A5043685312- Meteorological Phenomena and Simulations
- Precipitation Measurement and Analysis
- Atmospheric aerosols and clouds
- Climate variability and models
- Soil Moisture and Remote Sensing
- Cryospheric studies and observations
- Tropical and Extratropical Cyclones Research
- Wind and Air Flow Studies
- Ocean Waves and Remote Sensing
- Icing and De-icing Technologies
- Aeolian processes and effects
- Plant Water Relations and Carbon Dynamics
- Atmospheric chemistry and aerosols
- Lightning and Electromagnetic Phenomena
- Ionosphere and magnetosphere dynamics
- Geophysics and Gravity Measurements
- Fire effects on ecosystems
- Earthquake Detection and Analysis
- Atmospheric and Environmental Gas Dynamics
- Arctic and Antarctic ice dynamics
- Seismic Waves and Analysis
- Fluid Dynamics and Turbulent Flows
- Hydrology and Watershed Management Studies
- Radio Wave Propagation Studies
- Remote Sensing and LiDAR Applications
Pennsylvania State University
2015-2024
Council of Science Editors
2022
Columbia University
2022
Cooperative Institute for Mesoscale Meteorological Studies
2008-2021
University of Oklahoma
2008-2021
NOAA National Severe Storms Laboratory
2008-2021
NOAA Atlantic Oceanographic and Meteorological Laboratories
2021
NOAA National Weather Service
2020
Stony Brook University
2020
State University of New York
2020
In the atmosphere, microphysics refers to microscale processes that affect cloud and precipitation particles is a key linkage among various components of Earth's atmospheric water energy cycles. The representation microphysical in models continues pose major challenge leading uncertainty numerical weather forecasts climate simulations. this paper, problem treating divided into two parts: (i) how represent population particles, given impossibility simulating all individually within cloud,...
Abstract Data from polarimetric radars offer remarkable insight into the microphysics of convective storms. Numerous tornadic and nontornadic supercell thunderstorms have been observed by research Weather Surveillance Radar-1988 Doppler (WSR-88D) in Norman, Oklahoma (KOUN); additional storm data come Enterprise Electronics Corporation “Sidpol” C-band radar Enterprise, Alabama, as well King City Ontario, Canada. A number distinctive signatures are repeatedly found each these The forward-flank...
The United States Weather Surveillance Radar-1988 Doppler (WSR-88D) radar network has been upgraded to dual-polarization capabilities, providing operational and research meteorologists with a wealth of new information regarding the types distributions hydrometeors within precipitating storms, as well means for improved data quality.In addition conventional moments reflectivity factor at horizontal polarization (Z H ), velocity (V r spectrum width (W), variables available from radars are...
Abstract Polarimetric radar observations of deep convective storms frequently reveal columnar enhancements differential reflectivity Z DR . Such “ columns” can extend upward more than 3 km above the environmental 0°C level, indicative supercooled liquid drops being lofted by updraft. Previous observational and modeling studies columns are reviewed. To address remaining questions, Hebrew University Cloud Model, an advanced spectral bin microphysical model, is coupled with a polarimetric...
Abstract A novel methodology is introduced for processing and presenting polarimetric data collected by weather surveillance radars. It involves azimuthal averaging of radar reflectivity Z , differential DR cross-correlation coefficient ρ hv phase Φ DP at high antenna elevation, resulting quasi-vertical profiles (QVPs) in a height-versus-time format. Multiple examples QVPs retrieved from the S-, C-, X-band dual-polarization radars elevations ranging 6.4° to 28° illustrate advantages QVP...
Abstract Differential sedimentation of precipitation occurs because heavier hydrometeors fall faster than lighter ones. Updrafts and vertical wind shear can maintain this otherwise transient size sorting, resulting in prolonged regions ongoing particle sorting storms. This study quantifies the impact on S-band polarimetric radar variables (radar reflectivity factor at horizontal polarization ZH, differential ZDR, specific phase KDP, copolar cross-correlation coefficient ρhv). These are...
Abstract Polarimetric radar observations above the melting layer in winter storms reveal enhanced differential reflectivity Z DR and specific phase shift K DP , collocated with reduced copolar correlation coefficient ρ hv ; these signatures often appear as isolated “pockets.” High-resolution RHIs vertical profiles of polarimetric variables were analyzed for a storm that occurred Oklahoma on 27 January 2009, observed Weather Surveillance Radar-1988 Doppler (WSR-88D) Norman. The maximum...
Abstract Spectral (bin) microphysics models are used to simulate polarimetric radar variables in melting hail. Most computations performed a framework of steady-state, one-dimensional column model. Vertical profiles reflectivity factor Z , differential DR specific phase K DP attenuation A h and modeled at S, C, X bands for variety size distributions ice particles aloft. The impact temperature lapse rate, humidity, vertical air velocities, particle density on the is also investigated....
Abstract The processes leading to the development of hail and distribution these events worldwide are reviewed. Microphysical physical characteristics described provide context notable gaps in our understanding what drives grow large, or determines how it falls ground. Distributional explored, utilizing both surface observations hailstones remotely sensed observational data sets identify opportunities needs for new observations. These deficiencies contribute limited capacity forecast its...
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...
In this second part of the series, an overview applications polarimetric radar observations is given.This includes a summary improvements to data quality, and interpretation signatures output algorithms for made in warm-and cold-season precipitation.Examples operational products include hydrometeor classification, hail detection sizing, quantitative precipitation estimation.Signatures reviewed those found severe convective storms supercells such as differential reflectivity (Z DR ) columns,...
Abstract Severe hailstorms produce over $1 billion in insured losses annually the United States, yet details of a given storm’s hail threat (e.g., maximum hailstone size and total hailfall) remain challenging to forecast. Previous research suggests that, addition updraft speed, storm-relative airflow could be equally important for formation growth. This study is first step toward determining how changes environmental wind shear subsequent simulated supercell storm structure affect Using...
Abstract The impact of the collisional warm-rain microphysical processes on polarimetric radar variables is quantified using a coupled microphysics–electromagnetic scattering model. A one-dimensional bin-microphysical rain shaft model that resolves explicitly evolution drop size distribution (DSD) under influence coalescence and breakup, settling, aerodynamic breakup with electromagnetic calculations simulate vertical profiles variables: reflectivity factor at horizontal polarization ZH,...
Abstract The results of theoretical modeling in Part I are utilized to develop practical recommendations for developing the algorithms hail detection and determination its size as well attenuation correction rainfall estimation presence hail. A new algorithm discrimination between small (with maximal less than 2.5 cm), large diameters 5.0 giant with exceeding cm is proposed implemented applications S-band dual-polarization Weather Surveillance Radar-1988 Doppler (WSR-88D) systems....
Abstract Observations and recent high-resolution numerical model simulations indicate that liquid water partially frozen hydrometeors can be lofted considerably above the environmental 0°C level in updrafts of convective storms owing to warm thermal perturbation from latent heating within updraft noninstantaneous nature drop freezing. Consequently, upward extensions positive differential reflectivity (i.e., Z DR ≥ 1 dB)—called columns—may a useful proxy for detecting initiation new examining...
Abstract On the basis of simulations and observations made with polarimetric radars operating at X, C, S bands, backscatter differential phase δ has been explored; identified as an important variable that should not be ignored in precipitation estimations are based on specific K DP , especially shorter radar wavelengths. Moreover, bears information about dominant size raindrops wet snowflakes melting layer. New methods for estimating rain layer suggested. The method is a modified version...
Abstract This article provides an overview of the experimental design, execution, education and public outreach, data collection, initial scientific results from Remote Sensing Electrification, Lightning, Mesoscale/Microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign. RELAMPAGO was a major campaign conducted in Córdoba Mendoza provinces Argentina western Rio Grande do Sul State Brazil 2018–19 that involved more than 200 scientists students United States,...
Abstract The Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS) is a NASA-sponsored field campaign to study wintertime snowstorms focusing on East Coast cyclones. This large cooperative effort takes place during the winters 2020–23 precipitation variability in winter cyclones improve remote sensing numerical forecasts snowfall. Snowfall within these storms frequently organized banded structures multiple scales. causes occurrence evolution wide...
Abstract The scientific community has expressed interest in the potential of phased array radars (PARs) to observe atmosphere with finer spatial and temporal scales. Although convergence occurred between meteorological engineering communities, need exists increase access PAR meteorologists. Here, we facilitate these interdisciplinary efforts field ground-based PARs for atmospheric studies. We cover high-level technical concepts terminology as applied studies atmosphere. A historical...
Abstract High-resolution X-band polarimetric radar data were collected in 19 snowstorms over northern Colorado early 2013 as part of the Front Range Orographic Storms (FROST) project. In each case, small, vertically erect convective turrets observed near echo top. These “generating cells” are similar to those reported literature and characterized by ~1-km horizontal vertical dimensions, velocities 1–2 m s −1 , lifetimes at least 10 min. some cases, these generating cells enshrouded enhanced...
Abstract The authors present observations of the microphysical characteristics deep convection that overshoots altitude extratropical tropopause from analysis polarimetric radar variables reflectivity factor at horizontal polarization ZH, differential ZDR, and specific phase KDP. Identified overshooting convective storms are separated by their organization intensity into three classifications: organized convection, discrete ordinary supercell convection. Composite identified for each...
Abstract Soon, the National Weather Service’s Surveillance Radar-1988 Doppler (WSR-88D) network will be upgraded to allow dual-polarization capabilities. Therefore, it is imperative understand and identify microphysical processes using polarimetric variables. Though melting size sorting of hydrometeors have been investigated, there has relatively little focus devoted impacts evaporation on characteristics rainfall. In this study, a simple explicit bin microphysics one-dimensional rainshaft...
Abstract Polarimetric radar observations of convective storms routinely reveal positive differential reflectivity ZDR extending above the 0°C level, indicative presence supercooled liquid particles lofted by storm’s updraft. The summit such “ZDR columns” is marked a zone enhanced linear depolarization ratio LDR or decreased copolar cross-correlation coefficient ρhv and sharp decrease in that together mark particle freezing zone. To better understand relation between changes storm updraft...
With the new data collected with polarimetric radars comes a set of quality issues and artifacts.It is important for these artifacts to be recognized understood as such, thereby allowing operational meteorologists focus on interpretation physically observations.In this third part series, found in radar are described explained.These include attenuation differential attenuation, nonuniform beam filling, depolarization streaks, three-body scattering signatures.Examples each given, along...
The recent Weather Surveillance Radar-1988 Doppler (WSR-88D) network upgrade to dual-polarization capabilities allows for bulk characterization of microphysical processes in northeastern U.S. winter storms the first time. In this study, quasi-vertical profile (QVP) technique (wherein data from a given elevation angle scan are azimuthally averaged and range coordinate is converted height) extended applied polarimetric WSR-88D observations six Northeast survey their evolving, vertical...