Climatologists to Farmers: Watch for La Niña

Farmers, watch for La Niña. That’s the advice of the Southeast Climate Consortium, as well as state climatologists in Alabama, Florida and Georgia. A watch means that conditions are likely for the development of a full-fledged La Niña event.

The watch will be followed by an official La Niña declaration if development follows over the next one to three months.

What exactly does this mean in terms of farmers? Climatologists say that La Niña conditions usually bring a warmer and drier cool season (October through March) to Florida, central and southern Alabama, and central and south Georgia.

One farm expert urges farmers to heed the advice of the proverbial summer ant and prepare now for what may come later.

“They need to keep up with conditions as things progress because of the changes that could follow,” says Jim Novak, an Alabama Cooperative Extension System economist and Auburn University professor of agricultural economics.

“They need to make hay while the sun shines, or, in this case, while the water lasts.”

The tropical Pacific Ocean is now poised to develop into a full-fledged La Niña. In fact, experts say chances are good that La Niña conditions will develop, strengthen and persist through the fall and winter months. Months of cooler-than-normal temperatures already have occurred near the South American coast.

La Niña typically is thought of as the opposite of El Niño. Under La Niña conditions, sea surface temperatures along the equator in the eastern and central Pacific Ocean are a few degrees colder than normal for a minimum of five months. La Niña typically returns every two to seven years.

Undoubtedly, for many drought-stressed Alabama farmers, the news can’t get much worse. Indeed, with the arrival of La Niña, there is a good chance that drought conditions, currently ranging from exceptional across much of Alabama, may get even worse into next spring.

There also could be an effect on cooler season moisture recharge — a factor Southeastern farming depends on during cooler months. If below-normal rainfall occurs from October to March, moisture recharge of groundwater, soils, ponds and reservoirs will be limited.

Farmers who intend to plant winter forage and do not irrigate may be especially hard pressed.

A La Niña effect also would raise the specter of wildfires in the southern tier of the state.

The Consortium has estimated the probability of normal or above normal rainfall for central Florida in January 2008 is only 8 percent, while the chance of very dry conditions (less than half of normal rainfall) is 72 percent.

The news is better for the Panhandle of Florida, south Georgia and south Alabama. Climatologists estimate the probability of normal or above-normal rainfall in January 2008 is 20 percent, for moderately dry 50 percent, and for very dry 30 percent.

Posted by Jim Langcuster at September 11, 2007 04:10 PM