A5059246177- Meteorological Phenomena and Simulations
- Climate variability and models
- Precipitation Measurement and Analysis
- Tropical and Extratropical Cyclones Research
- Atmospheric and Environmental Gas Dynamics
- Atmospheric chemistry and aerosols
- Cryospheric studies and observations
- Wind and Air Flow Studies
- Atmospheric aerosols and clouds
- Ocean Waves and Remote Sensing
- Geophysics and Gravity Measurements
- Soil Moisture and Remote Sensing
- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Fashion and Cultural Textiles
- Fire effects on ecosystems
- Air Quality Monitoring and Forecasting
- Flood Risk Assessment and Management
- Radio Wave Propagation Studies
- Marine and Coastal Research
- Cultural and Historical Studies
- Diverse Approaches in Healthcare and Education Studies
- Computational Physics and Python Applications
- Anomaly Detection Techniques and Applications
- Electronic Health Records Systems
Office of Science
2020-2025
University of Oklahoma
2015-2024
Office of Multidisciplinary Activities
2023
Boston University
2023
National Oceanic and Atmospheric Administration
2021-2022
NOAA National Weather Service
2022
NOAA National Severe Storms Laboratory
2019-2020
Cooperative Institute for Mesoscale Meteorological Studies
2013-2020
Abstract The National Oceanic and Atmospheric Administration (NOAA) has developed an advanced regional air quality prediction system (AQPS) within the Unified Forecast System (UFS) framework to improve representations of wildfire emissions their impacts on predictions. This innovative integrates Environmental Protection Agency’s (EPA) Community Multiscale Air Quality (CMAQ) model as a column chemistry with UFS-based atmospheric model, operating in online mode. calculation gas particulate...
Abstract A radar simulator for polarimetric variables, including reflectivities at horizontal and vertical polarizations, the differential reflectivity, specific phase, has been developed. This serves as a test bed developing testing forward observation operators of variables that are needed when directly assimilating these into storm-scale numerical weather prediction (NWP) models, using either variational or ensemble-based assimilation methods. The takes input results high-resolution NWP...
Abstract A new general polarimetric radar simulator for nonhydrostatic numerical weather prediction (NWP) models has been developed based on rigorous scattering calculations using the T-matrix method reflectivity, differential specific phase, and copolar cross-correlation coefficient. continuous melting process accounts entire spectrum of varying density dielectric constants. This is able to simulate measurements at frequency bands can take as input prognostic variables high-resolution NWP...
Abstract The low levels of supercell forward flanks commonly exhibit distinct differential reflectivity (ZDR) signatures, including the low-ZDR hail signature and high-ZDR “arc.” ZDR arc has been previously associated with size sorting raindrops in presence vertical wind shear; here this model is extended to include hail. Idealized simulations a storm observed by Norman, Oklahoma (KOUN), polarimetric radar on 1 June 2008 are performed using multimoment bulk microphysics scheme, which allowed...
Abstract A data assimilation system based on the ensemble square-root Kalman filter (EnSRF) is extended to include additional capability of assimilating polarimetric radar variables. It used assess impact observations convective storm analysis in Observing System Simulation Experiment (OSSE) framework. The variables considered differential reflectivity ZDR, difference Zdp, and specific phase KDP. To simulate observational more realistically, a new error model introduced for characterizing...
Abstract The performance of ensemble Kalman filter (EnKF) analysis is investigated for the tornadic supercell on 29–30 May 2004 in Oklahoma using a dual-moment (DM) bulk microphysics scheme Advanced Regional Prediction System (ARPS) model. comparison results single-moment (SM) and DM schemes evaluates benefits one over other during storm analysis. Observations from single operational Weather Surveillance Radar-1988 Doppler (WSR-88D) are assimilated polarimetric WSR-88D Norman, (KOUN), used...
Abstract One of the goals National Science Foundation Engineering Research Center (ERC) for Collaborative Adaptive Sensing Atmosphere (CASA) is to improve storm-scale numerical weather prediction (NWP) by collecting data with a dense X-band radar network that provides high-resolution low-level coverage, and assimilating such into NWP models. During first spring storm season after deployment four radars in CASA Integrated Project-1 (IP-1) southwest Oklahoma, tornadic mesoscale convective...
Abstract Microphysics parameterization becomes increasingly important as the model grid spacing increases toward convection-resolving scales. The performance of several partially or fully two-moment (2M) schemes within Weather Research and Forecasting (WRF) Model, version 3.5.1, chosen because their well-documented advantages over one-moment (1M) schemes, is evaluated with respect to ability in producing well-known polarimetric radar signatures found supercell storms. Such include ZDR KDP...
Abstract Led by NOAA’s Storm Prediction Center and National Severe Storms Laboratory, annual spring forecasting experiments (SFEs) in the Hazardous Weather Testbed test evaluate cutting-edge technologies concepts for improving severe weather prediction through intensive real-time evaluation activities. Experimental forecast guidance is provided collaborations with several U.S. government academic institutions, as well Met Office. The purpose of this article to summarize activities, insights,...
Abstract One primary goal of annual Spring Forecasting Experiments (SFEs), which are coorganized by NOAA’s National Severe Storms Laboratory and Storm Prediction Center conducted in the Oceanic Atmospheric Administration’s (NOAA) Hazardous Weather Testbed, is documenting performance characteristics experimental, convection-allowing modeling systems (CAMs). Since 2007, number CAMs (including CAM ensembles) examined SFEs has increased dramatically, peaking at six different ensembles 2015....
Abstract Polarimetric radar variables are simulated from members of the 2013 Center for Analysis and Prediction Storms (CAPS) Storm-Scale Ensemble Forecasts (SSEF) with varying microphysics (MP) schemes compared observations. The polarimetric provide information on hydrometeor types particle size distributions (PSDs), neither which can be obtained through reflectivity (Z) alone. simulator pays close attention to how each MP scheme [including single- (SM) double-moment (DM) schemes] treats...
After decades of research and development, the WSR-88D (NEXRAD) network in United States was upgraded with dual-polarization capability, providing polarimetric radar data (PRD) that have potential to improve weather observations, quantification, forecasting, warnings. The networks China other countries are also being capability. Now, polarimetry technology having matured, PRD available both nationally globally, it is important understand current status future challenges opportunities. impact...
Abstract Doppler radar data are assimilated with an ensemble Kalman Filter (EnKF) in combination a double-moment (DM) microphysics scheme order to improve the analysis and forecast of microphysical states precipitation structures within mesoscale convective system (MCS) that passed over western Oklahoma on 8–9 May 2007. Reflectivity radial velocity from five operational Weather Surveillance Radar-1988 (WSR-88D) S-band radars as well four experimental Collaborative Adaptive Sensing Atmosphere...
Abstract In recent studies, the authors have successfully demonstrated ability of an ensemble Kalman filter (EnKF), assimilating real radar observations, to produce skillful analyses and subsequent ensemble-based probabilistic forecasts for a tornadic mesoscale convective system (MCS) that occurred over Oklahoma Texas on 9 May 2007. The current study expands upon this prior work, performing experiments case larger domain using nested-grid EnKF, which accounts uncertainties through initial...
Abstract This study examines the ability of a storm-scale numerical weather prediction (NWP) model to predict precipitation and mesovortices within tornadic mesoscale convective system that occurred over Oklahoma on 8–9 May 2007, when is initialized from ensemble Kalman filter (EnKF) analyses including data four Engineering Research Center for Collaborative Adaptive Sensing Atmosphere (CASA) X-band five Weather Surveillance Radar-1988 Doppler (WSR-88D) S-band radars. Ensemble forecasts are...
In this paper, we present synthetic data generation framework for flood hazard detection system. For high fidelity and quality, characterize several real-world properties into virtual world simulate the situation by controlling them. sake of efficiency, recent generative models in image-to-3D urban city synthesis are leveraged to easily composite environments so that avoid bias due hand-crafted manner. Based on our framework, build dataset with 5 levels, dubbed MultiFloodSynth which contains...
Abstract Despite recent advances in storm-scale ensemble NWP, short-term (0–90 min) explicit forecasts of severe hail remain a major challenge as result the fast evolution and short time scales hail-producing convective storms substantial uncertainty associated with microphysical representation hail. In this study, 0–90-min for supercell 20 May 2013 over central Oklahoma are examined verified, goals 1) evaluating forecast performance, 2) comparing advantages limitations different fields...
Abstract A high-resolution numerical model and polarimetric forward operator allow one to examine simulated convective storms from the perspective of observable radar quantities, enabling a better comparison modeled observed deep moist convection. Part I this two-part study described used for all simulations examined structure evolution rings reduced copolar cross-correlation coefficient (i.e., ρ hv rings). The microphysical upward extensions enhanced differential reflectivity ( Z DR columns...
Abstract Capabilities to directly assimilate radar radial velocity ( V r ) and reflectivity Z data are implemented within the operational GSI assimilation (DA) framework coupled with new stand‐alone regional (SAR) FV3 model. The effectiveness performance of 3DVar, EnKF, hybrid En3DVar methods evaluated a storm cluster over U.S. Central Plains at 3‐km grid spacing. During DA cycles, 3DVar analyses show better fit observations but fastest error growth, while EnKF pure lead smaller forecast...
Abstract Hail forecast evaluations provide important insight into microphysical treatment of rimed ice. In this study we evaluate explicit 0–90-min EnKF-based storm-scale (500-m horizontal grid spacing) hail forecasts for a severe weather event that occurred in Oklahoma on 19 May 2013. Forecast ensembles are run using three different bulk microphysics (MP) schemes: the Milbrandt–Yau double-moment scheme (MY2), triple-moment (MY3), and NSSL variable density-rimed ice (NSSL). Output from...
Abstract This article summarizes research and risk reduction that will inform acquisition decisions regarding NOAA’s future national operational weather radar network. A key alternative being evaluated is polarimetric phased-array (PAR). Research indicates PAR can plausibly achieve fast, adaptive volumetric scanning, with associated benefits for severe-weather warning performance. We assess these using storm observations analyses, observing system simulation experiments, real radar-data...
Abstract The impacts of polarimetric radar data on the estimation uncertain microphysical parameters are investigated through observing system simulation experiments when effects observation operators also considered. Five fundamental (i.e., intercept rain, snow, and hail bulk densities snow hail) estimated individually or collectively using ensemble square root Kalman filter. differential reflectivity ZDR, specific phase KDP, at horizontal polarization ZH used in combinations for parameter...
In this study, the variation of tropical cyclone (TC) rainfall area over subtropical oceans is investigated using Tropical Rainfall Measuring Mission precipitation data collected from 1998 to 2014, with a focus on its relationship environmental conditions. subtropics, higher moving speed and larger vertical wind shear significantly contribute an increase in TC by making horizontal distribution more asymmetric, while sea surface temperature rarely affects fluctuation area. This between...