A5008242217- Climate variability and models
- Meteorological Phenomena and Simulations
- Plant Water Relations and Carbon Dynamics
- Cryospheric studies and observations
- Fire effects on ecosystems
- Atmospheric and Environmental Gas Dynamics
- Climate change and permafrost
- Groundwater and Isotope Geochemistry
- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Urban Heat Island Mitigation
- Tree-ring climate responses
- Landslides and related hazards
- Precipitation Measurement and Analysis
- Hydrology and Watershed Management Studies
- Geophysics and Gravity Measurements
- Conservation, Biodiversity, and Resource Management
- Climate change impacts on agriculture
- Effects of Environmental Stressors on Livestock
- Remote Sensing and Land Use
- Oceanographic and Atmospheric Processes
- Hydrology and Drought Analysis
- Remote Sensing in Agriculture
- Rangeland Management and Livestock Ecology
- Rangeland and Wildlife Management
San Diego State University
2015-2024
University of California, Los Angeles
2006-2016
University of California System
2014-2015
UCLA Health
2012-2014
Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are fundamental cause consequence global change, impacting people the biophysical systems on which they depend. As part newly emerging Anthropocene, marked by human-caused climate change radical changes to ecosystems, danger increasing, fires having increasingly devastating impacts human health, infrastructure, ecosystem services. Increasing vexing problem requires...
Abstract A global and seasonal assessment of regions the earth with strong climate–vegetation biophysical process (VBP) interactions is provided. The presence VBP degree effects on climate were assessed based skill simulations observed precipitation by two general circulation models atmosphere coupled to three land varying degrees complexity in representation. simulated estimated be about 10% globally 40% over land; strongest impacts monsoon regions. Among these, highest West African, South...
Abstract Two important factors that control snow albedo are grain growth and presence of light‐absorbing impurities (aerosols) in snow. However, current regional climate models do not include such processes a physically based manner their land surface models. We improve calculations the Simplified Simple Biosphere (SSiB) model coupled with Weather Research Forecasting (WRF) (RCM), by incorporating SNow ICe And Radiative (SNICAR) scheme. SNICAR simulates evolution due to aging aerosols The is...
The Brazilian Amazon provides important hydrological cycle functions, including precipitation regimes that bring water to the people and environment are critical moisture recycling transport, represents an variable for climate models simulate accurately. This paper evaluates performance of 13 Coupled Model Intercomparison Project Phase 6 (CMIP6) models. is done by discussing results from spatial pattern mapping, Taylor diagram analysis skill score, annual climatology comparison, cumulative...
Abstract This study explores the role of vegetation biophysical processes (VBPs) in structure and evolution South American monsoon system (SAMS) with an emphasis on precipitation field. The approach is based comparing ensemble simulations by National Centers for Environmental Prediction general circulation model (GCM) which land surface parameterization one includes explicit representation calculation fluxes while other does not [GCM/Simplified Simple Biosphere Model (SSiB) GCM/Soil,...
Abstract Tropical rainforests provide essential ecosystem services to agricultural areas, including moisture recycling. In the Amazon basin, drought frequency has increased in late 20th and early 21st centuries, but role of forests, ocean, nonforested areas causing or mitigating not been determined. Using a precipitationshed tracking framework, we quantify contribution sources evaporation rainfall Rondônia Brazilian Amazon. Forests account for ∼48% annual on average, more than half forest...
Abstract The National Centers for Environmental Prediction (NCEP) ETA regional circulation model (RCM) was one‐way nested in the T62 NCEP general a series of 3‐month simulations austral summer and winter over South America (SA). intensity‐scale verification technique (ISVT), based on scale decomposition precipitation skill score energy relative difference, used to quantitatively assess dynamic‐downscaling ability seasonal inter‐annual difference. ISVT showed that RCM able add value rainfall...
Recurrent drought and associated heatwave episodes are important features of the US climate. Many studies have examined connection between ocean surface temperature changes conterminous droughts. However, remote effects large-scale land variability, over shorter but still considerable distances, on regional droughts been largely ignored. The present study combines two types evidence to address these effects: climate observations model simulations. Our analysis observational data shows that...
The present study demonstrates that (1) the simulation of South American warm season (December–February) climate by an atmospheric general circulation model (AGCM) is sensitive to representation land surface processes, (2) sensitivity not confined "hot spot" in Amazonia, and (3) upgrading those processes can produce a significant improvement AGCM performance. reasons for higher success are investigated based on comparisons between observational datasets simulations coupled either simple...
Abstract Rainforest in protected areas the Brazilian Amazon is at risk due to increasing economic pressures and recent weakening of environmental agencies legislation by federal administration. This study examines impacts deforestation on dry‐season precipitation state Rondônia located southwestern Amazon. Regional‐climate model simulations indicate that clearing forests would result substantial changes surface energy balance, including increased sensible decreased latent heat flux....
Southern California has seen a resurgence of winegrowing regions in the past few decades, however future winegrape climatic suitability area not been exhaustively explored. This study evaluated climate for cultivation and potential global warming impacts on southern California's through series high-resolution surface air temperature precipitation projections obtained with WRF-SSIB regional model. Results reveal that by mid-21st-century will increase approximately 1.2 °C, while average...
The present study utilizes three high-resolution simulations from the Regional Climate Model version 4 (RegCM4) to examine late 21st century changes (2080–2099) in West African Monsoon (WAM) features. A set of Earth System Models are utilized provide initial and lateral boundary conditions RegCM4 experiments. Our analysis focuses on seasonal mean WAM large-scale dynamical features, along with their connections summer monsoon precipitation. In historical period, simulation ensemble means...
Wildfire burn severity has important implications for postfire vegetation recovery and boundary-layer climate. We used a collection of Moderate Resolution Imaging Spectroradiometer (MODIS) datasets to investigate the impact (relative differenced Normalized Burn Ratio, RdNBR) on (Enhanced Vegetation Index, EVI), albedo change, land surface temperature in seven California ecoregions, including: Southern Mountains (SCM), Coast (SCC), Central Foothills (CCF), Klamath (K), Cascades (C), Eastern...
Abstract Prioritizing watershed management interventions relies on delineating homogeneous precipitation regions. In this study, we identify these regions in the Brazilian Legal Amazon based magnitude of Sen’s Slope trends using annual data from September to August, employing Google Earth Engine platform. Utilizing silhouette method, determine four distinct clusters representing zones patterns. Cluster 0 exhibits a significant median increase 3.20 mm year −1 over period 1981 2020. 1 shows...
Farmworkers, the frontline workers of our food system, are often exposed to heat stress that is likely increase in frequency and severity due climate change. Irrigation can either alleviate or exacerbate stress, quantification which crucial intensely irrigated agricultural lands such as Imperial Valley southern California. We investigate impact irrigation on wet bulb globe temperature (WBGT), a key indicator exposure humans, using validated high-resolution Weather Research Forecasting (WRF)...
Abstract MODIS data were used in conjunction with 600 ground survey points to create a 500 m resolution land cover product of Mali. It improves upon previously published products for this region and accuracy. Of particular importance is the ability detect small-scale, but important, wetland features such as rice cultivation areas. A combination classical vegetation type structure, meteorological data, remote sensing was quantify relationship between climate along sensitive Sahel...