Scientific American (August 2000) by Scientific American

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The ocean off Peru becomes unusually warm and stays that way for months before returning to normal or going to a cold extreme (La Niña). The name “Southern Oscillation” Disease Outbreaks refers to atmospheric changes that happen in tandem with the Accompanying Extreme Weather during the Pacific’s shifts to warmer or cool1997– 98 El Niño er conditions. During an El Niño,evaporation from the heated eastern Pacific Extreme Weather can lead to abnormally heavy rains in parts of South America and Africa; meanwhile other areas of South America and Africa 1993, were long-lasting drought interrupted by intense rains.

Subsequent work by Mundt, Bo Reipurth of the European Southern Observatory in Santiago, Chile, and others (including me) showed that jets from young stars stretch for several lightyears. They are closely related to HerbigHaro objects. In fact, some such objects turned out to be nothing more than the brightest parts of jets. Others were discovered to be bow shocks caused by jets as they plow their way supersonically through ambient gas, like the shock wave that surrounds a bullet zinging through the air.

True to the models, malaria is reappearing north and south of the tropics. S. has long been home to Anopheles mosquitoes, and malaria circulated here decades ago. By the 1980s mosquito-control programs and other public health measures had restricted the disorder to California. Since 1990, however, when the hottest decade on record began, outbreaks of locally transmitted malaria have occurred during hot spells in Texas, Florida, Georgia, Michigan, New Jersey and New York (as well as in Toronto).