题目选项分析

According to scientists at the University of Alaska, while the surface temperature of the globe has risen over the last century by about one degree Fahrenheit, the surface temperature in Alaska, Siberia, and northwestern Canada has increased over the last thirty years by about five degrees.

According to scientists at the University of Alaska, while the surface temperature of the globe has risen over the last century by about one degree Fahrenheit, there was an increase in the last thirty years by about five degrees in Alaska, Siberia, and northwestern Canada.