The fringes of the coldest continent are starting to feel the heat, with the northern Antarctic Peninsula warming faster than virtually any place on Earth. These rapidly rising temperatures represent the first breach in the enormous frozen dome that holds 90 percent of the world’s ice. by fen montaigne In 1978, when few researchers were paying attention to global warming, a prominent geologist at Ohio State University was already focused on the prospect of fossil fuel emissions trapping heat in the Earth’s atmosphere. His name was John H. Mercer, and when he contemplated what might be in store for the planet, his thoughts naturally gravitated to the biggest chunk of ice on Earth — Antarctica. “If present trends in fossil fuel consumption continue…” he wrote in Nature, “a critical level of warmth will have been passed in high southern latitudes 50 years from now, and deglaciation of West Antarctica will be imminent or in progress… One of the warning signs that a dangerous warming trend is under way in Antarctica will be the breakup of ice shelves on both coasts of the Antarctic Peninsula, starting with the northernmost and extending gradually southward.” Mercer’s prediction has come true, and a couple of decades before he anticipated. Since he wrote those words, eight ice shelves have fully or partially collapsed along the Antarctic Peninsula, and the northwestern Antarctic Peninsula has warmed faster than virtually any place on Earth. The question as humanity pours greenhouse gases into the atmosphere at an accelerating rate, is not whether Antarctica will begin to warm in earnest, but how rapidly. The melting of Antarctica’s northernmost region — the Antarctic Peninsula — is already well underway, representing the first breach in an enormous citadel of cold that holds 90 percent of the world’s ice. Much attention has rightly been paid to the precipitous warming of the Arctic, where Arctic Ocean ice is rapidly shrinking and thinning, Greenland’s large ice sheets are steadily melting, and permafrost is thawing from Alaska, to Scandinavia, to Siberia. But none of the earth’s ice zones, or cryosphere, can compare with Antarctica, which is 1
