A5017658795- Meteorological Phenomena and Simulations
- Wind and Air Flow Studies
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Plant Water Relations and Carbon Dynamics
- Aeolian processes and effects
- Aerospace and Aviation Technology
- Cryospheric studies and observations
- Air Traffic Management and Optimization
- Remote Sensing and LiDAR Applications
- Vehicle emissions and performance
- Air Quality Monitoring and Forecasting
- Tropical and Extratropical Cyclones Research
- Air Quality and Health Impacts
- Geology and Paleoclimatology Research
- Tree-ring climate responses
- Aerodynamics and Fluid Dynamics Research
- Geophysics and Gravity Measurements
- Tree Root and Stability Studies
- Ecology and Vegetation Dynamics Studies
- Landslides and related hazards
- Climate change and permafrost
- Urban Heat Island Mitigation
University of Virginia
2016-2025
University of South Carolina
2021-2024
Northern Illinois University
2021-2024
University of Nebraska–Lincoln
2021-2024
NSF National Center for Atmospheric Research
2006-2024
University of Colorado Boulder
2009-2024
Texas A&M University
2021-2024
University of Missouri
2024
Cooperative Institute for Research in Environmental Sciences
2024
NOAA Chemical Sciences Laboratory
2024
Abstract. A reliable and precise in situ CO2 CO analysis system has been developed deployed at eight sites the NOAA Earth System Research Laboratory's (ESRL) Global Greenhouse Gas Reference Network. The network uses very tall (> 300 m) television radio transmitter towers that provide a convenient platform for mid-boundary-layer trace-gas sampling. Each analyzer three sample inlets profile sampling, complete vertical is obtained every 15 min. instrument suite one site augmented with cavity...
The exchange of heat, momentum, and mass in the atmosphere over mountainous terrain is controlled by synoptic-scale dynamics, thermally driven mesoscale circulations, turbulence. This article reviews key challenges relevant to understanding processes mountain boundary layer outlines possible research priorities for future. review describes limitations experimental study turbulent complex terrain, impact slope valley breezes on structure convective layer, role intermittent mixing...
Abstract Unmanned aerial vehicles are increasingly used to study atmospheric structure and dynamics. While much emphasis has been on the development of fixed-wing unmanned aircraft for investigations, use multirotor is relatively unexplored, especially capturing winds. The purpose this article demonstrate efficacy estimating wind speed direction with 1) a direct approach using sonic anemometer mounted top hexacopter 2) an indirect attitude data from quadcopter. collected by hovering 10 m...
The Terrain-Induced Rotor Experiment (T-REX) is a coordinated international project, composed of an observational field campaign and research program, focused on the investigation atmospheric rotors closely related phenomena in complex terrain. T-REX took place during March April 2006 lee southern Sierra Nevada eastern California. Atmospheric have been traditionally defined as quasi-two-dimensional vortices that form parallel to downwind mountain ridge under conditions conducive generation...
Abstract Aim Climatic conditions exert a strong control on the geographic distribution of many woodland‐to‐grassland transition zones (or ‘tree lines’). Because woody plants have, in general, weaker cold tolerance than herbaceous vegetation, their altitudinal or latitudinal limits are strongly controlled by sensitivity. While temperature controls dynamics woodland–grassland ecotones relatively well established, ability to modify microclimate and create habitat for seedling establishment...
Abstract Emerging application areas such as air pollution in megacities, wind energy, urban security, and operation of unmanned aerial vehicles have intensified scientific societal interest mountain meteorology. To address needs help improve the prediction weather, U.S. Department Defense has funded a research effort—the Mountain Terrain Atmospheric Modeling Observations (MATERHORN) Program—that draws expertise multidisciplinary, multi-institutional, multinational group researchers. The...
Mountainous terrain exerts an important influence on the Earth's atmosphere and affects atmospheric transport mixing at a wide range of temporal spatial scales. The vertical scale this is determined by height boundary layer, which therefore parameter in air pollution studies, weather forecasting, climate modeling, many other applications. It recognized that spatio-temporal structure daytime convective layer (CBL) strongly modified more complex hilly mountainous compared to flat terrain....
This paper presents a comparison of three model-based algorithms to estimate the wind vector from quadrotor motion, based on increasingly refined models. The vehicle motion models are kinematic particle model, dynamic and rigid-body model. These were characterized using results wind-tunnel experiments flight tests. frequency response characteristics each model then examined determine range fluctuations captured with Analysis shows that bandwidth wind-sensing algorithm increases fidelity...
Abstract. Net vertical air mass export by thermally driven f\\/lows from the atmospheric boundary layer (ABL) to free troposphere (FT) above deep Alpine valleys was investigated. The of pollutants mountainous terrain is presently poorly represented in global chemistry transport models (GCTMs) and needs be quantified. Air budgets were calculated using aircraft observations obtained valleys. results show that on average 3 times valley exported vertically per day under fair weather conditions....
A boundary layer field experiment in the Mexico City basin during period 24 February–22 March 1997 is described. total of six sites were instrumented. At four sites, 915-MHz radar wind profilers deployed and radiosondes released five times per day. Two these also had sodars collocated with profilers. Radiosondes twice day at a fifth site to south basin, rawinsondes flown from another location northeast city three Mixed layers grew depths 2500–3500 m, rapid growth beginning shortly before...
Changes in vegetation cover are known for their ability to modify the surface energy balance and near‐surface microclimate conditions. A major change composition that has been occurring many dryland regions around world is associated with replacement of arid grasslands by desert shrublands. The impact shrub encroachment on regional climate conditions remains poorly investigated, and, date, it unclear how this shift plant community may affect microclimate. Here we used concurrent...
We present a model-based approach to wind velocity profiling using motion perturbations of multirotor unmanned aircraft system (UAS) in both hovering and steady ascending flight. A state estimation framework was adapted set closed-loop rigid body models identified for an off-the-shelf quadrotor. The quadrotor used were characterized flight conditions ranging between 0 2 m/s. obtained identification algorithms determine model structures estimate parameters. measurement method validated...
Abstract In this essay, we highlight some challenges the atmospheric community is facing concerning adequate treatment of flows over mountains and their implications for numerical weather prediction (NWP), climate simulations, impact modeling. With recent increases in computing power (and hence model resolution) models start to face new limitations (such as instability steep terrain). At same time there a growing need sufficiently reliable NWP output drive various (for hydrology, air...
During a special observing period (SOP) of the Mesoscale Alpine Programme (MAP), boundary layer processes in highly complex topography were investigated Riviera Valley southern Switzerland. The main focus was on turbulence structure and turbulent exchange near valley surfaces free troposphere. Due to anticipated spatial inhomogeneity, number different probes deployed cross section through valley. Together with suite more conventional instrumentation, observe mean meteorological valley, this...
This paper reviews the benefits of a better understanding atmospheric exchange processes over mountains. These affect weather and climate variables that are important in meteorological applications related to many scientific disciplines sectors economy. We focus this review on examples hydrology, ecology, agriculture, urban planning, wind energy, transportation, air pollution, change. demonstrate more accurate knowledge mountains, including snow redistribution, microclimate, land-cover...
Abstract The planetary boundary layer (PBL) height is an essential parameter required for many applications, including weather forecasting and dispersion modeling air quality. Estimates of PBL are not easily available often come from twice-daily rawinsonde observations at airports, typically 0000 1200 UTC. Questions arise regarding the applicability heights retrieved these to surrounding locations. Obtaining this information requires knowledge spatial variability heights. This particularly...
Understanding wind conditions is critical for the NASA Advanced Air Mobility (AAM) mission. The types of aircraft, and region atmosphere they operate in, make them highly susceptible to effects. We demonstrate feasibility using lidar measure dynamics AAM Wind vector measurements from two Doppler lidars dual-Doppler techniques are compared with in situ a ground-based sonic anemometer small uninhabited aircraft systems (sUAS). Both beams intersected directly above were compared. resulting root...
In the lee of Santa Ynez Mountains north Barbara, CA, late afternoon-to-early morning episodes offshore, northerly gusty downslope surface winds are frequently observed. These locally known as Sundowners. Sundowners spatially non-uniform and can be accompanied by rapid increases in temperature decreases relative humidity with significant impact on fire behavior. Our understanding spatial temporal variability underlying mesoscale mechanisms is limited. To address this knowledge gap,...
The atmospheric boundary layer above forest canopies is difficult to measure in practice, and our understanding of its flow physics, including the potential wind resource, limited part by observational constraints. Most available datasets come from tower point measurements, which do not generally reach into heights encountered a turbine rotor, or remote sensing are usually located outside clearing thus accurately represent conditions canopy. Here, we present field campaign that deployed four...
Mountain ranges have important influences on the structure and composition of convective boundary layer (CBL) free troposphere (FT). Evolution summer CBL, measured over European Alps using airborne lidar, was clearly observed to attain a near‐uniform height up 4.2 km asl by early afternoon. A climatology in‐situ high‐alpine aerosol measurements suggests that such substantial growth, corresponding ∼ 0.3 mid‐latitude tropopause height, often occurs during months. Subsequent nocturnal collapse...