Ice At The End Of The World: An Epic Journey Into Greenland's Buried Past And Our Perilous Future, Gertner - C

                              Greenland is the world's largest island - about three times the size of Texas. The ice sheet is 1500 miles long and almost 700 miles wide. It holds 3 quadrillion tons of ice.  This book studies its research and exploration over the last 150 years and  science's expectations for the future.                                                           Fritzhof Nansen, noted Norwegian explorer, scientist and later, diplomat, led the first team to cross the island in 1888. To access the ice sheet, they had to climb from the coast and cross a crevasse zone. The sheet peaked at about 8,000 feet above sea level. The team's success was heralded around the world and inspired Robert Peary to plan for a longer northern crossing. In 1892, Peary's party traveled from the west coast to the east and returned to their starting point on the northwest coast. He travelled a total of 1200 miles, wheres Nansen had only gone 350. He adopted as many Inuit practices as possible. He used reindeer sleeping bags and clothes and accomplished his mission with 20 sled dogs purchased from the Inuit. Twenty-years later, Knud Rasmussen and Peter Freuchen replicated Peary's trip as part of a long career of living amongst, studying and trading with the Inuit. In the 1930's a seismic test conducted with TNT estimated the ice to be 8,000 feet deep and predicted that if it melted, the world's oceans would rise 25 feet.  Moderns scientists with sophisticated equipment calculate that the estimate is off by a mere 8 inches.                                                                      After WWII, Paul-Emile Victor led a French team to the middle of the ice shelf to continue earlier explorations. Victor observed that the ice "was a recording machine of times and climate past." The French established a major camp and drilled the first deep ice core while eight men wintered the 1949-50 season there. They also learned from further seismic testing that the center of the island was actually below sea level. As the French continued their work, the US Air Force began to expand the WWII era base at Thule on the northwest coast, which was not far from Peary's original camp. "The advent of the Cold War and modern glaciology happened in tandem and happened at Thule." It was to be America's front line against the Soviets. To build bases, install radar installations and conduct operations on the island, it was necessary to understand how the ice moved and changed year to year.  In the 1950's, Air Force scientists concluded that the ice was in equilibrium. The summer melt was equal to the winter snowfall.                                                                                                                   Ascertaining past weather through the study of tree rings, ocean cores and ice cores came to the fore in the post-war era. In 1957, the US was able to drill 1350 feet. Nine years later, they drilled to 4450 feet and hit bedrock. Utilizing a mass spectrometer, US scientists were now able to determine the temperature on the day the snow fell, even if it was tens of thousands of years ago. As the strategic weapons of the Cold War shifted from bombers to missiles, the US scaled back at Thule, the money dried up and scientists had to find other funding. The Danes took the lead in Greenland and drilled to 6300 feet in the eighties. Simultaneously, deep drilling was pursued in Siberia and Antarctica. A decade later because of concerns about a warming planet, US and European teams drilled from the center of the ice pack 10,000 feet to the bedrock.                                                                                                                               The assumption that the ice sheet was in balance became less certain in the late 20th century. An analysis was conducted by the US using planes crisscrossing the island with a laser altimeter as a measuring device. The ice sheets around the world were clearly melting and adding volume to the world's oceans. Scientists did not know how to measure or estimate the pace of the melting, as both air and water temperature effect the melting. Greenland appears to be losing about 286 billion tons of ice per year. Greenland's ice melt may be slowed by the fact that the island is a bowl hemmed in all around by mountains. Greenland's glaciers flow through those mountain passes. It is expected that West Antarctica will melt first because a portion of the ice sheet is already over the ocean. Clearly, no one knows the future or if it will be decades, or hundreds or thousands of years before the ice melts, or if it can be slowed down. But, science is confident of at least a one meter rise in this century and that that will lead to the flooding of the world's coastal cities.