. Freshwater discharge from glaciers is increasing across the Arctic in response to anthropogenic climate change, which raises questions about potential downstream effects marine environment. Whilst a combination of long-term monitoring programmes and intensive field campaigns have improved our knowledge glacier–ocean interactions recent years, especially with respect fjord/ocean circulation, there are extensive gaps concerning how affect biogeochemistry productivity. Following two...
Abstract. Accurate accounting of emissions and removals CO2 is critical for the planning verification emission reduction targets in support Paris Agreement. Here, we present a pilot dataset country-specific net carbon exchange (NCE; fossil plus terrestrial ecosystem fluxes) stock changes aimed at informing countries' budgets. These estimates are based on “top-down” NCE outputs from v10 Orbiting Carbon Observatory (OCO-2) modeling intercomparison project (MIP), wherein an ensemble inverse...
Abstract This contribution to the RECCAP2 (REgional Carbon Cycle Assessment and Processes) assessment analyzes processes that determine global ocean carbon sink, its trends variability over period 1985–2018, using a combination of models observation‐based products. The mean sea‐air CO 2 flux from 1985 2018 is −1.6 ± 0.2 PgC yr −1 based on an ensemble reconstructions history sea surface pCO (pCO products). Models indicate dominant component this net oceanic uptake anthropogenic , which...
Runoff from the Greenland Ice Sheet (GrIS) is thought to enhance marine productivity by adding bioessential iron and silicic acid coastal waters. However, experimental data suggest nitrate main summertime growth-limiting resource in regions affected meltwater around Greenland. While contains low concentrations, subglacial discharge plumes marine-terminating glaciers entrain large quantities of deep seawater. Here, we characterize fluxes that arise entrainment seawater within these using a...
Abstract Fjord-scale circulation forced by rising turbulent plumes of subglacial meltwater has been identified as one possible mechanism oceanic heat transfer to marine-terminating outlet glaciers. This study uses buoyant plume theory and a nonhydrostatic, three-dimensional ocean–ice model typical glacier fjord in west Greenland investigate the sensitivity dynamics fjord-scale discharge rates, ambient stratification, diffusivity, conduit geometry. The terminal level depends on cumulative...
Abstract Meltwater from the Greenland Ice Sheet often drains subglacially into fjords, driving upwelling plumes at glacier termini. Ocean models and observations of submarine termini suggest that enhance melt undercutting, leading to calving potential destabilization. Here we systematically evaluate how simulated plume structure during summer months depends on realistic ranges subglacial discharge, depth, ocean stratification 12 fjords. Our results show grounding line depth is a strong...
Abstract Quantifying variability in the ocean carbon sink remains problematic due to sparse observations and spatiotemporal surface p CO 2 . To address this challenge, we have updated improved ECCO‐Darwin, a global biogeochemistry model that assimilates both physical biogeochemical observations. The consists of an adjoint‐based circulation estimate from Estimating Circulation Climate Ocean (ECCO) consortium ecosystem developed by Massachusetts Institute Technology Darwin Project. In addition...
Dispersal provides a key mechanism for geographical range shifts in response to changing environmental conditions. For mangroves, which are highly susceptible climate change, the spatial scale of dispersal remains largely unknown. Here we use high-resolution, eddy- and tide-resolving numerical ocean model simulate mangrove propagule across global generate connectivity matrices between habitats using floating periods. We find high rates along-coast transport transoceanic Atlantic, Pacific,...
Abstract. Here we present a global and regionally resolved terrestrial net biosphere exchange (NBE) dataset with corresponding uncertainties between 2010–2018: Carbon Monitoring System Flux Net Biosphere Exchange 2020 (CMS-Flux NBE 2020). It is estimated using the NASA (CMS-Flux) top-down flux inversion system that assimilates column CO2 observations from Greenhouse Gases Observing Satellite (GOSAT) NASA's Observatory 2 (OCO-2). The regional monthly fluxes are readily accessible as tabular...
Abstract The classic model of fjord renewal is complicated by tidewater glacier fjords, where submarine melt and subglacial discharge provide substantial buoyancy forcing at depth. Here we use a suite idealized, high‐resolution numerical ocean simulations to investigate how circulation driven plumes, tides, wind stress depends on width, grounding line depth, sill height. We find that the depth compared primary control plume‐driven basin waters. In wide fjords plume exhibits strong lateral...
Abstract At tidewater glaciers, plume dynamics affect submarine melting, fjord circulation, and the mixing of meltwater. Models often rely on buoyant theory to parameterize plumes melting; however, these parameterizations are largely untested due a dearth near‐glacier measurements. Here we present high‐resolution ocean survey by ship remotely operated boat near terminus Kangerlussuup Sermia in west Greenland. These novel observations reveal 3‐D structure transport near‐surface plume,...
The inventory and variability of oceanic dissolved inorganic carbon (DIC) is driven by the interplay physical, chemical, biological processes. Quantifying spatiotemporal these drivers crucial for a mechanistic understanding ocean sink its future trajectory. Here, we use Estimating Circulation Climate Ocean-Darwin biogeochemistry state estimate to generate global-ocean, data-constrained DIC budget investigate how spatial seasonal-to-interannual in three-dimensional circulation, air-sea CO2...
Abstract The degree to which the distribution of mangrove forests will be impacted by climate change depends on dispersal and establishment sea-faring propagules, drive forest rejuvenation, gene flow range expansion. Climate affects sea surface density via changes in temperature salinity. However, these have not been mapped it remains unclear how factors may impact propagule dispersal. Here, we provide evidence for strong warming coastal waters elevated geographic variability ocean under...
The ocean plays a central role in modulating the Earth's carbon cycle. Monitoring how cycle is changing fundamental to managing climate change. Satellite remote sensing currently our best tool for viewing surface globally and systematically, at high spatial temporal resolutions, past few decades have seen an exponential growth studies utilising satellite data research. Satellite-based observations must be combined with in-situ models, obtain comprehensive view of pools fluxes. To help...
ABSTRACT Neighboring tidewater glaciers often exhibit asynchronous dynamic behavior, despite relatively uniform regional atmospheric and oceanic forcings. This variability may be controlled by a combination of local factors, including glacier fjord geometry, heat content circulation, surface melt. In order to characterize understand contrasts in adjacent dynamics, we made coincident ice-ocean-atmosphere observations at high temporal resolution (minutes weeks) within 10 000 km 2 area near...
Marine phytoplankton growth at high latitudes is extensively limited by iron availability. Icebergs are a vector transporting the bioessential micronutrient into polar oceans. Therefore, increasing iceberg fluxes due to global warming have potential increase marine productivity and carbon export, creating negative climate feedback. However, magnitude of flux, subsequent fertilization effect resultant export not been quantified. Using analysis samples, we reveal that concentrations vary over...
Abstract Greenland's glacial fjords are a key bottleneck in the earth system, regulating exchange of heat, freshwater and nutrients between ice sheet ocean hosting societally important fisheries. We combine recent bathymetric, atmospheric, oceanographic data with buoyant plume model to show that summer subglacial discharge from 136 tidewater glaciers, amounting 0.02 Sv freshwater, drives 0.6–1.6 upwelling. Bathymetric analysis suggests this is sufficient renew most major within single...
Abstract Arctic warming alters land‐to‐sea fluxes of nutrients and organic matter, which impact air‐sea carbon exchange. Here we use an ocean‐biogeochemical model the southeastern Beaufort Sea (SBS) to investigate role Mackenzie River biogeochemical discharge in modulating CO 2 during 2000–2019. The contribution six constituents leads a net outgassing 0.13 TgC yr −1 , with decrease coastal SBS sink 0.23 0.4 due riverine dissolved inorganic carbon, respectively. Years high (low) promote more...
Abstract As a contribution to the Regional Carbon Cycle Assessment and Processes phase 2 (RECCAP2) project, we present synthesized estimates of Arctic Ocean sea‐air CO fluxes their uncertainties from surface ocean p ‐observation products, biogeochemical hindcast data assimilation models, atmospheric inversions. For period 1985–2018, was net sink 116 ± 4 TgC yr −1 in 92 30 91 21 The uptake peaks late summer early autumn, is low winter when sea ice inhibits fluxes. long‐term mean primarily...
The Paris Agreement calls for emissions reductions to limit climate change, but how will the carbon cycle change if it is successful? land and oceans currently absorb roughly half of anthropogenic emissions, this fraction decline in future. amount that can be released before mitigated depends on ocean terrestrial ecosystems absorb. Policy based model projections, observations theory suggest effects emerging today's increase tipping points may crossed. Warming temperatures, drought, a slowing...
Around the Greenlandic and Antarctic coastlines, sediment plumes associated with glaciers are significant sources of lithogenic material to ocean. These contain elevated concentrations a range trace metals, especially in particle bound phases, but it is not clear how these particles affect dissolved (<0.2 µm) metal distributions Here we show, using transects 8 glacier fjords, trends distribution iron, cobalt, nickel copper (dFe, dCo, dNi, dCu). Following rapid dFe loss close outflows,...
Abstract Latitudinal range limits for mangroves on high‐energy, wave‐dominated coasts are controlled by geomorphological features and estuarine dynamics. Mangroves reach a southern global limit along the South African coastline, but distribution is patchy, with stands occurring in only 16% of estuaries region. Yet, persistence forests planted >50 years ago beyond natural suggests that additional could support mangroves. Understanding regional drivers necessary to inform global‐scale...
Abstract Discharge of calved ice, runoff and mixing driven by subglacial discharge plumes likely have consequences for marine biogeochemistry in Disko Bay, which hosts the largest glacier northern hemisphere, Sermeq Kujalleq. Glacier retreat increasing may impact silica cycle because glaciers deliver elevated concentrations dissolved (dSi) compared to other macronutrients. However, annual flux dSi delivered ocean from Greenland Ice Sheet is poorly constrained difficulties distinguishing...