January 1998

Effects of El Nino and ice storm make winter interesting in U.S., world


The prophecies of the El Nino doomsayers have not yet come to pass, but the weather pattern has been exhibiting some effects on the nation.

Before real winter made its reappearance in the first full week of January, the Great Lakes region was basking in mid-50 temperatures and setting records in the process. Some of that very warm and moist air had its origins in the tropics and was at least indirectly related to abnormally warm ocean water in the eastern Pacific, the hallmark of an El Nino pattern.

Much of the Gulf Coast has seen abnormally heavy rains, including some flooding. Temperatures have been well above normal in the northern Great Plains. The California coast was expected to be pounded with a series of storms but has had just one major outbreak of bad weather in December. Predictions of beach erosion, landslides and massive flooding are so far not coming to pass.

The worst early winter weather has been in the northeastern U.S. and eastern Canada where a devastating ice storm knocked power to millions of people and thousands of businesses, including apple storage facilities.

Other parts of the world are showing stronger evidence of El Nino's darker side. Drought has struck portions of southeast Asia and the Philippines, which is having negative impacts on agriculture there. Sections of South America are seeing wetter than normal conditions while drought is developing in parts of South Africa.

"No single event usually has all the characteristics of an El Nino," said Jeff Andresen, agricultural meteorologist at Michigan State University.

Agricultural impacts of El Nino in the U.S. are mixed, he said. One benefit has been reduced costs in fuel for heating. A potential worry would be the effects of prolonged temperatures in the 40s and 50s which could lead to a partial bud break of dormant overwintering crops. Many new high temperature records were set in the Great Lakes region in the first part of January, said Andresen.
A week or more of those types of temperatures is normally what is needed to cause trees to come out of dormancy. Once that happens, the cold weather resistance level drops, which results in a greater risk of damage from subsequent cold temperatures.

"If the forecasts do pan out for the latter half of the winter and early spring, which is for mild and dry for the Great Lakes region, this may lead to an earlier than normal start of the growing season," said Andresen. "For many crops, an early start and early planting usually translates into an above average performance of the crop. Overall it's a bit of a mix."

How severe is this El Nino compared to others, especially the infamous 1982-1983 event. Climatologists classify these events by measuring abnormalities in surface pressure and warmth. In terms of warm water in the eastern Pacific and its degree of abnormality, this El Nino is the strongest one of this century.

Despite the serious property damage associated with the Northeast ice storm, New York orchards held up well, according to Kevin Iungerman of Cornell Cooperative Extension's Northern New York Area Fruit Program. Trees are designed to retain strong limbs which can carry the weight of the apple crop. These same trees, if properly managed, can also carry the weight of the ice.

Few if any CA storages in the area have auxiliary power sufficient to maintain full operating capability, said Iungerman. Almost all CA facilities on the northern end of the Champlain Valley were without power for 48 hours, beginning Jan. 8 and 9. A major shipment of emergency helped some packinghouses resume operations by Jan. 10 while all of them were expected to be back up and running by Jan. 14. Iungerman said many of them will be working longer shifts into the weekend to fill orders.