UK Ireland winter
© Image MODIS
View of Ireland and UK from space on Christmas Day 2010.
The trend of severe winter weather could be set to continue according to new research.

A number of senior UK-based academics have published their findings in the journal Environmental Research Letters. The basis for the wintry outlook is that relatively cold winters in the United Kingdom and Ireland are more common when solar activity is low.

The findings follow on from one of the coldest winters experienced in Ireland and Britain in more than 45 years.

Using the Central England Temperature (CET) record, which dates back to mid-17th century, the research team said that average temperatures during recent winters had been markedly lower than the longer-term average.

According to the authors of the new report: "The mean CET for December, January and February for the recent relatively cold winters of 2008/09 and 2009/10 were 3.50C and 2.53C respectively. Whereas the mean value for the previous 20 winters had been 5.04C. The cluster of lower winter temperatures in the UK during the last three years had raised questions about the probability of more similar, or even colder, winters occurring in the future".

winter
© Liam O'Dowd
Mid Winters Night 2010, Stacks Mountain, Kerry.
"Little Ice-Age"

The report authors noted, however, that their findings do not indicate that The British Isles are set to experience a 'Little Ice Age', similar to what occurred from 16th to the 19th centuries.

Several causes of the Little Ice Age have been proposed in the past. They include cyclical lows in solar radiation, heightened volcanic activity, changes in the ocean circulation, or an inherent variability in global climate.

Co-author Mike Lockwood, professor of space environment physics at the University of Reading stressed that the "Little Ice Age" was not an ice age in the strictest sense of the word. He explained that data from the CET showed "the coldest winter since records began was 1683/84 yet just two year later, right in the middle of the Maunder Minimum, is the fifth warmest winter in the whole record, so this idea that Maunder Minimum winters were unrelentingly cold is wrong".

Commenting on solar activity and its potential impact on the climate, Professor Lockwood explained: "Solar activity during the current sunspot minimum has fallen to levels unknown since the start of the 20th century. The Maunder minimum (about 1650 - 1700) was a prolonged episode of low solar activity which coincided with more severe winters in the United Kingdom and continental Europe. Motivated by recent relatively cold winters in the UK, we investigate the possible connection with solar activity.

"We identify regionally anomalous cold winters by detrending the Central England temperature (CET) record using reconstructions of the northern hemisphere mean temperature. We show that cold winter excursions from the hemispheric trend occur more commonly in the UK during low solar activity, consistent with the solar influence on the occurrence of persistent blocking events in the eastern Atlantic.

"We stress that this is a regional and seasonal effect relating to European winters and not a global effect. Average solar activity has declined rapidly since 1985 and cosmogenic isotopes suggest an 8% chance of a return to Maunder minimum conditions within the next 50 years: the results presented here indicate that, despite hemispheric warming, Ireland, the UK and Europe could experience more cold winters than during recent decades", he added.

Sun Heading for a "Rest Period"

Last month, Irish Weather Online reported on research from the National Solar Observatory (NSO) and the Air Force Research Laboratory (AFRL) stating that a missing jet stream, fading spots, and slower activity near the poles say that our Sun is heading for a rest period.

The report concluded that the current sunspot cycle, Cycle 24, begins to ramp up toward maximum, independent studies of the solar interior, visible surface, and the corona indicate that the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or may not happen at all.

The results were announced at the annual meeting of the Solar Physics Division of the American Astronomical Society.

"This is highly unusual and unexpected," Dr. Frank Hill, associate director of the NSO's Solar Synoptic Network, said of the results. "But the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation."

Hill said, "this could be the last solar maximum we'll see for a few decades. That would affect everything from space exploration to Earth's climate."

Long range forecast for Winter 2011-2012

Meanwhile a UK-based long range weather forecaster last month issued a severe winter weather warning for 2011-2012. James Madden from weather organisation Exacta Weather claims to have correctly predicted the harsh conditions experienced over the last two years, and is once again forecasting record breaking snowfall and freezing temperatures during November, December and January.

One of Madden's primary methods of analysing long range weather conditions is his analysis of solar cycles. Commenting on the solar cycle, James Madden said: "Periods of low solar activity at present and what we have seen in recent years influence the Earth's atmosphere by allowing the stratosphere to cool. This has a somewhat more profound effect over Northern Europe and the UK in terms of colder and snowier winters, due to jet stream patterns that block warm air from reaching us and create more moisture."

winter ireland
© Enjoy in Ireland
Ice sheets flowing down the River Barrow on St. Stephen's Day 2010.
"Although sunspot activity has increased somewhat this year and there has been an increase in solar flare activity, the activity is minuscule in comparison to what it should be like during a solar maximum and in terms of frequency. Periods of low solar activity such as this have future repercussions of low solar activity in future cycles and produce extra cloud cover that reflects sunlight with a cooling influence on Earth. The lack of major sunspots and solar flares clearly indicate a slower conveyor belt within the sun. We are now in a very weak solar maximum and my observations indicate that the next solar cycle will also be weak", he added.

Commenting on La Nina and the Gulf Stream/North Atlantic Drift and their effect on our weather, Mr. Madden stated: "It is visible to see from recent NOAA satellite images that the Gulf Stream/North Atlantic Drift has drastically altered within the last few years. The Gulf Stream is basically a huge volume of heated water that brings warmth to the UK in terms of a mild atmosphere. This softens the climate we experience for the latitude we lie on. For example let's take Newfoundland who lie on a similar latitude to the UK, yet they experience much harsher winters as they do not benefit from this valuable heat source.

"La Niña is the cooling of the Pacific Ocean near the equator and influences changes to atmospheric pressure and wind changes. In terms of the UK this makes the jet streams in the North Atlantic stronger and therefore offers more precipitation in the form of widespread heavy snowfall during below average temperatures as cold easterlies dominate", he explained.

Mr. Madden also said that the dust and ash particles released by the recent volcanic eruption in Iceland and Chile would also contribute to cooling down of global temperatures. He continued: "Converted sulphur dioxide emissions from volcanic eruptions can also cause sunlight reflection in the atmosphere. "

He said he expected the 2011-2012 winter to follow a similar pattern in terms of how November and December was in 2010 for the vast majority of the coming winter.

"It will be exceptionally cold and snowy with well below average temperatures. I fully expect to see records broken with the highlands of Scotland being once again particularly hard hit. It is therefore vital to start preparing now in terms of high energy bills and raising awareness amongst the most vulnerable and elderly people of society", Mr. Madden concluded.

Are we in for a continuation of severe wintry weather in the coming years? Let us know what you think by posting a comment or emailing editor@irishweatheronline.com.

IRISH WEATHER ONLINE WINTER 2010-11 GALLERY