Task III Projects

The Cooperative Institute for Modeling the Earth System (CIMES) has announced awards totaling $570,000 to support eight innovative, cross-disciplinary projects aimed at modeling and understanding the Earth system, projects that align closely with the strategic goals of NOAA’s Geophysical Fluid Dynamics Laboratory (GFDL). The projects run from 2021 to 2022 and foster research, teaching, and mentorship in Earth system science.

The recently funded projects include:

Coastal Microscale Dynamics and their Parametrization

Land-Sea breezes are strong air circulations that dominate the wind patterns in coastal zones. They are fueled by the surface temperature differences between the adjacent water and land surfaces. Much remains to be learned about the physics of these circulations, and more importantly about how to represent them in weather and climate models. This is increasingly urgent given the hazards coastal zones are going to face with a changing climate and the potential drastic increase in offshore wind farms. Led by Elie Bou-Zeid, professor of civil and environmental engineering, this project will bridge the gap in physical understanding, apply it to improve forecasting in coastal zones at weather to climate scales, with positive impact for coastal resilience and sustainability.

A Sea-State Dependent Sea Spray Source Function

Luc Deike, assistant professor of mechanical and aerospace engineering and the High Meadows Environmental Institute, will lead research aimed at developing accurate models of sea spray generation function that can be implemented in ocean, atmosphere and Earth system models, with potential impacts on chemical cycles and aerosol production. Deike and collaborators Brandon Reichl, a GFDL research oceanographer, and AOS Faculty Member Steve Griffies, a GFDL physical scientist, are developing and testing a theoretical framework that explicitly accounts for the role of sea spray aerosol generation by wave breaking and bubble bursting, resolving the very large range of scales involved in the process by a sequence of models, from the atmospheric and wave scales (scales of tens to hundreds of km), to wave breaking, (scales of tens of meters), to air bubble entrainment and bubble bursting at the free surface (scales of microns to mm). Once the sea spray generation function is available at global scales through global wave simulations, we expect to collaborate closely with Paul Ginoux, Larry Horowitz and Fabien Paulot at GFDL.

Dynamic Elemental Stoichiometry in COBALT

Single-celled organisms called phytoplankton absorb sunlight, carbon dioxide, and other nutrients in the ocean's surface and eventually transfer them deep below the surface. This carbon pump strongly influences our atmosphere, climate, and the ocean environment by altering the distribution of carbon, oxygen, and nutrients throughout oceans. In this project, a team of interdisciplinary researchers led by George Hagstrom, associate research scholar in ecology and evolutionary biology, aims to better understand the controls on the carbon pump by modelling how the ratios of carbon:nitrogen:phosphorus in phytoplankton vary with environmental and ecological conditions. Usually modelled as constant, recent laboratory and field data suggests that phytoplankton vary their nutrient ratios in response to the environment, becoming extremely efficient at using phosphorus when nutrients are scarce. By capturing dynamic stoichiometry in GFDL's global ocean models, the researchers, including GFDL Research Oceanographers Charles Stock and Jessica Luo and Simon Levin, the James S. McDonnell Distinguished University Professor in Ecology and Evolutionary Biology, will improve their understanding of carbon export in the current ocean and also better predict how marine ecosystems respond to human-caused environmental changes such as pollution or climate change, enabling society to better plan for the future.

Validating, Improving, and Assessing Marine Nitrification under Climate Change in GFDL’s Earth
System Model 4 (ESM4)

Nitrification, the microbially mediated oxidation of ammonium to nitrate, controls the availability of different forms of nitrogen to support primary production. It also results in the formation of nitrous oxide, a potent greenhouse gas. In this project, Bess Ward, the William J. Sinclair Professor of Geosciences and the High Meadows Environmental Institute, and a team of researchers, including Weiyi Tang, a postdoctoral research associate in Geosciences, will assess the sensitivity of marine nitrification to climate/anthropogenic change including warming, ocean acidification and increasing N deposition. The researchers have developed a database of nitrification rate measurements, and have parameterized the relationship among reaction rates and environmental variables. New parameterizations and machine learning methods will be used to improve the representation of nitrification in global models in order to improve models and predictions of the response of marine productivity to ecosystem stress and climate
change.

A Statistical Perspective of the Tropical Circulation – Theory and Empirical Support

Tropical deep convection is observed to be organized on a range of spatial and temporal scales. In this project, Stephan Fueglistaler, associate professor of geosciences, and AOS Graduate Student Yi Zhang explore alternatives to the traditional geographic perspective to describe and understand the organization of tropical deep convection. Published results from this project include a theoretical argument why tropical rainfall distribution is expected to become (even) less evenly distributed under global warming (Zhang and Fueglistaler, GRL, 2019), and empirical proof in observations and model simulations (Zhang and Fueglistaler, GRL, 2020) that the subcloud moist static energy in regions of tropical deep convection is equal over land and ocean in all climates (ranging from past cold glacial to future warm climates).  These results have important implications for heat stress at low latitudes (Zhang et al. 2021).

References:

  1. Zhang, Y., S. Fueglistaler, Mechanism for Increasing Tropical Rainfall Unevenness with Global Warming, Geophys. Res. Letts., 46, 14,836–14,843, doi.org/10.1029/ 2019GL086058, 2019.
  2. Zhang, Y., S. Fueglistaler, How tropical convection couples high moist static energy over land and ocean, Geophys. Res. Letts., 47 (2), e2019GL086387, doi:10.1029/2019GL086387, 2020.
  3. Zhang, Y., Held, I. & Fueglistaler, S. Projections of tropical heat stress constrained by atmospheric dynamics. Nat. Geosci. 14, 133–137 (2021). https://doi.org/10.1038/s41561-021-00695-3.

Evaluating the Biological Carbon Pump in a Water Mass Framework

The ocean’s “biological pump” is a mechanism by which organic matter, which grows in the sunlit surface waters, is transported to the deep ocean. By moving carbon away from the surface, the process plays a crucial role in mediating levels of atmospheric pCO2 on timescales from decades to millennia. This project is about putting a novel spin on our framing of the biological pump, to assist in quantifying its magnitude and understanding its dynamics. In this project, Graeme MacGilchrist, an AOS postdoctoral research associate, and collaborators AOS Faculty Member Steve Griffies, a GFDL physical scientist, John Dunne, a GFDL research oceanographer, GFDL Physical Scientist John Krasting, and Jorge Sarmiento, the George J. Magee Professor of Geoscience and Geological Engineering, Emeritus, will analyze GFDL’s Earth System Models (ESMs) in a framework that considers the ocean as a stack of moveable layers through which we can accurately quantify the movement of organic matter. The novel approach is hypothesized to help constrain our understanding of this critical process and improve its representation in ESMs, ultimately improving centennial-timescale climate projections.

Extreme Rainfall and Flooding the Lower Mississippi River Basin

One of the most consequential issues concerning climate change impacts on flooding in the US is whether extreme floods in the Lower Mississippi River are increasing in frequency.  In this project, James Smith, the William and Edna Macaleer Professor of Engineering and Applied Science, and Yibing Su, a graduate student in civil and environmental engineering, will address the following questions: How is rainfall organized in space and time for extreme flood events in the Lower Mississippi River? Can state-of-the-art Earth System Models accurately represent rainfall variability at time and space scales associated with major Lower Mississippi River flood episodes?  What are the principal climate drivers of extreme rainfall in the Lower Mississippi River? and Are extreme floods in the Lower Mississippi River increasing in frequency? A core objective of this project is assessing and enhancing the capabilities of Earth System Models developed by GFDL to simulate extreme convective rainfall. 

Urbanization and Compound Heat Waves

A Compound Heat wave is defined as a period of multiple extreme heat days separated by short breaks of cooler days. Prolonged exposure to extreme heat can worsen existing health conditions such as cardiovascular and respiratory diseases, and increase the mortality rate. Also, extreme heat can intensify droughts, cause forest fires and lead to a surge in energy demand for cooling. With global warming, the frequency and intensity of compound heat waves is expected to increase1, exacerbating these pre-existing risks. In addition to global warming, urbanization can cause local warming often referred to as the ‘Urban Heat island effect’ where urban areas tend to be warmer than their surrounding rural areas. In this project, a team of researchers in Princeton’s Department of Geosciences, High Meadows Environmental Institute and School of International and Public Affairs, NOAA/GFDL, Columbia University, and Boston University, will assess the effect of urban versus rural characteristics on the intensity and frequency of compound heatwaves, and how the projected increase in compound heat waves can pose different risks for urban vs. rural areas using global climate model simulations of GFDL LM4 with the urban module enabled2.

Team Members:
Sirisha Kalidindi, Princeton Department of Geosciences; Gabriel Vecchi, Princeton Department of Geosciences and High Meadows Environmental Institute; Michael Oppenheimer, Princeton Department of Geosciences, High Meadows Environmental Institute and School of International and Public Affairs; Elena Shevliakova, NOAA/GFDL; Sergey Malyshev, NOAA/GFDL; Jane Baldwin, Columbia University; Dan Li, Boston University

References:

1.    Baldwin, J.W., Dessy, J.B., Vecchi, G.A., Oppenheimer, M., 2019. Temporally compound heat wave events and global warming: an emerging hazard. Earth’s Future 7, 411–427.
2.    Li, D., S. Malyshev, and E. Shevliakova. “Exploring Historical and Future Urban Climate in the Earth System Modeling Framework: 1. Model Development and Evaluation.” Journal of Advances in Modeling Earth Systems 8, no. 2 (June 1, 2016): 917–35. https://doi.org/10.1002/2015MS000578

 

FY 2020 Task III Projects:

Coastal Microscale Dynamics and their Parametrization

Land-Sea breezes are strong air circulations that dominate the wind patterns in coastal zones. They are fueled by the surface temperature differences between the adjacent water and land surfaces. Much remains to be learned about the physics of these circulations, and more importantly about how to represent them in weather and climate models. This is increasingly urgent given the hazards coastal zones are going to face with a changing climate and the potential drastic increase in offshore wind farms. Led by Elie Bou-Zeid, professor of civil and environmental engineering, this project will bridge the gap in physical understanding, apply it to improve forecasting in coastal zones at weather to climate scales, with positive impact for coastal resilience and sustainability.

Gas, Heat, and Spray Fluxes due to Breaking Waves

Luc Deike, assistant professor of mechanical and aerospace engineering and the High Meadows Environmental Institute, will lead research aimed at developing accurate models of gas transfer that can be implemented in ocean and Earth system models, with potential impacts on biogeochemical cycles. Deike and collaborators Brandon Reichl, a GFDL research oceanographer, and AOS Faculty Member Steve Griffies, a GFDL physical scientist, are developing and testing a theoretical framework that explicitly accounts for the role of wave breaking and bubble mediated gas transfer, resolving the very large range of scales involved in the process by a sequence of models, from the atmospheric and wave scales (scales of tens to hundreds of km), to wave breaking, (scales of tens of meters), to air bubble entrainment and bubble dynamics and dissolution (scales of microns to mm).

Dynamic Elemental Stoichiometry in COBALT

Single-celled organisms called phytoplankton absorb sunlight, carbon dioxide, and other nutrients in the ocean's surface and eventually transfer them deep below the surface. This carbon pump strongly influences our atmosphere, climate, and the ocean environment by altering the distribution of carbon, oxygen, and nutrients throughout oceans. In this project, a team of interdisciplinary researchers led by George Hagstrom, associate research scholar in ecology and evolutionary biology, aims to better understand the controls on the carbon pump by modelling how the ratios of carbon:nitrogen:phosphorus in phytoplankton vary with environmental and ecological conditions. Usually modelled as constant, recent laboratory and field data suggests that phytoplankton vary their nutrient ratios in response to the environment, becoming extremely efficient at using phosphorus when nutrients are scarce. By capturing dynamic stoichiometry in GFDL's global ocean models, the researchers, including GFDL Research Oceanographers Charles Stock and Jessica Luo and Simon Levin, the James S. McDonnell Distinguished University Professor in Ecology and Evolutionary Biology, will improve their understanding of carbon export in the current ocean and also better predict how marine ecosystems respond to human-caused environmental changes such as pollution or climate change, enabling society to better plan for the future.

Eddies, Biological Pump and Oxygen

A serious threat from global warming and anthropogenic activities is the loss of oxygen in the world’s ocean1. A major concern is the expansion of tropical oxygen minimum zones (OMZ)threatening marine ecosystems and possibly amplifying climate change by producing greenhouse gases. Earth system models currently project dramatically different changes in OMZ volume by the end of the century2,3. In this project, the Resplandy group, led by Laure Resplandy, assistant professor of geosciences and the High Meadows Environmental Institute, uses the cutting-edge high-resolution Earth system model developed at NOAA-GFDL and a suite of coarser models from the Coupled Model Intercomparison Project 6 (CMIP6) to examine the OMZ response to ocean circulation4 and improve prediction of OMZ future evolution under climate change. This work is conducted in collaboration with GFDL Research Oceanographer John Dunne and Jasmin John, a GFDL physical scientist.

References.

  1. Levin, L. A. Manifestation, Drivers, and Emergence of Open Ocean Deoxygenation. Annu. Rev. Mar. Sci. 10, null (2018).
  2. Bopp, L., Resplandy, L., Untersee, A., Mezo, P.L., Kageyama, M., 2017. Ocean (de)oxygenation from the Last Glacial Maximum to the twenty-first century: insights from Earth System models. Phil. Trans. R. Soc. A 375, 20160323.
  3. Resplandy, L., 2018. Will ocean zones with low oxygen levels expand or shrink? Nature 557, 314–315.
  4. Busecke, J.J.M., Resplandy, L., Dunne, J.P., 2019. The Equatorial Undercurrent and the Oxygen Minimum Zone in the Pacific. Geophysical Research Letters 46, 6716–6725.

Validating and Evaluating Nitrification under Climate Change in the Marine Biogeochemical Component (COBALT) of GFDL’s ESM

Nitrification, the microbially mediated oxidation of ammonium to nitrate, controls the availability of different forms of nitrogen to support primary production.  It also results in the formation of nitrous oxide, a potent greenhouse gas.  In this project, Bess Ward, the William J. Sinclair Professor of Geosciences and the High Meadows Environmental Institute, and a team of researchers, including Weiyi Tang, a postdoctoral research associate in geosciences, will assess the sensitivity of marine nitrification to climate/anthropogenic change including warming, ocean acidification and increasing N deposition. The researchers will develop a database of nitrification rate measurements with the goal of improving the representation of nitrification in global models in order to improve models and predictions of the response of marine productivity to ecosystem stress and climate change.

A Statistical Perspective of the Tropical Circulation – Theory and Empirical Support

Tropical deep convection is observed to be organized on a range of spatial and temporal scales. In this project, Stephan Fueglistaler, associate professor of geosciences, and AOS Graduate Student Yi Zhang explore alternatives to the traditional geographic perspective to describe and understand the organization of tropical deep convection. Published results from this project include a theoretical argument why tropical rainfall distribution is expected to become (even) less evenly distributed under global warming (Zhang and Fueglistaler, GRL, 2019), and empirical proof in observations and model simulations (Zhang and Fueglistaler, GRL, 2020) that the subcloud moist static energy in regions of tropical deep convection is equal over land and ocean in all climates (ranging from past cold glacial to future warm climates).

References:

  1. Zhang, Y., S. Fueglistaler, Mechanism for Increasing Tropical Rainfall Unevenness with Global Warming, Geophys. Res. Letts., 46, 14,836–14,843, doi.org/10.1029/ 2019GL086058, 2019.
  2. Zhang, Y., S. Fueglistaler, How tropical convection couples high moist static energy over land and ocean, Geophys. Res. Letts., 47 (2), e2019GL086387, doi:10.1029/2019GL086387, 2020

Solving the Deep Convection Entrainment-Layer Controversy with GFDL’s FV3

The tropical tropopause layer (TTL) - extending roughly from 14km to 19km altitude - plays an important role for climate through the radiative effect of cirrus clouds in the TTL, and by virtue of being the gate to the stratosphere for  atmospheric trace constituents of great importance to the planetary radiative budget, and to stratospheric ozone depletion. In this project, led by Stephan Fueglistaler, associate professor of geosciences, and Lucas Harris, a GFDL physical scientist, the researchers will use existing and new simulations with global high- resolution numerical models (X-SHiELD) to solve the question whether the TTL is fundamentally a “convective entrainment layer” or dominated by forcing from upward propagating waves, and quantify the implications for climate change.

Dynamic Management of Living Marine Resources from Ocean Biogeochemical Observations and Models

The sustainable use and conservation of marine living resources demands innovative approaches to deal with the multiple facets of global change. Earth observing and modeling systems now provide information about the status and short term of evolution of marine biogeochemical variables, like oxygen availability or plankton productivity, that hold the key to anticipate the impacts of environmental change on marine life. Led by Fernando Gonzalez Taboada, an associate research scholar in atmospheric and oceanic sciences, in collaboration with Jorge Sarmiento, the George J. Magee Professor of Geoscience and Geological Engineering, Emeritus, and GFDL Research Oceanographer Charles Stock, this project targets the development of novel approaches that take full advantage of biogeochemical information to enable a better management of marine resources.

Extreme Rainfall and Flooding the Lower Mississippi River Basin

One of the most consequential issues concerning climate change impacts on flooding in the US is whether extreme floods in the Lower Mississippi River are increasing in frequency.  In this project, James Smith, the William and Edna Macaleer Professor of Engineering and Applied Science, and Yibing Su, a graduate student in civil and environmental engineering, will address the following questions: How is rainfall organized in space and time for extreme flood events in the Lower Mississippi River? Can state-of-the-art Earth System Models accurately represent rainfall variability at time and space scales associated with major Lower Mississippi River flood episodes?  What are the principal climate drivers of extreme rainfall in the Lower Mississippi River? and Are extreme floods in the Lower Mississippi River increasing in frequency? A core objective of this project is assessing and enhancing the capabilities of Earth System Models developed by GFDL to simulate extreme convective rainfall. 

 

FY 2019 Task III Projects

Towards a Multi-scale GFDL Ocean Model: Development of Open Boundary Conditions for MOM6
(Enrique Curchitser, Alistair Adcroft, Robert Hallberg)

Gas and Heat Fluxes Due to Breaking Waves
(Luc Deike, Brandon Reichl, Steve Griffies)

Crassulacean Acid Metabolism (CAM) Photosynthesis: A missing Carbon-Water Link Across Tropical and Semi-Arid Biomes in Climate Models
(Amilcare Porporato, Mark Bartlett)

Eddies, Biological Pump and Oxygen in the Pacific Ocean
(Laure Resplandy, John Dunne, Jasmin John, Charles Stock)

Seasonal Predictability of Rapid Intensification in the North Atlantic
(Gabriel Vecchi, Justin Ng,  Shian-Jiann Lin, Lucas Harris)

A Statistical Perspective of the Tropical Circulation - Theory and Empirical Support
(Stephan Fueglistaler, Yi Zhang)

The Impact of Climate Change on the Transmission and Incidence of Directly Transmitted Childhood Disease
(Jessica Metcalf, Rachel Baker)

Evaluating the Biological Carbon Pump in a Water Mass Framework
(Jorge Sarmiento, Graeme MacGilchrist, Steve Griffies, John Dunne)

Urban Impacts on Compound Heatwaves
(Gabriel Vecchi, Jane Baldwin, Michael Oppenheimer, Elena Shevliakova, Sergey Malyshev,
 Daniel Li)