Dr. Steven "Steve" Platnick stepped down from his role at NASA on August 8, 2025, after more than three decades of public service. Steve began his career at NASA as a physical scientist at Goddard Space Flight Center in 2002. He moved to the Earth Science Division in 2009, where he has served in various senior management roles, including as the Earth Observing System (EOS) Senior Project Scientist. In this role, he led the EOS Project Science Office and continued periodic meetings of the EOS Project Scientists, initiated by Michael King during his tenure. Steve expanded these meetings to include representatives of non-EOS Earth observing missions and representatives from Earth Science Mission Operations (ESMO). In addition, Steve was named Deputy Director for Atmospheres in the Earth Science Division in January 2015 and served in this position until July 2024.
During his time at NASA, Steve played an integral role in the development, sustainability, and advancement of NASA's Earth Observing System platforms. From January 2003 - February 2010, Steve served as Deputy Project Scientist for Aqua. In this role, he applied his expertise in theoretical and experimental studies of satellite, aircraft, and ground-based cloud remote sensing to improve algorithms to benefit the data gathered from remote observing systems.
Taking the Lead to Improve Algorithms
Steve was actively involved in the Moderate Resolution Imaging Spectroradiometer (MODIS) Science Team, serving as the MODIS Atmosphere Team Lead. Steve helped advance several key components of the MODIS instrument, which flies on NASA's Terra and Aqua platforms. He led a team that enhanced, maintained, and evaluated MODIS algorithms that support the Level-2 (L2) Cloud Optical/Microphysical Properties components (e.g., COD06 and MYD06) for MODIS on Terra and Aqua. The algorithms were designed to retrieve thermodynamic phase, optical thickness, effective particle radius, and water path for liquid and ice clouds. The team's work also contributes to L3 products that address cloud mask, aerosols, clouds, and clear sky radiance for data within 1° grids over one-day, eight-day, and one-month repeat cycles. Under Steve's leadership, the team also developed L2 products (e.g., MODATML2 and MYDATML2) that include essential atmosphere datasets of samples collected at 5-10 km (3-6 mi) that is consistent with L3 products to ease storage requirements of core atmospheric data.
Steve is also a member of the Suomi-National Polar-orbiting Partnership (Suomi NPP) Atmosphere Team, working on operational cloud optical and microphysical products. In this role, he contributed to algorithm development and refinement for the Cloud Product. In particular, he helped address a critical gap in the Visible Infrared Imaging Radiometer Suite (VIIRS) spectral channel, which was not designed to collect information for carbon dioxide (CO2) slicing and water vapor data in the same way as MODIS. Steve and his colleagues developed a suite of L2 algorithms for the spectral channels that were common to both MODIS and VIIRS to address cloud mask and cloud optical/microphysical properties. Through these efforts, the project has established a continuous cloud data record gathered from both instruments from 2017 to the present.
Steve also participated in numerous other working groups during the past 30 years. He participated in the Global Energy and Water Exchanges (GEWEX) Cloud Assessment Working Group (2008-present), Arctic Radiation-Cloud-Aerosol-Surface Interaction Experiment (ARCSIX) Science Team (2023-present), ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) Earth-Venture Suborbital (EVS)-2 Science Team (2014-2023), Deep Space Climate Observatory (DSCOVR) Science Team (2014-present), Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Science Team (2014-2023), PACE Science Definition Team, Deputy Chair (2011-2012), Glory Science Team (2010-2014) NASA Observations for Modeling Intercomparison Studies (obs4MIPs) Working Group (2011), Advanced Composition Explorer (ACE) Science Definition Team (2009-2011), and Geostationary Operational Environmental Satellites (GOES) R-series Advanced Baseline Imager (ABI) Cloud Team (2005-2009).
Steve has also participated in numerous major airborne field campaigns in various roles, including: GSFC Lidar Observation and Validation Experiment (GLOVE, 2025), PACE Postlaunch Airborne eXperiment (PAX, 2024), the Westcoast & Heartland Hyperspectral Microwave Sensor Intensive Experiment (WH2yMSIE, 2024), ORACLES Science Team (2015-2019), Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) Science Team (2011-2015), Tropical Composition, Cloud and Climate Coupling (TC4) Management Team (2007), Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment (CRYSTAL-FACE) Science Management Team (2002), Southern Africa Fire-Atmosphere Research Initiative (SAFARI, 2000), First ISCCP Regional Experiment (FIRE) Arctic Cloud Experiment (ACE) (1998), Mikulski Archive for Space Telescopes (MAST, 1994), and ACE (1992).
Supporting Earth Science Communications
Through his senior leadership roles within ESD Steve has been supportive of the activities of NASA's Science Support Office (SSO). He has participated in many NASA Science exhibits at both national and international scientific conferences, including serving as a Hyperwall presenter numerous times. He has met with task leaders frequently and has advocated on behalf of the SSO to management at NASA Headquarters, GSFC, and Global Sciences & Technology Inc.
For The Earth Observer newsletter publication team in particular, Steve replaced Michael King as Acting EOS Senior Project Scientist in June 2008, taking over the authorship of "The Editor's Corner" beginning with the May-June 2008 issue [Volume 20, Issue 3]. The Acting label was removed beginning with the January-February 2010 issue [Volume 22, Issue 1]. Steve has been a champion of continuing to retain a historical record of NASA meetings to maintain a chronology of advances made by different groups within the NASA Earth Science community. He was supportive of the Executive Editor's efforts to create a series called "Perspectives on EOS," which ran from 2008-2011 and told the stories of the early years of the EOS Program from the point of view of those who lived them. He also supported the development of articles to commemorate the 25th and 30th anniversary of The Earth Observer. Later, Steve helped guide the transition of the newsletterfrom a print publication - the November-December 2022 issue was the last printed issue - to fully online by July 2024, a few months after the publication's 35th anniversary. The Earth Observer team will miss Steve's keen insight, historical perspective, and encouragement that he has shown through his leadership for the past 85 issues of print and online publications.
A Career Recognized through Awards and Honors
Throughout his career, Steve has amassed numerous honors, including the Robert H. Goddard Award for Science: MODIS/VIIRS Cloud Products Science Team (2024) and the William Nordberg Memorial Award for Earth Science in 2023. He received the Verner E. Suomi Award from the American Meteorological Society (AMS) in 2016 and was named an AMS Fellow that same year.
Steve has received numerous NASA Group Achievement Awards, including for the Cloud, Aerosol and Monsoon Processes Philippines Experiment (CAMP2Ex) Field Campaign Team (2020), Fire Influence of Regional to Global Environments and Air Quality (FIREX-AQ) Field Campaign Team (2020), ORACLES Field Campaign Team (2019), obs4MIPs Working Group (2015), SEAC4RS Field Campaign Team (2015), Advanced Microwave Scanning Radiometer for EOS (AMSR-E) Instrument Recovery Team (2013), Climate Absolute Radiance and Refractivity Observatory (CLARREO) Mission Concept Team (2012), Earth Science Constellation Red Team (2011), Science Mission Directorate ARRA Team (2011), TC4 Team (2009), MODIS Science Data Support Team (2007), Aqua Mission Team (2003), CRYSTAL-FACE Science Team (2003), and SAFARI 2000 International Leadership Team (2002).
Steve received two NASA Agency Honor Awards - the Exceptional Service Medal in 2015 and the Exceptional Achievement Medal in 2008. He was also part of the NASA Agency Team Excellence Award in 2017 for his work with the Satellite Needs Assessment Team. The Laboratory for Atmospheres honored him with the Best Senior Author Publication Award in 2001 and the Scientific Research Peer Award in 2005.
Steve received his bachelor's degree and master's degree in electrical engineering from Duke University and the University of California, Berkeley, respectively. He earned a Ph.D. in atmospheric sciences from the University of Arizona. He began his career at the Joint Center for Earth Systems Technology (JCET) at University of Maryland Baltimore County in 1996 as a research associate professor. He held this appointment until 2002. Steve has published more than 150 scholarly articles.
