El Niño Update [21 April 2010]

ENSO Cycle: Recent Evolution, Current Status and Predictions

El Niño Weekly UPDATE prepared by Climate Prediction Center / NCEP –  19 April 2010

The latest weekly SST departures are:

• Niño 4   ~  0.8ºC
• Niño 3.4  ~  0.8ºC
• Niño 3 ~ 0.8ºC
• Niño 1+2 ~ 1.1ºC

El Niño Map. [SOURCE: NOAA/ Climate Prediction Center / NCEP]

Summary

• El Niño is present across the equatorial Pacific Ocean.
• Sea surface temperatures (SST) are more than 1.0ºC above-average across muchof the central and eastern equatorial Pacific.
• Based on current observations and dynamical model forecasts, El Niño is expected to continue through the Northern Hemisphere spring 2010 and transition to ENSO-neutral conditions by Northern Hemisphere summer 2010.

Related Links:

• Your Worst Fears About El Niño

• Climate Locked into ‘Unending’ El Niño?
• What Florida Might Look Like in 2014
• SE Australia Toasted Brown
• UK Flooding
• Speaking of El Niño, OLR Anomalies in Australia
• El Niño Update [16 Nov 2009]
• Recognizing El Niño
• El Niño and La Niña: Tracing the Dance of Ocean and Atmosphere
• TAO Diagrams
• El Niño Forecasts

El Niño Updates – Previous 5 Issues:

• El Niño Update [5 April 2010]
• El Niño Update [29 March 2010]
• El Niño Update [22 March 2010]
• El Niño Update [15 March 2010]
• El Niño Update [8 March 2010]

• El Niño [Main Page, Links to Weekly Updates Archive]

–

Serial No 1,601. Starting April 2010, each entry on this blog has a unique serial number. If any of the numbers are missing, it may mean that the corresponding entry has been blocked by Google/the authorities in your country. Please drop us a line if you detect any anomaly/missing number(s).

Unraveling El Niño Mysteries

The following entry is adopted from a NOAA site. They say their researchers have found clues in stratosphere, troposphere and Arctic Vortex that help them unravel El Niño’s ‘mysteries.’

Unraveling El Niño’s Mysteries: New Clues Found in Stratosphere, Troposphere and Arctic Vortex

El Niño’s emergence in the Pacific Ocean creates ripple effects that extend around the globe.

El Niño (Spanish for “the little boy”) is a natural phenomenon that refers to irregular periods of sea surface temperature warming in the tropical Pacific that impacts global weather patterns.

Supercell. Source NOAA. Click image to enlarge.

El Niño influences our weather:  Ocean temperature, air temperature, ocean currents, winds at various altitudes, air pressure … , and its effects are even more complicated  by human-caused climate change.

El Niño causes weather chaos across the globe:

• More intense storms in the West Coast of  United States,  but  fewer hurricanes in the Atlantic and Gulf Coast.
• India, southeastern Africa, northern Brazil, and Australia usually experience dramatically drier conditions. Shifts in patterns are even stronger in other parts of the world.

Layers of the atmosphere. Source: NOAA. Click image to enlarge.

El Niño creates  highly complex “ripples” that alter atmospheric features from the ocean surface right up to the stratosphere, high above the Earth.

The stratosphere,  a layer of the atmosphere beginning about five miles above sea level, influences weather at ground level. The stratospheric layer of the atmosphere is located above the troposphere.

The troposphere begins at the Earth’s surface and extends up to 6-20 km (4-12 miles) high. We occupy this layer.  The stratosphere begins above the troposphere and extends up to 50 km above the Earth’s surface. This layer holds 19 percent of the atmosphere’s gases but very little water vapor.

Researchers say they have recently found a connection between another atmospheric feature, swirling upper-level winds called the Arctic vortex, and colder than average winters in Europe. They have found links between three factors that also influence the Arctic vortex:

• El Niño
• Cooling of the tropical stratosphere
• Warming of the Arctic stratosphere

More information on El Niño :

• El Niño Update [15 March 2010]
• El Niño [Main Page, Links to Weekly Updates Archive]

El Niño Update [5 Oct 2009]

ENSO Cycle: Recent Evolution, Current Status and Predictions

The following UPDATE is prepared by

Climate Prediction Center / NCEP –  5 Oct 2009

The latest weekly SST departures are:

• Niño 4   ~ 0.8ºC
• Niño 3.4  ~ 0.7ºC
• Niño 3 ~ 0.6ºC
• Niño 1+2 ~ -0.3ºC

El Niño Map. [SOURCE: NOAA/ Climate Prediction Center / NCEP]

Highlights

SST Departures (ºC) in the Tropical Pacific During the Last 4 Weeks
During the last 4-weeks, equatorial SSTs were at least1.0°C above average across parts of the central and eastern Pacific.

Global SST Departures (ºC)
During the last four weeks, equatorial SSTs were above-average in the Pacific and Indian Oceans. Also, above-average SSTs covered large areas of the Northern Hemisphere subtropics and mid-latitudes.

Weekly SST Departures (ºC) for the Last Four Weeks

• During the last four weeks, SST anomalies remained positive across the equatorial Pacific Ocean.
• During the last month, SST anomalies decreased over the eastern equatorial SST.

Sub-Surface Temperature Departures (ºC) in the Equatorial Pacific

Atmospheric Circulation over the North Pacific & North America During the Last 60 Days
During early August through September, an anomalous trough was prevalent in the North Pacific Ocean/Gulf of Alaska. During September, an anomalous ridge was present downstream, focused over Canada and the northern United States. The pattern also featured a weak trough over thecentral U.S., which contributed to cooling in the region, while the northern U.S. and Canada remained warmer-than-average.

The most recent ONI value (July –September 2009) is +0.8oC.

Summary

• El Niño is present across the equatorial Pacific Ocean.
• Sea surface temperatures (SST) were at least 1.0ºC above-average across much of the central and east-central equatorial Pacific.
• Based on current observations and dynamical model forecasts, El Niño is expected to strengthen and last through Northern Hemisphere winter 2009-10.

Related Links:

• Recognizing El Niño
• El Niño and La Niña: Tracing the Dance of Ocean and Atmosphere
• TAO Diagrams
• El Niño Forecasts

El Niño Updates:

• El Niño [Main Page]

• 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 [17 Aug 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
• El Niño Update # 1
• El Niño conditions is in progress —NOAA
• El Niño event almost certain: BOM
• El Niño could develop June – August 2009
• World Now
• 2009 Hurricane Season