National Drought Mitigation Center


NDMC Climatologist Tsegaye Tadesse working with Mexico on a version of VegDRI

June 28, 2013

Mexico is working to implement drought monitoring that integrates climate, satellite and environmental information – an approach similar to the Vegetation Drought Response Index (VegDRI) developed through a partnership of the National Drought Mitigation Center and the U.S. Geological Survey’s Earth Resources Observation and Science (EROS) Center.

Tsegaye Tadesse, NDMC climatologist and remote sensing expert, and Jesslyn Brown, EROS geographer, traveled to Mexico City in April 2013 to work with Mexico’s Agricultural and Fisheries Information Service on how Mexico can implement its own version of VegDRI and to present at the XIII Agricultural Outlook Forum 2013. Brown and Tadesse developed the prototype VegDRI for the U.S. starting in 2002.

Decision-makers can use early warning of drought to help reduce its impacts, ranging from economic losses in developed countries to famine and mass migration in developing countries, Tadesse said in his presentation to the forum.

Tsegaye Tadesse, NDMC climatologist, center, with Jesslyn Brown, USGS EROS geographer, left, and their facilitator, right, in front of the Angel of Independence in Mexico City.

“We have to integrate climate, satellite, hydro-meteorological and environmental data to be most efficient and proactive with drought early warning,” Tadesse said. “For those countries like Mexico that don’t have enough networked weather stations, satellite data are very important. These data would help to fill the gap when there is no ground observation.”

In the United States, though it’s not perfect, climatologists and decision-makers benefit from automated, networked climate monitoring stations. The NDMC works with the High Plains Regional Climate Center to access network data.

One of the first steps in developing a Mexican version of VegDRI has involved scientists in Mexico assembling data on climate, soils and other related variables, Tadesse said. Researchers world-wide have free internet access to satellite data on vegetation conditions collected and distributed by U.S. agencies, such as EROS. Next, researchers will create a regression-tree model to integrate all the different data inputs, and will produce a Mexican version of VegDRI map that shows vegetation conditions. The final stage will be evaluating and adjusting the model based on ground observations such as crop yield. This could eventually lead to some predictive capability that will help in food security management.

Tadesse’s research focuses on developing the Vegetation Drought Outlook, or VegOut, which would build on the understanding developed through VegDRI to identify patterns in data and project them into the future. He added that models eventually need to take the changing climate into account, because the past is now less likely to be a guide to the future.

VegOut would be a predictive tool, building on the understanding developed through VegDRI. “VegDRI is essential because unless you know what’s happening now, it’s meaningless to talk about the future,” Tadesse said.

Tadesse and Brown also attended the XIII Agricultural Outlook Forum 2013, organized by SAGARPA, Mexico’s Secretariat of Agriculture, Livestock, Rural Development, Fisheries and Food. The presentations by Tadesse and Brown are available online.