Monday, April 27, 2015

Wind Bursts Strongly Affect El Nino Severity

http://www.sciencedaily.com/releases/2015/04/150415155358.htm

A new study published online April 13, 2015, in the journal Nature Geoscience finds that prolonged wind bursts originating in the western Pacific can have a strong effect on whether an El Niño event will occur and how severe it is likely to be. In addition, the paper identifies three distinct varieties or "flavors" of El Niño, and explains how these westerly wind bursts (WWBs) can determine which of these flavors will take shape. The findings should help refine future predictions of these global-scale climate events.
"These westerly wind bursts are intraseasonal--they're not weather, they're not climate, but somewhere in between," said Raghu Murtugudde, a professor of atmospheric and oceanic science at the University of Maryland who is a coauthor on the study. "Our study shows that the wind bursts are definitely having an effect. We better learn to predict them if we are going to have skillful El Niño predictions."
The researchers analyzed 50 years of tropical Pacific sea surface temperature and westerly wind burst data. They found differences, especially when comparing the data from this year's weak El Niño event with the record-breaking event of 1997/98.
"The most notable difference was the existence of strong westerly winds extending from the western to central equatorial Pacific in May 1997, which were not seen in 2014," said Murtugudde, who also has an appointment in the university's Earth System Science Interdisciplinary Center (ESSIC). "The development of strong westerly winds in the central equatorial Pacific in association with the warming to its east appears to be an essential element of large El Niño events."

No comments:

Post a Comment