November 30, 2006
Monga Bay
El Niño's to blame for the quiet 2006 hurricane season according to researchers at the U.S. National Oceanic and Atmospheric Administration (NOAA).
Image: NASA / Akiko Hayashi, Jet Propulsion Laboratory.
While some climate scientists forecast a big hurricane year in 2006, the official six-month season produced only nine tropical storms and hurricanes, below the average of 11. For the first time since 1997, there were no Category 4 or 5 hurricanes, the strongest type of storm. 2005 saw the worst hurricane season on record with 28 storms including 3 category 5 storms: Hurricanes Katrina, Rita, and Wilma. Hurricane Katrina caused some $80 billion in damage as it destroyed the city of New Orleans.
Researchers say that El Niño, a periodic warming of the eastern Pacific ocean, tends to surpress hurricane activity in the Atlantic by increasing wind shear that disrupts storm formation. ElNiño is also correlated with above average precipitation in the wastern United States and coastal South America, and droughts in Indonesia and northern Australia.
“The development of El Niño conditions by September helps explain why this Atlantic hurricane season was less active than predicted,” said Gerry Bell, NOAA’s lead forecaster on the Atlantic hurricane seasonal outlook team. “El Niño developed quickly and the atmosphere responded rapidly, reducing hurricane activity during an otherwise active era that began in 1995.”
According to NASA, late 2006 has been characterized by weak El Niño conditions in the the tropical Pacific Ocean, but scientists are unsure how long the conditions will persist, meaning strong hurricanes could return as soon as next year.
