Piotr Flatau is a researcher in the Climate, Atmospheric Science and Physical Oceanography (CASPO) division at Scripps Institution of Oceanography, University of California San Diego since 1992, as well as a professor in Poland since 2016. He has made notable contributions to the field of atmospheric and climate sciences, particularly in the areas of aerosols and clouds, radiative transfer, and tropical dynamics. His research has focused on applied physics problems of atmospheric science such as exact solutions to light scattering or the development of cloud microphysics parameterizations, but he has been involved in major atmospheric and oceanic observational field projects and instrumentation. In addition to his research, Flatau is also teaching and mentoring students in the United States, Poland and Indonesia.
Piotr Flatau was born in Poland. He graduated from Tadeusz Reytan High School in Warsaw. At that time he was sailing and became a long-term friend with philosopher and biologist, Jesuit Piotr Lenartowicz. Flatau received his M.Sc.  in theoretical physics from the Physics Department of the University of Warsaw under the guidance of Jerzy Mycielski in 1977 and was interested in statistical mechanics problems (Łukasz Turski). He later earned an M. Sc.  in Atmospheric Sciences in 1985 and a Ph.D.  in Atmospheric Sciences in 1992 from Colorado State University, where he worked under guidance of cloud physicist William Cotton and radiative transfer and remote sensing expert Graeme Stephens; Flatau was the first Ph. D. student of Graeme Stephens. Flatau received a D.Sc.  in physics from the University of Warsaw in 2012 and is a Foreign Member of the Polish Academy of Sciences since 2017. He served as an associate editor for the Journal of the Atmospheric Sciences from 1993 to 2000 when the editor was William Cotton and he was editor for Pure and Applied Geophysics (PAGEOPH) from 1994 to 1996. He was a Member of the U.S. Climate Variability and Predictability (CLIVAR) Process Study and Model Improvement Panel (2008-2010) and he was a recipient of the Office of Naval Research (ONR) Young Investigator Program (YIP) and DURIP award (2007).
While at Scripps Institution of Oceanography Flatau was working initially with V. Ramanathan and Paul Crutzen during several large climate-related field projects such as CEPEX (1993, Majuro), INDOEX (1999, Indian Ocean and Arabian Sea), and MINOS (2001, Crete, Greece) which were run by the NSF Center for Clouds, Chemistry and Climate (C4). Subsequently, he has been the principal investigator for numerous research projects, including land-based projects such as the NSF-NERC Equatorial Line Observations project (2018-2023, Indonesia), and has been a seagoing researcher, studying ocean color and remote sensing atmospheric corrections during the NASA Sensor Intercomparing And Merger For Biological Interdisciplinary Oceanic Studies (SIMBIOS, Indian Ocean) and the California Cooperative Oceanic Fisheries Investigations (CalCOFI, 1993) with Gregory Mitchell. Flatau has also been a member of various panels and science teams, such as the U.S. Climate Variability and Predictability Process Study. As a Ph. D. student in Graeme Stephens’ group he was involved in cirrus cloud research as part of the First International Satellite Cloud Climatology Project Regional Experiment (FIRE Cirrus) with field projects in 1986 and 1992.
Piotr Flatau has made significant contributions to cloud physics and cloud microphysics through his work on the Colorado State University mesoscale model (CSU-RAMS ) cloud microphysics module  which has been subsequently used in various mesoscale models and the development of a closed-form solution for the collection growth equation. He was involved in research on the microphysical and radiative properties of cirrus clouds  which was one of the first to demonstrate that cirrus cloud microphysics can be important for climate cloud forcing. During the Mediterranean Intensive Oxidant Study (MINOS), conducted in the summer of 2001, Piotr Flatau with Krzysztof Markowicz found that Saharan dust particles reduce solar radiation penetration to the surface in that part of the globe .
Since 1990, Flatau has made significant contributions to the field of computational electromagnetics through his development, with astrophysicist Bruce Draine, of a powerful technique for calculating light scattering by arbitrary particles in the discrete dipole approximation (DDSCAT). This technique is now widely recognized as one of the most robust methods for modeling scattering by non-spherical particles, such as ice crystals, dust, soot, and marine phytoplankton. The technique has found numerous applications in atmospheric science, photonics, and other fields where the interaction of light with matter is of interest. Their 1994 paper on Discrete-Dipole Approximation for Scattering Calculations  is referenced now (Google Scholar) > 4200 times.
For almost a decade Piotr Flatau was involved in field projects (CAPE, last project 2019) focused on mid-level and upper-level clouds conducted by the Naval Research Laboratory in the Kennedy Space Center near Cape Canaveral, Florida and led by Jerrome Schmidt. These projects utilized a high-resolution dual-polarization, C-band Doppler radar that was initially developed in 1994 and routinely used by NASA to monitor Space Shuttle launch debris. The radar was capable of detecting single hydrometeors and provided unprecedented detail of the internal structure and circulation of clouds with 0.5m range resolution . Together with his colleagues, Flatau observed individual droplets in clouds from this radar at 2-7 kilometers above the surface (2019). Their collaboration documented the structure of a thin and narrow band of mixed-phase altocumulus clouds  and the structure of nimbostratus . For many years Piotr Flatau and his students worked with the Naval Research Laboratory aerosol group led by Douglas Westphal which led to development with Marcin Witek of a sea-salt module  for the Navy Aerosol Analysis and Prediction System (NAAPS) model. They also participated in dust studies in the Persian Gulf and other field projects (UEA2 project).
Together with his wife Maria Flatau, who is a tropical meteorologist, and their students Dariusz Baranowski and Beata Latos, Flatau has made significant contributions to the field of tropical atmospheric and oceanic sciences, including research on the Madden-Julian Oscillation, which was one of the first studies to demonstrate the importance of feedback between sea surface temperature modification and convective cluster development in Madden-Julian Oscillation propagation  . They also analyzed the climatology of double monsoon onset and identified the key factors influencing this phenomenon . In addition, Flatau’s and his students research on floods in Sumatra revealed the critical role played by convectively coupled Kelvin waves (2020). Their research on the tropical cyclones dealt with the unusual near-equatorial cyclogenesis associated with multiple wave interactions(2023).
As a graduate student advisor, Piotr Flatau has supervised several M.Sc. students including Anni Fitriany from Indonesia who worked on policy topics related to fires (2021) and Ph.D. students in the field of environmental sciences including Beata Latos, who will complete her disertation in 2023, Dariusz Baranowski, who completed his Ph.D. in 2015 on air-sea interaction in tropical atmosphere, Joanna Remiszewska, who completed her Ph.D. in 2009 on the optical properties of atmospheric aerosols in the Persian Gulf, Marcin Witek, who completed his Ph.D. in 2008 on sea salt aerosol in global transport models, and Krzysztof Markowicz, who completed his Ph.D. in 2003 on experimental determination of solar and infrared radiative forcing. He was teaching undergraduate and graduate classes both in University of Warsaw and Scripps Institution of Oceanography.
For several years (2018-2023) and currently he has been involved in meteorology capacity building in Indonesia. He was one of the first to write about climate change in his native Poland (2010-2016, “takiklimat.blox.pl”) and was subsequently a founding member (2013) and is on science board of the popular site “Nauka o Klimacie” (Science of Climate). He wrote numerous Wikipedia and popular science articles related to atmospheric science and climate change. He was the weather forecaster for the Polish National Sailing Team during pre-Olympics regata in Qingdao, China in 2006 and meteorologist during Roman Paszke solo circumnavigation sailing on Gemini 3 against the prevailing winds (from east to west).
Piotr Flatau is a Polish author and translator known for his work in preserving and promoting the legacy of Argentine tango music in Poland. His translations of Argentine tango lyrics into Polish were used in the musical performance “TANGO FM” in 2015. The show follows a radio host played by Piotr Machalica. His songs were performed by Olga Avigail (Mieleszczuk) during the Singer’s Warsaw festival and on other occasions. Additionally, he wrote the book “Władysław Szlengel: The Forgotten Poems” with Katarzyna Zimek and he is the author of book and a documentary film on the history of his family: “Edward Flatau and his two daughters”. He published on history of neurology in Poland and Russia (2022).
 Flatau, P. J. (1978). Kinetics of the intraband absorption and magnetoabsorption coefficients in mixed semiconductors with composition fluctuations. Physica Status Solidi (b), 90(1), 127-132. https://doi.org/10.1002/pssb.2220900127  Flatau, P. J. (1985). Study of second-order turbulence closure technique and its application to atmospheric flows (M. Sc. dissertation). Colorado State University.  Flatau, P. J. (1992). Scattering by irregular particles in anomalous diffraction and discrete dipole approximations (Doctoral dissertation). Colorado State University.  Flatau, P. J. (2012). Accurate methods of single and multiple scateering, Habilitacja, Physics Department, University of Warsaw, Poland.  Flatau, P. J., Tripoli, G. J., Verlinde, J., & Cotton, W. R. (1989). CSU-RAMS cloud microphysics module: general theory and code documentation, Colorado State University.  Stephens, G. L., Tsay, S. C., Stackhouse Jr, P. W., & Flatau, P. J. (1990). The relevance of the microphysical and radiative properties of cirrus clouds to climate and climatic feedback. Journal of the Atmospheric Sciences, 47(14), 1742-1754.  Markowicz, K. M., Flatau, P. J., Ramana, M. V., Crutzen, P. J., & Ramanathan, V. (2002). Absorbing Mediterranean aerosols lead to a large reduction in the solar radiation at the surface. Geophysical Research Letters, 29(20), 29-1.  Draine, B. T., & Flatau, P. J. (1994). Discrete-dipole approximation for scattering calculations. JOSA A, 11(4), 1491-1499.  Flatau, M., Flatau, P. J., Phoebus, P., & Niiler, P. P. (1997). The feedback between equatorial convection and local radiative and evaporative processes: The implications for intraseasonal oscillations. Journal of the Atmospheric Sciences, 54(19), 2373-2386.  Schmidt, J. M., Flatau, P. J., Harasti, P. R., Yates, R. D., Delene, D. J., Gapp, N. J., … & Bennett, J. E. (2019). Radar detection of individual raindrops. Bulletin of the American Meteorological Society, 100(12), 2433-2450.  Schmidt, J. M., Flatau, P. J., & Harasti, P. R. (2017). Evidence for a Nimbostratus Uncinus in a Convectively Generated Mixed-Phase Stratiform Cloud Shield. Journal of the Atmospheric Sciences, 74(12), 4093-4116.  Witek, M. L., Flatau, P. J., Quinn, P. K., & Westphal, D. L. (2007). Global sea‐salt modeling: Results and validation against multicampaign shipboard measurements. Journal of Geophysical Research: Atmospheres, 112(D8).  Schmidt, J. M., Flatau, P. J., & Yates, R. D. (2014). Convective cells in altocumulus observed with a high-resolution radar. Journal of the Atmospheric Sciences, 71(6), 2130-2154.  Flatau, M. K., Flatau, P. J., & Rudnick, D. (2001). The dynamics of double monsoon onsets. Journal of Climate, 14(21), 4130-4146.