NOAA scientists 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.
It is anticipated that this time around
El Niño will continue to develop over the next few months and it is possible it will grow stronger. Look for this to last until winter 2009-10.
“Advanced climate science allows us to alert industries, governments and emergency managers about the weather conditions El Niño may bring so these can be factored into decision-making and ultimately protect life, property and the economy,” said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator.
El Niño's
impacts are both positive and negative. For example, El Niño can help to suppress Atlantic hurricane activity; this is a positive effect.
El Niño
typically brings beneficial winter precipitation to the arid Southwest United States as well as less wintry weather across the North, and a reduced risk of Florida wildfires.
On the negative side, damaging winter storms in California and increased storminess across the southern United States. Severe flooding and mudslides in Central and South America, and drought in Indonesia have also happened.
An El Niño event may limit weather patterns that cause upwelling, or nutrient circulation in the ocean. This impacts the ocean food supply and productivity as 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.
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 above average at the end of June.
Weaker trade winds, increased rainfall over the central tropical Pacific, and decreased rainfall in Indonesia are all due to El Niño. These vast rainfall patterns in the tropics are responsible for many of El Niño’s global effects on weather patterns.
