Contact:  Stephanie Kenitzer          FOR IMMEDIATE RELEASE
          Climate Prediction Center   June 17, 1997
          Analysis Branch                                
     

Scientists at the center said, however, that forecasts for the summer were more uncertain because El Nino impacts during this time normally are not consistent. The current Climate Prediction Center forecast for the summer is for above normal temperatures in the southeast and southwest with cooler than normal conditions from Oklahoma northwestward to Idaho.

El Nino is an abnormal state of the ocean-atmosphere system in the tropical Pacific with important consequences for weather around the globe.

"These are the typical weather impacts during a warm phase based on an average of all El Nino events," said Ants Leetmaa, director of the Climate Prediction Center. "This El Nino event is shaping up to be similar to the strong events of 1957, 1972 and 1982-83. During those years, many sections of the southern half of the United States, including California, experienced above normal rainfall from September through the following May."

El Nino is an abnormal state of the ocean-atmosphere system in the tropical Pacific having important consequences for weather around the globe. Among these consequences are increased rainfall across the southern tier of the United States and in Peru, sometimes resulting in destructive flooding; and drought in northeast Brazil, southeastern Africa, and the west Pacific.

El Ninos usually occur approximately every two to seven years. Recent El Nino events occurred in 1976-1977, 1982-1983, 1986-1987, 1991-1993 and 1994-1995. The first half of the 1990s is unusual in that four out of five years featured weak warm episode conditions in the tropical Pacific. However, a cold episode occurred in 1995/96 and its effects lingered until late 1996.

Observations of conditions in the tropical Pacific are essential for the prediction of short term climate variations. To provide necessary data, NOAA operates a network of buoys that measure temperature, currents and winds in the equatorial band. These buoys transmit data that are critical to researchers and forecasters around the world in real time. Data from NOAA and NASA satellites also provide valuable insight into changes in sea surface temperatures.

Better predictions of extreme climate episodes like floods and droughts could save the United States billions of dollars in damage costs. Predicting the onset of a warm or cold phase is critical in helping water, energy and transportation managers, and farmers plan for, avoid or mitigate potential losses. For example, NOAA's National Marine Fisheries Service expects the ocean warming of California waters caused by the summer arrival of El Nino to bring bonus fishing for southern California anglers but lean times for other fisheries, including salmon and rockfish, and for certain marine mammals.

NOAA scientists and fisheries managers are still learning about El Nino effects and how to best manage human activities potentially affected by these naturally occurring changes.

"If the El Nino episode strengthens, we should see tropical and temperate marine species shift northward beyond their normal ranges, and other changes in marine life," said Willam Hogarth, acting regional administrator of the fisheries service's Southwest regional office in Long Beach, Calif. "We are particularly concerned about changes in the growth and production of some of our resident species."

Fisheries service scientists expect favorable conditions for mahimahi and billfish, as well as certain small schooling fish such as mackerel and sardines. Officials note the early appearance of migrating yellowtail, albacore and bluefin tuna in Southern California waters may be an effect of El Nino . However, some bottomfish, such as the commercially valuable rockfish, may be vulnerable to warmer water conditions because they are bound to local sea floor topography.

Californians may also see an increase in dead and live strandings of seals and sea lions along the coast. Fisheries service scientists suspect that El Nino conditions trigger a decline in the food supply of some marine predators. However, periodic increases or decreases in the stranding rates of these animals do not reflect a danger to the health of the populations.