Pacific Ocean sea-surface height measurements and atmospheric water vapor information taken from two independent Earth-orbiting satellites are providing more convincing evidence that the weather-disrupting phenomenon known as El Nino is back and strong . "The new data collected since April 1997 confirm what we had earlier speculated upon and what the National Oceanic and Atmospheric Administration (NOAA) has predicted -- a full-blown El Nino condition is established in the Pacific," said Dr. Lee-Lueng Fu, project scientist for the U.S./French satellite TOPEX/POSEIDON satellite at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA. "The recent data are showing us that a large warm water mass with high sea-surface elevations, about six inches (15 centimeters) above normal, is occupying the entire tropical Pacific Ocean east of the international date line. In fact, the surface area covered by the warm water mass is about one-and-a-half times the size of the continental United States," Fu said. "We watched this warm water mass travel eastward from the western Pacific along the equator earlier this spring. Right now, sea-surface height off the South American coast is 10 inches (25 centimeters) higher than normal, which is comparable with the conditions during the so-called 'El Nino of the century' in 1982-83." In addition, recent atmospheric water vapor data collected from NASA's Upper Atmosphere Research Satellite (UARS) show tell-tale signs of an El Nino condition in the tropical Pacific Ocean. "The Microwave Limb Sounder experiment on UARS is detecting an unusually large build-up of water vapor in the atmosphere at heights of approximately eight miles (12 kilometers) over the central-eastern tropical Pacific. Not since the last strong El Nino winter of 1991-92 have we seen such a large build-up of water vapor in this part of the atmosphere," said JPL's Dr. William Read. "Increased water vapor at these heights can be associated with more intense wintertime storm activity from the 'pineapple express', a pattern of atmospheric motions that brings tropical moisture from Hawaii to the southwestern United States."--NASA press release.