Overview
We are very pleased to announce the launch of the WFP-VAM Data Visualization platform for monitoring the performance of the agricultural seasons.
This system will allow users to assess the performance of the current and past rainfall seasons, the timing and intensity of drier or wetter than average conditions and their impact on vegetation status at the subnational level for most countries.
Users can download time series datasets for a near-global set of administrative divisions, going back to 1981 for rainfall and 2002 for vegetation. The primary data sources are CHIRPS gridded rainfall dataset produced by the Climate Hazards Group at the University of California, Santa Barbara and the MODIS NDVI CMG data made available by NOAA-NASA.
Data Coverage:
Data coverage is limited to countries within 50N to 50S. Countries which extend beyond these geographical limits will be partially included up to those limits. Hence a rainfall plot for the Russian Federation will refer only to the part of the country south of 50N. At the subnational level, only the administrative divisions which are fully contained within those limits, have data to display.
Data Sources
Rainfall:
Rainfall data is derived from the CHIRPS rainfall estimate, produced by the Climate
Hazards Group, at the University of California, Santa Barbara. CHIRPS stands for
Climate Hazards Group InfraRed
Precipitation with Station data.
CHIRPS is a 35+ year quasi-global rainfall dataset. Spanning 50°S-50°N (and all
longitudes), starting in
1981 to near-present, CHIRPS incorporates 0.05° resolution satellite imagery with
in-situ station data
to create gridded rainfall time series for trend analysis and seasonal drought monitoring.
CHIRPS
data is available at 5 and 10 day accumulations. CHIRPS is free to use and easily
accessible at:http://chg.geog.ucsb.edu/data/chirps/
Full details on the underlying methodology can be found in:
Funk, Chris, Pete Peterson, Martin Landsfeld, Diego Pedreros, James Verdin, Shraddhanand
Shukla,
Gregory Husak, James Rowland, Laura Harrison, Andrew Hoell & Joel Michaelsen.
"The climate
hazards infrared precipitation with stations—a new environmental record for monitoring
extremes".
Scientific Data 2, 150066. doi:10.1038/sdata.2015.66 2015.
NDVI:
The NDVI data in use is from the MODIS platforms Terra and Aqua, which provide global
coverage since 2000 (Terra) and mid-2002 (Aqua) at about 5Km resolution with a temporal
frequency of
overlapping 16 day periods. The MODIS NDVI CMG data product was retrieved from REVERB,
courtesy of:
- NASA EOSDIS Land Processes Distributed Active Archive Center (LP DAAC)
- USGS/Earth Resources Observation and Science (EROS) Center
- Sioux Falls, South Dakota, USA
http://reverb.earthdata.nasa.gov
Product codes are: MOD13C1 (Terra) and MYD13C1 (Aqua)
Earth Observing System ClearingHOuse (ECHO) / Reverb, Version 10.X
Greenbelt, MD: EOSDIS, Goddard Space Flight Center (GSFC) National Aeronautics and
Space Administration (NASA)
Administrative Divisions: