The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future

Recent news reports about large holes in the ice and open waters at the Arctic Circle have prompted renewed concerns about the effects of global warming. In measured tones, however, geoscientist Alley reminds us that during the last 100,000 years or so the earth has experienced a wildly varied climate pattern. Using readings of ice cores taken from Greenland, where he participated for several years in the '90s in far-reaching research projects, Alley demonstrates that periods of slow cooling and centuries of cold have been punctuated by periods of sudden warming. In fact, he notes, climatic stability is the exception rather than the rule, and he contends that the unusually warm, stable climate we have experienced for the past 10,000 years is an anomaly. Through his study of the two-mile-long ice cores, Alley reveals a number of elements that contribute to global climatic changes: wind patterns, drifting continents and ocean currents. In lively prose, he illustrates that climate can be stable, but when pushed to change--by either human or natural forces--such change can occur more dramatically and at a faster rate than our industrial society has ever witnessed. Yet Alley is no alarmist in predicting the ways that human activities will affect climate and climatic changes will affect humans. Although not all scientists will agree with Alley's conclusions, his engaging book--a brilliant combination of scientific thriller, memoir and environmental science--provides instructive glimpses into our climatic past and global future that will appeal to readers interested in how our environment affects us. (Nov.)