WASHINGTON — The USDA’s National Agricultural Statistics Service has announced the launch of a new satellite-based U.S. crop condition service named VegScape.
Like the popular CropScape geospatial product, VegScape delivers interactive vegetation indices so that Web users can explore, visualize, query and disseminate current vegetative cover maps and data without the need for specialized expertise, software or high end computers.
The agricultural community, policymakers, researchers and others now have a tool for policy decisions, scientific inquiry and educational efforts.
New satellite-based data are loaded on a weekly basis during the growing season. One can compare year-to-year change for 12 years, compare conditions at a given time to mean, median and ratio vegetative cover over the 12-year span and overlay a crop mask to help identify cropland versus noncropland, among many functions.
When viewing the maps, in most cases the deeper the green color the stronger the plant vigor while yellow/brown indicates poorer conditions.
Vegetation indices, such as the Normalized Difference Vegetation Index, and mean, median and ratio comparisons to prior years have proved useful for assessing crop conditions and identifying the land area affected by floods, drought, major weather anomalies and vulnerabilities of early/late season crops.
Additionally, the National Aeronautics Space Administration’s MODIS satellite that NASS uses for this project provides imaging at 250 meter (15 acres) per pixel resolution and 12 years of data history.
The high quality spatial information and daily satellite overpasses deliver detailed timely crop-specific condition information. Additionally, the data can be directly exported to Google Earth for mashups or delivered to other applications via Web services.
In addition to the new VegScape product, NASS released the 2012 Cropland Data Layer on Jan. 31 on its CropScape geospatial portal. The newly released 2012 CDL product depicts agricultural land cover over the continental United States at 30 meters resolution.
Both CropScape and VegScape provide free and open access to digital geospatial data layers using open geospatial standards, thereby supporting transparent and collaborative government initiatives.
NASS developed both services in cooperation with the Center for Spatial Information Science and Systems, George Mason University, Fairfax, Va.
Source: American Association for the Advancement of Science.