It is known that early man tried to live at the Tibetan Plateau, also called as the 'roof of the world', around 20,000 years ago. It region has...
US scientists suspect longer and colder winters over North America and northern Europe because of warmer Arctic conditions. They believe that rising temperatures of the Arctic could lead to permanent change in high-altitude polar jet streams that flow in the northern altitudes from west to east.
Scientists have found a direct link between temperature and the speed of jet streams. As the high-altitude jet streams are formed when cold Arctic air strikes with warmer air from South, researchers suggest that higher the difference in temperature more will be the speed of jet streams.
Melting of polar ice caps has warmed the Arctic air in the recent years, said Jennifer Francis, a climate expert at Rutgers University at the American Association for the Advancement of Science meeting (AAAS).
She said that ice caps acting as lid on the oceans separate oceans from colder atmosphere in the Arctic region, but the removal of the lid makes the Arctic air warmer.
Francis cited an example of Alaska which experienced warmest temperatures for the first time during this winter season. Also, for the first time ever in recent history, volume of sea ice in the Arctic has been recorded at one of the lowest levels.
James Overland, weather expert with the National Oceanic and Atmospheric Administration (NOAA), said that the temperatures in the Arctic are increasing twice or thrice the speed than rest of the planet.
Mark Serreze, Director of the National Snowland Ice Data Center in Boulder, Colorado, claims that the jet streams, also called as ‘Santa’s Revenge’, can cause harmful impact on agriculture, especially in farm-rich middle-latitudes in the US.