National Geographic : 1972 Mar
of ground called permafrost, whose tempera ture always remains below 32° F. An obstacle to absorption, the zone measures 2,000 feet thick in parts of Alaska's North Slope and almost a mile deep in Siberia. For three-fourths of the year, the tundra is a frigid, hostile, seemingly lifeless realm. But in June a miracle begins. A never-setting summer sun brings forth plant species by the hundreds. Flowers ap pear-delicate, and often astonishingly color ful. Swans, ducks, and geese from the south splash down on pristine lakes. They mate and nest and head south again before autumn puts a slick of ice on every pond. The angry whine of mosquitoes mingles with a low-keyed hum of other insects. Herds of caribou cast long, stalking shadows as they wander across a sun-skirted horizon in search of favorite victuals. Lemmings scurry over the tundra and marshland as they seek food and try to avoid predators. Foxes, wolves, owls, and predatory jaegers make life for other animals a hazardous adventure. The cackling of ptarmigans adds a sound of urgency to this briefly burgeoning world. Moose and grizzlies, some of them with their young, wander along wooded streams and mountain valleys. Summer simply erupts in tundra country. It is a time for life; in this startlingly finite sea son, reproduction must counter winter's vio lence and death to keep nature in precarious balance. Then, as the first mantle of snow arrives, the smaller animals begin to disappear, bur rowing under the white surface in quest of enough shelter and food to endure the long winter. Some, like the ground squirrel, hiber nate; others, like the lemming, remain active in their snowy tunnels. Insect eggs, larvae, and pupae lie hidden in the soil. Nimble year rounders like the Arctic fox and ptarmigan change coats to match winter's whiteness (page 312). Thus they adapt to survive in a realm that has again become grim, treacher ous, deepfrozen. FOR CENTURIES the changing seasons of the tundra went unseen, except by Eskimos and an occasional explorer for what could draw man to a land as alien as this? What indeed? Petroleum prospectors dis covered in 1968 that the oil reserves under the permafrost on Alaska's North Slope were immense. They flew in to find ways to get the 304 oil out. Their proposal: an 800-mile pipeline to convey the oil, hot from the earth's depths, to an ice-free seaport far to the south.* Rugged as this land seemed, it was ex tremely fragile, and pipeline proponents had to take that aspect into account. Drive a bull dozer across the springy summer turf, and the tracks might remain for years. What would a hot pipeline do? To find the answer, another type of "pros pector" headed north-the natural scientist. Entomologists, botanists, mammalogists, per mafrost experts-they probed for facts to show how to protect the delicate tundra. Now I was on my way north to observe the results of their studies and to see for myself the miracle of Arctic summer. As a biologist I have long been fascinated by the adapta tion of living things to hostile environments, "Iseemed to sense, in these bravely aspiring bits of life, the plea for just a little more sun' and there are few environments as hostile as the tundra. An hour before, my jet airliner had cleared the traffic pattern at Fairbanks, Alaska, and crossed the Arctic Circle. The tortuous Yukon River had come and gone, then the forbidding, cloud-shrouded Brooks Range. For many minutes those vast Arctic plains called tundra slid unchangingly under the wings; then the plane began its descent to Deadhorse. As the plane banked downward, I pressed my face against the cool plastic window and studied the awesome expanse below. The ter rain was marked with strange patterns sug gesting cross sections of a giant beehive (pages 310-11). Innumerable mirrorlike ovals of standing water dotted the landscape. The notorious Alaskan mosquitoes greeted me when I stepped off the plane at Dead horse. So did a British Petroleum Company truck, whose driver took me to the company's *William S. Ellis reported on the pipeline last October in a NATIONAL GEOGRAPHIC article, "Will Oil and Tun dra Mix?"