A5022894247- Meteorological Phenomena and Simulations
- Climate variability and models
- Tropical and Extratropical Cyclones Research
- Precipitation Measurement and Analysis
- Atmospheric aerosols and clouds
- Geophysics and Gravity Measurements
- Atmospheric chemistry and aerosols
- Fire effects on ecosystems
- Cryospheric studies and observations
- Ionosphere and magnetosphere dynamics
- Solar Radiation and Photovoltaics
- Remote Sensing in Agriculture
- Geography and Environmental Studies
- Lightning and Electromagnetic Phenomena
- Atmospheric Ozone and Climate
- Water Quality and Resources Studies
- Ocean Waves and Remote Sensing
- Spacecraft and Cryogenic Technologies
- Oceanographic and Atmospheric Processes
- Climate change impacts on agriculture
- Coastal and Marine Dynamics
- Digital Marketing and Social Media
- Environmental and biological studies
- Technology Adoption and User Behaviour
- Hydrology and Watershed Management Studies
East Carolina University
2011-2021
Cooperative Institute for Mesoscale Meteorological Studies
2019
University of Oklahoma
2019
San Jose State University
2006-2008
University of Maryland, Baltimore County
1999-2004
Systems Technology (United States)
2002
Goddard Space Flight Center
1998-2002
Colorado State University
1998
National Academies of Sciences, Engineering, and Medicine
1998
Massachusetts Institute of Technology
1992
It has long been known that trade wind cumulus and deep cumulonimbus represent primary components of the broad spectrum clouds in Tropics, which led to concept a bimodal distribution tropical clouds. However, recent analyses shipboard radar data from Tropical Ocean Global Atmosphere Coupled Ocean‐Atmosphere Response Experiment (COARE) provide evidence abundant populations third cloud type, congestus. Congestus constitute over half precipitating convective COARE contribute one-quarter total...
Four distinct meteorological regimes in the Amazon basin have been examined to distinguish contributions from boundary layer aerosol and convective available potential energy (CAPE) continental cloud structure electrification. The lack of distinction electrical parameters (peak flash rate, lightning yield per unit rainfall) between aerosol‐rich October aerosol‐poor November premonsoon regime casts doubt on a primary role for enhancing Evidence substantial suppressing warm rain coalescence is...
Radar and electrical measurements for deep tropical convection are examined both “break period” “monsoonal” regimes in the vicinity of Darwin, Australia. Break period consists primarily continental convection, whereas oceanic-based dominates during monsoonal periods, associated with monsoon trough over Darwin. Order-of-magnitude enhancements lightning flash rates regime 10–20-dB radar reflectivity mixed-phase region compared regime. The latter differences attributed to effect convective...
The occurrence frequency and rainfall production of mesoscale convective systems (MCSs) relative to smaller groups clouds over the tropical oceans is not well known. Eighty days shipboard radar data collected during recent Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) were used provide a detailed view convection in western Pacific warm pool, region global climatological significance. aim this study was document occurrence, production, depth...
Regimes of lower tropospheric northwesterly wind observed in southwestern Amazônia during the Tropical Rainfall Measuring Mission Large‐Scale Biosphere Atmosphere (TRMM‐LBA) field campaign were shown to be local manifestations stationary frontal systems that extended into deep Tropics along South Atlantic Convergence Zone (“SACZ” regime). Frontal transient and confined subtropics interim periods easterly weak westerly flow (“non‐SACZ” Observations from surface‐based radar TRMM‐LBA suggested...
Abstract Vertical structures of 2-day waves and the Madden–Julian oscillation (MJO) are projected onto vertical normal modes for a quiescent tropical troposphere. Three capture gross tropospheric structure waves, while only two needed to represent most baroclinic MJO. Deep circulations that project first mode associated with deep cumulonimbus stratiform rainfall. Shallow higher wavenumber precipitating shallow cumulus congestus For both disturbances horizontal divergence contributed by is an...
This paper examines the origins of a secondary nocturnal maximum in cloudiness and precipitation southwestern Amazonia, diurnal feature observed previously by many investigators. Analysis is based on satellite, radar, sounding, profiler observations precipitating systems from Tropical Rainfall Measuring Mission Large-Scale Biosphere–Atmosphere (TRMM-LBA) coincident Wet-Season Atmospheric Mesoscale Campaign (WETAMC) field programs during early 1999 wet season. The general finding that...
In this paper, data collected from 51 days of continual upper-atmospheric soundings and the Tropical Ocean Global Atmosphere (TOGA) radar at Anglo–Brazilian Amazonian Climate Observation Study (ABRACOS) Hill during Rainfall Measuring Mission component Brazilian Large Scale Biosphere–Atmosphere (TRMM-LBA) experiment are used to describe mean thermodynamic kinematic airmass properties wet season convection over Rondonia, Brazil. Distinct multiday easterly westerly lower-tropospheric wind...
A comparison of the submonthly variability atmospheric circulation and organization convection in South America during January–February–March 1998 (JFM98) 1999 (JFM99) is presented. According to National Centers for Environmental Prediction reanalysis, American low-level jet (SALLJ) was about twice as strong JFM El Niño episode than La Niña episode. The difference SALLJ strength between these two years translated into stronger transport moist tropical air subtropics JFM98 JFM99. An objective...
Abstract The evolution of monsoon onset across South America has complex temporal and regional variability that are controlled by local remote land–ocean–atmosphere processes. In this study, a three‐stage conceptual model for the American season is proposed based on rain threshold analysis rotated empirical orthogonal function (REOF) Global Precipitation Climatology Project version 2 (GPCP‐v2) dataset. This two‐pronged approach allowed identification regions share common seasonal cycle...
Abstract The onset of the South American monsoon season culminates with abrupt establishment convergence zone (SACZ). impact cold fronts on SACZ is studied using an 11‐year composite analysis dynamic and thermodynamic structures, intensity propagation that occur prior to, during, after in SACZ. A significant change structure observed at time SACZ, suddenly stalling becoming stationary southeastern Brazil. It proposed this regime causes mechanism for sudden front behaviour suggested by...
Abstract Millions of people in the United States regularly acquire information from weather forecasts for a wide variety reasons. The rapid growth mobile device technology has created convenient means to retrieve this data, and recent years, applications (MWAs) have quickly gained popularity. Research on sources, however, been unable sufficiently capture importance form gathering. As use these apps continues grow, it is important gain insight usefulness MWAs consumers. To better examine MWA...
Surface radar observations near Niamey, Niger, during the African Monsoon Multidisciplinary Analyses (AMMA) campaign in 2006 documented structure, motion, and precipitation of cloud systems monsoon season. These unique for that part Sahel were combined with satellite rain estimates infrared imagery to study diurnal cycle rainfall Niger. This confirms bimodal structure Niamey AMMA, seen by previous studies West rainfall. Radar analysis squall line mesoscale convective (SLMCS) non‐MCS isolated...
Abstract The seasonal and interannual variability of the structure, evolution, propagation midlatitude cyclones in southeast United States are studied using a composite analysis. In upper levels, composites show that axis wintertime upper-level trough remains north–south oriented propagates eastward along 40°N, while summertime has much slower at farther north latitude an is tilted northeast–southwest direction. Upper-level circulation changes consistent with shift from “cyclonic behavior”...
This article describes results from a new four‐year (2009–2012) radar‐based precipitation climatology for the southeastern United States (SE USA). The shows that size‐based classification between mesoscale features (MPF) and isolated reveals distinct seasonal diurnal variability of precipitation. On average, 70 to 90% is associated with MPF, generally less in summertime southern coastal regions. MPF has relatively small cycle except Florida warm offshore waters Gulf Stream. In contrast,...
Abstract Two features of Yanai et al.’s profiles Q1 and Q2—the commonly observed double-peak structure to Q2 an inflection in the profile below melting level—are explored using estimates convective stratiform rainfall partitioning based on Massachusetts Institute Technology (MIT) radar reflectivity data collected during TOGA COARE. The MIT allow be classified according rain fraction within domain and, limitations datasets, interpretations made about relative contributions precipitation mean...
Abstract In this study, a 10-yr (1998–2007) climatology of observations from the Tropical Rainfall Measuring Mission (TRMM) satellite is used to study regional mechanisms monsoon onset across tropical and subtropical South America. The approach contrast differences in structure, intensity, rainfall mesoscale convective systems (MCSs) prior after onset, context thermodynamic conditions National Centers for Environmental Prediction (NCEP) reanalysis data. This accomplished by analyzing mean...
Precipitation estimation over the tropical oceans is commonly performed using passive infrared (IR) measurements of cloud-top brightness temperature from geostationary satellites to infer location deep convection. It has been recognized in recent years that majority precipitation produced by mesoscale convective systems (MCSs). However, relationship between IR patterns associated with MCSs and underlying not well understood. The assumption coldest cloud tops are deep, active convection...
One of the important goals NASA’s Cirrus Regional Study Tropical Anvils and Layers–Florida Area Experiment (CRYSTAL-FACE) was to further understanding evolution tropical anvil clouds generated by deep convective systems. An step toward radiative properties convectively is study their life cycle. Observations from ground-based radar, geostationary satellite radiometers, aircraft, radiosondes during CRYSTAL-FACE provided a comprehensive look at generation systems over South Florida July 2002....
An active day during the Coupled Ocean–Atmosphere Response Experiment (COARE) Intensive Observation Period (IOP) is examined in which nine convective systems evolved and moved eastward across region of shipboard radar coverage Flux Array (IFA) within westerly wind burst conditions. The detailed genesis, morphology, interactions between these cloud are documented from a satellite perspective. One was large complex elliptical cluster, among largest observed Tropical Ocean Global Atmosphere...
Abstract This study analyzes the effect of location North Atlantic Subtropical High (NASH) western ridge on daily variability precipitation organization in southeastern United States (SE US). The side NASH, also known as NASH ridge, plays an important role summertime this region. In study, mean position was determined and used to classify each summer day during 2009–2012 into one four quadrants. Composites synoptic‐scale circulation from mesoscale isolated features (MPF IPF) were calculated...
Abstract A radar-based analysis of the structure, motion, and rainfall variability westward-propagating squall-line mesoscale convective systems (SLMCSs) in Niamey, Niger, during African Monsoon Multidisciplinary Activities (AMMA) 2006 special observing period is combined with an 700-mb (hPa) winds relative vorticity to study relationship between SLMCSs easterly waves (AEWs). Radar results show that were most important rainmakers Niamey accounted for about 90% despite being present less than...
Abstract Isolated precipitating convection, though a minor contributor to total rainfall in the tropics, is important regional and seasonal climate variability because its diabatic heating structure characteristic of convectively inactive phase tropical interseasonal oscillations. This study extends previous analysis mesoscale convective system (MCS) South America monsoon examine differences annual cycle vertical isolated convection over 10 year period 1998–2007. The goal document variation...
The sea-breeze (SB) is an important source of summertime precipitation in North Carolina (NC, southeast United States). However, not all SB events produce precipitation. A climatology wet and dry NC used to investigate the conditions that are conducive associated with sea breeze. Radar imagery was detect 88 occurred along coast between May-September 2009-2012. majority (85%) during offshore flow (53%) or parallel (22%). were separated into (47%) differences dynamic thermodynamic parameters...