Scott C. Doney

University of Virginia | UVa · Department of Environmental Sciences

To achieve net zero carbon emissions by mid-century, the United States may need to rely on carbon dioxide removal (CDR) to offset emissions from difficult-to-decarbonize sectors and/or shortfalls in near-term mitigation efforts. CDR can be delivered using many approaches with different requirements for land, water, geologic carbon storage capacity,...

This study characterized ocean biological carbon pump metrics in the second iteration of the REgional Carbon Cycle Assessment and Processes (RECCAP2) project. The analysis here focused on comparisons of global and biome‐scale regional patterns in particulate organic carbon (POC) production and sinking flux from the RECCAP2 ocean biogeochemical mode...

Scenarios to stabilize global climate and meet international climate agreements require rapid reductions in human carbon dioxide (CO 2 ) emissions, often augmented by substantial carbon dioxide removal (CDR) from the atmosphere. While some ocean-based removal techniques show potential promise as part of a broader CDR and decarbonization portfolio,...

To inform water quality monitoring techniques and modeling at coastal research sites, this study investigated seasonality and trends in coastal lagoons on the eastern shore of Virginia, USA. Seasonality was quantified with harmonic analysis of low-frequency time-series, approximately 30 years of quarterly sampled data at thirteen mainland, lagoon,...

Keeping global surface temperatures below international climate targets will require substantial measures to control atmospheric CO2 and CH4 concentrations. Recent studies have focused on interventions to decrease CH4 through enhanced atmospheric oxidation. Here for the first time using a set of models, we evaluate the effect of adding iron aerosol...

This study characterized ocean biological carbon pump metrics in the second iteration of the REgional Carbon Cycle Assessment and Processes (RECCAP2) project, a coordinated, international effort to constrain contemporary ocean carbon air-sea fluxes and interior carbon storage trends using a combination of observation-based estimates, inverse models...

Interannual variability (IAV) in the atmospheric CO2 growth rate is caused by variation in the balance between uptake by land and ocean and accumulation of anthropogenic emissions in the atmosphere. While variations in terrestrial fluxes are thought to drive most of the observed atmospheric CO2 IAV, the ability to characterize ocean impacts has bee...

The coastal ocean contributes to regulating atmospheric greenhouse gas concentrations by taking up carbon dioxide (CO2) and releasing nitrous oxide (N2O) and methane (CH4). In this second phase of the Regional Carbon Cycle Assessment and Processes (RECCAP2), we quantify global coastal ocean fluxes of CO2, N2O and CH4 using an ensemble of global gap...

Recent marine heatwaves in the Gulf of Alaska have had devastating impacts on species from various trophic levels. Due to climate change, total heat exposure in the upper ocean has become longer, more intense, more frequent, and more likely to happen at the same time as other environmental extremes. The combination of multiple environmental extreme...

We assess the Southern Ocean CO2 uptake (1985–2018) using data sets gathered in the REgional Carbon Cycle Assessment and Processes Project Phase 2. The Southern Ocean acted as a sink for CO2 with close agreement between simulation results from global ocean biogeochemistry models (GOBMs, 0.75 ± 0.28 PgC yr⁻¹) and pCO2‐observation‐based products (0.7...

This contribution to the RECCAP2 (REgional Carbon Cycle Assessment and Processes) assessment analyzes the processes that determine the global ocean carbon sink, and its trends and variability over the period 1985–2018, using a combination of models and observation‐based products. The mean sea‐air CO2 flux from 1985 to 2018 is −1.6 ± 0.2 PgC yr⁻¹ ba...

Coastal landscapes are naturally shifting mosaics of distinct ecosystems that are rapidly migrating with sea-level rise. Previous work illustrates that transitions among individual ecosystems have disproportionate impacts on the global carbon cycle, but this cannot address nonlinear interactions between multiple ecosystems that potentially cascade...

Recent marine heatwaves in the Gulf of Alaska have had devastating and lasting impacts on species from various trophic levels. As a result of climate change, total heat exposure in the upper ocean has become longer, more intense, more frequent, and more likely to happen at the same time as other environmental extremes. The combination of multiple e...

Net-zero greenhouse gas emission targets are central to current international efforts to stabilize global climate, and many of these plans rely on carbon dioxide removal (CDR) to meet mid-century goals. CDR can be performed via nature-based approaches, such as afforestation, or engineered approaches, such as direct air capture. Both will have large...

Marine diazotrophs convert dinitrogen (N2) gas into bioavailable nitrogen (N), supporting life in the global ocean. In 2012, the first version of the global oceanic diazotroph database (version 1) was published. Here, we present an updated version of the database (version 2), significantly increasing the number of in situ diazotrophic measurements...

Atmospheric methane is both a potent greenhouse gas and photochemically active, with approximately equal anthropogenic and natural sources. The addition of chlorine to the atmosphere has been proposed to mitigate global warming through methane reduction by increasing its chemical loss. However, the potential environmental impacts of such climate mi...

Understanding and attributing changes to water quality is essential to the study and management of coastal ecosystems and the ecological functions they sustain (e.g., primary productivity, predation, and submerged aquatic vegetation growth). However, describing patterns of water clarity—a key aspect of water quality—over meaningful scales in space...

Processes driving changes in sea-ice seasonality and sea-ice thickness were explored for a ‘warm-shelf’ region along the West Antarctic Peninsula using vertically coupled sea-ice-ocean thermodynamic simulations, with and without assimilated satellite sea-ice observations and moored ocean temperature observations. Simulations with assimilated sea-ic...

We assess the Southern Ocean CO2 uptake (1985-2018) using data sets gathered in the REgional Carbon Cycle Assessment and Processes Project phase 2 (RECCAP2). The Southern Ocean acted as a sink for CO2 with close agreement between simulation results from global ocean biogeochemistry models (GOBMs, 0.75±0.28 PgCyr-1) and pCO2-observation-based produc...

Nitrous oxide (N2O) is a potent greenhouse gas and ozone depleting substance, with the ocean accounting for about one third of global emissions. In marine environments, a significant amount of N2O is produced by biological processes in Oxygen Deficient Zones (ODZs). While recent technological advances are making surface N2O concentration more avail...

Atmospheric carbon dioxide (CO2) accounts for the largest radiative forcing among anthropogenic greenhouse gases. There is, therefore, a pressing need to understand the rate at which CO2 accumulates in the atmosphere, including the interannual variations (IAVs) in this rate. IAV in the CO2 growth rate is a small signal relative to the long-term tre...

The noble gas signature of incoming Pacific Bottom Water (PBW), when compared to North Atlantic Deep Water, indicates the addition of 450 ± 70 GT a⁻¹ glacial melt water to form AABW and subsequently PBW. The downstream evolution of this signature between the southern (20°S to equator) and northern (25°–45°N) bottom waters indicates a decrease in se...

The coastal ocean contributes to regulating atmospheric greenhouse gas concentrations by taking up carbon dioxide (CO2) and releasing nitrous oxide (N2O) and methane (CH4). Major advances have improved our understanding of the coastal air-sea exchanges of these three gasses since the first phase of the Regional Carbon Cycle Assessment and Processes...

The straining regions of the ocean in between mesoscale eddies contain large vertical velocities that may be important in regulating phytoplankton accumulation rates. We analyze time series of variables measured by ocean Bio‐Argo floats (mixed layer depths [MLDs], chlorophyll, and carbon concentrations) in conjunction with variables derived from sa...

Carbon dioxide removal (CDR) is a critical tool in all plans to limit warming to below 1.5 °C, but only a few CDR pathways have been incorporated into integrated assessment models that international climate policy deliberations rely on. A more diverse set of CDR approaches could have important benefits and costs for energy–water–land systems. Here...

Marine heterotrophic Bacteria (or referred to as bacteria) play an important role in the ocean carbon cycle by utilizing, respiring, and remineralizing organic matter exported from the surface to deep ocean. Here, we investigate the responses of bacteria to climate change using a three-dimensional coupled ocean biogeochemical model with explicit ba...

Variations in atmosphere total column‐mean CO2 (XCO2) collected by the National Aeronautics and Space Administration's Orbiting Carbon Observatory‐2 satellite can be used to constrain surface carbon fluxes if the influence of atmospheric transport and observation errors on the data is known and accounted for. Due to sparse validation data, the port...

Phytoplankton form the base of marine food webs and play an important role in carbon cycling, making it important to quantify rates of biomass accumulation and loss. As phytoplankton drift with ocean currents, rates should be evaluated in a Lagrangian as opposed to an Eulerian framework. In this study, we quantify the Lagrangian (from Bio-Argo floa...

Atmospheric carbon dioxide (CO2) accounts for the largest radiative forcing among anthropogenic greenhouse gases. There is, therefore, a pressing need to understand the rate at which CO2 accumulates in the atmosphere, including the interannual variations (IAV) in this rate. IAV in the CO2 growth rate is a small signal relative to the long-term tren...

A key challenge for current‐generation Earth system models (ESMs) is the simulation of the penetration of sinking particulate organic carbon (POC) into the ocean interior, which has implications for projections of future oceanic carbon sequestration in a warming climate. This paper presents a new, cost‐efficient, mechanistic 1D model that prognosti...

Ocean biogeochemical models describe the ocean’s circulation, physical properties, biogeochemical properties and their transformations using coupled differential equations. Numerically approximating these equations enables simulation of the dynamic evolution of the ocean state in realistic global or regional spatial domains, across time spans from...

The influence of global change on Southern Ocean productivity will have major ramifications for the future management of polar living resources. A prior laboratory study investigated the response of a batch-cultured subantarctic diatom to global ocean change (concurrent increases in temperature/CO2/irradiance/iron; decreased macronutrients), reveal...

Phytoplankton form the base of marine food webs and play an important role in carbon cycling, making it important to quantify rates of biomass accumulation and loss. Since phytoplankton drift with ocean currents, rates should be evaluated in a Lagrangian as opposed to Eulerian framework. In this study, we quantify the Lagrangian (from Bio-Argo floa...

One-quarter of photosynthesis-derived carbon on Earth rapidly cycles through a set of short-lived seawater metabolites that are generated from the activities of marine phytoplankton, bacteria, grazers and viruses. Here we discuss the sources of microbial metabolites in the surface ocean, their roles in ecology and biogeochemistry, and approaches th...

Heterotrophic marine bacteria utilize organic carbon for growth and biomass synthesis. Thus, their physiological variability is key to the balance between the production and consumption of organic matter and ultimately particle export in the ocean. Here we investigate a potential link between bacterial traits and ecosystem functions in the rapidly...

The Marine Biogeochemistry Library (MARBL) is a prognostic ocean biogeochemistry model that simulates marine ecosystem dynamics and the coupled cycles of carbon, nitrogen, phosphorus, iron, silicon, and oxygen. MARBL is a component of the Community Earth System Model (CESM); it supports flexible ecosystem configuration of multiple phytoplankton and...

The development of the shared socioeconomic pathways (SSPs) and associated integrated assessment modeling exercises did not include direct air capture with carbon storage (DACCS) in their scenarios. Recent progress in DACCS commercialization suggests it could be a viable means of removing CO2 from the atmosphere with far lower land intensity than b...

Ocean-based carbon dioxide (CO2) removal (CDR) strategies are an important part of the portfolio of approaches needed to achieve negative greenhouse gas emissions. Many ocean-based CDR strategies rely on injecting CO2 or organic carbon (that will eventually become CO2) into the ocean interior, or enhancing the ocean’s biological pump. These approac...

Although a wide body of scholarly research recognizes multiple kinds of values for water, water security assessments typically employ just some of them. In the present article, we integrate value scenarios into a planetary water security model to incorporate multiple water-related social values and illustrate trade-offs among them. Specifically, we...

Uptake of anthropogenic carbon dioxide from the atmosphere by the surface ocean is leading to global ocean acidification, but regional variations in ocean circulation and mixing can dampen or accelerate apparent acidification rates. Here we use a regional ocean model simulation for the years 1980 to 2013 and observational data to investigate how oc...

Ocean phytoplankton play a critical role in the global carbon cycle, contributing ∼50% of global photosynthesis. As planktonic organisms, phytoplankton encounter significant environmental variability as they are advected throughout the ocean. How this variability impacts phytoplankton growth rates and population dynamics remains unclear. Here, we s...

The air‐sea exchange of oxygen (O2) is driven by changes in solubility, biological activity, and circulation. The total air‐sea exchange of O2 has been shown to be closely related to the air‐sea exchange of heat on seasonal timescales, with the ratio of the seasonal flux of O2 to heat varying with latitude, being higher in the extratropics and lowe...

The West Antarctic Peninsula (WAP) is a rapidly warming region, with substantial ecological and biogeochemical responses to the observed change and variability for the past decades, revealed by multi-decadal observations from the Palmer Antarctica Long-Term Ecological Research (LTER) program. The wealth of these long-term observations provides an i...

We examine the effects of negative emission technologies availability on fossil fuel-based electricity generating assets under deep decarbonization trajectories. Our study focuses on potential premature retirements (stranding) and committed emissions of existing power plants globally and the effects of deploying direct air carbon capture and biomas...

China’s pledge to reach carbon neutrality before 2060 is an ambitious goal and could provide the world with much-needed leadership on how to limit warming to +1.5°C warming above preindustrial levels by the end of the century. But the pathways that would achieve net zero by 2060 are still unclear, including the role of negative emissions technologi...

The ocean coastal‐shelf‐slope ecosystem west of the Antarctic Peninsula (WAP) is a biologically productive region that could potentially act as a large sink of atmospheric carbon dioxide. The duration of the sea‐ice season in the WAP shows large interannual variability. However, quantifying the mechanisms by which sea ice impacts biological product...

We examine the effects of negative emission technologies availability on fossil fuel-based electricity generating assets under deep decarbonization trajectories. Our study focuses on potential premature retirements (stranding) and committed emissions of existing power plants globally and the effects of deploying direct air carbon capture and biomas...

High-resolution ocean biophysical models are now routinely being conducted at basin and global-scale, opening opportunities to deepen our understanding of the mechanistic coupling of physical and biological processes at the mesoscale. Prior to using these models to test scientific questions, we need to assess their skill. While progress has been ma...

For the first time the annual carbon budget on the West Antarctic Peninsula shelf was studied with continuously measured CO2 system parameters (pH and pCO2) from a subsurface mooring. The temporal evolution of the mixed layer dissolved inorganic carbon (DIC) is investigated via a mass balance. The annual mixed layer DIC inventory change was 1.1 ± 0...

The ¹⁴C incubation method for net primary production (NPP) has limited spatial/temporal resolution, while satellite approaches cannot provide direct information at depth. With chlorophyll‐a and backscatter measurements from BGC‐Argo floats, we quantified year‐round NPP in the western North Atlantic Ocean using both the Carbon‐based Productivity Mod...

Global Earth system model simulations of ocean carbon export flux are commonly interpreted only at a fixed depth horizon of 100 m, despite the fact that the maximum annual mixed layer depth (MLDmax) is a more appropriate depth horizon to evaluate export‐driven carbon sequestration. We compare particulate organic carbon (POC) flux and export efficie...