California Drought

Last Chance for El Nino Drought Relief? New Kelvin Waves Cross Pacific

Image: Kelvin waves of high sea level (red/yellow) cross the Pacific Ocean at the equator
Kelvin waves of high sea level (red/yellow) are shown crossing the Pacific Ocean at the equator. The waves can be related to El Niño events. Green indicates normal sea level, and blue/purple areas are lower than normal. Data are from the NASA/European Jason-2 satellite, collected Sept. 13-22, 2014. NASA/JPL-Caltech

Look out, Ecuador: Two Kelvin waves are comin’ at ya. And those waves raise at least the hope of drought relief in parched California, NASA’s Jet Propulsion Laboratory says. Kelvin waves are areas of higher sea level indicating warmer than normal water. In an El Nino, the Pacific Ocean off South America warms, and resulting weather patterns can bring more rain to the western U.S. and elsewhere.

A series of Kelvin waves earlier in the year brought hope that an El Nino would take hold and ease the drought affecting California and the American Southwest. JPL said those waves tapered off, but two new waves were spotted in mid-September moving east across the central and eastern equatorial Pacific.

Those waves, seen in an image from the NASA/European Ocean Surface Topography Mission (OSTM)/Jason-2 satellite, are expected to arrive off Ecuador in late September and early October. But JPL climatologist Bill Patzert said that even if an El Nino does develop, it’s likely to be of only weak or moderate intensity. That might not produce enough rain to really help California, nearly all of which has been suffering through drought for several years.

Hurricane Predictions: El Niño Could Impact Storm Season 1:38



— Gil Aegerter