Scientist of the National Oceanic and Atmospheric Administration (NOAA) 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. The most recent El Niño occurred in 2006.
NOAA expects this El Niño to continue developing during the next several months, with further strengthening possible. The event is expected to last through winter 2009-10.
Contrary to popular belief, not all effects are negative: El Niño can for example help to suppress Atlantic hurricane activity. In the United States, it typically brings beneficial winter precipitation to the arid Southwest, less wintry weather across the North, and a reduced risk of Florida wildfires.
This phenomenon’s negative impacts have included damaging winter storms in California and increased storminess across the southern United States, as well as produced severe flooding and mudslides in Central and South America, and drought in Indonesia.
An El Niño event may significantly diminish ocean productivity off the west coast by limiting weather patterns that cause upwelling, or nutrient circulation in the ocean. These nutrients are the foundation of a vibrant marine food web and could negatively impact food sources for several types of birds, fish and marine mammals.
In its monthly El Niño diagnostics discussion, scientists with the NOAA National Weather Service Climate Prediction Center noted weekly eastern equatorial Pacific sea surface temperatures were at least 1.0 degree C (1.8 degree F) above average at the end of June.
NOAA will continue to monitor the rapidly evolving situation in the tropical Pacific, and will provide more detailed information on possible Atlantic hurricane impacts in its updated Seasonal Hurricane Outlook scheduled for release on August 6, 2009.
Copyright © 2009 by Marine Science Today, a publication of OceanLines LLC