THE ARCTIC IMPACTS OUR WEATHER The "polar vortex" events of early 2014, when frigid air descended into the continental United States,
demonstrate the direct impact the Arctic has on Northern Hemisphere weather. Because the Arctic is
warming twice as fast as the global average, the equator-to-pole temperature difference and sea ice
cover are decreasing, and these impact weather. The normally straight-flowing jet stream, which
separates the northern mass of cold air swirling counterclockwise (polar vortex) from more southerly
air masses, becomes wavier to the north and south, bringing icy Arctic air to mid-latitudes of the
United States, Europe, and Asia. Scientists are researching this weather pattern to see if it will result in
more frequent and longer-duration cold-air outbreaks. At the same time, an increasing number of
storms with greater rainfall and stronger winds is projected for Western Europe, and higher snowfall is
expected in Eurasia.
The author organizes the selection by -
a. explaining problems and supplying solutions
b. describing the polar vortex
C. listing effects of the polar vortex
d. describing causes and effects of the polar vortex.
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