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.
Education
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Ph D, Atmospheric and Oceanic Sciences
— McGill University (1996) Reflection of solar radiation by inhomogeneous clouds
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Other, Meteorology
— Eotvos Lorand University (1989) The adaptation of a spectral global circulation model
Publications
- Constraining orientation statistics of ice crystals in clouds with observations from deep space. 2026
- Statistics of glinting clouds observed by DSCOVR and geostationary satellites 2026
- Considering the effects of horizontal heterogeneities in satellite-based large-scale statistics of cloud optical properties 2024
- Deep space observations of conditionally averaged global reflectance patterns 2024
- Impact of sun glint off ice clouds on DSCOVR EPIC cloud products 2024
- A new spectrally-invariant approach to the remote sensing of inhomogeneous clouds 2024
- Near-cloud aerosol retrieval using machine learning techniques, and implied direct radiative effects 2022
- Analysis of near-cloud changes in atmospheric aerosols using satellite observations and global model simulations 2021
- A new measurement approach for validating satellite-based above-cloud aerosol optical depth 2021
- Deep space observations of terrestrial glitter 2021
- Deep space observations of cloud glints: Spectral and seasonal dependence 2021
- Deep space observations of sun glints from marine ice clouds 2020
- Developing an aircraft-based angular distribution model of solar reflection from wildfire smoke to aid satellite-based radiative flux estimation 2019
- MISR radiance anomalies induced by stratospheric volcanic aerosols 2018
- Satellite observations of cloud-related variations in aerosol properties 2018
- Scale dependence of cirrus heterogeneity effects. Part II: MODIS NIR and SWIR channels 2018
- EPIC spectral observations of variability in Earth's global reflectance 2018
- Observation-based study on aerosol optical depth and particle size in partly cloudy regions 2017
- Scale dependence of cirrus heterogeneity effects. Part I: MODIS thermal infrared channels 2017
- Terrestrial glint seen from deep space: oriented ice crystals detected from the Lagrangian point 2017
- Testing the two-layer model for correcting near cloud reflectance enhancement using LES/SHDOM simulated radiances 2016
- Radiative characteristics of clouds embedded in smoke derived from airborne multiangular measurements 2016
- Effect of cloud fraction on near-cloud aerosol behavior in the MODIS atmospheric correction ocean color product 2015
- CALIPSO observations of near-cloud aerosol properties as a function of cloud fraction 2014
- Extending 3D near-cloud corrections from shorter to longer wavelengths 2014
- Near-cloud aerosol properties from the 1-km resolution MODIS ocean product 2014
- Improvement of MODIS aerosol retrievals near clouds 2013
- Shape-induced gravitational sorting of Saharan dust during transatlantic voyage: Evidence from CALIOP lidar depolarization measurements 2013
- Multi-satellite aerosol observations in the vicinity of clouds 2013
- CALIPSO observations of transatlantic dust: vertical stratification and effect of clouds 2012
- Cloud droplet size retrievals from zenith radiance measurements: examples from the Atmospheric Radiation Measurement Program and the Aerosol Robotic Network 2012
- Effect of CALIPSO cloud aerosol discrimination (CAD) confidence levels on observations of aerosol properties near clouds 2012
- Taking the pulse of pyrocumulus clouds 2012
- Analysis of co-located MODIS and CALIPSO observations near clouds 2012
- A variational method to retrieve the extinction profile in liquid clouds using multiple field-of-view lidar 2012
- Cloud Impact on Surface Altimetry From a Spaceborne 532-nm Micropulse Photon-Counting Lidar: System Modeling for Cloudy and Clear Atmospheres 2011
- Implementation on Landsat data of a simple cloud mask algorithm developed for MODIS land bands 2011
- Global CALIPSO observations of aerosol changes near clouds 2011
- Influence of cloud retrieval errors due to three dimensional radiative effects on calculations of broadband cloud radiative effect
Courses Taught
- Computational Physics
- Computational Physics