The Cooperative Institute for Modeling the Earth System (CIMES) has announced awards totaling $612,000 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 2022 to 2023 and foster research, teaching, and mentorship in Earth system science.
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, the researchers expect to collaborate closely with Paul Ginoux, Larry Horowitz and Fabien Paulot at GFDL.
Development and Parameterization of a Trait-Based Model of Zooplankton Diversity for Marine Food Web and Climate Feedback Studies
Tiny marine animals only a millimeter to centimeter in size exert an enormous influence on ocean’s food webs and are a primary conduit for the transfer of carbon from the atmosphere to the deep ocean. These so-called zooplankton are also incredibly diverse in their form, sizes, rates of feeding, and tolerance for temperature and oxygen levels. How is this diversity related to the variation in these ocean conditions? How might that diversity change as the oceans get warmer and less oxygen-rich? Answering these questions will require new types of models that represent a wide array of zooplankton species and the traits that describe their distinct physiological responses to environmental conditions. Led by Curtis Deutsch, professor of geosciences and the High Meadows Environmental Institute, in collaboration with GFDL Research Oceanographer Charles Stock and Justin Penn, a postdoctoral research associate in geosciences, this project will take a new approach toward constructing such models, so that the researchers can better understand how zooplankton traits sustain their species diversity, how that diversity will be impacted by a rapidly changing ocean, and how those biological changes may in turn impact the ocean at a global scale.
Titrating the Impact of Low and High Frequency Perturbations of Transmission of
Infectious Disease: Positioning the Role of Climate
The climate can affect the transmission of infectious diseases. Cold temperatures increase the transmission of some viruses like SARS-COV-2, rain can modulate breeding opportunities for important vectors (e.g., mosquitos) of malaria, flooding may increase the range of exposure of pathogens like cholera, and so on. All of these climate drivers change over the course of years and decades. Seasonal fluctuations are the most salient, with repeatable patterns occurring over the course of a year, but there are also multi-annual cycles, such as El Nino. These changes will intersect with the fact that exposure to many infections is immunizing, so that once infected, individuals are protected, at least for some period of time from reinfection. This will mean that increases in transmission (driven by the climate) will be followed by depletion of susceptible individuals who can acquire the infection, and thus reduce the spread of infection. In this project, a team of researchers, led by Jessica Metcalf, associate professor of ecology and evolutionary biology and public affairs, will explore how this fluctuating depletion of susceptible individuals intersects with fluctuations in transmission to shape the course of epidemics over short and long time-scales. We will focus our analysis on simulations (to explore the range of the possible) alongside probing data on the drivers of respiratory syncytial virus (a directly transmitted childhood infection) and dengue (a vector born infection) to understand how climate effects on transmission and the dynamics of susceptibility intersect to shape the burden of infection under current and future climates.
Team Members: Jessica Metcalf, EEB, School of Public and International Affairs; Bryan Grenfell, EEB, School of Public and International Affairs; Keith Dixon, NOAA/GFDL; Gabriel Vecchi, GEO, HMEI; Rachel Baker, HMEI; Jamie Caldwell, HMEI; Inga Holmdahl, HMEI
The cold climate of Earth’s ice ages was partly due to a low concentration of CO2 in the ice age atmosphere, leading to a weaker greenhouse effect during the ice ages. In the 1980s, AOS and GFDL scientists first hypothesized that the lower CO2 concentration of the ice age atmosphere was due to the Southern Ocean, the expansive ocean region surrounding Antarctica. Princeton geoscientists Daniel Sigman, Curtis Deutsch, and Laure Resplandy will collaborate with GFDL scientists to pursue this hypothesis through comparison of GFDL climate model simulations with paleoceanographic data from the Southern Ocean, including data generated in Sigman’s lab. The findings may have implications for whether and how the ocean’s ongoing uptake of anthropogenic CO2 and global warming heat will change as climate continues to warm.
Global Warming Simulations at Convection-Resolving Resolution Globally
The advent of global storm-resolving atmospheric model simulations allows scientists to study important processes in the climate system - from storms, coupling between large-scale tropical waves and convection, to processes that may affect climate sensitivity such as convective aggregation - at a scale where convection is explicitly resolved. Such simulations are still numerically very expensive and not widely accessible to researchers yet. A team of interdisciplinary researchers, led by Stephan Fueglistaler, professor of geosciences, will use the GFDL X-SHiELD model to run a small number of year-long integrations (thus covering the full annual cycle) at present day climatic conditions, and in a simple global warming configuration with uniformly increased sea surface temperature. These runs will be complemented with simulations at reduced horizontal resolution to study on the one hand the differences due to resolution, and on the other hand bracket uncertainty due to internal variability. The simulations will be made available to the CIMES community and may serve as a baseline for further specific experiments.
PI: Stephan Fueglistaler, GEO; Co-Investigators: Gabriel Vecchi, GEO, HMEI; Michael Oppenheimer, GEO, HMEI, School of Public and International Affairs; Jessica Metcalf, EEB, School of Public and International Affairs; Bryan Grenfell, EEB, School of Public and International Affairs; Lucas Harris, GFDL
Extreme Rainfall and Flooding
One of the most consequential issues concerning climate change impacts on flooding in the US is whether extreme floods 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? What are the principal climate drivers of extreme rainfall 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 flood episodes? In addition to flooding in the Lower Mississippi River, analyses will assess rainfall and flood extremes from the remnants of Hurricane Ida in the Northeastern US.
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, the University of California, Irvine, 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.
Gabriel Vecchi, Princeton Department of Geosciences and High Meadows Environmental Institute; Wenchang Yang, Princeton Department of Geosciences; 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, University of California, Irvine; Dan Li, Boston University
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. https://doi.org/10.1029/2018EF000989
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.