The bad boy of seasonal weather known as El Nino seems to be changing its ways -- growing stronger over the last few decades and shifting its pattern of extra-warm sea surface temperatures from the shores of South America to the tropical Central Pacific Ocean.
Studying measurements from space-borne instruments, scientists say the El Nino that came to an end in May was one of this new type of Central Pacific El Nino and was the strongest yet. The images, above, developed from NOAA's polar-orbiting satellites and NASA's Jason-1 spacecraft, show unusually high ocean temperatures and sea level center in the Central Pacific rather than the Eastern Pacific, as the 2009-'10 El Nino reached its peak. More typically, wedge-shaped patterns of these features would be seen farther east, up against the coast of South America.
Researchers continue to puzzle over the link between our changing climate and this natural age-old phenomenon that periodically shifts seasonal weather patterns around the world. El Nino is not to blame for global warming, they conclude, but how will rising global temperatures impact El Nino?
Reporting recently in the journal Geophysical Research Letters, Tong Lee of NASA's Jet Propulsion Laboratory in Pasadena writes that he and Michael McPhaden at NOAA's Pacific Marine Environmental Laboratory in Seattle now are able to answer one question about changing conditions in the tropical Pacific.
"Our study concludes the long-term warming trend seen in the central Pacific is primarily due to more intense El Ninos, rather than a general rise of background temperatures," Lee said in a statement released by NASA.
McPhaden said results of the study "suggest climate change may already be affecting El Nino by shifting the center of action from the eastern to the central Pacific."
Long-range weather forecasters, making seasonal predictions months in advance, have been relying on shifting surface temperatures in the equatorial Pacific to help foresee patterns of precipitation and temperature, especially during North America's winter, and the frequency of Atlantic Basin hurricanes which are affected by El Nino comings and goings. With the new type of El Nino, however, forecasters probably are going to have to change their thinking.
"El Nino's impact on global weather patterns is different if ocean warming occurs primarily in the central Pacific, instead of the eastern Pacific," said McPhaden. "If the trend we observe continues, it could throw a monkey wrench into long-range weather forecasting, which is largely based on our understanding of El Ninos from the latter half of the 20th century."
Studying measurements from space-borne instruments, scientists say the El Nino that came to an end in May was one of this new type of Central Pacific El Nino and was the strongest yet. The images, above, developed from NOAA's polar-orbiting satellites and NASA's Jason-1 spacecraft, show unusually high ocean temperatures and sea level center in the Central Pacific rather than the Eastern Pacific, as the 2009-'10 El Nino reached its peak. More typically, wedge-shaped patterns of these features would be seen farther east, up against the coast of South America.
Researchers continue to puzzle over the link between our changing climate and this natural age-old phenomenon that periodically shifts seasonal weather patterns around the world. El Nino is not to blame for global warming, they conclude, but how will rising global temperatures impact El Nino?
Reporting recently in the journal Geophysical Research Letters, Tong Lee of NASA's Jet Propulsion Laboratory in Pasadena writes that he and Michael McPhaden at NOAA's Pacific Marine Environmental Laboratory in Seattle now are able to answer one question about changing conditions in the tropical Pacific.
"Our study concludes the long-term warming trend seen in the central Pacific is primarily due to more intense El Ninos, rather than a general rise of background temperatures," Lee said in a statement released by NASA.
McPhaden said results of the study "suggest climate change may already be affecting El Nino by shifting the center of action from the eastern to the central Pacific."
Long-range weather forecasters, making seasonal predictions months in advance, have been relying on shifting surface temperatures in the equatorial Pacific to help foresee patterns of precipitation and temperature, especially during North America's winter, and the frequency of Atlantic Basin hurricanes which are affected by El Nino comings and goings. With the new type of El Nino, however, forecasters probably are going to have to change their thinking.
"El Nino's impact on global weather patterns is different if ocean warming occurs primarily in the central Pacific, instead of the eastern Pacific," said McPhaden. "If the trend we observe continues, it could throw a monkey wrench into long-range weather forecasting, which is largely based on our understanding of El Ninos from the latter half of the 20th century."
Tags: Climate Change, Global Warming, Hurricanes, Meteorology, Weather
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