Using satellite data to protect crops

By Andi Anderson

As drought continues to impact crop yields in the western United States, technology plays a vital role in tracking crop health and securing food supplies.

Using satellite data, scientists from NASA and NOAA have developed the Vegetation Health Index (VHI), which provides accurate crop health maps across the globe.

This index is especially valuable for monitoring weather effects on crops and helping to predict yields, impacting food security and market prices worldwide.

The VHI combines data on visible and near-infrared light, captured by the JPSS satellites, to measure crop health. Developed by NOAA scientist Dr. Felix Kogan, the VHI has become a crucial tool, informing farmers, governments, and food security agencies.

The color-coded maps show green for healthy growth and red for stressed vegetation, helping identify drought-affected areas. This data influences decisions on planting, food prices, and exports, as noted by USDA meteorologist Mark Brusberg.

This technology dates back to 1972, when a sudden grain shortage caused by Soviet Union purchases highlighted the need for global crop monitoring. NASA responded by launching the Landsat 1 satellite, which provided a new view of agricultural conditions from space.

This event led to a partnership with USDA and NOAA, creating the Large Area Crop Inventory Experiment (LACIE), the first satellite crop production forecast program.

Today, advanced satellite tools like the VHI continue to play a key role. They allow scientists to monitor crops through various growth stages, using formulas like the Normalized Difference Vegetation Index (NDVI) to measure vegetation health.

By incorporating temperature data, the VHI gives a more comprehensive view of crop conditions, especially under extreme weather. It enables the USDA to predict crop yields in over 120 regions, informing the World Agricultural Supply and Demand Estimates report, a vital tool for global markets.

Satellite crop monitoring technology has become essential for global food security, helping avoid crises like the "Great Grain Robbery" of the 1970s. Through ongoing partnerships, NASA and NOAA ensure accurate crop data, supporting both U.S. and international agriculture.