Looming high above and beyond the alpine coniferous treeline, the massive bulk of Mount Rainier hosts thick, active glaciers. These slabs of ice flow, crack, tumble, and otherwise push inexorably down the steep slopes of the big volcano, carrying with them strips of embedded rock and gravel scoured off the mountain. It’s no surprise Rainier wears such a thick veneer of ice, as it thrusts over 14,000 feet skyward into uninhibited fetches of cool, moist Pacific winds, wringing out hundreds of inches of snow per year. It also shouldn’t be surprising that, when even minor eruptions melt and loosen some of this ice, disastrous lahars (fast-flowing slurries of ice, water and rock) sweep down toward Puget Sound, burying everything in their path. The sediment record around the southern sound is full of Rainier’s lahar layers, and tells a story modern emergency-preparedness efforts must heed.
15 S Greenwater WA (13 Aug 16) Looking SW
46.9122, -121.6147
Glacial Breaks
Looming high above and beyond the alpine coniferous treeline, the massive bulk of Mount Rainier hosts thick, active glaciers. These slabs of ice flow, crack, tumble, and otherwise push inexorably down the steep slopes of the big volcano, carrying with them strips of embedded rock and gravel scoured off the mountain. It’s no surprise Rainier wears such a thick veneer of ice, as it thrusts over 14,000 feet skyward into uninhibited fetches of cool, moist Pacific winds, wringing out hundreds of inches of snow per year. It also shouldn’t be surprising that, when even minor eruptions melt and loosen some of this ice, disastrous lahars (fast-flowing slurries of ice, water and rock) sweep down toward Puget Sound, burying everything in their path. The sediment record around the southern sound is full of Rainier’s lahar layers, and tells a story modern emergency-preparedness efforts must heed.
15 S Greenwater WA (13 Aug 16) Looking SW
46.9122, -121.6147