A5038443927- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Meteorological Phenomena and Simulations
- Ionosphere and magnetosphere dynamics
- Precipitation Measurement and Analysis
- Atmospheric aerosols and clouds
- Lepidoptera: Biology and Taxonomy
- Tropical and Extratropical Cyclones Research
- Geology and Paleoclimatology Research
- Soil Moisture and Remote Sensing
- Fossil Insects in Amber
- Oceanographic and Atmospheric Processes
- Parallel Computing and Optimization Techniques
- Calibration and Measurement Techniques
- Spaceflight effects on biology
- Freshwater macroinvertebrate diversity and ecology
- Cryospheric studies and observations
- Distributed and Parallel Computing Systems
- Hydrology and Drought Analysis
- Methane Hydrates and Related Phenomena
- Advanced Computational Techniques and Applications
- Geophysics and Gravity Measurements
- Ocean Waves and Remote Sensing
Texas A&M University
2014-2025
Mitchell Institute
2008-2024
Pennsylvania State University
2015
NOAA Earth System Research Laboratory
2013
Swiss Federal Laboratories for Materials Science and Technology
2013
NILU
2013
NOAA Air Resources Laboratory
2013
University of Utah
2013
Jet Propulsion Laboratory
2013
Forschungszentrum Jülich
2013
Abstract The Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) provides a calibration-based sequential scheme for combining precipitation estimates from multiple satellites, as well gauge analyses where feasible, at fine scales (0.25° × 0.25° and 3 hourly). TMPA is available both after in real time, based on calibration by the TRMM Combined Instrument Microwave Imager products, respectively. Only after-real-time product incorporates data present. dataset...
Abstract. The Total Carbon Column Observing Network (TCCON) produces precise measurements of the column average dry-air mole fractions CO2, CO, CH4, N2O and H2O at a variety sites worldwide. These observations rely on spectroscopic parameters that are not known with sufficient accuracy to compute total columns can be used in combination situ measurements. TCCON must therefore calibrated World Meteorological Organization (WMO) trace gas measurement scales. We present calibration data using...
The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring attributing climate change. CLARREO measurements establish new change benchmarks with high absolute radiometric accuracy statistical confidence across wide range essential variables. CLARREO's inherently be verified traceable on to Système Internationale (SI) units. established by critical assessing changes Earth system model...
Winds derived from analyzed geopotential height fields are used to study quasi‐horizontal mixing by the large‐scale flow in lower stratosphere during austral spring. This is period when Antarctic ozone hole appears and disappears. Trajectories computed for large ensembles of particles initially inside outside main polar vortex. Mixing transport diagnosed through estimates finite time Lyapunov exponents Lagrangian dispersion statistics tracer trajectories. At 450 K above prior vortex...
Water vapor samples collected during tropical field experiments at Puerto Escondido, Mexico, near Kwajalein (KWAJEX), and Key West, Florida (CAMEX 4), were analyzed for their stable isotope contents, 1 H 2 18 O: 16 O O. Highest δ values approached isotopic equilibrium with seawater quiescent weather or in regions of isolated disorganized convection. Lowest occurred downwind from organized mesoscale disturbances ranged as low 15‰ below seawater. The mean value over the sea surface therefore...
Abstract On 27 August 2013, during the Studies of Emissions and Atmospheric Composition, Clouds Climate Coupling by Regional Surveys field mission, NASA's ER‐2 research aircraft encountered a region enhanced water vapor, extending over depth approximately 2 km minimum areal extent 20,000 in stratosphere (375 K to 415 potential temperature), south Great Lakes (42°N, 90°W). Water vapor mixing ratios this plume, measured Harvard Vapor instrument, constitute highest values recorded situ at these...
Abstract This study investigates the spatial characteristics of nonzero rain rates to develop a probability density function (PDF) model precipitation using rainfall data from Tropical Rainfall Measuring Mission (TRMM) satellite. The minimum χ2 method is used find good estimator for rain-rate distribution between gamma and lognormal distributions, which are popularly in simulation PDF. Results sensitive choice dynamic range, but both distributions match well with PDF data. Comparison sample...
Nine years of total ozone measurements from the Total Ozone Mapping Spectrometer (TOMS) on Nimbus 7 are used to study global structure quasi-biennial oscillation (QBO) in ozone. Interannual variability near equator (10°S 10°N) is dominated by QBO. The equatorial anomalies independent season and well correlated (r > 0.8) with zonal wind. In both hemispheres midlatitude two three times larger winter than summer. Global patterns QBO identified computing lagged correlations between zonal-mean...
Abstract Although climate models have steadily improved their ability to reproduce the observed climate, over years there has been little change wide range of sensitivities exhibited by different a doubling atmospheric CO2 concentrations. Stochastic optimization is used mimic how six independent model development efforts might use same general circulation model, set observational constraints, and skill criteria choose settings for parameters thought be important sources uncertainty related...
A global climatology of total column ozone has been computed from 4 years daily observations by the mapping spectrometer aboard Nimbus 7 polar‐orbiting satellite. Observations were made at local noon; no are available in polar regions during night. The orbital data have area averaged onto a regular 5° latitude‐longitude grid. coverage is more than 90% complete last 3 observing (October 1979 to September 1982) and approximately 70% first year 1978 1979). Global maps temporal mean rms variance...
Abstract Four years of precipitation retrievals from the Tropical Rainfall Measuring Mission (TRMM) satellite are compared with data 25 surface rain gauges on National Oceanic and Atmospheric Administration/Pacific Marine Environment Laboratory (NOAA/PMEL) Atmosphere–Ocean Array/Triangle Trans-Ocean Buoy Network TAO/TRITON buoy array in tropical Pacific. The have a significant advantage over island-based for this purpose because they represent open-ocean conditions not affected by island...
The Stratosphere–Troposphere Analyses of Regional Transport 2008 (START08) experiment investigated a number important processes in the extratropical upper troposphere and lower stratosphere (UTLS) using National Science Foundation (NSF)–NCAR Gulfstream V (GV) research aircraft. main objective was to examine chemical structure UTLS relation dynamical spanning range scales. campaign conducted during April–June from Broomfield, Colorado. A total 18 flights sampled an extensive geographical...
During the Stratosphere‐Troposphere Analyses of Regional Transport (START) experiment in December 2005, behavior extratropical tropopause was examined under a variety dynamical conditions. Using situ measurements ozone and water vapor, on board new NSF/NCAR research aircraft Gulfstream V, data from large‐scale meteorological analyses, we address issues definitions sharpness. Comparisons two flights show that sharpness chemical transitions across varies with static stability change...
Abstract Rossby wave breaking is an important mechanism for the two-way exchange of air between tropical upper troposphere and lower stratosphere extratropical stratosphere. The authors present a 30-yr climatology (1981–2010) anticyclonically cyclonically sheared wave-breaking events along boundary tropics in 350–500-K potential temperature range from ECMWF Interim Re-Analysis (ERA-Interim). Lagrangian transport analyses show net equatorward near 380 K poleward at altitudes below above...
In October 2011 an American Geophysical Union Chapman Conference was held in Grindelwald, Switzerland, titled “Advances Lagrangian Modeling of the Atmosphere.” models are being applied to a wide range high-impact atmospheric phenomena, such as transport volcanic ash and dispersion radioactive releases. One common theme that arose during meeting is need for improved access output products forecast reanalysis systems, which used in-puts trajectory models. The steady increases horizontal...
[1] Model simulations with the Chemical Lagrangian Model of Stratosphere (CLaMS) driven by wind fields National Center for Environmental Prediction (NCEP) were performed in midlatitude tropopause region April 2008 to study two research flights conducted during START08 campaign. One flight targeted a deep tropospheric intrusion and another stratospheric event, both them vicinity subtropical polar jet. Air masses strong signatures mixing between air identified from measured CO-O3 correlations,...
Abstract Convection that penetrates the tropopause (overshooting convection) rapidly transports air from lower troposphere to stratosphere, potentially mixing between two layers. This exchange of can have a substantial impact on composition, radiation, and chemistry upper stratosphere (UTLS). In order improve our understanding role convection plays in transport trace gases across tropopause, this study presents 10 year analysis overshooting for eastern thirds contiguous United States March...
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Large numbers of particle trajectories are used to characterize the mean-meridional transport circulation an idealized general model (GCM). The GCM has a uniform land surface, no topography or land–sea contrasts, and seasonal cycle. analyzed using both Lagrangian-mean statistics approach based on Green's function tracer equation. It is shown that distribution provides estimate ensemble-mean for inviscid Lagrangian means have number problems render their interpretation difficult, including...
Accurate determination of the tropopause is important for applications such as dynamical analysis and forecasting, radiative transfer calculations, diagnosis chemical transport in atmosphere. In this paper, we examine how well extratropical determined National Centers Environmental Prediction high‐resolution Global Forecast System (GFS) model over continental United States using aircraft radiosonde data. The GFS analyses sounding data compare well, with RMS differences approximately 600 m,...
Abstract A new method that combines radar reflectivities from individual Next Generation Weather Radars (NEXRAD) into a three-dimensional composite with high horizontal and vertical resolution is used to estimate storm-top altitudes for the continental United States east of Rocky Mountains. Echo-top are compared altitude lapse-rate tropopause calculated ERA-Interim reanalysis radiosondes. To sample diurnal annual cycles, tropopause-penetrating convection analyzed at 3-h intervals throughout...
Abstract Position and intensity data from the International Best Track Archive for Climate Stewardship (IBTrACS) are combined with global, gridded precipitation estimates Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) period 1998–2013 to study diurnal cycle of in tropical cyclones. The comprehensive global coverage large sample size afforded by two datasets allow robust statistical analysis storm-averaged variations permit stratification various ways....
This list consists of 1825 species and varieties Lepidoptera which have been taken in Alberta. Of these, 657 are records captures the hitherto almost completely neglected Microlepidoptera. Though few specialists on this continent studied taxonomy large group, those who done so certain families generously assisted classifying recorded. Unfortunately, a it has impossible to obtain assistance. Despite omissions necessitates, constitutes most comprehensive catalogue Microlepidoptera has, up...
Hourly averaged precipitation rates from an ensemble of the Community Climate Model version 3 (CCM3) simulations for 44‐month period January 1998 through August 2001 are compared to observations Tropical Rainfall Measuring Mission (TRMM) satellite. In order have adequate sampling by satellite, comparisons made 15° longitude × 10° latitude boxes and larger geographical areas within tropics. The temporally spatially hourly CCM3 TRMM fit diurnal harmonic method linear least squares regression,...
Satellite ozone data from the Total Ozone Mapping Spectrometer 1979 through 1986 show that recent decreases of total have not been confined to Antarctic spring season (the hole), but are global in extent. The losses about twice estimated uncertainty satellite data. largest middle and high latitudes occur all seasons year. for this 8-year period comparable magnitude increases observed during 1960s. Southern Hemisphere values generally greater than those 1985.