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Pavlos Kollias

Atmospheric Scientist - Joint Appointment

Kollias is a Professor at the School of Marine and Atmospheric Sciences at Stony Brook University – State University of New York and has a joint appointment with the Department of Environmental and Climate Sciences at Brookhaven National Laboratory. His research focuses on the understanding of the microphysical, dynamical and radiative processes that act at the cloud- and meso-scale and their accurate representation in numerical models. He is also interested in radar technology and the development and application of novel phased-array and spaceborne radars in weather and climate research. Kollias is an international leader in the application of radars for cloud and precipitation research from ground-based and space-based platforms. Kollias has published over 140 peer-reviewed scientific articles in the areas of millimeter wavelength radar research, radar technology, signal processing and cloud and precipitation dynamics and microphysics.

Pavlos Kollias is the Director of the Center for Multiscale Applied Sensing (CMAS) at Brookhaven National Laboratory ( He is a member of the Mission Advisory Group and algorithm development team of the European Space Agency Earth Clouds Aerosols Radiation Experiment (EARTHCARE) Explorer Mission. He has served as a member at the National Science Foundation Engineering Research Center for the Collaborative Adaptive Sensing of the Atmosphere. Kollias also served for three years (2007-2009) as Associate Chief Scientist for the US DOE Atmospheric Radiation Measurements (ARM) program. He has served as the Chair of the American Meteorological Society (AMS) Committee on Radar Meteorology and has organized and chaired numerous sessions in international conferences. Kollias has also organized and participated as guest lecturer in several short courses in Europe, North America and Asia on the use of radars in atmospheric research.


  • Ph.D. in Meteorology, University of Miami, 2000.
  • M.S. in Atmospheric Science, The University of Athens, Greece, 1996.
  • B.S. in Physics, The University of Athens, Greece, 1994.

Areas of Interest

  • Cloud and Precipitation microphysics and dynamics
  • Boundary layer turbulence
  • Radar technology and meteorology
  • Instrumentation

Awards, Honors and Memberships

  • 2015: NASA Group Achievement Award “For exceeding all expectations for GPM operations, data processing, algorithm performance, science impact, and education and public outreach within one year after launch”.
  • 2013-2014: Humboldt Research Fellowship for experienced researchers, Germany
  • 2012-2017: Canada Research Chair in Radar Applications in Weather and Climate
  • 2007-2012: Canada Research Chair in Radar Applications in Weather and Climate
  • 2003-2004: Visiting Scientist Fellowship, Cooperative Institute for Research in Environmental Sciences, University of Colorado
  • 2003: NASA Group Achievement Award “for the Cirrus Regional Study of Tropical Anvils and Cirrus Layers – Florida Area Cirrus Experiment (CRYSTAL-FACE)


  • 2016-present Professor, Stony Brook University, Stony Brook NY
  • 2016-present Atmospheric Scientist, Brookhaven National Laboratory, Upton NY
  • 2016-present International Faculty, University of Cologne, Cologne Germany
  • 2012-2016 Associate Professor and Canada Research Chair, McGill University, Montreal Canada
  • 2007-2012 Assistant Professor and Canada Research Chair, McGill University, Montreal Canada
  • 2005-2007 Associate Scientist, Brookhaven National Laboratory, Upton NY
  • 2004-2005 Assistant Scientist, University of Miami, Miami, FL
  • 2003-2004 Visiting Fellow Scientist, University of Colorado, Boulder, CO
  • 2002-2003 Assistant Scientist, University of Miami, Miami, FL
  • 2001-2002 Postdoctoral Associate, University of Miami, Miami, FL

External Service

  • Director, Center for Multiscale Applied Sensing, Brookhaven National Laboratory, 2017-present
  • Member, National Offshore Wind R&D Consortium Advisory Group, 2019-present
  • Observer, Mission Advisory Group, Phase D/E1, ESA EarthCARE mission, 2017-present
  • Associate Editor, AGU Journal of Geophysical Research – Atmospheres, 2012-present
  • Associate Editor, EGU Atmospheric Measurements Techniques Journal, 2019-present
  • Adjunct Researcher, National Observatory of Athens, Greece, 2018 - present
  • Adjunct Professor, McGill University, 2016-present
  • Adjunct Associate Professor, University of Miami, 2011-2017
  • Member, BNL/ECS Department Science Advisory Committee, 2017-2018
  • Member, Mission Advisory Group, Phase C/D, ESA EarthCARE mission, 2012-2017
  • Leader, Radar Science Group, DOE Atmospheric Systems Research program 2012-2018
  • Member, DOE ARM User Executive Committee, 2015-2018

Selected Publications

Kollias, P., Bharadwaj, N., Clothiaux, E. E., Lamer, K., Oue, M., Hardin, J., Isom, B., Lindenmaier, I., Matthews, A., Luke, E. P., Giangrande, S. E., Johnson, K., Collis, S., Comstock, J., and Mather, J. H.  The ARM Radar Network: At the Leading-edge of Cloud and Precipitation Observations.  Bull. Am. Meteorol. Soc., E588-E607, doi:10.1175/BAMS-D-18-0288.1 (2020).

Battaglia A., P. Kollias, R. S. Dhillon, R. Roy, S. Tanelli, K. Lamer, M. Grecu, M. Lebsock, D. C. Watters, K. Mroz, G. M. Heymsfield, L. Li, K. Furukawa, 2020: Space-borne cloud and precipitation radars: status, challenges and ways forward. Submitted to Reviews of Geophysics.

Lamer, K., Kollias, P., Battaglia, A., and Preval, S.: Mind-the-gap part I: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars, Atmos. Meas. Tech. Discuss.,, in review, 2020.

Oue, M., Tatarevic, A., Kollias, P., Wang, D., Yu, K., and Vogelmann, A. M.: The Cloud Resolving Model Radar Simulator (CR-SIM) Version 3.2: Description and Applications of a Virtual Observatory, Geosci. Model Dev. Discuss.,, in review, 2019.

Kumjian, M. R., K. A. Bowley, P. M. Markowski, K. Lombardo, Z. Lebo, and P. Kollias: Snowflake Selfies: A Low-Cost, High-Impact Approach Toward Student Engagement in Scientific Research (with their Smartphones). Bull. Amer. Meteor. Soc., in revision, 2020.

Jacob, M., P. Kollias, F. Ament, V. Schemann and S. Crewell, 2020: Multi-layer Cloud Conditions in Trade Wind Shallow Cumulus –Confronting Models with Airborne Observations. Geosci. Model Dev. Discuss.

Holger Siebert, Ph.D.; Kay Szodry; Ulrike Egerer; Birgit Wehner; Silvia Henning; Karine Chevalier; Janine Lückerath; Oliver Welz; Kai Weinhold; Felix Lauermann; Matthias Gottschalk; Andre Ehrlich; Manfred Wendisch; Paulo Fialho; Greg Roberts; Nithin Allwayin; Simeon Schum; Raymond A. Shaw; Claudio Mazzoleni; Lynn Mazzoleni; Jakub Nowak; Szymon Malinowski; Katarzyna Karpinska; Wojciech Kumala; Dominika Czyżewska; Edward Luke; Pavlos Kollias; Robert Wood; Juan Pedro Mellado. Observations of aerosol, cloud, turbulence and radiation properties at the top of the marine boundary layer over the Eastern North Atlantic Ocean: The ACORES campaign. Bull. Amer. Meteor. Soc., in revision, 2020.

Kumjian, M. R., D. M. Tobin, M. Oue and P. Kollias, 2020: Microphysical Insights into Ice Pellet Formation Revealed by Fully Polarimetric Ka-band Doppler Radar. Submitted to JGR-Atmospheres.

Yang, F., R. McGraw, E. Luke, D. Zhang, P. Kollias, and A. Vogelmann, A new approach to estimate supersaturation fluctuations in stratocumulus cloud using ground-based remote sensing measurements, Atmospheric Measurement Techniques, doi: 10.5194/amt-12-5817-2019, 2019.

Zhang, D., A. Vogelmann, P. Kollias, E. Luke, F. Yang, D. Lubin, and Z. Wang, Comparison of Antarctic and Arctic Single-layer Stratiform Mixed-phase Cloud Properties Using Ground-based Remote Sensing Measurements, Journal of Geophysical Research: Atmosphere, doi: 10.1029/2019JD030673, 2019.

Zhu, Z., Lamer, K., Kollias, P., & Clothiaux, E. E. (2019). The vertical structure of liquid water content in shallow clouds as retrieved from dual-wavelength radar observations. Journal of Geophysical Research: Atmospheres, 2019; 124: 14184-14197.

Acquistapace, C., U. Löhnert, M. Maahn, and P. Kollias, 2019: A New Criterion to Improve Operational Drizzle Detection with Ground-Based Remote Sensing. J. Atmos. Oceanic Technol., 36, 781 801,

Kollias, P., Puigdomènech Treserras, B., and Protat, A.: Calibration of the 2007-2017 record of ARM Cloud Radar Observations using CloudSat, Atmos. Meas. Tech.,, Accepted, 2019.

Battaglia, A. and Kollias, P.: Evaluation of differential absorption radars in the 183 GHz band for profiling water vapour in ice clouds, Atmos. Meas. Tech., 12, 3335-3349,, 2019.

Oue, M., Kollias, P., Shapiro, A., Tatarevic, A., and Matsui, T.: Investigation of observational error sources in multi-Doppler-radar three-dimensional variational vertical air motion retrievals, Atmos. Meas. Tech., 12, 1999-2018,, 2019.

Lamer, K., Puigdomènech Treserras, B., Zhu, Z., Isom, B., Bharadwaj, N., and Kollias, P.: Characterization of Shallow Oceanic Precipitation using Profiling and Scanning Radar Observations at the Eastern North Atlantic ARM Observatory, Atmos. Meas. Tech.,, Accepted, 2019.

Drueke, S., Kirshbaum, D., and Kollias, P., 2019: Evaluation of Shallow-Cumulus Entrainment Rate Retrievals Using Large-Eddy Simulation. J. Geophys. Res. Atmos., 124.

Mech, M., Kliesch, L.-L., Anhäuser, A., Rose, T., Kollias, P., and Crewell, S.: Microwave Radar/radiometer for Arctic Clouds MiRAC: First insights from the ACLOUD campaign, Atmos. Meas. Tech. Discuss.,, Accepted, 2019.

Oh, S., Kollias, P., Lee, J. , Lee, S. , Lee, Y. H. and Jeong, J. (2019), Rain-Rate Estimation Algorithm using Signal Attenuation of Ka-band Cloud Radar. Meteorol Appl. Accepted. doi:10.1002/met.1825.

Pfitzenmaier, L., A. Battaglia and P. Kollias: The Impact of the Radar-Sampling Volume on Multiwavelength Spaceborne Radar Measurements Using Airborne Radar Observations. Remote Sensing 11(19): 2263 (2019).

Endo, S., Zhang, D., Vogelmann, A. M., Kollias, P., Lamer, K., Oue, M., et al. (2019). Reconciling differences between large-eddy simulations and Doppler lidar observations of continental shallow cumulus cloud-base vertical velocity. Geophysical Research Letters, 46, 11539-11547.

Grosvenor, D. P., O. Sourdeval, A. Ackerman, M. D. Alexandrov, R. Bennartz, B. Cairn, C. Chiu, M. Christensen, G. Feingold, A. Hunerbein, C. Knist, P. Kollias, A. Marshak, D. McCoy, D. Merk, D. Painemal, J Rausch, D. Rosenfeild, H. Russchenberg, P. Seifert, K. Sinclair, P. Stier, B. van Diedenhoven M. Weindisch, F. Werner, R. Wood, P. Zuidema, Z. Zhang and J. Quaas, 2018:Remote sensing of cloud droplet number concentration in warm clouds: Review of current state of knowledge and perspectives. Rev. Geophys., doi:10.1029/2017RG000593.

Oue, M., Kollias, P., Ryzhkov, A., and Luke, E. P. Towards Exploring the Synergy between Cloud Radar Polarimetry and Doppler Spectral Analysis in Deep Cold Precipitating Systems in the Arctic. J. Geophys. Res. Atmos. 23, 2797-2815, doi:10.1002/2017JD027717 (2018).

Yang, F., Luke, E. P., Kollias, P., Kostinski, A. B., and Vogelmann, A. M. Scaling of drizzle virga depth with cloud thickness for marine stratocumulus clouds. Geophy. Res. Lettrs 45, 3746-3753. doi:10.1029/2018GL077145 (2018).

Yang, F., P. Kollias, R.A. Shaw, and A. M. Vogelmann, Cloud droplet size distribution broadening during diffusional growth: ripening amplified by deactivation and reactivation, Atmos. Chem. Phys., 18, 7313-7328, doi:10.5194/acp-18-7313-2018.

Zhang, D., Wang, Z., Kollias, P., Vogelmann, A. M., Yang, K., and Luo, T. Ice particle production in mid-level stratiform mixed-phase clouds observed with collocated A-Train measurements. Atmos. Chem. Phys. 18, 4317-4327, doi:10.5194/acp-18-4317-2018 (2018).

Zhang, Y., Xie, S., Klein, S. A., Marchand, R., Kollias, P., Clothiaux, E. E., Lin, W., Johnson, K., Swales, D., Bodas-Salcedo, A., Tang, S., Haynes, J. M., Collis, S., Jensen, M., Bharadwaj, N., Hardin, J., and Isom, B. The ARM Cloud Radar Simulator for Global Climate Models: A New Tool for Bridging Field Data and Climate Models. Bull. Amer. Meteorol. Soc. 99, 21-26, doi:10.1175/BAMS-D-16-0258.1 (2018).

Zhou, X., Ackerman, A. S., Fridlind, A. M., and Kollias, P. Simulation of Mesoscale Cellular Convection in Marine Stratocumulus. Part I: Drizzling Conditions. J. Atmos. Sci. 75, 257-274, doi:10.1175/JAS-D-17-0070.1 (2018).

Borque, P., E.P. Luke, P. Kollias, and F. Yang, 2018: Relationship between Turbulence and Drizzle in Continental and Marine Low Stratiform Clouds. J. Atmos. Sci., 75,4139-4148,

Chen, Y. -S., J. Verlinde, E. E. Clothiaux, A. S. Ackerman, A. M. Fridlind, M. Chamecki, P. Kollias, M. P. Kirkpatrick, B.-C. Chen, G. Yu, and A. Avramov, 2018: On the forward modeling of radar Doppler spectrum width from LES: Implications for model evaluation. Journal of Geophysical Research: Atmospheres, 123, 7444-7461.

Illingworth, A., A. Battaglia, J. Bradford, M. Forsythe, P. Joe, P. Kollias, K. Lean, M. Lori, J.-F. Mahfouf, S. Melo, R. Midthassel, Y. Minro, J. Nicol, R. Potthast, M. Rennie, T. Stein, S. Tanelli, F. Tridon, C. Walden, M. Wolde, 2018. WIVERN: A new satellite concept to provide global in-cloud winds. Bull. Amer. Meteor. Soc.

Kollias, P., A. Battaglia, A. Tatarevic, K. Lamer, F. Tridon, and L. Pfitzenmaier: The EarthCARE cloud profiling radar (CPR) doppler measurements in deep convection: challenges, post-processing, and science applications, Proc. SPIE 10776, Remote Sensing of the Atmosphere, Clouds and Precipitation VII, 107760R; doi:10.1117/12.2324321, 2018.

Kollias, P., D. J. McLaughlin, S. Frasier, M. Oue, E. Luke and A. Sneddon, "Advances and applications in low-power phased array X-band weather radars," 2018 IEEE Radar Conference (RadarConf18), Oklahoma City, OK, USA, 2018, pp. 1359-1364. doi: 10.1109/RADAR.2018.8378762.

Lamer, K., Fridlind, A. M., Ackerman, A. S., Kollias, P., Clothiaux, E. E., and Kelley, M.: (GO)2-SIM: A GCM-Oriented Ground-Observation Forward-Simulator Framework for Objective Evaluation of Cloud and Precipitation Phase, Geosci. Model Dev. Discuss.,

Zheng, G., Wang, Y., Aiken, A. C., Gallo, F., Jensen, M. P., Kollias, P., Kuang, C., Luke, E., Springston, S., Uin, J., Wood, R., and Wang, J.: Marine boundary layer aerosol in the eastern North Atlantic: seasonal variations and key controlling processes, Atmos. Chem. Phys., 18, 17615-17635,, 2018.