Last month was the warmest August globally since records began 130 years ago. Data by NASA shows that August 2014 experienced global highs 0.70°C above the 1951-1980 temperature average.
However, the difference is small compared with previous warm Augusts, including that of 2011, 2008, 2006 and 2003. The second warmest August was 0.69°C. in 2011 followed by 0.68°C in 1998 and 0.66°C in 2006. While this year has been exceptionally warm, NASA has warned against reading too much into a single month’s records.
Scientists had predicted extreme weather events to surface earlier this year after it looked like an El Niño event would develop in the Pacific Ocean. El Niño refers to a set of conditions when the surface of the sea in an area along the Equator in the central and eastern Pacific Ocean becomes hotter than usual.
The average water temperature in that area is typically between 1 and 3°C (around 2 and 5°F) warmer than normal during this event. This has the effect of adding huge amounts of heat and moisture into the atmosphere, ultimately affecting patterns of air pressure and rainfall across the Pacific and globally.
Greg Laden wrote in Science Blogs: ‘We don’t know how 2014 will rank as a year. If there is no El Niño it will rank high. If an El Niño gets going soon enough to affect the year’s average, 2014 may well be in the top few warmest years since global warming began.’
But warmer weather in some parts of the world could trigger a freeze elsewhere. In a separate study, researchers discovered a link between rising ocean temperatures, and a large pocket of cold air known as the polar vortex. They found that as oceans heat up and melt the Arctic ice, warm air is released that destabilizes polar air and sends cold blasts into the atmosphere. The polar vortex was responsible for the extreme and freezing temperatures experienced in the US last winter.
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