A5060347241- Marine and coastal ecosystems
- Oceanographic and Atmospheric Processes
- Marine Biology and Ecology Research
- Marine and fisheries research
- Ocean Acidification Effects and Responses
- Arctic and Antarctic ice dynamics
- Atmospheric and Environmental Gas Dynamics
- Methane Hydrates and Related Phenomena
- Marine Bivalve and Aquaculture Studies
- Climate variability and models
- Isotope Analysis in Ecology
- Coastal wetland ecosystem dynamics
- Soil and Water Nutrient Dynamics
- Hydrocarbon exploration and reservoir analysis
- Tropical and Extratropical Cyclones Research
- Geology and Paleoclimatology Research
- Fish Ecology and Management Studies
- Coastal and Marine Management
- Geological formations and processes
- Coastal and Marine Dynamics
- Marine and environmental studies
- Hydrology and Watershed Management Studies
- Aquatic and Environmental Studies
- Mycobacterium research and diagnosis
- Ichthyology and Marine Biology
William & Mary
2015-2024
Virginia Aquarium & Marine Science Center
2019
Virginia Institute of Marine Science
2008-2014
Old Dominion University
2001-2007
GEOMAR Technologie GmbH - GTG
1996
Massachusetts Institute of Technology
1993
Woods Hole Oceanographic Institution
1993
Application of biogeochemical models to the study marine ecosystems is pervasive, yet objective quantification these models' performance rare. Here, 12 lower trophic level varying complexity are objectively assessed in two distinct regions (equatorial Pacific and Arabian Sea). Each model was run within an identical one‐dimensional physical framework. A consistent variational adjoint implementation assimilating chlorophyll‐a, nitrate, export, primary productivity applied same metrics were...
Abstract Carbon cycling in the coastal zone affects global carbon budgets and is critical for understanding urgent issues of hypoxia, acidification, tidal wetland loss. However, there are no regional spanning three main ecosystems waters: wetlands, estuaries, shelf waters. Here we construct such a budget eastern North America using historical data, empirical models, remote sensing algorithms, process‐based models. Considering net fluxes total at domain boundaries, 59 ± 12% (± 2 standard...
The performance of 36 models (22 ocean color and 14 biogeochemical circulation (BOGCMs)) that estimate depth‐integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ C data at the Bermuda Atlantic Time series Study (BATS) Hawaii Ocean (HOT) over nearly two decades. Specifically, skill based on models' ability observed mean, variability, trends NPP. At both sites, more than 90% underestimated mean NPP, with average bias BOGCMs being twice models....
Abstract. Nearly half of the earth's photosynthetically fixed carbon derives from oceans. To determine global and region specific rates, we rely on models that estimate marine net primary productivity (NPP) thus it is essential these are evaluated to their accuracy. Here assessed skill 21 ocean color by comparing estimates depth-integrated NPP 1156 in situ 14C measurements encompassing ten regions including Sargasso Sea, pelagic North Atlantic, coastal Northeast Black Mediterranean Arabian...
Ocean ecosystems are subject to a multitude of stressors including changes in ocean physics and biogeochemistry, direct anthropogenic influences. Implementation protective adaptive measures for requires combination observations with analysis prediction tools. These can guide assessments the current state, elucidate ongoing trends shifts, anticipate impacts climate change management policies. Analysis tools defined here as circulation models that coupled biogeochemical or ecological models....
Abstract We investigated 32 net primary productivity (NPP) models by assessing skills to reproduce integrated NPP in the Arctic Ocean. The were provided with two sources each of surface chlorophyll‐ a concentration (chlorophyll), photosynthetically available radiation (PAR), sea temperature (SST), and mixed‐layer depth (MLD). most sensitive uncertainties chlorophyll, generally performing better situ chlorophyll than satellite‐derived values. They much less PAR, SST, MLD, possibly due...
Abstract The magnitude, spatiotemporal patterns, and controls of carbon flux from land to the ocean remain uncertain. Here we applied a process‐based model with explicit representation processes in streams rivers examine how changes climate, conversion, management practices, atmospheric CO 2 , nitrogen deposition affected fluxes eastern North America Atlantic Ocean, specifically Gulf Maine (GOM), Middle Bight (MAB), South (SAB). Our simulation results indicate that mean annual (±1 standard...
[1] Underway and in situ observations of surface ocean pCO2, combined with satellite data, were used to develop pCO2 regional algorithms analyze the seasonal interannual variability sea-air CO2 flux for five physically biologically distinct regions eastern North American continental shelf: South Atlantic Bight (SAB), Mid-Atlantic (MAB), Gulf Maine (GoM), Nantucket Shoals Georges Bank (NS+GB), Scotian Shelf (SS). Temperature dissolved inorganic carbon are most influential factors driving...
Abstract The Chesapeake Bay plays an important role in transforming riverine nutrients before they are exported to the adjacent continental shelf. Although mean nitrogen budget of has been previously estimated from observations, uncertainties associated with interannually varying hydrological conditions remain. In this study, a land‐estuarine‐ocean biogeochemical modeling system is developed quantify inputs, within‐estuary transformation processes and ultimate export coastal ocean. Model...
Abstract. The Chesapeake Bay region is projected to experience changes in temperature, sea level, and precipitation as a result of climate change. This research uses an estuarine-watershed hydrodynamic–biogeochemical modeling system along with mid-21st-century freshwater flow, level rise explore the impact change may have on future dissolved-oxygen (DO) concentrations potential success nutrient reductions attaining mandated estuarine water quality improvements. Results indicate that warming...
Abstract Global carbon dioxide (CO 2 ) evasion from inland waters (rivers, lakes, and reservoirs) (C) export land to oceans constitute critical terms in the global C budget. However, magnitudes, spatiotemporal patterns, underlying mechanisms of these fluxes are poorly constrained. Here, we used a coupled terrestrial–aquatic model assess how multiple changes climate, use, atmospheric CO concentration, nitrogen (N) deposition, N fertilizer manure applications have affected riverine along...
Abstract. As three-dimensional (3-D) aquatic ecosystem models are used more frequently for operational water quality forecasts and ecological management decisions, it is important to understand the relative strengths limitations of existing 3-D varying spatial resolution biogeochemical complexity. To this end, 2-year simulations Chesapeake Bay from eight hydrodynamic-oxygen have been statistically compared each other historical monitoring data. Results show that although difficulty resolving...
Abstract We used a process‐based land model, Dynamic Land Ecosystem Model 2.0, to examine how climatic and anthropogenic changes affected riverine fluxes of ammonium (NH 4 + ), nitrate (NO 3 − dissolved organic nitrogen (DON), particulate (PON) from eastern North America, especially the drainage areas Gulf Maine (GOM), Mid‐Atlantic Bight (MAB), South Atlantic (SAB) during 1901–2008. simulations indicated that annual NH , NO DON, PON study area 1980–2008 were 0.019 ± 0.003 (mean 1 standard...
Lower trophic level marine ecosystem models are highly dependent on the parameter values given to key rate processes, however many of these either unknown or difficult measure. One solution this problem is apply data assimilation techniques that optimize values, in cases situ unavailable temporal and spatial scales interest. Although multiple types satellite-derived now available with high resolution, relative advantages assimilating different satellite not well known. Here issues examined...