Scientists say Earth has warmed to record temperatures in 1988 and drought will be more likely, especially in the Southeast and Midwest, unless industrial and auto emissions believed responsible are cut sharply.

In a grim presentation to the Senate Energy and Natural Resources Committee Thursday, atmospheric experts said they have a "high degree of confidence" that the pollution-related "greenhouse effect" is responsible for a rapid rise in global temperatures during the past 20 years.On a day when the outside temperature neared 100 degrees Fahrenheit, they warned the planet faces climatic catastrophe unless industrialized nations cut by 40 to 50 percent the use of fossil fuels such as oil, coal and natural gas.

The burning of fossil fuels by cars and factories releases carbon dioxide and other gases that build up in the atmosphere, trapping rising heat that usually would escape into space - the same principle found in greenhouses.

"It is hot out today, and unless we change our ways of producing energy, it's going to get hotter," declared Michael Oppenheimer, an atmospheric physicist with the Environmental Defense Fund.

Oppenheimer said no researcher could say the drought now plaguing much of the nation's midsection is the result of the greenhouse effect. However, he said, "The Midwest drought is a warning. It provides a small taste of the dislocations society will face with increasing frequency if we fail to act."