PMM Science Team

The NASA Precipitation Measurement Missions (PMM) Science Team conducts scientific research (including algorithm development, mission implementation, product validation, and data utilization) in support of TRMM and GPM Missions. The team comprises scientists funded by NASA and international investigators selected by NASA on the basis of no exchange of funds.


PMM Science Program Management Team:

Name Organization Title
Dr. Ramesh K. Kakar NASA Headquarters TRMM and GPM Program Scientist
Dr. Gail Skofronick-Jackson NASA Goddard Space Flight Center GPM Project Scientist and PMM Science Team Lead
Dr. George J. Huffman NASA Goddard Space Flight Center GPM Deputy Project Scientist
Dr. Scott A. Braun NASA Goddard Space Flight Center TRMM Project Scientist
Dr. Erich F. Stocker NASA Goddard Space Flight Center GPM Deputy Project Scientist for Data and Precipitation Processing System Project Manager
Dr. Walter A. Petersen NASA Marshall Space Flight Center Deputy Project Scientist, Ground Validation
David B. Wolff NASA Wallops Flight Facility GPM Ground Validation System Manager
Dr. Dalia B. Kirschbaum NASA Goddard Space Flight Center GPM Associate Deputy Project Scientist for Applications


2016 PMM group photo

PMM Principal Investigators and Proposals

Last Name First Name Affiliation Proposal Title
Adler Robert University of Maryland, College Park Climatology and Variations of Surface Precipitation: Use of GPM/TRMM in the Long-Term Record
Barros Ana Duke University 4D Integration of Satellite and IPHEx GV Observations with Physical Models to Improve the Representation of Orographic Precipitation Processes and Enhance Precipitation Measurement and Simulation in Mountainous Regions
Berg Wesley Colorado State University Improving Consistency in Precipitation Estimates from the GPM Radiometer Constellation Through Intercalibration, Sensitivity Analysis, and Bias Characterization
Bras Rafael Georgia Tech Research Corporation Data Assimilation and Downscaling of Remotely-Sensed Satellite Precipitation and Soil Moisture Data for Hydrologic Applications
Cecil Daniel NASA Marshall Space Flight Center Better Understanding GPM Radiometer Measurements Using Ground-Based Radar
Chandrasekar Chandra V. Colorado State University GPM Observations and Precipitation Microphysics: Satellite Algorithm Support, Product Validation, Enhancement, Interpretation, Precipitation Estimation and Applications
Chen Shuyi University of Miami, Key Biscayne TRMM-GPM Precipitation Tracking and Water Cycle of the MJO
Colle Brian State University of New York, Stony Brook Using OLYMPEX Field Data, Satellite Simulators, and Unique Surface Instrumentation to Improve Cloud Microphysical Parameterizations
Del Genio Anthony NASA Goddard Space Flight Center Analysis of Organized Convection and Synoptic Storms in TRMM-GPM Data and a General Circulation Model
Durden Stephen Jet Propulsion Laboratory GPM DPR Algorithm and Product Validation Using APR-2 Field Campaign Data
Famiglietti James Jet Propulsion Laboratory Precipitation Measurement Mission for Improved Forcing in Hyper-Resolution Land Surface Models
Ferraro Ralph National Oceanic and Atmospheric Administration, NESDIS/ORA NOAA's Continued Contributions to the Development and Utilization of NASA's GPM Products
Field Robert Columbia University Applying NASA Satellite Precipitation Products to Global Fire Prediction: Assimilating GPCP, TRMM and GPM into the Global Fire Weather Database
Foufoula-Georgiou Efi University of California, Irvine Advanced Inversion Algorithms for GPM Passive Microwave Retrievals and Multi-Sensor Merging
Grecu Mircea Morgan State University Improved Radar Models and Parameterizations for the GPM Combined Algorithm
Haddad Ziad Jet Propulsion Laboratory Parametrizing the Non-Linear Beam-Filling and the Multiple-Scattering for the GPM Radar, and Assimilating Sounder Observations into WRF
Heymsfield Gerald NASA Goddard Space Flight Center DPR Algorithm Improvement Using Airborne Radar Measurements
Houze Robert University of Washington, Seattle Precipitation Processes over the Globe
Huffman George NASA Goddard Space Flight Center Extending the IMERG Multi-Sensor Level 3 Precipitation Product Across the TRMM-GPM Era
Jones W. Linwood University of Central Florida Inter-Satellite Radiometric Calibration (XCAL) for GPM Constellation
Kalnay Eugenia University of Maryland, College Park Further Advances on Effective Assimilation of Precipitation with GPM and TRMM
Kidd Christopher University of Maryland, College Park A Physically-Based Scheme for the Retrieval of Precipitation from Cross-Track Sensors in the GPM Constellation
Kim Min-Jeong Morgan State University All-Sky GPM Microwave Imager (GMI) Radiance Data Assimilation Global Products from the GEOS-5 System in Support of the GPM Mission
Kirschbaum Dalia NASA Goddard Space Flight Center A Regional Analysis Framework for Evaluating Satellite Rainfall Extremes in Complex Terrain for Landslide Hazards Applications
Kirstetter Pierre-Emmanuel University of Oklahoma, Norman A Research Framework to Bridge the Global Precipitation Measurement (GPM) Level II and Level III using Multi-Radar/Multi-Sensor (MRMS)
Krishnamurti Tiruvalam Florida State University Two Decades of Variability in the Life Cycle of Asian Summer Monsoon Seasons as Seen from TRMM/GPM
Kulie Mark University of Wisconsin, Madison Snowfall in the GPM Era: Assessing GPM Snowfall and Ice Microphysical Retrievals Using Independent Spaceborne and Ground-Based Observations
Kummerow Christian Colorado State University Entraining Large Scale Environmental Information to Improve the GMI Rainfall Product
Kuo Kwo-Sen University of Maryland, College Park Improved and Augmented Database of Hydrometeor Single-Scattering Properties to Support Algorithm Development
Lau William University of Maryland, College Park Organization of Tropical Convection and Relationship with Extreme Precipitation Events
Li Xiaowen Morgan State University Constraining the Ice-Particle Collection Efficiency Using TRMM/GPM Observations, Field Campaign Data, and Cloud Models with Explicit Bin Microphysics
Liao Liang Morgan State University Rain and Snow Particle Size Distribution Models and Their Application to the DPR Retrieval Algorithm
Liu Chuntao Texas A&M, Corpus Christri Validation of GPM Precipitation Retrievals Under Different Precipitation Regimes Using Precipitation Features and Ground Validation (GV) Observations
Liu Guosheng Florida State University Building Algorithm Components for GPM Snowfall Retrieval
Liu W. Timothy Jet Propulsion Laboratory Oceanic and Terrestrial Rainfall Linkage in Global Water Balance
Mace Gerald University of Utah, Salt Lake City The Effects of Ice Crystal Population Properties on Radar-Radiometer Retrievals of Precipitation Processes in Stratiform Clouds
McKague Darren University of Michigan, Ann Arbor Intercalibration of the GPM Constellation Radiometers: Constellation Monitoring, Anomaly Resolution, and Uncertainty Quantification
Meneghini Robert NASA Goddard Space Flight Center Path Attenuation Estimates from the Dual-Frequency Precipitation Radar
Munchak Stephen NASA Goddard Space Flight Center Improved Representation of Active and Passive Surface Characteristics in the GPM DPR-GMI Combined Precipitation Algorithm
Naud Catherine Columbia University Analysis of GPM Observations to Improve our Understanding of Midlatitude Precipitation: a Process-Oriented Study of Extratropical Cyclones
Nesbitt Stephen University of Illinois, Urbana-Champaign Impact of a Priori Assumptions on GPM Retrievals
Notaros Branislav Colorado State University Toward a More Statistically Robust, Generalized Process Evaluation Framework of Bin and Bulk Microphysics in Winter Precipitation Using NASA GV and GPM-DPR Data
Olson William University of Maryland Baltimore County Integration and Testing of Improved Ice and Mixed-Phase Precipitation Models for GPM Combined Radar-Radiometer Retrieval Algorithm Applications
Petersen Walter NASA Marshall Space Flight Center Validation of GPM Precipitation Retrieval Algorithms Across the Precipitation Continuum
Peters-Lidard Christa NASA Goddard Space Flight Center Dynamic Emissivity Estimates to Support Physical Precipitation Retrievals for GPM
Petty Grant University of Wisconsin, Madison Passive Microwave Retrievals of Precipitation at High Latitudes
Rutledge Steven Colorado State University Radar Studies of Convection in Support of PMM
Schreck Carl North Carolina State University Multiscale Interactions Between the MJO, Equatorial Waves, and the Diurnal Cycle over the Maritime Continent
Schumacher Courtney Texas A & M, College Station From the Tropics to the Midlatitudes: A Seamless Analysis of Convective and Stratiform Rain and Latent Heating Using GPM
Shepherd James University of Georgia, Athens The Energy-Water-Food Nexus Within the Backdrop of an Urbanized Globe: How Can GPM Help?
Soden Brian University of Miami, Key Biscayne A New Method for Statistical Downscaling of Precipitation and Application to South Florida Water Management
Tanelli Simone Jet Propulsion Laboratory Enhanced Algorithms for the Dual Frequency Precipitation Radar
Tao Wei-Kuo NASA Goddard Space Flight Center Advancing the Retrieval of Latent Heating for PMM with Improved Simulations of Convective, Synoptic, and Cold Season Systems and Their Associated Microphysical and Precipitation Processes
Turk Francis Jet Propulsion Laboratory Enhancements to GPM Radiometer-Based Precipitation Estimates Under a Variety of Surface and Atmospheric Conditions
Williams Christopher University of Colorado, Boulder Quantifying Melting Layer Attenuation and DSD Variability Within DPR Instantaneous Field-of-Views and Evaluating their Impact on DPR Observations and Retrieval Algorithms
Wong Sun Jet Propulsion Laboratory Connecting Precipitation to Clouds and the Large-Scale Circulation by Atmospheric Processes: Water-Budget Oriented Analyses
Wood Norman University of Wisconsin, Madison Assessing Precipitation Microphysical Structure Aloft Using Cold-Season Ground Validation Observations
Wu Huan University of Maryland, College Park Improved Global Flood Monitoring and Forecasting with GPM Precipitation and Hydrological Models
Zeng Xiping US Army Research Laboratory Using GPM Data to Examine the Effects of Cloud Dynamics on Microphysics
Zhang Fuqing Pennsylvania State University Improving Weather Prediction and Precipitation Estimation Through Advanced Ensemble Assimilation Using GPM Microwave Brightness Temperature with Coherent Microphysics Parameterization and Radiative Transfer Models


PMM Principal Investigators funded under NASA Internal Work Packages

GPM Algorithm Work Packages (Jan 2018 Summary)

NASA Headquarters has authorized a new funding strategy called "Work Packages" whereby key Principal Investigators at NASA centers who are repeatedly funded under ROSES calls are preselected outside of the ROSES call. This is a listing of the approved Work Package Principal Investigators and their topics for the 10th PMM ROSES Science Team (nominally 2018-2020).

Principal Investigator Title Task Summary
Cecil, Daniel Better Understanding GPM Radiometer Measurements Using Ground-Based Radar GPM, TRMM and related satellites have observed a huge number of precipitating systems around the globe. Pairing high-quality ground-based radar data with coincident satellite observations helps us learn to better interpret the satellite data, and to apply that understanding to satellite observations from otherwise data-sparse regions. This work aims to (a) improve understanding of how different hydrometeor types (and their vertical profiles and amounts) relate to observed satellite measurements; (b) investigate precipitation retrieval quality (error characteristics and biases) associated with particular hydrometeor types or profiles; (c) investigate characteristics of precipitation systems (and their related weather and climate patterns) around the globe.

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Huffman, George Extending the IMERG Multi-Sensor Level 3 Precipitation Product into Polar Regions

Comprehensive science algorithm development, implementation, maintenance, and validation, including user support, for quasi-global combined-satellite precipitation estimates at fine time/space scales, both in near-real and post-real time. This work includes extending the Integrated Multi-satellitE Retrievals for GPM (IMERG) to polar regions.

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Meneghini, Robert Path Attenuation Estimates from the Dual-Frequency Precipitation Radar

Development, scientific enhancement and validation of the Dual-Frequency Precipitation Radar (DPR) Surface Reference Technique (SRT) will be pursued by extending the dual-frequency version of the method (DSRT) to the new proposed scan geometry.  In addition, hybrid path attenuation estimates will be formulated by merging the SRT with the the Hitschfeld-Bordan (HB) method of attenuation correction, which performs well at light rain rates. Tests of the performance of the hybrid estimates will be done by adding new code and new output variables to existing operational codes.

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Munchak, Stephen   Improved Representation of Active and Passive Surface Characteristics in the GPM DPR-GMI Combined Precipitation Algorithm

Continue to improve representation of surface properties through physical and statistical models that account for correlated properties of emissivity and radar backscatter in the CORRA forward model. Integrate retrievals of surface and atmospheric state (including ocean surface wind, land emissivity, water vapor, clouds, and light precipitation) in regions where DPR does not detect precipitation.

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Olson, William Continued Development and Validation of Ice- and Mixed-Phase Precipitation Models for the GPM Combined Radar-Radiometer Algorithm

The overall effort is aimed at the development, delivery, maintenance, and validation of the Combined Radar-Radiometer Algorithm (CORRA) by improving the physical parameterizations of precipitation in all phases.  The science emphasis will be on the further exploitation of non-spherical ice and mixed-phase precipitation particle models, as well as particle size/habit distribution evolution simulations, to support improved descriptions of the bulk radiative properties of these precipitation types in the algorithm. Precipitation phase transitions in stratiform, convective, and near-convective regimes will be addressed. Validation of particle models will employ airborne remote sensing and in situ data from recent field campaigns, as well as GPM DPR-GMI data and coincident ground observations.

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Petersen, Walter Validation of GPM Precipitation Retrieval Algorithms across the Precipitation Continuum

Existing GPM-GV field and Validation Network datasets collected in warm and cold-season regimes are used to relate 3-D precipitation character and process variability to GPM retrieval algorithm constraints and performance. GV polarimetric radar and disdrometer-derived quantities of precipitation rate/content, type (rain, snow, convective, stratiform), and size distribution are processed and analyzed to relate dominant inter- and intra-footprint scale precipitation process/parameter variability to performance and improvement of key GPM algorithm components including path integrated attenuation, non uniform beam filling, retrieval of the rain drop size distribution, and estimation of rain and snow water-equivalent rates.

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Peters-Lidard, Christa Dynamic Emissivity Estimates to Support Physical Precipitation Retrievals for GPM (continued)

This work will provide dynamic emissivity estimates over land surfaces to support physical precipitation retrievals for GPM. The dynamic emissivity approaches include physical variables such as leaf area index and soil moisture as well as empirical combinations of channel brightness temperatures, including their time variations. These global emissivity estimates are to be integrated and tested within the GMI GPROF algorithm.

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Tao, Wei-Kuo Advancing the Retrieval of Latent Heating for PMM with Improved Simulations of Convective, Synoptic, and Cold Season Systems and their Associated Microphysical and Precipitation Processes

This work includes improving simulations/models for a wide range of precipitating cloud systems, from weak, unorganized isolated rain showers to intense mesoscale convective precipitation systems to large-scale synoptic snow storms, and their associated precipitation structures, latent heat release profiles and cloud microphysical processes.  Data from GPM field campaigns will be used to validate and improve the microphysical processes in the high-resolution numerical models.  Consequently, this work also expands and improves the performance of the Goddard Convective-Stratiform Heating (CSH) algorithm for the TRMM and GPM eras by using the improved model simulated latent heating, radiation and surface rain/snowfall data.

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PMM / GPM International Collaborator Team

Leveraging of GPM international partner research activities and infrastructure enables coordinated global precipitation remote sensing research and ground validation activities to be conducted. Here “global” refers to both geography and precipitation regime- enabling gap-filling observations and complementary research to more completely validate satellite observations around the globe. Within this framework specific collaborations between PMM Science Team investigators, GPM GV, and international partners have been sought. Currently active * collaborations are outlined in the below table.

Country Investigators Focus
Argentina P. Salio Ground validation of in a sub-tropical convective precipitation environment
Australia P. May, A. Protat Land/Sea-based direct GV, precipitation process studies and field measurements in the southern hemisphere tropics and mid-latitudes
Austria J., Fuchsberger, G. Kirchenghast, S. O Ground validation and rain variability in the mid-latitudes using the dense WegenerNet network
Belgium S. Lhermitte Snow process studies and measurement, Antarctica
Brazil L. Machado, D. Vila, C. Angelis Ground validation and storm system process studies in the tropics/sub-tropics, field measurements
Canada D. Hudak, P. Joe (WMO) Ground validation, snow process studies and field measurements in the mid and high-latitudes
European Union (ECMWF) P. Bauer, A. Geer GPM data for model data assimilation
Finland A.-M. Harri, D. Moisseev Ground validation, snow process studies and field measurements, High-Latitudes
France R. Roca, N. Viltard, F. Aires Megha Tropiques Mission, data and algorithms, global land surface emission (Aires)
Italy G. Pannegrossi, V. Levizzani (IPWG), L. Baldina, S. Puca, G. Vulpiani HSAF precipitation retrieval algorithms, ground-validation, GV radar calibration/measurement practices, mid-latitude Mediterranean region
Korea G. Ryu, G. Lee, S. Joo Ground validation, precipitation process studies and field measurement (rain, orographic snow), mid-latitudes land/sea.
Spain F. Tapiador Ground Validation, precipitation character and variability, field measurements, mid-latitudes
Switzerland A.    Berne Ground validation, precipitation field measurements, Alpine orographic snow processes, mid-latitudes
United Kingdom A.    Battaglia Active/passive radiative modeling, multiple scattering processes, field measurements, physical ground-validation

* Note: The formal list of collaborators is dynamic, often a function of partner funding status and guided research focus.