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Tamas Varnai

Research Associate Professor

Joint Center for Earth Systems Technology
Nasa/Gsfc Location--Off Campus
Phone
301-614-6408
varnai@umbc.edu
Education
Ph D, McGill University (1996)
Other, Eotvos Lorand University (1989)
About

Prior to joining UMBC in 1999, Dr. Varnai worked as researcher at the Hungarian Meteorological Service, and as postdoctoral fellow at McGill University and at the University of Arizona.

Research Interests

Dr. Varnai’s research aims at improving our ability to measure the properties of clouds and atmospheric aerosols from space, and to use satellite data for better understanding the impact of clouds and aerosols on the solar heating of our planet. He is particularly interested in the way the three-dimensional nature of atmospheric radiative processes affects satellite observations, and in understanding the way atmospheric particle populations change in the vicinity of clouds. His work involves analyzing data from satellite instruments such as MODIS or CALIOP and airborne instruments such as THOR or CAR, and combining the data with theoretical simulations of radiative processes.

Contracts, Fellowships, Grants, and Sponsored Research

Varnai, Tamas (Co-Principal) Gatebe, Charles K. (Principal) Gautam, Ritesh (Co-Principal) Ichoku, Charles (Co-Principal) Characterizing the impact of clouds and aerosols heterogeneity on satellite remote sensing and shortwave radiation budget SubContract (Not Funded) Sponsored by NASA

Varnai, Tamas (Co-Principal) Kostinski, Alexander (Principal) Marshak, Alexander (Co-Principal) Deep space observations of Earth as an exoplanet control experiment Grant (Not Funded) Sponsored by NASA/Task 115 funds

Varnai, Tamas (Co-Principal) Marshak, Alexander (Principal) Yang, Weidong (Co-Principal) Use of CALIOP data for understanding cloud-related variations in aerosol properties and aerosol radiative effects Grant (Currently Under Review) Sponsored by NASA

Varnai, Tamas (Co-Principal) Martins, J. Vanderlei (Principal) Marshak, Alexander (Co-Principal) Remer, Lorraine (Co-Principal) Romero-Talamas, Carlos (Co-Principal) The 3D loud scanner CubeSat for Cloud and Aerosol Measurements Grant (Not Funded) Sponsored by NASA

Varnai, Tamas (Principal) Marshak, Alexander (Co-Principal) Levy, Robert (Co-Principal) Wen, Guoyong (Co-Principal) MODIS and VIIRS aerosol properties in partly cloudy regions Grant (Funded) Sponsored by NASA

Varnai, Tamas (Principal) Kostinski, Alexander (Co-Principal) Yang, Weidong (Co-Principal) Yang, Yuekui (Co-Principal) Characterizing ice clouds using EPIC observations of sun glint Grant (Not Funded) Sponsored by NASA

Intellectual Contributions

MISR radiance anomalies induced by stratospheric volcanic aerosols vol. 10 1875 Remote Sensing

Satellite observations of cloud-related variations in aerosol properties vol. 9 doi: 10.3390/atmos9110430 Atmosphere

Scale dependence of cirrus heterogeneity effects. Part II: MODIS NIR and SWIR channels vol. 18 12105–12121 Atmos. Chem. Phys.

EPIC spectral observations of variability in Earth's global reflectance vol. 10 doi:10.3390/rs10020254 Remote Sensing

Observation-based study on aerosol optical depth and particle size in partly cloudy regions vol. 122 doi: 10.1002/2017JD027028 J. Geophys. Res.

Scale dependence of cirrus heterogeneity effects. Part I: MODIS thermal infrared channels vol. 17 8489-8508, doi: 10.5194/acp-17-8489-2017 Atmos. Chem. Phys.

Terrestrial glint seen from deep space: oriented ice crystals detected from the Lagrangian point vol. 44 doi:10.1002/2017GL073248 Geophys. Res. Lett.

Testing the two-layer model for correcting near cloud reflectance enhancement using LES/SHDOM simulated radiances vol. 121 9661–9674 Journal of Geophysical Research

Radiative characteristics of clouds embedded in smoke derived from airborne multiangular measurements vol. 121 doi:10.1002/2016JD025309 J. Geophys. Res.

Effect of cloud fraction on near-cloud aerosol behavior in the MODIS atmospheric correction ocean color product vol. 7 5283-5299 Remote Sensing

CALIPSO observations of near-cloud aerosol properties as a function of cloud fraction vol. 41 9150-9157 Geophys. Res. Lett.

Extending 3D near-cloud corrections from shorter to longer wavelengths vol. 147 79-85 J. Quant. Spect. Radiative Transfer

Near-cloud aerosol properties from the 1-km resolution MODIS ocean product 3 vol. 119 1546–1554 Journal of Geophysical Research

Improvement of MODIS aerosol retrievals near clouds vol. 118 9168–9181 Journal of Geophysical Research

Shape-induced gravitational sorting of Saharan dust during transatlantic voyage: Evidence from CALIOP lidar depolarization measurements 12 vol. 40 3281-3286 Geophysical Research Letters

vol. 13 3899-3908 Atmospheric Chemistry and Physics

CALIPSO observations of transatlantic dust: vertical stratification and effect of clouds vol. 12 11339-11354 Atmospheric Chemistry and Physics

Cloud droplet size retrievals from zenith radiance measurements: examples from the Atmospheric Radiation Measurement Program and the Aerosol Robotic Network vol. 12 10313-10329 Atmospheric Chemistry and Physics

Effect of CALIPSO cloud aerosol discrimination (CAD) confidence levels on observations of aerosol properties near clouds vol. 116 131-141 Atmospheric Research

Taking the pulse of pyrocumulus clouds vol. 52 121-130 Atmospheric Environment

Analysis of co-located MODIS and CALIPSO observations near clouds vol. 5 389-396 Atmospheric Measurement Techniques

A variational method to retrieve the extinction profile in liquid clouds using multiple field-of-view lidar vol. 51 350-365 Journal of applied meteorology and climatology

Cloud Impact on Surface Altimetry From a Spaceborne 532-nm Micropulse Photon-Counting Lidar: System Modeling for Cloudy and Clear Atmospheres vol. 49 4910-4919 IEEE Trans. Geosci. Rem. Sens.

Implementation on Landsat data of a simple cloud mask algorithm developed for MODIS land bands vol. 99 597-601 IEEE Geosc. & Rem. Sens. Lett.

Global CALIPSO observations of aerosol changes near clouds vol. 8 19-23 IEEE Geosci. Remote Sens. Lett.

Presentations

(Author & Presenter) (Author) (Author) (Author) (Author) (Author) AMS 99th Annual Meeting Oral Presentation Satellite observations of cloud-related variations in aerosol properties American Meteorological Society Phoenix, AZ

(Author & Presenter) (Author) (Author) AMS 99th Annual Meeting Oral Presentation Terrestrial glints seen from the Lagrangian point: Clouds vs. oceans American Meteorological Society Phoenix, AZ

(Author & Presenter) (Author) (Author) 2018 AGU Fall Meeting Poster Deep space observations of sun glint over oceanic regions American Geophysical Union Washington, DC

(Author & Presenter) (Author) (Author) 2018 AGU Fall Meeting Oral Presentation Terrestrial glints seen from the Lagrangian point: Clouds vs. oceans American Geophysical Union Washington, DC

(Author & Presenter) (Author) (Author) (Author) (Author) (Author) 2018 AGU Fall Meeting Oral Presentation Aerosol properties in partly cloudy regions American Geophysical Union Washington, DC

(Author & Presenter) (Author) (Author) (Author) (Author) 2018 MODIS-VIIRS Science Team Meeting Oral Presentation Aerosol properties in partly cloudy regions NASA Silver Spring, MD

(Author & Presenter) (Author) (Author) (Author) (Author) NASA GSFC Climate and Radiation Lab Seminar Series Oral Presentation Characterizing ice clouds using EPIC observations of sun glint NASA Greenbelt, MD

(Author & Presenter) (Author) (Author) 2018 DSCOVR Science Team Meeting Oral Presentation Characterizing ice clouds using EPIC observations of sun glint NASA Greenbelt, MD

(Author & Presenter) (Author) (Author) 15th Conference on Atmospheric Radiation Oral Presentation Deep space observations of sun glint from oceans and from oriented ice crystals American Meteorological Society Vancouver, Canada

(Author & Presenter) (Author) (Author) (Author) 15th Conference on Atmospheric Radiation Oral Presentation Earth's global reflectance spectral variability as observed by DSCOVR/EPIC Amerocan Meteorological Society Vancouver, Canada

(Author & Presenter) (Author) (Author) (Author) EGU General Assembly 2018 Oral Presentation Spectral variability in Earth's global reflectance as observed by DSCOVR/EPIC European Geosciences Union Vienna, Austria

(Author & Presenter) (Author) (Author) 2018 Sun-Climate Symposium Oral Presentation Long-term variations in Terra/MISR angular radiance differences: Solar or aerosol influences on polar cloudiness? NASA Lake Arrowhead, CA

(Author & Presenter) (Author) Deep Space Gateway Workshop Oral Presentation Specular reflection of sunlight from Earth NASA Denver, CO

(Author & Presenter) (Author) (Author) AGU 2017 Fall Meeting Oral Presentation Deep space detection of oriented ice crystals American Geophysical Union New Orleans

(Author & Presenter) (Author) (Author) AGU 2017 Fall Meeting Poster Automatic detection of glints from ice clouds in DSCOVR observations American Geophysical Union New Orleans, LA

(Author & Presenter) (Author) (Author) (Author) AGU 2017 Fall Meeting Poster EPIC observations of the Earth’s global mean reflectance American Geophysical Union New Orleans, LA

(Author & Presenter) (Author) (Author) 2017 DSCOVR Science Team Meeting Oral Presentation Deep space observations of oriented ice crystals NASA NASA GSFC, Greenbelt, MD

(Author & Presenter) (Author) (Author) 2017 DSCOVR Science Team Meeting Oral Presentation EPIC spectral observations on the global mean and variability of Earth’s reflectance NASA NASA GSFC, Greenbelt, MD

(Author & Presenter) (Author) (Author) (Author) (Author) CERES Science Team Meeting Oral Presentation Aerosol properties in a cloudy world NASA NASA GSFC, Greenbelt, MD

(Author & Presenter) (Author) (Author) CERES Science Team Meeting Oral Presentation Deep space observations of oriented ice crystals NASA NASA GSFC, Greenbelt, MD

(Author & Presenter) (Author) (Author) (Author) (Author) (Author) 2017 Joint Assembly Oral Presentation Variations in the Earth color and brightness as observed by DSCOVR/EPIC IUGG, IAPSO, IAMAS, IAGA Cape town, South Africa

(Author & Presenter) (Author) (Author) Climate and Radiation Laboratory meeting Oral Presentation Terrestrial glint from deep space Code 613, NASA GSFC Greenbelt, MD

(Author & Presenter) (Author) (Author) (Author) (Author) ICAP 2017: International Cooperative for Aerosol Prediction, 9th Technical Working Group Meeting: Radiative Transfer and Impacts of aerosol radiative forcing on Numerical Weather Prediction Oral Presentation Radiative transfer: From plane parallel to 3D Lille, France

(Author & Presenter) (Author) (Author) Clouds, their Properties, and their Climate Feedbacks: what have we learned in the satellite era? Oral Presentation Deep space observations of oriented ice crystals NASA New York City, NY

(Author & Presenter) (Author) (Author) A-Train Symposium 2017 Oral Presentation Aerosol properties in partly cloudy conditions NASA Pasadena, CA

(Author & Presenter) (Author) (Author) 16th Electromagnetic and Light Scattering Conference Oral Presentation Specular reflection from oriented ice crystals observed from deep space College Park, MD

(Author & Presenter) (Author) (Author) (Author) 2016 AGU Fall Meeting Oral Presentation Radiative characteristics of clouds embedded in and occurring beneath smoke using airborne multiangular measurements American Geophysical Union San Francisco, CA

(Author & Presenter) (Author) (Author) (Author) (Author) 2016 AGU Fall Meeting Oral Presentation Characterizing the solar reflection from wildfire smoke plumes using airborne multiangle measurements American Geohysical Union San Francisco, CA

(Author & Presenter) (Author) (Author) 2016 AGU Fall Meeting Poster Specular reflection from nearly horizontal ice crystals in EPIC data American Geophysical Union San Francisco, CA

(Author) (Author & Presenter) (Author) 2016 AGU Fall Meeting Poster Variations in Earth brightness observed by EPIC American Geophysical Union San Francisco

(Author & Presenter) (Author) (Author) (Author) (Author) (Author) Scientific Meeting to Honor Gyorgy Major Oral Presentation Satellite measurements of atmospheric aerosols in the vicinity of clouds Hungarian Academy of Sciences & Hungarian Meteorological Service Budapest, Hungary

(Author & Presenter) (Author) (Author) Yoram Kaufman Memorial Symposium Oral Presentation Aerosol properties in partly cloudy conditions NASA GSFC Greenbelt, MD

2016 MODIS/VIIRS Science Team Meeting Poster Application of an improved correction algorithm to MODIS aerosol retrievals NASA Silver Spring, MD

2016 MODIS/VIIRS Science Team Meeting Oral Presentation MODIS and CALIPSO observations of aerosol properties in partly cloudy conditions NASA Silver Spring, MD

(Author) (Author & Presenter) (Author) (Author) (Author) 2016 International Radiation Symposium Oral Presentation Testing the two-layer model for estimating cloud-induced clear sky reflectance enhancement using LES/SHDOM computed radiances International Radiation Commission Auckland, New Zealand

(Author & Presenter) (Author) (Author) 2016 International Radiation Symposium Oral Presentation Cloud-related variations in aerosol properties observed by MODIS International Radiation Commission Auckland, New Zealand

(Author & Presenter) (Author) (Author) 2016 International Radiation Symposium Oral Presentation Theory and possible applications of the spectrally invariant approximation International Radiation Commission Auckland, New Zealand

(Author & Presenter) (Author) (Author) CALIPSO-CloudSat Science Team Meeting Oral Presentation Effect of cloud fraction on near-cloud aerosol behaviors NASA Newport News, VA

(Author & Presenter) (Author) (Author) CALIPSO-CloudSat Science Team Meeting Poster Some technical aspects of a CALIOP and MODIS data analysis that examines near-cloud aerosol properties as a function of cloud fraction NASA Newport News, VA

(Author & Presenter) (Author) (Author) (Author) (Author) 2015 AGU Fall Meeting Oral Presentation Radiative interactions of clouds embedded in wildfire smoke using multiangular airborne observations American Geophysical Union San Francisco, CA

(Author & Presenter) (Author) (Author) (Author) 2015 AGU Fall Meeting Poster Effect of wildfires on surface reflectance from a savanna ecosystem American Geophysical Union San Francisco, CA

(Author & Presenter) (Author) (Author) (Author) 2015 AGU Fall Meeting Oral Presentation Impact of cloud and blowing snow on ice sheet altimetry: A comparison between ICESat and ICESat-2 American Geophysical Union San Francisco, CA

(Author) (Author) (Author & Presenter) (Author) (Author) 2015 AGU Fall Meeting Poster An empirical function for bidirectional reflectance characterization for smoke aerosols using multi-angular airborne measurements American Geophysical Union San Francisco, CA

(Author & Presenter) (Author) (Author) (Author) 2015 AGU Fall Meeting Oral Presentation CALIPSO observations of changes in dust properties during transatlantic transport American Geophysical Union San Francisco, CA