North of the Canadian forests, a series of boreholes in Alaska revealed soil temperature increases of 2 to 5 degrees C. (3.6 to 9 degrees F.) during this century. Researcher David Deming noted in an article in Science, in June, 1995, that while such increases in underground temperatures are not proof of atmospheric warming, it does appear the most likely of all possible causes. "The solid Earth...continuously filters out daily and seasonal changes in ground surface temperatures while maintaining a running record of the longest mean...The sum of evidence is consistent with theoretical predictions of warming related the accumulation of greenhouse gases in the Earth’s atmosphere from [human] activities..." Deming’s findings parallel a discovery the previous December that a deep layer of the Arctic Ocean has warmed by 1 degree C. in the last few years. Around the same time, scientists at the National Oceanic and Atmospheric Administration (NOAA) discovered that surface temperatures at 9 stations north of the Arctic circle have increased by about 5.5 degrees C. (9.9 degrees F.) since 1968.
Citations: "Climatic Warming in North America: Analysis of Borehole Temperatures," Science, Vol. 268, June 16, 1995. Also: "Listen up! The World’s Oceans May Be Starting to Warm," Science, Vol. 268, June 9, 1995. See also