Compared to other parts of the world, the atmosphere in the subtropical areas is warming faster. The effect is the maximum around regions 30 degrees north and south latitude. It is not just this! After scrutinizing more than 25 years of satellite data, scientists also found that jet stream in each hemisphere has pushed toward the pole. And this happened by about 1 degree of latitude, or 70 miles.
Scientists fear that this phenomenon could not only widen the tropics, but also expand some of the driest regions of the world. The warming band around 30 degrees north latitude crosses the southern United States, southern China and north Africa. The 30 degrees south latitude crosses southern Australia, South Africa and southern South America.
But, is the movement of jet streams the key evidence for global warming? Or is it just an anomaly? Though, John M. Wallace, a UW atmospheric sciences professor said that the work presentkly made cannot precisely explain why the jet streams are moving, he added that the long-term impact of this movement on rainfall could be serious.
Qiang Fu, a University of Washington associate professor of atmospheric sciences and lead author of a paper detailing the findings in the May 26 edition of the journal Science said, It is direct observational evidence of atmospheric circulation changes seen from satellites.
Via: Science Daily