A5091160852- Meteorological Phenomena and Simulations
- Climate variability and models
- Ocean Waves and Remote Sensing
- Tropical and Extratropical Cyclones Research
- Wind and Air Flow Studies
- Oceanographic and Atmospheric Processes
- Atmospheric aerosols and clouds
- Aeolian processes and effects
- Fluid Dynamics and Turbulent Flows
- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Coastal and Marine Dynamics
- Precipitation Measurement and Analysis
- Geophysics and Gravity Measurements
- Cryospheric studies and observations
- Atmospheric chemistry and aerosols
- Radio Wave Propagation Studies
- Computational Fluid Dynamics and Aerodynamics
- Methane Hydrates and Related Phenomena
- Solar and Space Plasma Dynamics
- Seismic Imaging and Inversion Techniques
- Seismic Waves and Analysis
- Gas Dynamics and Kinetic Theory
- earthquake and tectonic studies
- Catalytic Processes in Materials Science
United States Naval Research Laboratory
2014-2024
Naval Research Laboratory Marine Meteorology Division
2022
Anhui Provincial Meteorological Bureau
2014
University Corporation for Atmospheric Research
2003-2010
California State University, Monterey Bay
2007-2010
Neurobehavioral Research Laboratory and Clinic
2005-2010
Yale University
2000-2008
Grace (United States)
2004
Abstract Flow in a stably stratified environment is characterized by anisotropic and intermittent turbulence wavelike motions of varying amplitudes periods. Understanding intermittency wave‐turbulence interactions flow remains challenging issue geosciences including planetary atmospheres oceans. The stable atmospheric boundary layer (SABL) commonly occurs when the ground surface cooled longwave radiation emission such as at night over land surfaces, or even daytime snow ice warm air advected...
Uniformly stratified moist flow over a Gaussian-shaped circular mountain is investigated using anonhydrostatic mesoscale model. The focus the interaction between stagnation and orographicprecipitation. Two closely related issues are addressed: effect of condensation precipitation onmountain stagnation, influence blocking latent heat on upslope precipitation. Itis demonstrated that release can significantly delay onset mountainflow stagnation. dynamical thermodynamical nature this...
Abstract During austral winter, and away from orographic maxima or “hot spots,” stratospheric gravity waves in both satellite observations Interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-Interim) data reveal enhanced amplitudes a broad midlatitude belt extending across the Southern Ocean east of Andes to south New Zealand. The peak latitude this feature slowly migrates poleward 50° 60°S. Wave are much weaker Pacific Ocean. These features wave field...
Abstract A case of orographic precipitation in the Alps on 20 September 1999 was studied using several models, along with rain‐gauge and radar data. The objective study is to describe transformation an air mass, including multi‐scale aspects. Several new some conventional diagnostic quantities are estimated, drying ratio, efficiency, buoyancy work, condensed‐water residence time, parcel changes heat, moisture altitude, dominant space‐ time‐scales. For considered, ratio about 35%....
Abstract Orographic precipitation is studied by analyzing the sensitivity of numerical simulations to variations in mountain height, width, and wind speed. The emphasis on upslope lifting over isolated mountains cold climates. An attempt made capture essential steady-state volume-averaged cloud physics a pair coupled nonlinear algebraic equations. To do this, single-pathway snow formation models are analyzed with both linear accretion formulations. model suggests that efficiency determined...
Abstract A large-amplitude mountain wave generated by strong southwesterly flow over southern Greenland was observed during the Fronts and Atlantic Storm-Track Experiment (FASTEX) on 29 January 1997 NOAA G-IV research aircraft. Dropwindsondes deployed every 50 km flight level data depict a vertically propagating with deep convectively unstable layers, potential temperature perturbations of 25 K that deformed tropopause lower stratosphere, vertical velocity maximum nearly 10 m s−1 in...
Abstract Using the National Science Foundation (NSF)–NCAR Gulfstream V and NSF–Wyoming King Air research aircraft during Terrain-Induced Rotor Experiment (T-REX) in March–April 2006, six cases of Sierra Nevada mountain waves were surveyed with 126 cross-mountain legs. The goal was to identify influence tropopause on entering stratosphere. During each flight leg, part variation observed parameters due parameter layering, heaving up down waves. Diagnosis combined wave-layering signal aided...
Numerical simulations of flow over steep terrain using 11 different nonhydrostatic numerical models are compared and analyzed. A basic benchmark five other test cases simulated in a two-dimensional framework the same initial state, which is based on conditions during Intensive Observation Period (IOP) 6 Terrain-Induced Rotor Experiment (T-REX), intense mountain-wave activity was observed. All use an identical horizontal resolution 1 km vertical resolution. The six various heights: 100-m...
Uniformly stratified moist flow over a Gaussian-shaped circular mountain is investigated using anonhydrostatic mesoscale model. The focus the interaction between stagnation and orographicprecipitation. Two closely related issues are addressed: effect of condensation precipitation onmountain stagnation, influence blocking latent heat on upslope precipitation. Itis demonstrated that release can significantly delay onset mountainflow stagnation. dynamical thermodynamical nature this...
Abstract Two mistral events observed in 1999 during the Mesoscale Alpine Programme (MAP) are studied using observational data and high‐resolution mesoscale‐model simulations from US Navy's Coupled Ocean Atmosphere Prediction System (COAMPS). Radiosondes suggested that both wind were associated with passage of cold fronts post‐frontal air descent. EuroSat Rapidscan images indicated a stationary persistent cloud edge along lee Massif Central. The marks beginning flow acceleration descent...
Abstract The absorption of trapped lee waves by the atmospheric boundary layer (BL) is investigated based on numerical simulations and theoretical formulations. It demonstrated that amplitude decays exponentially with downstream distance due to BL absorption. decay coefficient, α, defined as inverse e-folding distance, found be sensitive both surface momentum heat fluxes. Specifically, α larger over a rougher surface, associated more turbulent BL. On other hand, value decreases increasing...
Abstract High-resolution observations from scanning Doppler and aerosol lidars, wind profiler radars, as well surface aircraft measurements during the Terrain-induced Rotor Experiment (T-REX) provide first comprehensive documentation of small-scale intense vortices associated with atmospheric rotors that form in lee mountainous terrain. Although are already recognized potential hazards for aircraft, it is proposed these vortices, or subrotors, most dangerous features because strong shear...
Abstract The impact of fast-propagating swell on the air–sea momentum exchange and marine boundary layer is examined based multiple large-eddy simulations over a range wind speed parameters in light-wind–fast-wave regime. A wave-driven supergeostrophic jet forms near top wave when forwarding-pointing (i.e., negative) form drag associated with fast wind-following overpowers positive surface shear stress. magnitude increases wavelength slope decreases increasing speed, intensity general drag....
Abstract A detailed analysis is undertaken of the primary Alpine shear zone that occurred on 1 October 1999 during Mesoscale Programme. This emanates from south‐western tip in north‐westerly flow conditions, develops response to Alpine‐scale splitting, and separates northerly mistral wind south‐west Alps quasi‐stagnant air within wake. The study based situ flight‐level dropsonde data two research aircraft. are used for construction an objective a cross‐section perpendicular zone, diagnostic...
Abstract A one-layer model of the atmospheric boundary layer (BL) is proposed to explain nature lee-wave attenuation and gravity wave absorption seen in numerical simulations. Two complex coefficients are defined: compliance coefficient reflection coefficient. real-valued ratio reflected incident energy also useful. The key result that, due horizontal friction, wind response BL shifted upstream compared phase disturbances free atmosphere. associated flow divergence modulates thickness so...
The characteristics of gravity waves excited by the complex terrain central Alps during intensive observational period (IOP) 8 Mesoscale Alpine Programme (MAP) is studied through analysis aircraft in situ measurements, GPS dropsondes, radiosondes, airborne lidar data, and numerical simulations. Mountain wave breaking occurred over on 21 October 1999, associated with wind shear, turning, a critical level Richardson number less than unity just above flight (∼5.7 km) research NCAR Electra....
Three research aircraft observed small-amplitude gravity waves over the south-western French Alps on 13 November 1999 during Mesoscale Alpine Programme (MAP). Radiosonde ascents and Global Positioning System dropsondes deployed by MAP indicate that upstream flow was characterized topographic blocking below 2 km low-level directional wind shear associated with a synoptic-scale depression extended above crest. The in situ vertical velocity data from three aircraft, backscatter lidar onboard...
Abstract The two‐month special observing period of the Mesoscale Alpine Programme (MAP) in autumn 1999 included a variety complex mountain wave events. Seven events were carefully analyzed, compared with numerical models and described published papers. These detailed investigations revealed some common dynamical elements, i.e. importance low‐level processes involving slow‐moving boundary layer, wind shear causing either absorption or decoupling/spilling, upstream blocking, latent heat...
Abstract. This paper presents an evaluation and validation of the Naval Research Laboratory's COAMPS® real-time forecasts during VOCALS-REx over area off west coast Chile/Peru in Southeast Pacific October November 2008. The analyses focus on marine boundary layer (MBL) structure. These are compared with lower troposphere soundings, situ surface measurements, satellite observations. predicted mean MBL cloud wind spatial distributions good agreement large-scale longitudinal variation structure...
An observational and modeling study of a bora event that occurred during the field phase Mesoscale Alpine Programme is presented. Research aircraft in‐situ measurements airborne remote‐sensing observations indicate presence strong low‐level wave breaking alternating surface wakes jets along Croatian coastline over Adriatic Sea. The observed features are well captured by high‐resolution COAMPS simulation. Analysis results long‐extending above boundary layer induced dissipation associated with...
The impact of diurnal forcing on a downslope wind event that occurred in Owens Valley California during the Sierra Rotors Project (SRP) spring 2004 has been examined based observational analysis and diagnosis numerical simulations. observations indicate while upstream flow was characterized by persistent westerlies at above mountaintop level cross-valley winds exhibited strong variation. simulations using Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) capture many observed...
Abstract Measurements from the National Science Foundation/National Center for Atmospheric Research (NSF/NCAR) Gulfstream V (G-V) obtained during recent Terrain-Induced Rotor Experiment (T-REX) indicate marked differences in character of wave response between repeated flight tracks across Sierra Nevada, which were separated by a distance approximately 50 km. Observations several G-V research flights that vertical velocities primary exhibited variations up to factor 2 southern and northern...