Wet (But Warm) Winter: Strong El Niño to Usher in Lots of Rain
Jeanna Bryner, LiveScience.com Yahoo News 15 Oct 15;
Sea-surface height is an indicator of water temperature because warm water expands.
El Niño is expected to be more beast than "little boy" this year — a forecast about the weather pattern that becomes clear in newly released maps of the waters around the equatorial Pacific Ocean.
The two maps show the sea-surface heights in the Pacific in October 1997 and 2015, revealing that conditions this year are looking a lot like they did during the strong El Niño event of 1997 to 1998. Water expands as temperatures rise, and so sea-surface height is an indicator of warming in the upper layer of the ocean.
"Whether El Niño gets slightly stronger or a little weaker is not statistically significant now. This baby is too big to fail," Bill Patzert, a climatologist at NASA's Jet Propulsion Laboratory in Pasadena, California, told NASA's Earth Observatory.
During an El Niño — which translates as "The Little Boy" in Spanish — an ocean-atmosphere interaction leads to the warming of surface waters in the central and east-central Pacific around the equator. The cyclical phenomenon can affect wind and rainfall patterns worldwide. [How El Niño Causes Wild Weather All Over the Globe (Infographic)]
"Over North America, this winter will definitely not be normal. However, the climatic events of the past decade make 'normal' difficult to define," Patzert told the Earth Observatory.
Measurements of sea-surface heights in the newly released maps came from altimeters onboard the TOPEX/Poseidon satellite (1997) and the Jason-2 satellite (2015). The warmest waters, which are represented by sea-surface heights above normal sea level, can be seen (in red) moving into the eastern tropical Pacific Ocean, while the colder-than-normal — or below-normal sea-surface heights — show up in blue in the western tropical Pacific Ocean.
Experts with the Climate Prediction Center, part of the National Oceanic and Atmospheric Administration, forecast last month that this year's El Niño could be among the strongest on record, dating back to 1950. In August, sea-surface temperatures in the eastern equatorial Pacific Ocean were near or greater than 3.6 degrees Fahrenheit (2 degrees Celsius) above the 1981 to 2010 average, according to the Climate Prediction Center.
The climate pattern is linked with snowy winters in the Northwestern United States and wet winters in the Southwest; drought in Southeast Asia and Australia typically accompany El Niño.
U.S. winter weather to see El Nino's influence: report
Letitia Stein PlanetArk 16 Oct 15;
Much of the U.S. South can expect a cooler and wetter winter, while warmer than usual temperatures are likely across many northern and western states, as a strong El Niño weather pattern shaped a government weather outlook issued on Thursday.
More rain and snow are likely across the nation's southern regions, extending from central California to Texas and Florida and up the East Coast to southern New England, according to the National Oceanic and Atmospheric Administration (NOAA).
Its outlook did not forecast the intensity or frequency of storms.
While potentially good news for drought-stricken California, a single winter is unlikely to erase the state's four dry years, the outlook noted.
"California would need close to twice its normal rainfall to get out of drought and that's unlikely," said Mike Halpert, deputy director of NOAA's Climate Prediction Center, in a statement.
The 2015-2016 winter may be colder than usual from Georgia through New Mexico, while northern-tier states and the West Coast will see warmer than normal temperatures, the report noted.
The outlook reflects the influence of one of the strongest El Niño weather patterns on record, forecasters said.
El Niño is a warming of ocean surface temperatures in the eastern and central Pacific that occurs every few years, with global weather implications.
(Editing by Sandra Maler)