Agri Leader

UF scientist develops new drought index

Scientists at the University of Florida’s Institute of Food and Agricultural Sciences (IFAS) have developed a new tool, dubbed ARID for Agricultural Reference Index for Drought, that can help farmers mitigate costly droughts.

ARID, which researchers showed could predict drought levels for crops on farms in Florida and Georgia, can now deliver much wider impact for growers, the researchers said.

It’s intended to help farmers plant at optimal times and avoid crop-destroying drought, which can cost millions of dollars in a given year, according to Keith Ingram, a former associate scientist in UF/IFAS’s agricultural and biological engineering department and former director of the Southeast Climate Consortium who led the ARID project. He recently joined candy manufacturer Mars Inc. as agronomy cacao research manager.

If growers know when their crops will need the most water, Ingram said, they can plant accordingly and lessen the threat of drought. Improving such a capability can help growers reduce the economic impact of droughts, which the National Climactic Data Center estimated at $30 billion during the nationwide heat wave and drought of 2012.

ARID researchers used the tool to predict crop yields by quantifying water loss for cotton, soybeans, corn and peanuts on eight farms in Florida and Georgia. They looked at 134 years of daily weather data from the farms and found ARID can reasonably predict the drought levels of crops.

Although other drought models have been developed in the past, “ARID is the first one that really builds on the physiology of a crop in a way that allows us to take a generic crop and apply it to a wide range of other crops,” Ingram said.

The generic crop is a grass.

“The reason we used grass is that it grows year-round,” Ingram said. “Not all crops do. So we needed an index we could use to estimate year-round. So if there’s a drought during the winter, we can use the grass to estimate and apply data to a crop that grows during the winter, like tomatoes or winter wheat. During the spring, we can use it on soybeans or corn.”

In Florida, droughts occur on average one out of every three years, Ingram said. “That can mean two years in a row out of six or three years in a row out of nine.”

Northern Florida suffered a fairly severe drought in 2010-11. The last one before that was in 2006.

Ingram cited the current and catastrophic drought in California, partly a result of the state’s population explosion, as a likely harbinger of Florida’s future. “The same thing is going to happen here some day,” he said, “because there is so much pumping from ground water that at some point there is going to be competition between the developed areas -- with municipal and home water use -- and agriculture.”

The ARID model, however, will enhance capabilities for water management that can help mitigate even a severe drought for farmers.

An ARID tool is now available to growers on the website published by the Southeast Climate Consortium. “It provides estimates for different areas of Florida, so farmers can track the status of drought for how it relates to their crops,” Ingram said, adding the next step is to develop the tool into an actual forecast. “Right now, it’s just monitoring the situation,” he said.

UF extension offices and agents will play a key role in educating and engaging farmers through local extension agents.

“The significance of Keith’s work is that it helps in the mission to use research and innovation to provide a solution for the impact of drought,” said Brenda Ortiz, an associate professor at Auburn University and an extension specialist for Southeast Climate Consortium. “And a drought index itself is becoming more and more important because in the Southeast, the soils are light in texture, so they are more prone to drought. And certain weather conditions make the risk of drought even worse. So we needed a better tool to be able to see how drought conditions are changing. And it can be used as a planning and risk management tool by growers.”

Ortiz is now working to help the extension office system roll out the model and ARID tool to farmers in the region, including Florida.

ARID represents a significant step forward in drought mitigation, Ingram said. “Farmers are always looking for new ways to manage drought. And, of course, irrigation is the best thing. But because water is a scarce resource, we need to manage it more efficiently.”