A joint project of the California Department of Water Resources (CDWR), U.S. Department of Agriculture, U.S. Geological Survey, NASA Ames Research Center, and California State University, Monterey Bay (CSUMB) has demonstrated the feasibility of tracking the extent of fallowed land in the Central Valley of California using satellite imagery. Project partners are now working to establish an operational fallowed land monitoring service as part of a California drought early warning information system, a pilot of the National Integrated Drought Information System (NIDIS) led by NOAA. Supported by the NASA Applied Sciences Program and the NIDIS Program Office, the primary goal of the pilot project is to provide objective, accurate, and timely assessments of fallowed acreage to decision makers in California to support drought impact assessment and mitigation planning.
Geographic Focus
Central Valley of California
Application Readiness Level
ARL = 6
The project has demonstrated the feasibility of providing within season estimates of fallowed agricultural acreage and conducted field surveys and analyses of data provided by growers to quantify the accuracy of the new information products. The team has demonstrated that the information products meet the user requirements for accuracy and timeliness. The project team has been delivering monthly updates on land fallowing to the California Department of Water Resources since 2014 to support decision making for drought response and mitigation.
Principal Investigator
James Verdin, USGS/EROS
Project Team
Rick Mueller, USDA National Agricultural Statistics Service
Jeanine Jones, California Department of Water Resources
Forrest Melton, Lee Johnson, Carolyn Rosevelt, CSU Monterey Bay and NASA Ames Research Center
Rama Nemani, NASA Ames Research Center
John Dwyer, USGS/EROS
Collaborators & Stakeholders
NASA-Ames, USGS/EROS, CSUMB, USDA National Agricultural Statistics Service, California Department of Water Resources, USGS Flagstaff, US Bureau of Reclamation, California Farm Water Coalition, Western Growers Association, National Integrated Drought Information System (NIDIS)
Technical Overview
Shortage of water due to drought leads to an increase in the extent of fallowed land in the Central Valley because farmers are unable to fully irrigate crops, and will often prioritize use of the limited available agricultural water supplies to attempt to sustain perennial crops on their farms and ranches. When drought causes land to be taken out of production, farm income and agricultural input sales decrease, while unemployment increases among workers employed by farms and related businesses. Timely and accurate knowledge of the extent of fallowing can give vital insight into the severity of drought impacts, and provide the basis for sound decisions for drought response. Such decisions can ensure efficient allocation of scarce available water for on-farm use, and authorize provision of emergency assistance. The resulting disaster designations and emergency proclamations trigger loan and tax credit programs to help agricultural producers and businesses mitigate impacts on their operations, as well as social programs to aid farm worker households whose livelihoods are disrupted.
Despite the importance of this measure of drought impact, until now there has been no source of timely, comprehensive information on the extent of fallowed acreage during the growing season to support decision making, with official Cropland Data Layer data products from USDA not available until January of the following year.
The project partners have shown that the methods for producing the annual Cropland Data Layer (CDL) of the USDA National Agricultural Statistics Service (NASS), which includes a fallowed land class, can be modified and applied to support within-season mapping of fallowed agricultural lands. Furthermore, the project team has demonstrated how new methods using time-series of data on crop canopy development from NASA and USGS satellites (Terra, Aqua, and Landsat) can provide information on land fallowing and reductions in planted acreage early in the year. These imagery classifications provide the basis for monthly county tabulations, maps, and GIS files for fallowed land extent. This capability is now providing early identification of changes in fallowed acreage due to water shortage during drought, filling an important information gap and reducing ambiguity surrounding drought impact assessment and decision making for drought mitigation.
Additional Information
For more information and to download data and reports from this project, please see https://nex.nasa.gov/nex/projects/1372/.
Related Research Areas