PRECIPITATION MEASUREMENT MISSIONS

Ground Validation observations for statistical validation of GPM products are made in a series of investigator-led field measurement campaigns, known as Extended Observation Periods (EOPs). EOPs last several months and are punctuated by one or more Intensive Observation Periods (IOPs).

Upcoming Field Campaigns

• An integrated meteorological/hydrological campaign is scheduled for the spring/summer of 2013. This campaign will be conducted in coordination with NOAA's Hyrometeorological Testbed (HMT) and will be conducted in the Tar/Neuse River Basin in North Carolina.
• Two additional field campaigns are planned for the GPM post-launch era. These campaigns will help to validate the GPM precipitation products. One campaign is planned for 2015, and a final campaign is planned for 2016.

Completed Field Campaigns

• GPM Cold-season Precipitation Experiment (GCPEX) was conducted in cooperation with Environment Canada and NASA's CloudSat mission from January 17 through February 29, 2012. The experiment used instrumented NASA DC-8 and NASA-funded University of North Dakota Cessna Citation aircraft for flights over ground sites located in and around the Environment Centre for Atmospheric Research Experiments (CARE) located in Egbert, Ontario. The DC-8 aircraft flew high above clouds and precipitation with instruments similar to those on the GPM Core satellite. The Citation aircraft flew through snowing clouds to measure snowflake properties in situ. Ground-based equipment was also be used to measure precipitation. Data from the experiment will be used to develop and validate snow and frozen precipitation retrieval algorithms used in the generation of data products for GPM, CloudSat and future polar precipitation missions planned by the European Union.
• MC3E: The Mid-latitude Continental Convective Clouds Experiment took place in the spring of 2011. This campaign was conducted in cooperation with the Department of Energy's (DoE) Atmospheric Radiation Program (ARM). The field campaign occurred in south-central Oklahoma and sampled a broad variety of precipitation types and intensities, including many cases of severe thunderstorm systems, using two aircraft (NASA/ER-2 and UND/Citation) and an extensive array of ground instruments over a 6-week period. The campaign contributed to the improvement of radar and microwave precipitation retrieval algorithms over land. [MC3E Science Plan]
• LPVEx: GPM GV participated in the fall 2010 Light Precipitation Verification Experiment (LPVEx) hosted by the Finnish National Meteorological Institute (FNMI). The CloudSat project led the overall coordination of the LPVEx field campaign including the planning, execution, and subsequent analysis and archival of results. GPM led the installation and operation of numerous additional ground assets including rain gauges and disdrometers to augment and extend the volumetric use of existing in situ rainfall sensors on the ground. Other collaborators include Environment Canada, the United Kingdom National Environmental Research Council, Vaisala Inc. and the University of Helsinki. For more information, visit the LPVEx Campaign Homepage at CSU. [LPVEx Science Plan]
• CHUVA and Pre-CHUVA:  A collaboration with the Brazilian space program, this project carries out field experiments at seven sites to investigate the different precipitation regimes in Brazil. To study these precipitation regimes, the field campaigns make use of dual polarization radar, lidar, microwave radiometers, disdrometer, radiosonde and various other instruments. The analysis is performed focusing on the microphysical evolution and cloud life cycle, different precipitation estimation algorithms, the development of thunderstorms and lightning formation, processes in the boundary layer and cloud microphysical modeling. This project extends the knowledge of cloud processes to reduce uncertainties in precipitation estimation, mainly from warm clouds and, consequently, improving knowledge of the water and energy budget and cloud microphysics.
• C3VP: GPM GV participated in the winter 2007/2008 Canadian CloudSat/CALIPSO Validation Programme (C3VP) hosted by Environment Canada at the Meteorological Service of Canada's Centre for Atmospheric Research Experiments (CARE). More information can be found at the official C3VP website.