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Metadata Updated: December 7, 2023

The GPM Ground Validation Autonomous Parsivel Unit (APU) GCPEx dataset was collected by the Autonomous Parsivel Unit (APU), which is an optical disdrometer that measures the size and fall velocity of single precipitation particles. The APU consists of the Parsivel (the precipitation measuring instrument), developed by OTT in Germany, and its support systems, which were designed and built by the University of Alabama in Huntsville. The GPM Cold-season Precipitation Experiment (GCPEx) addressed shortcomings in the GPM snowfall retrieval algorithm by collecting microphysical properties, associated remote sensing observations, and coordinated model simulations of precipitating snow. These data sets were collected to aid in the achievement of the over arching goal of GCPEx which is to characterize the ability of multi-frequency active and passive microwave sensors to detect and estimate falling snow. The APU dataset for GCPEx provides precipitation data including raindrop size, raindrop counts, precipitation drop size, precipitation rate, precipitation amount, and snowflake size, counts and distribution. The GCPEx APU data was collected from several sites in Canada during the Winter 2011-2012 period.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources


Metadata Created Date December 1, 2022
Metadata Updated Date December 7, 2023

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date December 1, 2022
Metadata Updated Date December 7, 2023
Identifier C1979657178-GHRC_DAAC
Data First Published 2013-04-16
Language en-US
Data Last Modified 2022-05-09
Category GCPEx, geospatial
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Citation Petersen, Walter A, Ali Tokay, Patrick N Gatlin and Matthew T. Wingo.2013. GPM GROUND VALIDATION AUTONOMOUS PARSIVEL UNIT (APU) GCPEX indicate subset used. Dataset available online from the NASA Global Hydrometeorology Resource Center DAAC, Huntsville, Alabama, U.S.A. DOI:
Harvest Object Id d05ff82a-a4f1-4fa7-a086-39905737e2fb
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Metadata Type geospatial
Old Spatial -79.9279 44.1765 -79.6403 44.6862
Program Code 026:001
Source Datajson Identifier True
Source Hash 397bcf830ccbbcbb93277c67461161146b86ead14adb991c9b79a43227a277cf
Source Schema Version 1.1
Temporal 2011-10-26T20:22:00Z/2012-03-10T23:59:50Z

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