Computer Model May Give Farmers The Edge On The Next El Niño

March 13, 1998

GAINESVILLE — Drowned potato plants, rows of buckled corn stalks, ruined cabbage fields: El Niño’s torrential rains and powerful storms have hurt Florida vegetable farmers this year.

But they may be able to limit damage from future El Niños, thanks to computer crop models being developed by a team of researchers from three state universities.

The researchers intend to use the models — as well as historical information on crop yields and prices — to help farmers pick what crops to plant, when to plant and how to manage crops months before El Niños or related La Niña events strike. The result for consumers could be less fluctuation in prices despite wildly unusual weather.

“If the climate forecasters can predict an El Niño three to six months ahead of time, then agriculture decisions might be changed to take advantage of that situation and reduce risks and uncertainties,” said Jim Jones, an agricultural and biological engineering professor at the University of Florida.

Caused by a pool of unusually warm water in the Pacific, El Niños bring wet, stormy weather to California and the South. La Niñas, the system’s lesser-known twin, are cold-water phenomenons that bring unusually dry weather.

Supported by the National Oceanographic and Atmospheric Administration (NOAA) and the National Science Foundation, researchers at UF, Florida State University and the University of Miami began the project last year. An initial step was to gauge how past El Niños or La Niñas have affected crops in Florida and the Southeast, Jones said.

Jim Hansen, a researcher at UF, scrutinized records back to 1929 to measure how past El Niños and La Niñas have swayed vegetables, sugar cane and citrus yields in Florida. He also studied the systems’ impact on peanuts, tomatoes, cotton, tobacco, field corn and soybeans in Florida, Alabama, Georgia and South Carolina.

The good news is, some crops were untouched. Florida’s orange harvest, for example, did not vary significantly in the years following La Niñas or El Niños. Orange trees flower in winter, so the weather systems, which have a pronounced effect in winter, might be expected to hurt harvests the year after they occur.

Other crops, however, were greatly affected. Yields of tomatoes, bell peppers, sweet corn and snap beans plunged during the winter harvest in Florida in El Niño years, Hansen found. Yields of bell peppers sank 31 percent below the long-term average, while yields for sweet corn sank 27 percent. A likely cause is excessive rainfall, which can encourage disease by saturating plants while blocking sunlight, Hansen said.

The plunge in vegetable yields was accompanied by increases in prices paid to farmers, Hansen found. Prices for bell peppers, for example, were 31 percent higher, while snap beans were 21 percent higher. While he did not research prices at the produce stand, they would likely have increased as well, he said.

This winter growing season is not over, but cabbage, potato and corn farmers already are reporting damaged crops. Up to 30 percent of Florida’s winter vegetable crops are at risk, according to published reports.

The computer models can combine weather and soil information with virtual farming decisions to predict growth and yield for crops, Jones said.

“It takes maybe a second or less to grow crops on the PC’s, so we grow many, many crops to look at the probabilities under different weather predictions…then we can change management practices to see what effect that will have,” Jones said.

While the idea is to give farmers the information they need to map out a growing strategy tailored to the characteristics of a predicted El Niño or La Niña, deciding that strategy is not as clear-cut as it might appear, Jones said.

Noting that a coming El Niño could hurt a crop, farmers may chose to plant other crops, but they may also do the opposite. If, for example, they know tomatoes are likely to be hit hard, they may plant more than usual, speculating prices will go up.

NOAA is the chief sponsor of the project, contributing more than $850,000 last year and this year, part of it for a similar project in Argentina and Uruguay. The universities are seeking an additional $450,000 annually from the organization to continue the work in the next three years.