UPDATE:
NOAA scientists today [July 9, 2009] announced the arrival of El Niño, a climate phenomenon with a significant influence on global weather, ocean conditions and marine fisheries. El Niño, the periodic warming of central and eastern tropical Pacific waters, occurs on average every two to five years and typically lasts about 12 months. See NOAA Press Release
The El Niño weather pattern can cause global weather chaos by exacerbating droughts and floods.
Conditions are favorable for a transition from ENSO-neutral to El Niño conditions during June – August 2009, US Climate Prediction Center says.
During El Nino, rainfall and thunderstorm activity diminishes over the western equatorial Pacific, and increases over the eastern half of the tropical Pacific. This area of increased rainfall occurs where the exceptionally warm ocean waters have reached about 28°C or 82°F. This overall pattern of rainfall departures spans nearly one-half the distance around the globe, and is responsible for many of the global weather impacts caused by El Niño.
El Niño occurs when the eastern Pacific temperatures rise above average, and the forecast says conditions are now favorable for a switch from ENSO-neutarl to El Niño conditions between June and August 2009. The forecast warns that by end May 2009 sea surface temperatures (SST) had increased for the fifth consecutive month, rising to “above-average” in the equatorial Pacific Ocean.
The 1997-98 El Niño/Southern Oscillation was one of the most severe ENSO events in history. It caused widespread drought in Australia and Indonesia and floods in S. America, especially Ecuador and Peru.
FEWW Moderators estimate that a new episode of El Niño, which would have devastating impact globally, could cause up to $500 billion in damages.
Graphical depiction of the four Niño regions. [Source: NOAA/ National Weather Service National Centers for Environmental Prediction Climate Prediction Center]
The report is available at EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION
For regular updates see comments section below.
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