also says that snow bridges are melting rapidly, exposing crevasses.
“It looks like July around here,” he says, as I scribble down the information.
Crevasses.
Clinging to Mount Rainier’s flanks are twenty-six glaciers—giant rivers of ice slowly creeping downhill, replenished by the snow that pummels the summit all winter long. In a twelve-month span in the early 1970s, 1,122 inches of snow fell on Rainier. At the time, this set a U.S. record.
Rainier’s glaciers are complex geological formations, hundreds of feet thick, layer upon layer of ice of varying consistencies and thicknesses that can stretch for miles. The Emmons Glacier alone is comprised of an estimated 23.8 billion cubic feet of ice. Glaciers pack an unrelenting force, carving valleys and pulverizing boulders the size of houses. Thousands of years after they have receded, they will have left unmistakable imprints on the land.
The movement of glaciers is a simple matter of gravity. Once enough snow accumulates and hardens to ice, the combination of mountain slope and the gravitational force exerted on the ice layer begins pulling the mass downhill. Free water beneath the ice accelerates some parts of the glacier, while a rough bedrock base slows movement in other areas. The glacier’s different flow rates and directions open up tension cracks in the ice, called crevasses.
The top 150 feet or so of a glacier is under less pressure than the deepest layers, and so the shallow ice is more rigid—and more proneto fracturing under the enormous tension that builds up as the frozen mass unsteadily works its way downhill. Those ever-changing cracks can open slowly and later be concealed by snow and ice that freezes over the top of the slit. The process repeats itself innumerable times and is so insidious that a snow bridge a few feet thick can conceal a giant, yawning crevasse 10 feet across and 120 feet deep.
We have to prepare for the worst, so a couple of days before our flight, Mike shows up at the home Gloria and I share. On the lawn we uncoil a 165-foot length of Mike’s 8.8-millimeter climbing rope—the perfect kind for tackling glaciers. We are going to practice a crevasse rescue system that one of us on top of the glacier could use to extricate the other from a slot.
Though we have both done it before, we want to practice setting up a Z-pulley system. The arrangement rests on a simple principle: Dividing one long rope into three smaller sections, all threaded through pulleys, greatly increases one man’s leverage and lifting power. When rigged properly, the three sections of the rope form a giant Z. We practice for a simple reason: No matter what Hollywood movies suggest, no climber in the world can haul his partner back up a cliff, or out of a crevasse, without mechanical help.
We each know that if one of us plunges into a crevasse, the other must flop onto the ground and dig in with an ice ax to stop the fall. Then the climber atop the glacier will have a real chance to pull the other out with a Z-pulley lifting system.
So out there on the shaggy grass, we practice our backup system, just like Dad always taught me. On the mountain, our anchors will have to be ice screws and metal-bladed snow flukes buried securely in the glacier, but here in my yard we use a black walnut tree and the deck railing. Seventeen months ago, Mike spent a season in Antarctica, where he was on the McMurdo Sound search-and-rescue team that pulled two men and their load of dynamite from an enormous crevasse after their bulldozer crashed through a snow bridge.
Since he knows the details better, he leads me as we put together a Z-pulley. Then we take it all apart, and I do it on my own. Mike observes quietly as I feed the rope through carabiners and pulleys. Gloria stands behind him on the deck, grilling steaks for all of us. She watches and listens as we work with the rope, talking about different self-rescue scenarios.
“You guys seem to be putting a lot of effort
“It looks like July around here,” he says, as I scribble down the information.
Crevasses.
Clinging to Mount Rainier’s flanks are twenty-six glaciers—giant rivers of ice slowly creeping downhill, replenished by the snow that pummels the summit all winter long. In a twelve-month span in the early 1970s, 1,122 inches of snow fell on Rainier. At the time, this set a U.S. record.
Rainier’s glaciers are complex geological formations, hundreds of feet thick, layer upon layer of ice of varying consistencies and thicknesses that can stretch for miles. The Emmons Glacier alone is comprised of an estimated 23.8 billion cubic feet of ice. Glaciers pack an unrelenting force, carving valleys and pulverizing boulders the size of houses. Thousands of years after they have receded, they will have left unmistakable imprints on the land.
The movement of glaciers is a simple matter of gravity. Once enough snow accumulates and hardens to ice, the combination of mountain slope and the gravitational force exerted on the ice layer begins pulling the mass downhill. Free water beneath the ice accelerates some parts of the glacier, while a rough bedrock base slows movement in other areas. The glacier’s different flow rates and directions open up tension cracks in the ice, called crevasses.
The top 150 feet or so of a glacier is under less pressure than the deepest layers, and so the shallow ice is more rigid—and more proneto fracturing under the enormous tension that builds up as the frozen mass unsteadily works its way downhill. Those ever-changing cracks can open slowly and later be concealed by snow and ice that freezes over the top of the slit. The process repeats itself innumerable times and is so insidious that a snow bridge a few feet thick can conceal a giant, yawning crevasse 10 feet across and 120 feet deep.
We have to prepare for the worst, so a couple of days before our flight, Mike shows up at the home Gloria and I share. On the lawn we uncoil a 165-foot length of Mike’s 8.8-millimeter climbing rope—the perfect kind for tackling glaciers. We are going to practice a crevasse rescue system that one of us on top of the glacier could use to extricate the other from a slot.
Though we have both done it before, we want to practice setting up a Z-pulley system. The arrangement rests on a simple principle: Dividing one long rope into three smaller sections, all threaded through pulleys, greatly increases one man’s leverage and lifting power. When rigged properly, the three sections of the rope form a giant Z. We practice for a simple reason: No matter what Hollywood movies suggest, no climber in the world can haul his partner back up a cliff, or out of a crevasse, without mechanical help.
We each know that if one of us plunges into a crevasse, the other must flop onto the ground and dig in with an ice ax to stop the fall. Then the climber atop the glacier will have a real chance to pull the other out with a Z-pulley lifting system.
So out there on the shaggy grass, we practice our backup system, just like Dad always taught me. On the mountain, our anchors will have to be ice screws and metal-bladed snow flukes buried securely in the glacier, but here in my yard we use a black walnut tree and the deck railing. Seventeen months ago, Mike spent a season in Antarctica, where he was on the McMurdo Sound search-and-rescue team that pulled two men and their load of dynamite from an enormous crevasse after their bulldozer crashed through a snow bridge.
Since he knows the details better, he leads me as we put together a Z-pulley. Then we take it all apart, and I do it on my own. Mike observes quietly as I feed the rope through carabiners and pulleys. Gloria stands behind him on the deck, grilling steaks for all of us. She watches and listens as we work with the rope, talking about different self-rescue scenarios.
“You guys seem to be putting a lot of effort
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