A5080503586- Meteorological Phenomena and Simulations
- Climate variability and models
- Atmospheric aerosols and clouds
- Atmospheric and Environmental Gas Dynamics
- Precipitation Measurement and Analysis
- Geophysics and Gravity Measurements
- Ocean Waves and Remote Sensing
- Plant Ecology and Soil Science
- Ecology and Conservation Studies
- Tropical and Extratropical Cyclones Research
- Wind and Air Flow Studies
- Ionosphere and magnetosphere dynamics
- Spectroscopy and Laser Applications
- Plant Water Relations and Carbon Dynamics
- Solar and Space Plasma Dynamics
- Atmospheric chemistry and aerosols
- GNSS positioning and interference
- Fluid Dynamics and Turbulent Flows
- Laser Design and Applications
- Oceanographic and Atmospheric Processes
- Lightning and Electromagnetic Phenomena
- Air Quality Monitoring and Forecasting
- Atmospheric Ozone and Climate
- Aerodynamics and Fluid Dynamics Research
- Radar Systems and Signal Processing
NSF National Center for Atmospheric Research
2016-2025
U.S. National Science Foundation
2025
Earth Observing Laboratory
2008-2020
University of Manitoba
2019
University of Oklahoma
2008-2019
Research Manitoba
2019
Microscale (United States)
2019
Mesoscale & Microscale Meteorology Laboratory
2019
Research Applications (United States)
2019
Iowa State University
2019
[1] Recent progress is reviewed in the understanding of convective interaction with water vapor and changes associated warmer climates. Progress includes new observing techniques (including isotopic methods) that are helping to illuminate moisture-convection interaction, better observed humidity trends, modeling approaches, clearer expectations as hydrological consequences increased specific a climate. A theory appears be place predict free troposphere if winds known at large scales,...
The International H2O Project (IHOP_2002) is one of the largest North American meteorological field experiments in history. From 13 May to 25 June 2002, over 250 researchers and technical staff from United States, Germany, France, Canada converged on Southern Great Plains measure water vapor other atmospheric variables. principal objective IHOP_2002 obtain an improved characterization time-varying three-dimensional evaluate its utility improving understanding prediction convective processes....
Abstract The central Great Plains region in North America has a nocturnal maximum warm-season precipitation. Much of this precipitation comes from organized mesoscale convective systems (MCSs). This is counterintuitive the sense that activity over out phase with local generation CAPE by solar heating surface. lower troposphere environment typically characterized low-level jet (LLJ) just above stable boundary layer (SBL), and available potential energy (CAPE) values peak SBL, resulting...
Abstract Within the framework of international field campaign COPS (Convective and Orographically‐induced Precipitation Study), a large suite state‐of‐the‐art meteorological instrumentation was operated, partially combined for first time. This includes networks in situ remote‐sensing systems such as Global Positioning System well synergy multi‐wavelength passive active instruments advanced radar lidar systems. The phase performed from 01 June to 31 August 2007 low‐mountain area southwestern...
Boundary layer clear-air echoes are routinely observed with sensitive, microwave, Doppler radars similar to the WSR-88D. Operational and research meteorologists using these velocities derive winds. The accuracy of winds derived from depends on nature scatterers. This paper uses dual-wavelength dual-polarization examine cause use return estimate origin has been an ongoing controversy in radar meteorology. These have attributed refractive-index gradient (Bragg scattering) insects birds...
The Autonomous Modular Scanner, onboard the Ikhana remotely operated aircraft, captured fires over Basin Fire Complex in Monterey County, California, on 8 July 2008.The image has been overlaid onto terrain data within Google Earth to provide additional information fire managers effects of behavior.The yellow areas depict active areas, with reds and purples showing burned-over areas.
Data from the Convection and Precipitation/Electrification (CaPE) project, as well results numerical simulations, are used to study horizontal convective rolls. The environmental conditions necessary for sustaining rolls influencing aspect ratio, ratio of roll wavelength boundary layer (CBL) depth, orientation examined. Observations model simulations both suggest that a moderate surface sensible heat flux some vertical wind shear existence. Unlike previous studies, however, it is shown...
Spaceborne radar interferometric delay measurements were used to infer high-resolution maps of integrated atmospheric water vapor, which can be readily related meteorological phenomena. Maps the vapor distribution associated with a precipitating cloud, partly cold front, and horizontal convective rolls reveal quantitative measures that are not observed conventional methods, suggest such observations for forecasting study dynamics.
Abstract Data from the Convection and Precipitation/Electrification (CaPE) Experiment conducted during summer of 1991 are used to examine quantify horizontal variability temperature moisture within convective boundary layer (CBL). Potential variations were only about 0.5 K, while in water vapor mixing ratio values 1.5–2.5 g kg−1 observed throughout CBL. Using radar, aircraft, sounding data, it is shown that rolls likely cause these variabilities. The enhanced occurred roll updraft regions,...
Abstract Forecast errors with respect to wind, temperature, moisture, clouds, and precipitation largely correspond the limited capability of current Earth system models capture simulate land–atmosphere feedback. To facilitate its realistic simulation in next-generation models, an improved process understanding related complex interactions is essential. this end, accurate 3D observations key variables (L–A) high vertical temporal resolution from surface free troposphere are indispensable....
Observations during the Convection and Precipitation/Electrification (CaPE) project illustrate that horizontal convective rolls are capable of providing sufficient forcing to initiate free moist convection. Rolls occurred on majority days CaPE but only some those were they able trigger thunderstorms. This study was undertaken ascertain difference between two types roll days: storm no-storm days. All obvious sounding parameters examined: stability parameters, midlevel moisture, vertical wind...
A comprehensive observational dataset encompassing the entire temporal evolution of horizontal convective rolls was obtained for first time. Florida, Illinois, and Kansas measurements from preroll conditions through development well-defined to their dissipation were utilized determine factors influencing roll evolution. When buoyancy flux reached a critical value 35–50 W m−2, form boundary layer convection resolved by radar rolls. It noted that two-dimensional can evolve in absence...
The three-dimensional kinematic structures of offshore and onshore flow sea-breeze fronts observed during the CaPE experiment are shown using high resolution dual-Doppler aircraft data. interact with horizontal convective rolls (HCRs) that develop within boundary layer. Nearly perpendicular intersections between HCRs front were case. Close to front, HCR axes tilted upward lifted by frontal updrafts. Consequently, a deeper updraft was created at intersection points, providing additional...
Precipitating convection in a mountain region of moderate topography is investigated, with particular emphasis on its initiation response to boundary-layer and mid-and upper-tropospheric forcing mechanisms.The data used the study are from COPS (Convective Orographically-induced Precipitation Study) that took place southwestern Germany eastern France summer 2007.It found precipitating can be roughly classified as being due either: (i) surface heating low-level flow convergence; (ii) moisture...
Abstract A water vapor micropulse differential absorption lidar (DIAL) instrument was developed collaboratively by the National Center for Atmospheric Research (NCAR) and Montana State University (MSU). This innovative, eye-safe, low-power, diode-laser-based system has demonstrated ability to obtain unattended continuous observations in both day night. Data comparisons with well-established observing systems, including radiosondes, Emitted Radiance Interferometers (AERIs), microwave...
On 13 July 1986 a cold-air outflow from thunderstorms over Illinois and Missouri propagated through the MIST (Microburst Severe Thunderstorm) network northern Alabama. The study of this is important since gust front was solely responsible for initiation numerous convective cells. Previous studies have documented convection due to colliding fronts. In addition, there pronounced mesoscale organization cells atop boundary. This most likely combination Kelvin–Helmholtz (K–H) internal gravity...
Abstract The evolution of a mesoscale convective system (MCS) observed during the International H2O Project that took place on Great Plains United States is described. MCS formed at night in frontal zone, with four initiation episodes occurring between approximately 0000 and 0400 local time. Radar, radiosonde, surface data together show least three were elevated, from moist conditionally unstable layers located above boundary layer, which had been stabilized by previous MCSs. Initiation...
Abstract A climatology of convection initiation (CI) and convective enhancements (CE) has been developed using radar reflectivity data in southwestern Germany eastern France over the period May–August 2000–2006 2008. The study region included Vosges Mountains France, Rhine Valley which straddles Germany, Black Forest Swabian Germany. Convection occurred frequently during summer months throughout region. CI density (number initiations per square km) illustrates preferential formation mountain...
Abstract A case study of orographic convection initiation (CI) that occurred along the eastern slopes Vosges Mountains in France on 6 August 2007 during Convective and Orographically-Induced Precipitation Study (COPS) is presented. Global positioning system (GPS) receivers two Doppler Wheels (DOW) mobile radars sampled preconvective storm environments were respectively used to retrieve three-dimensional tomographic water vapor wind fields. These retrieved data supplemented with temperature,...
Abstract This study will validate the S-band dual-polarization Doppler radar (S-Pol) refractivity retrieval using measurements from International H2O Project conducted in southern Great Plains May–June 2002. The range of during this project extended out to 40–60 km radar. Comparisons between field and fixed mobile mesonet values within S-Pol domain show a strong correlation. low-flying aircraft also high correlations. Thus, provides good representation low-level atmospheric refractivity....
Abstract Doppler‐On‐Wheels radar observations made during the Convective and Orographically‐induced Precipitation Study (COPS) on 12 August 2007 showed that precipitating clouds only developed between north–south orientated Murg Nagold Valleys of northern Black Forest. The produced moderate precipitation. Weather Research Forecasting (WRF) model run at 700 m horizontal resolution in inner domain was able to simulate location Insight is therefore gained into physical mechanisms responsible...
The southeast Queensland ( SEQ ) region of Australia is recognised for frequent thunderstorms documented through numerous studies including high‐impact severe thunderstorm cases which have caused insured losses exceeding $1 billion AUD . Despite a modest body scientific literature, basic questions regarding the role climate, synoptic and local‐scale (<10 km) processes affecting variability still remain. In an effort to advance these as part Coastal Convective Interactions Experiment CCIE...
Abstract Nocturnal convection initiation (NCI) is more difficult to anticipate and forecast than daytime (CI). A major component of the Plains Elevated Convection at Night (PECAN) field campaign in U.S. Great was intensively sample NCI its near environment. In this article, we summarize types observed during PECAN: 1 June–16 July 2015. These types, classified using PECAN radar composites, are associated with 1) frontal overrunning, 2) low-level jet (LLJ), 3) a preexisting mesoscale...
Abstract Lake Victoria is the largest freshwater lake in Africa, with around 30 million people living on its coastline, and it serves as one of natural resources for East African communities due to prosperous fishing industry. However, 1,000 fishermen die annually severe weather-related accidents. Radar-based research from “HIGH impact Weather lAke sYstem” (HIGHWAY) project 2019 confirmed marked diurnal cycle Victoria, studied over decades, where organized, intense convective systems pose a...