A5023485909- Climate variability and models
- Meteorological Phenomena and Simulations
- Atmospheric and Environmental Gas Dynamics
- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Oceanographic and Atmospheric Processes
- Atmospheric Ozone and Climate
- Tropical and Extratropical Cyclones Research
- Arctic and Antarctic ice dynamics
- Air Quality Monitoring and Forecasting
- Distributed and Parallel Computing Systems
- Plant Water Relations and Carbon Dynamics
- Marine and coastal ecosystems
- demographic modeling and climate adaptation
- Climate Change Policy and Economics
- Air Quality and Health Impacts
- Aeolian processes and effects
- Geological and Geophysical Studies
- Hydrology and Watershed Management Studies
- Hydrology and Drought Analysis
- Geology and Paleoclimatology Research
- Hydrological Forecasting Using AI
- Geophysics and Gravity Measurements
- Parallel Computing and Optimization Techniques
- Marine and fisheries research
Oak Ridge National Laboratory
2016-2025
University of Tennessee at Knoxville
2022
University of California, Irvine
2022
University of Arizona
2022
Hong Kong University of Science and Technology
2022
University of Hong Kong
2022
Princeton University
2010-2011
Texas A&M University
2008
This work documents the first version of U.S. Department Energy (DOE) new Exascale Earth System Model (E3SMv1). We focus on standard resolution fully coupled physical model designed to address DOE mission-relevant water cycle questions. Its components include atmosphere and land (110-km grid spacing), ocean sea ice (60 km in midlatitudes 30 at equator poles), river transport (55 km) models. base configuration will also serve as a foundation for additional configurations exploring higher...
The last decade has seen the success of stochastic parameterizations in short-term, medium-range and seasonal forecasts: operational weather centers now routinely use parameterization schemes to better represent model inadequacy improve quantification forecast uncertainty. Developed initially for numerical prediction, inclusion not only provides estimates uncertainty, but it is also extremely promising reducing longstanding climate biases relevant determining response external forcing. This...
Abstract The Energy Exascale Earth System Model Atmosphere version 1, the atmospheric component of Department Energy's is described. model began as a fork well‐known Community Model, but it has evolved in new ways, and coding, performance, resolution, physical processes (primarily cloud aerosols formulations), testing development procedures now differ significantly. Vertical resolution was increased (from 30 to 72 layers), top extended 60 km (~0.1 hPa). A simple ozone photochemistry predicts...
Abstract This study provides comprehensive insight into the notable differences in clouds and precipitation simulated by Energy Exascale Earth System Model Atmosphere version 0 1 (EAMv1). Several sensitivity experiments are conducted to isolate impact of changes model physics, resolution, parameter choices on these differences. The overall improvement EAMv1 is primarily attributed introduction a simplified third‐order turbulence parameterization Cloud Layers Unified By Binormals (along with...
Abstract This work documents version two of the Department Energy's Energy Exascale Earth System Model (E3SM). E3SMv2 is a significant evolution from its predecessor E3SMv1, resulting in model that nearly twice as fast and with simulated climate improved many metrics. We describe physical lower horizontal resolution configuration consisting 110 km atmosphere, 165 land, 0.5° river routing model, an ocean sea ice mesh spacing varying between 60 mid‐latitudes 30 at equator poles. The...
Abstract Despite advancements in Artificial Intelligence (AI) methods for climate downscaling, significant challenges remain their practicality research. Current AI‐methods exhibit notable limitations, such as limited application downscaling Global Climate Models (GCMs), and accurately representing extremes. To address these challenges, we implement an AI‐based methodology using super‐resolution convolutional neural networks (SRCNN), trained evaluated on 40 years of daily precipitation data...
Abstract The simulated impact of the Atlantic meridional overturning circulation (AMOC) on low-frequency variability Arctic surface air temperature (SAT) and sea ice extent is studied with a 1000-year-long segment control simulation Geophysical Fluid Dynamics Laboratory Climate Model version 2.1. AMOC variations in are found to be significantly anticorrelated anomalies correlated SAT decadal time scales sector Arctic. maximum anticorrelation correlation occur when index leads by one year. An...
Abstract Deep neural networks (DNNs) are implemented in Super‐Parameterized Energy Exascale Earth System Model (SP‐E3SM) to imitate the shortwave and longwave radiative transfer calculations. These DNNs were able emulate radiation parameters with an accuracy of 90–95% at a cost 8–10 times cheaper than original parameterization. A comparison time‐averaged fluxes prognostic variables manifested qualitative quantitative similarity between DNN emulation It has also been found that differences...
This work documents version two of the Department Energy's Energy Exascale Earth System Model (E3SM). E3SM 2 (E3SMv2) is a significant evolution from its predecessor E3SMv1, resulting in model that nearly twice as fast and with simulated climate improved many metrics. We describe physical lower horizontal resolution configuration consisting 110 km atmosphere, 165 land, 0.5° river routing model, an ocean sea ice mesh spacing varying between 60 mid-latitudes 30 at equator poles. The...
This work documents version two of the Department Energy’s Energy Exascale Earth System Model (E3SM). E3SM 2 (E3SMv2) is a significant evolution from its predecessor E3SMv1, resulting in model that nearly twice as fast and with simulated climate improved many metrics. We describe physical lower horizontal resolution configuration consisting 110 km atmosphere, 165 land, 0.5° river routing model, an ocean sea ice mesh spacing varying between 60 mid-latitudes 30 at equator poles. The...
Abstract We present the first application of a fast super resolution convolutional neural network (FSRCNN) based approach for downscaling earth system model (ESM) simulations. Unlike other SR approaches, FSRCNN uses same input feature dimensions as low input. This allows it to have smaller convolution layers, avoiding over‐smoothing, and reducing computational costs. adapt improve reconstruction on ESM data, we term FSRCNN‐ESM. use high‐resolution (∼0.25°) monthly averaged output five...
Abstract Global climate models (GCMs) underestimate the observed trend in tropical expansion. Recent studies partly attribute it to black carbon (BC) aerosols, which are poorly represented GCMs. We conduct a suite of idealized experiments with Community Atmosphere Model version 4 coupled slab ocean model forced increasing BC concentrations covering large swath estimated range current radiative forcing while maintaining their spatial distribution. The Northern Hemisphere (NH) tropics expand...
Abstract The impacts of absorbing aerosols on global climate are not completely understood. This paper presents the results idealized experiments conducted with Community Atmosphere Model, version 4 (CAM4), coupled to a slab ocean model (CAM4–SOM) simulate response increases in tropospheric black carbon (BC) by direct and semidirect effects. CAM4-SOM was forced 0, 1×, 2×, 5×, 10× an estimate present day concentration BC while maintaining estimated spatial vertical distribution....
Abstract The monsoons in Pakistan have been exceptionally harsh recent decades, resulting extraordinary drought conditions and record flooding events. changing characteristics of extreme events are widely attributed to climate change. However, given this region’s long history floods droughts, the role natural variability cannot be rejected without a careful diagnosis. Here, we examine how oceanic atmospheric has contributed unusual precipitation distributions West South Asia. Variations sea...
Abstract The role of the wind–evaporation–sea surface temperature (WES) feedback in propagation high-latitude cooling signal to tropical oceans using NCAR atmospheric Community Climate Model (CCM3) coupled thermodynamically a slab-ocean model (SOM) is studied. Abruptly imposed additional Northern Hemispheric sea ice cover equivalent Last Glacial Maximum (LGM; 18 kyr BP) causes Hemisphere–wide cooling, as well generation and amplification an anomalous cross-equatorial meridional SST dipole...
Abstract The role of the wind–evaporation–sea surface temperature (WES) feedback in low-frequency natural variability tropical Atlantic is studied using an atmospheric global climate model—the NCAR Community Climate Model, version 3 (CCM3)—thermodynamically coupled to a slab ocean model (SOM). modified suppress WES and compared control run. Singular value decomposition (SVD) analysis over reveals that meridional mode Ocean amplified presence feedback. In its absence, still exists, but with...
Precipitation extremes have tangible societal impacts. Here, we assess if current state of the art global climate model simulations at high spatial resolutions (0.35° × 0.35°) capture observed behavior precipitation in past few decades over continental US. We design a correlation-based regionalization framework to quantify extremes, where samples extreme events for grid box may also be drawn from neighboring boxes with statistically equal means and significant temporal correlations....
Abstract While black carbon aerosols (BC) are believed to modulate the Indian monsoons, radiative forcing estimate of BC suffers from large uncertainties globally. We analyze a suite idealized experiments forced with range concentrations that span swath latest estimates its global forcing. Within those bounds uncertainty, summer precipitation over region increases nearly linearly increase in burden. The linearity holds even as concentration is increased levels resembling hypothesized nuclear...
Abstract. The E3SM Diagnostics Package (E3SM Diags) is a modern, Python-based Earth system model (ESM) evaluation tool (with Python module name e3sm_diags), developed to support the Department of Energy (DOE) Exascale System Model (E3SM). Diags provides wide suite tools for evaluating native output, as well ESM data on regular latitude–longitude grids, including output from Coupled Intercomparison Project (CMIP) class models. modeled after National Center Atmospheric Research (NCAR)...
A strict throughput requirement has placed a cap on the degree to which we can depend execution of single, long, fine spatial grid simulations explore global atmospheric climate behavior. Alternatively, running an ensemble short is computationally more efficient. We test null hypothesis that statistics full-complexity model derived from independent simulation equivalent equilibrated long simulation. The ensembles statistically distinguishable in terms distribution annual means, largely due...
Effective utilization of novel hybrid architectures pre-exascale and exascale machines requires transformations to global climate modeling systems that may not reproduce the original model solution bit-for-bit. Round-off level differences grow rapidly in these non-linear chaotic systems. This makes it difficult isolate bugs/errors from innocuous growth expected round-off differences. Here, we apply two modern multivariate sample equality distribution tests evaluate statistical...