The document categorizes and describes various ground station, gridded, satellite, and radar datasets for precipitation data. It provides information on the resolution, domain, parameters, methodology, time period, and measurement frequency for numerous datasets from sources like USGS, NOAA, PRISM, TRMM, GPM, and NEXRAD radar.

1. Precipitation Data

2. Categories
 Ground Station - Precipitation Datasets
 United States Geological Survey
 National Oceanic & Atmospheric Administration (National Climatic Data Center)
 Georgia Automated Environmental Monitoring Network (GAEMN)
 Georgia Forestry Commission
 Community Collaborative Rain, Hail & Snow Network
 GHCN (Global Historical Climatology Network)
 Gridded - Precipitation Datasets
 PRISM (Parameter-Elevation Relationships on Independent Slopes Model)
 GPCC (Global Precipitation Climatology Centre)
 CRU (Climate Research Unit Time Series)
 PRECipitation REConstruction over Land (PREC/L)
 CPC (Climate Prediction Center) Unified Gauge-Based Analysis of Global Daily
Precipitation
 MSU (Microwave Sounding Unit)
 University of Delaware

3. Categories
 Satellite - Precipitation Datasets
 TRMM (Tropical Rainfall Measuring Mission)
 Global Precipitation Measurement Mission (GPMM)
 PERSIANN (Precipitation Estimation from Remotely Sensed
Information using Artificial Neural Networks)
 CMORPH (CPC Morphing Technique)
 CMAP (CPC Merged Analysis of Precipitation)
 GPCP (Global Precipitation Climatology Project)
 Radar - Precipitation Datasets
 NEXRAD (Next Generation Weather Radar)

4. Measurement Frequency Classification
NRT 15 Minute Hourly Daily Monthly Yearly
Ground Stations - USGS, NOAA,
USGS, NOAA,
GFC,
USGS, NOAA,
GAEMN
USGS, NOAA,
GHCN
USGS, NOAA,
Gridded - - -
PRISM, CPC,
MSU
PRISM, GPCC,
CRU, PREC/L,
CPC, MSU, UoD
PRISM
Satellite
GPMM, TRMM,
PERSIANN,
CMORPH
- - - CMAP, GPCP -
Radar NEXRAD - - - - -

5. Ground Stations
United States Geological Survey
 http://waterdata.usgs.gov/ga/nwis/current/?type=precip&grou
p_key=county_cd
 Grid Size – Point Data (287 Stations)
 Domain – Georgia, USA
 Available Parameters – Gage Height, Precipitation,
Temperature, Dissolved Oxygen, pH, Turbidity, Specific
Conductance
 Methodology – Rain gages such as the non-recording
cylindrical container type or the recording weighing type, float
type and tipping-bucket type
 Time Period – 2007 - 2015
 Measurement Frequency – 15 Minute, Hourly, Daily,
Monthly, Annual

6. Ground Stations
National Oceanic & Atmospheric Administration
(National Climatic Data Center)
 http://www.ncdc.noaa.gov/cdo-web/datasets
 Grid Size – Point Data (68 Stations) (2% Coverage¹)
 Domain – Georgia, USA
 Available Parameters – Precipitation
 Methodology – An inlet-heated, wind-shielded weighing rain
gauge (configured with three load cell sensors), precipitation
(wetness) detector, and an auxiliary tipping bucket gauge.
 Time Period – 1971 - 2014
 Measurement Frequency – 15 Minute, Hourly, Daily,
Monthly, Annual (Dataset maybe delayed 6 months or more)
¹Coverage is an approximation of total completeness based on the
most complete data element, and the overall data range.

7. Ground Stations
Georgia Automated Environmental Monitoring Network
(GAEMN)
 http://weather.uga.edu/aemn/cgi-bin/AEMN.pl?site=GAAA
 Grid Size – Point Data (52 Stations)
 Domain – Georgia, USA
 Available Parameters – Air Temperature, Relative Humidity,
Rainfall, Solar Radiation, Wind Speed, Wind Direction, Soil
Temperature
 Methodology – Automated Weather Station
 Time Period – 2000 - 2015
 Measurement Frequency – Daily

8. Ground Stations
Georgia Forestry Commission (GFC)
 http://weather.gfc.state.ga.us/climate/climate.aspx
 Grid Size – Point Data (18 Stations)
 Domain – Georgia, USA
 Available Parameters – Air temperature, Relative Humidity,
Wind Direction, Wind Speed, Soil Temperatures
 Methodology – Automated Weather Station
 Time Period – 1998 - 2015
 Measurement Frequency – Hourly

9. Ground Stations
Community Collaborative Rain, Hail & Snow Network
 http://www.cocorahs.org/ViewData/ListMultiDayPrecipReports
.aspx
 Grid Size – Point Data (1163 Stations)
 Domain – Georgia, USA
 Available Parameters – Cumulative Precipitation
 Methodology – Standard 4-Inch Diameter Rain Gauge
 Time Period – 2000 - 2015
 Measurement Frequency – Irregular

10. Ground Stations
GHCN (Global Historical Climatology Network)
 http://gis.ncdc.noaa.gov/map/viewer/#app=cdo&cfg=cdo&theme=precip&la
yers=01&node=gis
 Grid Size – Point Data
 Domain - Global
 Available Parameters – Precipitation
 Methodology – The database was created from 15 source data sets,
including:
 The National Climatic Data Center's (NCDC's) World Weather Records
 CAC's Climate Anomaly Monitoring System (CAMS)
 NCAR's World Monthly Surface Station Climatology
 CIRES' (Eischeid/Diaz) Global precipitation data set
 P. Jones' Temperature data base for the world
 S. Nicholson's African precipitation data base
 Time Period – Variable (1697 - 1990)
 Measurement Frequency – Monthly

11. Gridded Datasets
PRISM (Parameter-Elevation Relationships on Independent
Slopes Model) - Christopher Daly and Kirk Bryant
 http://www.prism.oregonstate.edu/explorer/
 Grid Size – Climatologies (normals) are available at 30-arcsec (800
meters) and monthly data are available at 2.5 arcmin (4 km)
resolution.
 Domain – Contiguous US
 Main Variables – Dew Point Temperature, Max. & Min. Air
Temperature, Precipitation
 Methodology – The PRISM products use a weighted regression
scheme to account for complex climate regimes associated with
orography, rain shadows, temperature inversions, slope aspect,
coastal proximity, and other factors.
 Time Period – 1895 - Present
 Measurement Frequency – Daily, Monthly, Annual, 30-year
normals (1981-2010) (monthly and annual)

12. Gridded Datasets
GPCC (Global Precipitation Climatology Centre)
 http://www.esrl.noaa.gov/psd/data/gridded/data.gpcc.html
 Grid Size –
 0.5 degree latitude x 0.5 degree longitude global grid
 1.0 degree latitude x 1.0 degree longitude global grid
 2.5 degree latitude x 2.5 degree longitude global grid
 Domain - Global
 Available Parameters – Precipitation
 Methodology – Based on quality-controlled data from 67,200
stations world-wide that feature record durations of 10 years or
longer.
 Time Period – 1901 - 2010
 Measurement Frequency – Monthly

13. Gridded Datasets
CRU (Climate Research Unit Time Series)
 http://catalogue.ceda.ac.uk/uuid/4a6d071383976a5fb24b5b42e28cf
28f
 Grid Size – 0.5 degree latitude x 0.5 degree longitude global grid
(4,000 Stations)
 Domain - Global
 Available Parameters – Cloud cover, diurnal temperature range,
frost day frequency, precipitation, daily mean temperature, monthly
average daily maximum temperature, vapor pressure, Potential
Evapo-transpiration and wet day frequency.
 Methodology – Based on an archive of monthly mean
temperatures provided by more than 4000 weather stations
distributed around the world.
 Time Period – 1901 - 2013
 Measurement Spacing – Monthly

14. Gridded Datasets
PRECipitation REConstruction over Land (PREC/L)
 http://www.esrl.noaa.gov/psd/data/gridded/data.precl.html
 Grid Size – (17,000 Stations)
 0.5 degree latitude x 0.5 degree longitude global grid
 1.0 degree latitude x 1.0 degree longitude global grid
 2.5 degree latitude x 2.5 degree longitude global grid
 Domain - Global
 Available Parameters – Precipitation
 Methodology – Precipitation gauge measurements over land from
the GHCN-v2 (Global Historical Climatology Network version 2) are
interpolated
 Time Period – 1948 – Present (Except 0.5 degree data, which runs
behind)
 Measurement Frequency – Monthly

15. Gridded Datasets
CPC (Climate Prediction Center) Unified Gauge-Based
Analysis of Global Daily Precipitation
 http://www.esrl.noaa.gov/psd/data/gridded/data.unified.daily.c
onus.html
 Grid Size – 0.25 degree latitude x 0.25 degree longitude global
grid (30,000 Stations)
 Domain - Global
 Available Parameters – Precipitation
 Methodology – This dataset has two components: (a) the
"retrospective version" which uses 30K stations and spans 1979-
2005 and (b) the "real-time version" which uses 17K stations and
spans 2006-present.
 Time Period – 1948 – 2006 (Daily), 1948 – Present (Monthly)
 Measurement Frequency – Daily, Monthly

16. Gridded Datasets
MSU (Microwave Sounding Unit)
 http://www.esrl.noaa.gov/psd/data/gridded/data.msu.html
 Resolution – 2.5 degree latitude x 2.5 degree longitude global
grid
 Domain - Global
 Available Parameters – Precipitation, Temperature
 Methodology – The NOAA satellites contributing to this
dataset are, in order of their launch, TIROS-N, NOAA-6, -7, -9, -
10,-11, and NOAA-12.
 Time Period – 1979 – 1996
 Measurement Frequency – Daily, Monthly

17. Gridded Datasets
University of Delaware (UoD)
 http://www.esrl.noaa.gov/psd/data/gridded/data.UDel_AirT_P
recip.html
 Resolution – 0.5 degree latitude x 0.5 degree longitude global
grid
 Domain - Global
 Available Parameters – Precipitation, Temperature
 Methodology - Cort Willmott & Kenji Matsuura of the
University of Delaware have put data together from a large
number of stations, both from the GHCN2 (Global Historical
Climate Network) and, more extensively, from the archive of
Legates & Willmott.
 Time Period – 1901 – 2010
 Measurement Frequency – Monthly

18. Satellite Datasets
TRMM (Tropical Rainfall Measuring Mission)
 http://trmm.gsfc.nasa.gov/
 Resolution - 0.25 degree latitude x 0.25 degree longitude global
grid
 Domain - Global
 Available Parameters – Precipitation
 Methodology – The mission uses 5 instruments: Precipitation
Radar (PR), TRMM Microwave Imager (TMI), Visible Infrared
Scanner (VIRS), Clouds & Earths Radiant Energy System
(CERES) and Lightning Imaging Sensor (LSI).
 Time Period – 1997 – (March) 2015
 Measurement Frequency – 3 Hour (Near Real Time)

19. Satellite Datasets
Global Precipitation Measurement Mission (GPMM)
 http://pmm.nasa.gov/data-access/downloads/gpm
 Resolution - 0.1 degree latitude x 0.1 degree longitude global
grid
 Domain - Global
 Available Parameters – Precipitation
 Methodology – The satellite carries a microwave imager. Its
scanning antenna rotates 32 times per minute, while a downward
pointing detector reads microwaves reflected from the
atmosphere below. As it orbits, GPM scans the Earth’s
atmosphere with its Dual-Frequency Precipitation Radar. The
radar scans in two frequencies, the Ku scan (13.6 gigahertz) and
the Ka scan (35.5 gigahertz).
 Time Period – (March) 2014 - Present
 Measurement Frequency – 3 Hour (Near Real Time)

20. Satellite Datasets
PERSIANN (Precipitation Estimation from Remotely
Sensed Information using Artificial Neural Networks)
 http://chrs.web.uci.edu/persiann/
 Resolution – 0.25 degree latitude x 0.25 degree longitude
global grid
 Domain - Global
 Available Parameters – Precipitation, Atmosphere
 Methodology – The PERSIANN algorithm used here is based
on the geostationary longwave infrared imagery to generate
global rainfall.
 Time Period – 1979 - Present
 Measurement Frequency – 3 Hour (Near Real Time)

21. Satellite Datasets
CMORPH (CPC Morphing Technique)
 http://www.cpc.ncep.noaa.gov/products/janowiak/cmorph_des
cription.html
 Resolution – 0.25 degree latitude x 0.25 degree longitude
global grid
 Domain - Global
 Available Parameters – Precipitation, Atmosphere
 Methodology – The precipitation estimates derived from the
passive microwaves aboard the DMSP 13, 14 & 15 (SSM/I), the
NOAA-15, 16, 17 & 18 (AMSU-B), and AMSR-E and TMI aboard
NASA's Aqua and TRMM spacecraft, respectively.
 Time Period – 2002 - 2013
 Measurement Frequency – 3 Hour, Daily (Near Real Time)

22. Satellite Datasets
CMAP (CPC Merged Analysis of Precipitation)
 http://www.esrl.noaa.gov/psd/data/gridded/data.cmap.html
 Resolution – 2.5 degree latitude x 2.5 degree longitude global
grid
 Domain - Global
 Available Parameters – Precipitation, Atmosphere
 Methodology – Inputs are derived from gauge analysis;
microwave and infrared observations from polar orbiting and
geostationary satellites
 Time Period – 1979 - 2011
 Measurement Frequency – Monthly Mean

23. Satellite Datasets
GPCP (Global Precipitation Climatology Project)
 http://www.esrl.noaa.gov/psd/data/gridded/data.gpcp.html
 Resolution – 2.5 degree latitude x 2.5 degree longitude global grid
 Domain - Global
 Available Parameters – Precipitation, Atmosphere
 Methodology –
 The Version 2 Data Set contains data from several contributing centers:
 GPCP Polar Satellite Precipitation Data Centre - Emission (SSM/I emission estimates)
 F17 SSMIS: calibrating microwave data source to replace the F13 SSM/I, which failed in
September 2009
 GPCP Polar Satellite Precipitation Data Centre - Scattering (SSM/I scattering estimates)
 GPCP Geostationary Satellite Precipitation Data Centre (GPI and OPI estimates and rain
gauge analyses)
 NASA/GSFC Satellite Applications Office (TOVS estimates)
 GPCP Global Precipitation Climatology Centre (rain gauge analyses)
 Time Period – 1979 – (February) 2015
 Measurement Frequency – Monthly Mean

24. Radar
NEXRAD (Next Generation Weather Radar)
 http://www.ncdc.noaa.gov/nexradinv/
 Domain - US
 Available Parameters – Precipitation
 Methodology – NEXRAD (Next Generation Radar) currently
comprises 159 sites throughout the United States and select
overseas locations.
 Time Period – 1991 - 2015
 Measurement Frequency – Near Real Time
TDWR – Terminal Doppler Weather Radar

25. Data Sources
 PSD Gridded Climate Datasets: All
http://www.esrl.noaa.gov/psd/data/gridded/
 NCAR UCAR Climate Data Guide
https://climatedataguide.ucar.edu/