Meet the world s newest glacier at Mount St. Helens

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1 Meet the world s newest glacier at Mount St. Helens By Seattle Times, adapted by Newsela staff on Word Count 733 Hikers walk past this chunk of the volcano that existed before May 18, The Crater Glacier surrounding the lava dome is growing at a time when most glaciers around the globe are in rapid retreat. Photo: Mike Siegel/Seattle Times/TNS SEATTLE Ray Yurkewycz perched on the rim of Mount St. Helens. He marveled at the ancient forces still at work in the Northwest's most restless volcano. Rocks and boulders slid off the crater walls, kicking up dust. Steam rose from the twin domes formed after Mount St. Helens big eruption in But Yurkewycz, who is the operations director for the nonprofit Mount St. Helens Institute, was focused less on the volcano s fiery past than its icy present. Few people realize, he said, that the hollowed-out crater now holds the world s youngest glacier. Crater Glacier is also growing at a time when most glaciers around the globe are shrinking.

2 It s cascading down into this valley now, Yurkewycz said, pointing out a tongue of ice flowing over a rise and into a rocky ravine. It s only been in the last two years that it started doing that. Face To Face With The Newest Glacier Yurkewycz led a small hiking group to the north ridge late last month. They were treated to a rare, close-up view of the glacier. On the volcano s north side, where the 1980 blast occurred, the U.S. Forest Service limits access to the public. Not only are the rugged upper slopes dangerous, but the area serves as an open-air laboratory for scientists tracking the area's recovery. The guided hike allows visitors to scramble off-trail to the glacier lookout. Mount St. Helens Institute began the outing three years ago. It will offer nine hikes this year, beginning in late July. At $195 per person, critics say it is too expensive. They want people to have greater freedom to hike the entire 110,000-acre Mount St. Helens National Volcanic Monument. Scientists at the U.S. Geological Survey s (USGS) Cascades Volcano Observatory have been visiting the area since the early 1980s. They have recorded the unique conditions that led to the glacier s formation and its stunning growth. Nothing about this glacier is typical, USGS scientist Steve Schilling said.

3 And A Baby Glacier Was Born Before 1980, Mount St. Helens was shaped like a cone and was surrounded by a dozen small glaciers. Most were destroyed during the eruption. The mountain s north side collapsed, unleashing the biggest landslide ever recorded. The blast wiped out everything for miles around and destroyed 230 square miles of forest. When the dust and ash settled, a horseshoe-shaped shell of a mountain was left. That shell provided a perfect nest for a baby glacier. The shell faces northward, which helps shield snow from the sun. A thick layer of volcanic rock on the crater floor blocks the volcanic heat from below. A lava dome formed an area where snow could pile up. By 1988, a permanent snowfield more than 200 feet thick lay in the crater. It Was A Weird Icy Hot Year But things really got weird in That is when the volcano sputtered back to life. It alternately spit steam and oozed thick, pasty lava for several years. The magma quickly built a new dome more than 1,200 feet high. The USGS team feared the heat would melt the glacier and send water and mud rampaging through the valleys below. But the ice was so well protected by the rock layer that very little melted away. Now, the glacier is creeping farther down the valley. A steady stream of meltwater springs from the base of the glacier, watering trees and flowers below. The ice is about 650 feet thick in places, said USGS geologist Dave Sherrod. Measured in a straight line, the glacier is 1.25 miles long. The surface is so covered with volcanic rock that only a few glints of blue ice can be seen. In fact, Schilling thinks nearly one-third of the glacier is rock. It s pretty exciting, Sherrod said. You can have rocks the size of a Volkswagen being hurled down at you. Exploring The Steamy Wonderland Poisonous gas occasionally drifts from the lava dome. The interior of the glacier is full of caves. A group of expert cave mappers got permission last year to explore those caverns for the first time.

4 They rappelled in through a funnel-shaped mouth they called the Godzilla Hole, said Jared Smith. He is the lead guide for the Mount St. Helens Institute. It s probably 80 or 90 feet straight down, Smith said. Inside, they found a steamy wonderland of sculpted ice and tunnels. It s just totally beautiful.

5 Quiz 1 Which of the following details is MOST important to include in a summary of the article? (A) A guided hike to Crater Glacier costs $195. Cave mappers have recently explored the glacier. The Crater Glacier has qualities that make it unique. Streams flow from the glacier and water plants growing below. 2 What would be another good title for the section "And A Baby Glacier Was Born"? (A) "A Blast Of Ash" "Ideal Conditions" "Largest Landslide" "North-Facing Shell" 3 Based on the article and the graphic "How to grow a glacier," when did the snow in the crater become constant? (A) Which section of the article is NOT represented in the graphic "How to grow a glacier"? (A) Introduction [paragraphs 1-5] "And A Baby Glacier Was Born" "It Was A Weird Icy Hot Year" "Exploring The Steamy Wonderland"