Tamas Varnai

tamas.varnai@nasa.gov
(301) 614-6408
Curriculum Vitae

Education

  • 1996
Ph.D., Atmospheric and Oceanic Sciences, McGill University, Montreal, Canada
  • 1989
M.Sc. equivalent degree, Meteorology, Eotvos Loránd University, Budapest, Hungary

Research Interests

  • Theory of three-dimensional radiative processes that occur in clouds. This work includes participation in the I3RC project.
  • Use of satellite observations for estimating properties of heterogeneous clouds, including water content and size of cloud droplets. This work involves the analysis of MODIS, MISR and ASTER observations of sunlight reflected from clouds and thermal radiation emitted by clouds.
  • Measurement of geometrical thickness and internal structure of clouds, snow, and sea ice, using the airborne lidar instrument called THOR. This work involves the development of data processing algorithms and the analysis of THOR observations.

Background

  • At UMBC, taught graduate-level courses on solar radiation in the atmosphere (2001, 2003, 2005, 2006).
  • As a postdoctoral research associate at McGill University and at the University of Arizona, developed operational algorithms for MISR to estimate the amount of sunlight clouds reflect (1996-1999).
  • As a teaching assistant for 6 semesters at McGill University,
    taught tutorials for an introductory
    course on meteorology and assisted in a graduate-level course on climate dynamics (1992-1996).
  • As a research meteorologist at the Hungarian Meteorological Service, developed and
    implemented algorithms for the operational processing of meteorological satellite data (1989-1991).

View the complete list of my publications


Latest Publications

Varnai, T., and A. Marshak, 2009: MODIS observations of enhanced clear sky reflectance near clouds. Geophys. Res. Lett., 36, L06807, doi:10.1029/2008GL037089. [Abstract] [Full Text (PDF)]

Yang, Y., A. Marshak, T. Varnai, W. J. Wiscombe, and P. Yang, 2009: Uncertainties in ice sheet altimetry from a space-borne 1064 nm single channel lidar due to undetected thin clouds. IEEE Trans. Geos. Remote Sens. (In press) [Abstract] [Full Text (PDF)]

Evans, K. F., A. Marshak, and T. Varnai, 2008: The potential for improved cloud optical depth retrievals from the multiple directions of MISR. J. Atmos. Sci., 65, 3179-3196. [Abstract] [Full Text (PDF)]

Varnai, T., and A. Marshak, 2007: View angle dependence of cloud optical thickness retrieved by MODIS. J. Geophys. Res., 112, D06203, doi:10.1029/2005JD006912. [Abstract] [Full Text (PDF)]

Varnai, T., and R. F. Cahalan, 2007: Potential for airborne offbeam lidar measurements of snow and sea ice thickness. J. Geophys. Res., 112, C12S90, doi:10.1029/2007JC004091. [Abstract] [Full Text (PDF)]

Marshak, A., S. Platnick, T. Varnai, G. Wen, and R. F. Cahalan, 2006: Impact of 3D radiative effects on satellite retrievals of cloud droplet sizes. J. Geophys. Res., 111, DO9207, doi:10.1029/2005JD006686. [Abstract] [Full Text (PDF)]

Oreopoulos, L., A. Marshak, R. F. Cahalan, T. Varnai, A. B. Davis, and A. Macke, 2006: New Directions in the Radiative Transfer of Cloudy Atmospheres. EOS, 87, No. 5, 31 January 2006. [Full Text (PDF)]

Cahalan, R. F., M. McGill, J. Kolasinski, T. Varnai, and K. Yetzer, 2005: THOR — Cloud Thickness from Offbeam Lidar Returns. J. Atmos. Ocean. Tech., 22, No. 6, 605-627. [Abstract] [Full Text (PDF)]

Cahalan, R. F., L. Oreopoulos, A. Marshak, K. F. Evans, A. Davis, R. Pincus, K. Yetzer, B. Mayer, R. Davies, T. Ackerman, H. Barker, E. Clothiaux, R. Ellingson, M. Garay, E. Kassianov, S. Kinne, A. Macke, W. OHirok, P. Partain, S. Prigarin, A. Rublev, G. Stephens, F. Szczap, E. Takara, T. Varnai, G. Wen, and T. Zhuravleva, 2005: The International Intercomparison of 3D Radiation Codes (I3RC): Bringing together the most advanced radiative transfer tools for cloudy atmospheres. Bull. Amer. Meteor. Soc., 86 (9), 1275-1293. [Abstract] [Full Text (PDF)]

Varnai, T., and A. Marshak, 2003: A method for analyzing how various parts of clouds influence each other's brightness. J. Geophys. Res., 108 (D22), 4706, doi: 10.1029/2003JD003561. [Abstract] [Full Text (PDF)]

View all my Publications

Latest Images of the Week

CALIPSO Observations of Aerosol Changes Near Clouds (Nov 15, 2009)
Cloud brightness changes caused by horizontal radiative interactions (Jun 7, 2009)
Cloud-Free Air is Brighter at Shorter Wavelengths Around Thicker Clouds (Aug 17, 2008)
Enhanced Clear Sky Brightness in the Vicinity of Clouds (Mar 30, 2008)
Halo observations in snow (Dec 16, 2007)
Concept of new lidar measurements of snow and sea ice thickness (Sep 9, 2007)
Correlation between horizonal cloud size and fractional cloud coverage (May 14, 2006)

View all my IOTWs