Excruciating Weather Bouts- Polar Vortex

 

Polar vortex has become latest buzz word ever since estimated 187 million people have been reeling under the spell of record low sub freezing temperatures ever recorded in several parts of United States of America. Nearly all the states from mid west to South east and north east are reeling under the life threatening cold as the National weather service has described it. Life was thrown out of the gear as thousands of passengers have been stranded since flights operating in these regions have been cancelled, schools are closed and business establishments have been shut down. People were advised to stay indoors as much as possible to avert the frost bites and hypothermia. This anomalous weather conditions are fall out of the Polar Vortex.

Polar vortex also termed as Polar Cyclone hover near the poles year long. They are weaker in summer and strongest in winters.  Basically it is a whirl wind of extremely cold and extremely dense air moving in the counter clockwise direction over the low pressure area near the poles. These winds usually reach a speed of 160 kmph and keep the cold air locked up at the poles. But when the cyclones are weak, the winds break up, and spills over to the South bringing with it Arctic temperature. In the present case, the entire Arctic vortex has tumbled down south resulting in freezing temperatures. The Arctic vortex is elongated in shape with two centres in the northern hemisphere, one in the Baffin Islands of Canada and the other over north east Siberia. In Southern hemisphere it is located in the Ross Ice Shelf.

 Studies conducted in 2001 have suggested a link between the extreme weather conditions and polar vortex and identified interactions with the decline of the Arctic sea ice, reduced snow cover, evapotranspiration and North Atlantic Oscillations. These observations are considered preliminary as the conclusions are based on the data of previous 13 years which is termed to be insufficient in Climatological study. Climatology observations are usually based on the comparisons of data over several decades.

As per the existing view, snow at the polar caps reflects the sunshine but as the sea snow declined, water started absorbing sunlight resulting in increase of levels of evaporation and transpiration and substantial warming of the Arctic region, twice as faster as the rest of the planet. The jet stream or the fast blowing westerly winds which act as a boundary between the cold northern polar air and the warm southern air is essentially preventing the entry of the Arctic winds down south. But as the temperature difference between the northern polar and the southern tropical regions narrow down, the jet stream weakens making it more likely for the cold Arctic air to move to southern latitudes. Some scientists view that an unusually large kink in the jet stream might have led to escape of the Arctic air further down south. This Polar vortex can lead to major cold out breaks in any portion of Northern Hemisphere- North America, Europe and Asia. This might result in cold snaps in multiple locations. The temperature fall was to a tune of 25 to 35 degrees below the average over large swaths of the Midwest. This kind of extremely frigid temperature was earlier recorded in winter 1985 Arctic outbreak.

Climatologists believe that warmer than average temperatures in the Arctic regions can weaken the Polar vortex resulting in colder than average temperatures in the lower latitudes. Perhaps, weakening of the polar vortex might have been the reason for the extreme winter of 2009-2010 which brought record snow to regions of Northern Europe, eastern Asia and eastern North America. Polar vortices in the Antarctica are the reason for winter weather in Southern hemisphere and have resulted in conditions responsible for depletion of the ozone layer as well.

This phenomenon is largely the offshoot of the rapid warming and loss of the sea ice in the Arctic largely due to the manmade climate change. Arctic warming is altering the heat balance between the poles and the equatorial regions with the result extreme weather conditions have become more common. While North America is reeling under the subfreezing temperatures regions across Arctic, Scandinavia, Europe and Asia have recorded above average temperatures. This kind of situation referred to as Arctic Paradox or Warm Arctic, Cold Continents was first identified by some researchers several years ago. Now the global warming is becoming global weirding plunging continents into occasional deep freeze. It might be surprising but true that Fairbanks in Alaska is jealously warmer that Georgia or Alabama.

Further Climate reports of the TIME magazine has predicted the year 2014 to be one of the warmest years of the earth. The other three warmest years on record are 1998, 2005, 2010 and all of these were El Nino years. El Nino in Spanish means “the boy” and it occurs when the surface ocean waters in the South Pacific Ocean becomes abnormally warm which develops over the western coast of South America and cause climate change across Pacific Ocean. Since the Pacific Ocean covers 30% of the planet’s surface any additional energy generated by its warming can tip off major weather changes around countries of the world. This type of anomalous weather situations occur at irregular intervals of two to seven years and lasts for nine months to two years. The average period of occurrence is five years. When the warm conditions prevail for seven to nine months they are classified as El Nino Conditions and if it occurs for more than nine months they are called El Nino Episodes. El Nino has a counterpart La Nina means little girl during which the sea surface temperature across equatorial eastern central Atlantic Ocean is lower than normal by 3-5C. El Nino is not always followed by La Nina.

El Ninos often result in abnormally dry conditions in South East Asia and Australia and weakening of Indian Monsoon. They can also result in extreme conditions in North and South America while Southern Africa experiences drought. Even the marine life is drastically affected, El Nino reduces the upwelling of the cold nutrient water which supports the large fish populations and the warm oceanic waters can destroy the corals. Hence the impact on the world fishing economy would be serious.

The consequences of a strong El Nino’s can be devastating ranging from serious outbreak of tropical diseases to higher rates of civil war as recorded in the year 1997-98. Research has suggested that powerful El Nino that occurred between 1789 to 1793 devastated crop yields in Europe and might have triggered the French revolution. In fact, the year 2013 which had no El Nino had extreme weather conditions with unusually high amounts of rains and hot summers, an sign of increasing global warming. But climatologists expect that South Pacific waters might heat up to at least 0.5 C higher than average for three months to be an El Nino and predict that year 2014 might be a record breaker on all fronts. Undeniably the affects of global warming which is entirely man made are leaving their trail of destruction on the mankind and sending warning signals across to curtail the scrupulous destruction of the Mother Nature.

 

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