Stephen Joseph Munchak

Stephen Joseph Munchak

  • RESEARCH AST, METEOROLOGICAL STUDIES
  • 301.286.2392
  • NASA/GSFC
  • Mail Code: 612
  • Greenbelt , MD 20771
  • Employer: NASA
  • Brief Bio

    Dr. S. Joseph Munchak is a Research Meteorologist at NASA Goddard Space Flight Center (GSFC), Greenbelt, Maryland. Dr. Munchak completed a B. S. and M. S. in Meteorology at the Pennsylvania State University in 2006 and Ph. D. in Atmospheric Science at Colorado State University in 2010. He was a Research Associate and Assistant Research Scientist at the University of Maryland, College Park's Earth System Science Interdisciplinary Center from 2010 until 2015, when we took his current position at NASA GSFC. Dr. Munchak's main research interests are in the integration of passive and active microwave measurements to improve retrievals of clouds and precipitation. This work has many avenues which Dr. Munchak has engaged in current and past research investigations, including development of three-dimensional inversion methods, optimal parameterizations of rain and snow particle size distributions, development of clear-air retrievals for precipitation detection, and surface characterization for active and passive sensors. Dr. Munchak is currently a PI on the NASA Precipitation Measurement Missions Science Team and serves as an Associate Editor for Atmospheric Measurement Techniques.

    Research Interests

    Precipitation Remote Sensing

    How can we make more precise quantitative estimates of precipitation from space? The primary instrumentation we use to investigate precipitation measures passively and actively (radar) in the microwave region of the electromagnetic spectrum. Thus, to answer this question, we need to understand the microwave scattering characteristics of precipitation particles of all types (rain, snow, graupel, etc), sizes, and shapes. I work with radiative transfer models that simulate these measurements to develop retrieval methods and inform the design of new instruments to improve our knowledge in this area. 

    Microwave Land Surface Characterization

    The land surface emissivity and reflectivity are important boundary conditions for understanding data from passive and active microwave measurements of falling precipitation. They also contain some information about previously fallen precipitation. My interest in this area is thus to better understand these relationships to improve instantaneous and cumulative precipitation estimates.

    Publications

    Refereed

    Munchak, S. J., R. Meneghini, M. Grecu, and W. S. Olson. 2016. "A Consistent Treatment of Microwave Emissivity and Radar Backscatter for Retrieval of Precipitation over Water Surfaces." Journal of Atmospheric and Oceanic Technology, 33 (2): 215-229 [10.1175/jtech-d-15-0069.1]

    Matsui, T., W.-K. Tao, S. J. Munchak, M. Grecu, and G. J. Huffman. 2015. "Satellite view of quasi-equilibrium states in tropical convection and precipitation microphysics." Geophysical Research Letters, 42 (6): 1959–1968 [10.1002/2015GL063261]

    Williams, C. R., V. N. Bringi, L. D. Carey, et al. V. Chandrasekar, P. N. Gatlin, Z. S. Haddad, R. Meneghini, S. Joseph Munchak, S. W. Nesbitt, W. A. Petersen, S. Tanelli, A. Tokay, A. Wilson, and D. B. Wolff. 2015. "Reply to “Comments on ‘Describing the Shape of Raindrop Size Distributions Using Uncorrelated Raindrop Mass Spectrum Parameters’”." Journal of Applied Meteorology and Climatology, 54 (9): 1977-1982 [10.1175/jamc-d-15-0058.1]

    Williams, C., V. N. Bringi, L. D. Carey, et al. V. Chandresakar, P. N. Gatlin, Z. S. Haddad, R. Meneghini, S. J. Munchak, S. W. Nesbitt, W. A. Petersen, S. Tanelli, A. Tokay, A. Wilson, and D. B. Wolff. 2014. "Describing the Shape of Raindrop Size Distributions Using Uncorrelated Raindrop Mass Spectrum Parameters." Journal of Applied Meteorology and Climatology, 53 (5): 1282-1296 [10.1175/JAMC-D-13-076.1]

    Munchak, S., and G. Skofronick-Jackson. 2013. "Evaluation of precipitation detection over various surfaces from passive microwave imagers and sounders." Atmospheric Research, 131: 81-94 [10.1016/j.atmosres.2012.10.011]

    Skofronick-Jackson, G., B. Johnson, and S. Munchak. 2013. "Detection Thresholds of Falling Snow From Satellite-Borne Active and Passive Sensors." IEEE Trans. Geosci. Remote Sensing, 51 (7): 4177-4189 [10.1109/TGRS.2012.2227763]

    Bringi, V., G. Huang, S. J. Munchak, et al. C. Kummerow, D. A. Marks, and D. B. Wolff. 2012. "Comparison of Drop Size Distribution Parameter ( D 0 ) and Rain Rate from S-Band Dual-Polarized Ground Radar, TRMM Precipitation Radar (PR), and Combined PR–TMI: Two Events from Kwajalein Atoll." J of Atmos and Oceanic Tech, 29 (11): 1603-1616 [10.1175/JTECH-D-11-00153.1]

    Munchak, S., C. Kummerow, and G. Elsaesser. 2012. "Relationships between the Raindrop Size Distribution and Properties of the Environment and Clouds Inferred from TRMM." J. Climate, 25 (8): 2963-2978 [10.1175/JCLI-D-11-00274.1]

    Munchak, S. J., and D. Christian. 2011. "A Modular Optimal Estimation Method for Combined Radar–Radiometer Precipitation Profiling." J. Appl. Meteor. Climatol., 50 (2): 433–448 [10.1175/2010JAMC2535.1]

    Munchak, S., and A. Tokay. 2008. "Retrieval of Raindrop Size Distribution from Simulated Dual-Frequency Radar Measurements." J. Appl. Meteor. Clim., 47 (1): 223-239 [10.1175/2007JAMC1524.1]

    Brief Bio

    Dr. S. Joseph Munchak is a Research Meteorologist at NASA Goddard Space Flight Center (GSFC), Greenbelt, Maryland. Dr. Munchak completed a B. S. and M. S. in Meteorology at the Pennsylvania State University in 2006 and Ph. D. in Atmospheric Science at Colorado State University in 2010. He was a Research Associate and Assistant Research Scientist at the University of Maryland, College Park's Earth System Science Interdisciplinary Center from 2010 until 2015, when we took his current position at NASA GSFC. Dr. Munchak's main research interests are in the integration of passive and active microwave measurements to improve retrievals of clouds and precipitation. This work has many avenues which Dr. Munchak has engaged in current and past research investigations, including development of three-dimensional inversion methods, optimal parameterizations of rain and snow particle size distributions, development of clear-air retrievals for precipitation detection, and surface characterization for active and passive sensors. Dr. Munchak is currently a PI on the NASA Precipitation Measurement Missions Science Team and serves as an Associate Editor for Atmospheric Measurement Techniques.

    Publications

    Refereed

    Munchak, S. J., R. Meneghini, M. Grecu, and W. S. Olson. 2016. "A Consistent Treatment of Microwave Emissivity and Radar Backscatter for Retrieval of Precipitation over Water Surfaces." Journal of Atmospheric and Oceanic Technology 33 (2): 215-229 [10.1175/jtech-d-15-0069.1]

    Matsui, T., W.-K. Tao, S. J. Munchak, M. Grecu, and G. J. Huffman. 2015. "Satellite view of quasi-equilibrium states in tropical convection and precipitation microphysics." Geophysical Research Letters 42 (6): 1959–1968 [10.1002/2015GL063261]

    Williams, C. R., V. N. Bringi, L. D. Carey, et al. V. Chandrasekar, P. N. Gatlin, Z. S. Haddad, R. Meneghini, S. Joseph Munchak, S. W. Nesbitt, W. A. Petersen, S. Tanelli, A. Tokay, A. Wilson, and D. B. Wolff. 2015. "Reply to “Comments on ‘Describing the Shape of Raindrop Size Distributions Using Uncorrelated Raindrop Mass Spectrum Parameters’”." Journal of Applied Meteorology and Climatology 54 (9): 1977-1982 [10.1175/jamc-d-15-0058.1]

    Williams, C., V. N. Bringi, L. D. Carey, et al. V. Chandresakar, P. N. Gatlin, Z. S. Haddad, R. Meneghini, S. J. Munchak, S. W. Nesbitt, W. A. Petersen, S. Tanelli, A. Tokay, A. Wilson, and D. B. Wolff. 2014. "Describing the Shape of Raindrop Size Distributions Using Uncorrelated Raindrop Mass Spectrum Parameters." Journal of Applied Meteorology and Climatology 53 (5): 1282-1296 [10.1175/JAMC-D-13-076.1]

    Munchak, S., and G. Skofronick-Jackson. 2013. "Evaluation of precipitation detection over various surfaces from passive microwave imagers and sounders." Atmospheric Research 131 81-94 [10.1016/j.atmosres.2012.10.011]

    Skofronick-Jackson, G., B. Johnson, and S. Munchak. 2013. "Detection Thresholds of Falling Snow From Satellite-Borne Active and Passive Sensors." IEEE Trans. Geosci. Remote Sensing 51 (7): 4177-4189 [10.1109/TGRS.2012.2227763]

    Bringi, V., G. Huang, S. J. Munchak, et al. C. Kummerow, D. A. Marks, and D. B. Wolff. 2012. "Comparison of Drop Size Distribution Parameter ( D 0 ) and Rain Rate from S-Band Dual-Polarized Ground Radar, TRMM Precipitation Radar (PR), and Combined PR–TMI: Two Events from Kwajalein Atoll." J of Atmos and Oceanic Tech 29 (11): 1603-1616 [10.1175/JTECH-D-11-00153.1]

    Munchak, S., C. Kummerow, and G. Elsaesser. 2012. "Relationships between the Raindrop Size Distribution and Properties of the Environment and Clouds Inferred from TRMM." J. Climate 25 (8): 2963-2978 [10.1175/JCLI-D-11-00274.1]

    Munchak, S. J., and D. Christian. 2011. "A Modular Optimal Estimation Method for Combined Radar–Radiometer Precipitation Profiling." J. Appl. Meteor. Climatol. 50 (2): 433–448 [10.1175/2010JAMC2535.1]

    Munchak, S., and A. Tokay. 2008. "Retrieval of Raindrop Size Distribution from Simulated Dual-Frequency Radar Measurements." J. Appl. Meteor. Clim. 47 (1): 223-239 [10.1175/2007JAMC1524.1]

                                                                                                                                                                                            
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