A5053500645- Climate variability and models
- Cryospheric studies and observations
- Meteorological Phenomena and Simulations
- Hydrology and Watershed Management Studies
- Climate change and permafrost
- Atmospheric and Environmental Gas Dynamics
- Flood Risk Assessment and Management
- Tropical and Extratropical Cyclones Research
- Hydrology and Drought Analysis
- Fire effects on ecosystems
- Hydrological Forecasting Using AI
- Landslides and related hazards
- Oceanographic and Atmospheric Processes
- Ionosphere and magnetosphere dynamics
- Precipitation Measurement and Analysis
- Anomaly Detection Techniques and Applications
- Water-Energy-Food Nexus Studies
- Smart Materials for Construction
- Ethics and Social Impacts of AI
- Parallel Computing and Optimization Techniques
- Species Distribution and Climate Change
- Big Data Technologies and Applications
- Urban Heat Island Mitigation
- Arctic and Antarctic ice dynamics
- Environmental Policies and Emissions
Lawrence Berkeley National Laboratory
2017-2025
University of California, Davis
2015-2024
Lawrence Livermore National Laboratory
2024
Thuyloi University
2024
United States Geological Survey
2022
Pacific Island Ecosystems Research Center
2022
University of California, Los Angeles
2022
University of Nevada, Reno
2022
Iowa State University
2020
University of California, Berkeley
2018
ABSTRACT Regional climate modeling addresses our need to understand and simulate climatic processes phenomena unresolved in global models. This paper highlights examples of current approaches innovative uses regional that deepen understanding the system. High-resolution models are generally more skillful simulating extremes, such as heavy precipitation, strong winds, severe storms. In addition, research has shown fine-scale features mountains, coastlines, lakes, irrigation, land use, urban...
Abstract In this paper, the recently developed variable‐resolution option within Community Earth System Model (VR‐CESM) is assessed for long‐term regional climate modeling of California at 0.25° (∼28 km) and 0.125° (∼14 horizontal resolutions. The mean climatology near‐surface temperature precipitation analyzed contrasted with reanalysis, gridded observational data sets, a traditional model (RCM)—the Weather Research Forecasting (WRF) model. Statistical metrics evaluation tests differential...
The California drought of 2012-2016 was a record-breaking event with extensive social, political, and economic repercussions. impacts were widespread exposed the difficulty in preparing for effects prolonged dry conditions. Although lessons from this drove important changes to state law policy, there is little doubt that climate change will only exacerbate future droughts. To understand character drought, paper examines recent period retrospectively prospectively, is, as it occurred...
Abstract The location, timing, and intermittency of precipitation in California make the state integrally reliant on winter-season snowpack accumulation to maintain its economic agricultural livelihood. Of particular concern is that has shown a net decline across western United States over past 50 years, resulting major uncertainty water-resource management heading into next century. Cutting-edge tools are available help navigate preemptively plan for these uncertainties. This paper uses...
The Atmospheric River (AR) Tracking Method Intercomparison Project (ARTMIP) is a community effort to systematically assess how the uncertainties from AR detectors (ARDTs) impact our scientific understanding of ARs. This study describes ARTMIP Tier 2 experimental design and initial results using Coupled Model (CMIP) Phases 5 6 multi-model ensembles. We show that statistics given ARDT in CMIP5/6 historical simulations compare remarkably well with MERRA-2 reanalysis. In future simulations, most...
Abstract Until recently, the El Niño–Southern Oscillation (ENSO) was considered a reliable source of winter precipitation predictability in western US, with historically strong link between extreme Niño events and extremely wet seasons. However, 2015–2016 challenged our understanding ENSO-precipitation relationship. California near-average during Niño, which characterized by warm sea surface temperature (SST) anomalies similar magnitude compared to 1997–1998 1982–1983 events. We demonstrate...
Abstract Atmospheric rivers (ARs) can be a boon and bane to water resource managers as they have the ability replenish reserves, but also generate million‐to‐billion‐dollar flood damages. To investigate how anthropogenic climate change may influence AR characteristics in coastal western United States by end century, we employ suite of novel tools such variable resolution Community Earth System Model (VR‐CESM), TempestExtremes detection algorithm, Ralph, Rutz, et al. (2019,...
Abstract The reliability of climate simulations and projections, particularly in the regions with complex terrains, is greatly limited by model resolution. In this study we evaluate variable‐resolution Community Earth System Model (VR‐CESM) a high‐resolution (0.125°) refinement over Rocky Mountain region. VR‐CESM results are compared observations, as well CESM simulation at quasi‐uniform 1° resolution (UNIF) Canadian Regional Climate version 5 (CRCM5) 0.11° We find that effective capturing...
Abstract Atmospheric rivers (ARs) are long and narrow filaments of vapor transport that responsible for most poleward moisture outside the tropics. Many AR detection algorithms have been developed to automatically identify ARs in climate data. The diversity these has introduced appreciable uncertainties quantitative measures properties thereby impedes construction a unified internally consistent climatology ARs. This paper compares nine global from perspective lifecycles following...
Atmospheric rivers (ARs) are critical to the hydrological cycle of western United States with both favorable and formidable impacts society based on their landfalling characteristics. In this study, we provide a first-of-its-kind evaluation how ARs may respond several stabilized warming scenarios. To do combine recently developed AR detection workflow an ensemble uniform high-resolution (0.25°) Community Earth System Model simulations designed facilitate attribution extreme events global...
Abstract We introduce variable‐resolution enabled Community Earth System Model (VR‐CESM) results simulating historical and future climate conditions at 28 km over South America 14 the Andes. Three 30‐year simulations are performed: a historic (1985–2014), near (2030–2059), an end‐century (2070–2099) simulation under RCP8.5 scenario. Historic compare favourably to several temperature precipitation reanalysis products, though local biases present, particularly during austral summer. Future...
Abstract Societies and ecosystems within downstream of mountains rely on seasonal snowmelt to satisfy their water demands. Anthropogenic climate change has reduced mountain snowpacks worldwide, altering magnitude timing. Here the global warming level leading widespread persistent snowpack decline, termed low-to-no snow, is estimated for world’s most latitudinally contiguous range, American Cordillera. We show that a combination dynamical, thermodynamical hypsometric factors results in an...
Abstract Increasing wildfire and declining snowpacks in mountain regions threaten water availability. We combine satellite‐based fire detections with snow seasonality classifications to examine activity California's seasonal ephemeral zones. find a nearly tenfold increase during 2020–2021 versus 2001–2019. Accumulation season broadband albedo declined 25%–71% at two burned sites (2021 2022) according in‐situ data relative un‐burned conditions, greater declines associated increased burn...
Abstract. This paper provides an overview of the United States (US) Department Energy's (DOE's) Energy Exascale Earth System Model version 2 (E3SMv2) fully coupled regionally refined model (RRM) and documents overall atmosphere, land, river results from Coupled Intercomparison Project 6 (CMIP6) DECK (Diagnosis, Evaluation, Characterization Klima) historical simulations – a first-of-its-kind set climate production using RRM. The North American (NA) RRM (NARRM) is developed as high-resolution...
Abstract The 1997 New Year's flood event was the most costly in California's history. This compound extreme driven by a category 5 atmospheric river that led to widespread snowmelt. Extreme precipitation, snowmelt, and saturated soils produced heavy runoff causing inundation Sacramento Valley. study recreates using Regionally Refined Mesh capabilities of Energy Exascale Earth System Model (RRM‐E3SM) under prescribed ocean conditions. Understanding processes events informs practical efforts...
Abstract The mountains of the Western United States provide a vital natural service through storage and release mountain snowpack, lessening impacts seasonal aridity satiating summer water demand. However, climate change continues to undermine these important processes. To understand how snowpack may in headwaters California's major reservoirs, North American Coordinated Regional Climate Downscaling Experiment is analyzed assess peak volume, timing, accumulation rate, melt snow season length...
Abstract Mountains are natural dams that impede atmospheric moisture transport and water towers cool, condense, store precipitation. They essential in the western United States where precipitation is seasonal, snowpack needed to meet demand. With anthropogenic climate change increasingly threatening mountain snowpack, there a pressing need better understand driving climatological processes. However, coarse resolution typical of modern global models renders them largely insufficient for this...
Abstract Variable‐resolution global climate models (VRGCMs) are a dynamical downscaling method that can reach spatiotemporal scales needed for regional assessments. Over the years, several users of VRGCMs have assumed where location and extent refinement domain should be based on knowledge prevailing storm tracks resolution dependence important processes (e.g., atmospheric rivers [ARs] orographic uplift), but effect high‐resolution size simulation downstream hydroclimatic phenomena has not...
Abstract. Snow droughts are commonly defined as below-average snowpack at a point in time, typically 1 April the western United States (wUS). This definition is valuable for interpreting state of but obscures temporal evolution snow drought. Borrowing from dynamical systems theory, we applied phase diagrams to visually examine daily water equivalent (SWE) and accumulated precipitation conditions maritime, intermountain, continental climates wUS using station observations well spatially...
Abstract Mountains play an outsized role in water resource availability, and the amount timing of they provide depend strongly on temperature. To that end, we ask question: How well are atmospheric models capturing mountain temperatures? We synthesize results showing high-resolution, regionally relevant climate produce 2-m air temperature (T2m) measurements colder than what is observed (a “cold bias”), particularly snow-covered midlatitude ranges during winter. find common cold biases 44...
Abstract. In this study, the resolution dependence of simulated Greenland ice sheet surface mass balance (GrIS SMB) in variable-resolution Community Earth System Model (VR-CESM) is investigated. Coupled atmosphere–land simulations are performed on two regionally refined grids over at 0.5∘ (∼55 km) and 0.25∘ (∼28 km), maintaining a quasi-uniform 1∘ (∼111 rest globe. On grids, SMB accumulation zone significantly improved compared to airborne radar situ observations, with general wetting (more...
Abstract Atmospheric rivers (ARs) account for a large portion of winter precipitation in the western US. To evaluate sources AR and predictability at subseasonal‐to‐seasonal timescales, we examine relationships between two climate modes, El Niño/Southern Oscillation (ENSO) Madden‐Julian oscillation (MJO), hydroclimate Our analysis uses ensemble Weather Research Forecast (WRF) model simulations from 1981 to 2017, facilitating assessment uncertainty mode‐AR relationship due variability short...