Sea Surface Temperature Images
50 KM Global Analysis – updated weekly.
Above is a freeze frame of the top image used for comparison.
Current SST Anomalies
Above is a freeze frame of the top image used for comparison.
NOAA Operational Definitions for El Niño and La Niña
El Niño: characterized by a positive ONI greater than or equal to +0.5°C.
La Niña: characterized by a negative ONI less than or equal to -0.5°C.
By historical standards, to be classified as a full-fledged El Niño or La Niña episode, these thresholds must be exceeded for a period of at least 5 consecutive overlapping 3-month seasons.
CPC considers El Niño or La Niña conditions to occur when the monthly Niño3.4 SST departures meet or exceed +/-0.5°C along with consistent atmospheric features. These anomalies must also be forecasted to persist for 3 consecutive months.
Above is a freeze frame of the top animation used for comparison.
ENSO ALERT SYSTEM [Click Here]
The Climate Prediction Center defines. . .
“El Niño conditions” as existing when:
- A one-month positive sea surface temperature anomaly of 0.5C or greater is observed in the Niño-3.4 region of the equatorial Pacific Ocean (5ºN-5ºS, 120ºW-170ºW) and an expectation that the 3-month Oceanic Niño Index (ONI) threshold will be met AND
- An atmospheric response typically associated with El Niño is observed over the equatorial Pacific Ocean (see The ENSO Cycle).
“La Niña conditions” as existing when:
- A one-month negative sea surface temperature anomaly of -0.5C or less is observed in the Niño-3.4 region of the equatorial Pacific Ocean (5ºN-5ºS, 120ºW-170ºW) and an expectation that the 3-month Oceanic Niño Index (ONI) threshold will be met AND
- An atmospheric response typically associated with La Niña is observed over the equatorial Pacific Ocean (see The ENSO Cycle).
El Niño status [NOAA/ NWS/ CPC]
Weekly ENSO Update (Updated Mondays) pdf File
CFS Forecast of Seasonal Climate Anomalies for Apr 2009 to Dec 2009
Overview: El Niño and La Niña
El Niño (Southern Oscillation, ENSO, or El Niño) and La Niña phenomenon are sustained sea surface temperature anomalies of greater than 0.5°C, which occur naturally in 2-7 year cycles of the ocean-atmosphere system in the central tropical Eastern Pacific Ocean with important consequences for global weather. El Niño is associated with warmer than usual ocean temperatures; La Niña is associated with unusually cold ocean temperatures.
When the anomaly lasts for a less than five months, it is categorized as El Niño or La Niña condition; if the condition persists for longer than 5 months, it is categorized as El Niño or La Niña episode. Previously, the episodes have occurred at irregular 2- to 7-year intervals, usually persisting for one or two years.
- Major ENSO events have occurred in the years 1790-93, 1828, 1876-78, 1891, 1925-26, 1982-83, and 1997-98*
- Recent El Niños have occurred in 1986-1987, 1991-1992, 1993, 1994, 1997-1998, 2002-2003, 2004-2005 and 2006-2007
- The 1997-98 had one of the worst impact globbaly, which claimed thousands of live and caused an estimated $90-100 billion worth of damage globally.
NOAA Press Release:
El Niño Arrives; Expected to Persist through Winter 2009-10
July 9, 2009
NOAA scientists today 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.
Sea surface temperatures along the equatorial Eastern Pacific, as of July 1, are at least one degree above average — a sign of El Niño. Animation.
High resolution (Credit: NOAA)
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.
“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 depend on a variety of factors, such as intensity and extent of ocean warming, and the time of year. Contrary to popular belief, not all effects are negative. On the positive side, El Niño can 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.
El Niño’s negative impacts have included damaging winter storms in California and increased storminess across the southern United States. Some past El Niños have also 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 today, 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. The most recent El Niño occurred in 2006.
El Niño includes weaker trade winds, increased rainfall over the central tropical Pacific, and decreased rainfall in Indonesia. These vast rainfall patterns in the tropics are responsible for many of El Niño’s global effects on weather patterns.
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.
NOAA understands and predicts changes in the Earth’s environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.
- Recognizing El Niño
- El Niño and La Niña: Tracing the Dance of Ocean and Atmosphere
- TAO Diagrams
- El Niño Forecasts
- Impact of El Niño and La Niña on Rainfall
El Niño Updates
- El Niño Weekly Update [21 Dec 2009]
- Climate Locked into ‘Unending’ El Niño? [UPDATE 14 Dec 2009]
- El Niño Weekly Update [7 Dec 2009]
- El Niño Update [30 Nov 2009]
- El Niño Update [23 Nov 2009]
- El Niño Update [16 Nov 2009]
- El Niño Update [10 Nov 2009]
- El Niño Update [2 Nov 2009]
- El Niño Update [28 Oct 2009]
- El Niño Update [20 Oct 2009]
- El Niño Update [13 Oct 2009]
- El Niño Update [5 Oct 2009]
- El Niño Update [28 Sept 2009]
- El Niño Update [21 Sept 2009]
- El Niño Update [14 Sept 2009]
- El Niño Update [8 Sept 2009]
- El Niño Update [31 Aug 2009]
- El Niño Update [24 Aug 2009]
- El Niño Update – 17 August 2009
- El Niño Update – 10 August 2009
- El Niño Update – 3 August 2009
- El Niño Update – 27 July 2009
- El Niño Update – 20 July 2009
Other Related Links: