The Solar Cycle and Weather Patterns

A group of international scientists and those from the National Center for Atmospheric Research (NCAR) have recently found an answer to a difficult question that involves the solar cycle and its potential impacts on the earth's weather patterns, according to EurekAlert.

Here is the question......If the total energy that reaches Earth from the Sun varies by only 0.1 percent across the approximately 11-year solar cycle, how can such a small variation drive major changes in weather patterns on Earth?

Here is what they found.....Chemicals in the stratosphere and sea surface temperatures in the Pacific Ocean respond during solar maximum in a way that amplifies the Sun's influence on some aspects of air movement. This can intensify winds and rainfall, change sea surface temperatures and cloud cover over certain tropical and subtropical regions, and ultimately influence global weather.

An example of an active sun, loaded with spots.

The most recent look at the sun. No spots!

Excerpts from the article........

One example was that the sun, the stratosphere and the oceans are connected in ways that can influence events such as winter rainfall in North America," says NCAR scientist Gerald Meehl, the lead author.

The slight increase in solar energy during the peak production of sunspots is absorbed by stratospheric ozone. The energy warms the air in the stratosphere over the tropics, where sunlight is most intense, while also stimulating the production of additional ozone there that absorbs even more solar energy. Since the stratosphere warms unevenly, with the most pronounced warming occurring at lower latitudes, stratospheric winds are altered and, through a chain of interconnected processes, end up strengthening tropical precipitation.

Earth's response to the solar cycle continues for a year or two following peak sunspot activity. The La Nina-like pattern triggered by the solar maximum tends to evolve into a pattern similar to El Nino as slow-moving currents replace the cool water over the eastern tropical Pacific with warmer water. The ocean response is only about half as strong as with El Nino and the lagged warmth is not as consistent as the La Nina-like pattern that occurs during peaks in the solar cycle.

The solar maximum could potentially enhance a true La Nina event or dampen a true El Nino event. The La Nina of 1988-89 occurred near the peak of solar maximum. That La Nina became unusually strong and was associated with significant changes in weather patterns, such as an unusually mild and dry winter in the southwestern United States.

La Niña fading, El Niño may soon return

Sea Surface Temperatures as of 5-11-09 click for larger image

Source: http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.5.11.2009.gif

Bill Illis writes in comments:

The newest Ocean SST map shows the La Nina conditions have gone away and we are in slightly positive ENSO conditions.

Also interesting is that the negative PDO seems to be moving back to neutral right now. The cool SST conditions off of Alaska (which has been there for 3 years now) looks to be moderating as well.

From my perspective, the other interesting feature is how the recent La Ninas have loaded up cool SSTs in the Pacific off south-east Asia which will soon move into the Kuroshio currrent which will then flow across the north Pacific.

The upper ocean heat content is signaling we are going to move rapidly into El Nino conditions although most forecasts are calling for neutral conditions.

Source:

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/anim/wkxzteq_anm.gif

Atmospheric Angular Momentum has really turned negative recently (signaling La Nina), the Trade Winds have fallen off to nothing (signaling El Nino).

So overall, the north Pacific is offically schizophrenic right now.

NOAA Unveils New Alert System for La Niña and El Niño

Can’t you just see this scrolling across your TV during an EAS alert?”…. If this had been an actual El Niño, you would have been instructed on where to complain to your nearest modeler turned forecaster….” I wonder what kind of graphical icon TWC will come up with for an El Niño Watch? - Anthony

FOR IMMEDIATE RELEASE

Feb. 5, 2009

Contact: Linda Joy
301 713-0622, ext. 127

NOAA Unveils New Alert System for La Niña and El Niño

La Niña Likely to Continue into Spring

NOAA’s Climate Prediction Center today issued the first La Niña advisory under its new El Niño Southern Oscillation (ENSO) Alert System. Forecasters expect La Niña to influence weather patterns across the United States during the remainder of the winter and into the early spring.

Defined as cooler than normal sea surface temperatures in the central and eastern equatorial Pacific Ocean, La Niña impacts the weather globally. La Niña’s opposite is El Niño, or warmer than normal ocean temperatures. These changes in ocean temperatures alter the tropical wind and rainfall patterns with far reaching implications.

“The typical weather patterns associated with La Niña and El Niño affect many industries including agriculture, transportation, energy, shipping and construction,” said Michael S. Halpert, deputy director of the Climate Prediction Center. “The ENSO Alert System will succinctly inform industry, government agencies, academia and the public about the onset and status of La Niña and El Niño. This system will also help decision makers plan for the potential effects presented by these conditions.”

La Niña conditions have been present since late December, but it is too early to say exactly how strong the event will be and precisely how long it will last. However, for the next few months La Niña is expected to bring milder and drier than average conditions to the southeastern and southwestern states. It is also expected to bring wetter-than-average conditions to the Ohio and Tennessee valleys, and cooler than average temperatures to the Pacific Northwest.

The new ENSO alert system includes La Niña and El Niño watches and advisories which the Climate Prediction Center will issue when specific conditions exist.

• La Niña or El Niño Watch: conditions in the equatorial Pacific are favorable for the development of La Niña or El Niño conditions in the next three months.
• La Niña or El Niño Advisory: La Niña or El Niño conditions have developed and are expected to continue.

These watches and advisories are now part of the ENSO Diagnostic Discussion, which is issued by the Climate Prediction Center on the Thursday falling between the 5^th and 11^th of every month. It is available online at http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory.

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.

- 30 -

La Niña is back

In a document published January 19th, NOAA’s Climate Prediction Center (NCEP) has officially put the stamp on the cold water conditions we’ve seen growing in the equatorial mid and eastern Pacific. I first reported on this on December 4th, 2008. This does not bode well for California’s drought conditions, which are likely to continue due to this renewed La Niña event.

Sea Surface Temperatures as of January 5th, 2009. Click for a larger image

In the document, which you can see here, NCEP says:

•Atmospheric and oceanic conditions reflect La Niña.
•Negative equatorial SST anomalies persist across the central and eastern Pacific Ocean.
•Based on recent trends in the observations and model forecasts,La Niña conditions are likely to continue into Northern Hemisphere Spring 2009.

Here is a map provided that shows the precipitation departure for the last 90 days. Note that while the Pacific northwest (notably Seattle) is taking a bath, California gets nearly nothing. The jet stream pattern has been pushed far north this past year.

I also found this time series graph of equatorial Pacific ocean heat content anomaly for 180 to 100 degrees west of particular interest:

They also say that:

A majority of ENSO forecasts indicate below-average SSTs in the central equatorial Pacific through Northern Hemisphere Summer 2009, with about half of the models suggesting La Niña conditions will continue through February-March-April 2009.

Place your bets now.

There is also a wealth of information in the PDF document NCEP has prepared. I’m sure our readers can draw some interesting conclusions and analyses from it.

A hat tip to WUWT reader Alan Wilkinson for bringing the NCEP document to my attention.