30 years ago, I was a young lass very interested in geology, but even more at that point of my life, astronomy. I had spent many nights in my backyard, wrapped in multi-layers, squinting through a telescope, searching for the rings of Saturn and the moons of Jupiter. But 30 years ago today, Mt. St. Helens blew and for me, I awakened into a new perspective.
A few nights later, during a full eclipse, I hunkered in a nearby field with my telescope and I watched a blood-orange moon, tinted by the ash cloud, as it waned and waxed. I will never forget that night, as the air was heavy with dew and the quiet was disturbed only by the "ooh's" and "ah's" that formed my responses to the magic in the sky. How I wished I could've been there to see that ash
Now, I long to simply go and see this volcano, but regardless of my future travels, I have made additional arrangements. After my life is over, my ashes will rest on that volcano; I have very dependable friends who will do this for me. Is this macabre? No. It's ensuring that the next time Mt. St. Helens blows, part of me will be right on top of the situation. :)
Lin
30 years after Mount St. Helens blew, the volcano reveals its secrets
May 15, 2010, 5:17PM
Torsten Kjellstrand/ The OregonianHundreds of people crowded the Coldwater Ridge Visitor Center on a Sunday afternoon in early May, 2010. Emily Dehne of Portland and her friend Casey Levin of St. Louis played a card game while waiting for an eruption of Mount St. Helens. Levin was in Portland to visit Dehne, when the two decided to drive up to the visitor center.A sudden series of earthquakes at
Mount St. Helens caught scientists by surprise in March 1980. Less than a week after the quakes began, a blast of steam and ash opened a small crater at the summit of the reawakening volcano.
Geologists didn't know enough to give public safety officials a clear picture of the danger.
"They wanted us to tell them what the earthquakes meant, and I had no idea," says Steve Malone, the University of Washington professor who led the seismic monitoring. "All I could tell them was there's a lot of earthquakes, and something's coming."
Photos: Mount St. Helens
Photos from the Oregonian archive
Mount St. Helens 2010
At 8:32 a.m.
May 18, 1980, a magnitude 5.1 earthquake triggered an enormous landslide. The entire north side of the mountain collapsed, releasing a furious sideways explosion that swept away forests in an arc of devastation for miles to the north. Within minutes, a column of volcanic ash reached 15 miles above the Earth. The volcano pumped out ash for more than nine hours, darkening the skies for more than 100 miles.
The world changed. Fifty-seven people died in the eruption. Devastation stretched for 230 square miles. Mudflows disgorged by the volcano swept down rivers, wrecking 27 bridges and 200 homes. Sediment filled shipping channels in the Columbia River, cutting off ports for days as dredgers worked to clear the rivers. Ash pumped into the upper atmosphere circled the Earth in 15 days, lowering global temperatures.
But in the 30 years since the catastrophe, the volcano also has proved to be a powerful force of regeneration. Ongoing eruptions are rebuilding the mountain and revealing to geologists the hidden workings of volcanoes. Plants and animals moving into the blank landscape are showing biologists the resilience of life and emergence of ecosystems. Here are 15 ways the mountain changed human understanding of the world:
VITALIZING DISTURBANCE: The moonscape around Mount St. Helens didn't remain barren long. Pockets of survivors and wandering newcomers seized the opportunity to claim real estate no longer dominated by towering trees. Fallen logs provided nesting and foraging sites for birds, cover for rodents, and carbon and nutrients as they decomposed.
Lupine flowers -- carried as seeds by rodents, winter runoff and wind -- colonized the pumice plain. Able to fix nitrogen from the air, lupines fertilized the soil, which helped other plants establish.
Inside the 110,000-acre
National Volcanic Monument established in 1982, the
U.S. Forest Service has allowed recovery to proceed at its own pace.
"One of the biggest lessons is the recognition that these large, slowly regenerating areas are very important ecologically but they are quite rare," says Charlie Crisafulli, a Forest Service ecologist. Allowing lands to recover on their own can lead to more biologically diverse, productive and stable ecosystems.
"After a severe natural disturbance, our tendency is to try and go in and fix it," he says. "But oftentimes the effort of restoration is not warranted. Nature is quite good at resilience."
PROFUSION OF PONDS: Ponds numbered about 30 before the eruption, but increased to 150.
MARCH OF THE TOADS: Frogs and salamanders, rapidly declining in many places worldwide, are booming. Twelve amphibian species survived in the blast area protected in ponds. Additionally, red-legged frogs, Pacific tree frogs, Western toads and Northwestern salamanders traveled miles of barren debris to reach new ponds and establish large populations.
PARATROOPING SPIDERS: Spiders colonized the new habitat by ballooning, that is, using threads of silk to float with the wind. They landed at a rate of more than 100 per square meter over one summer, some from as far as 30 miles away, scientists from Seattle's
Burke Museum and the University of Washington found. Most of the paratrooping spiders quickly died in the harsh environment, but by 1986, six species had established breeding populations on the pumice plain.
HYPERACTIVE VOLCANO: In little more than 500 years -- a blip in geological time -- Mount St. Helens has produced four catastrophic blasts. Two of the historic major eruptions hit within two years, 1480 and 1482, proving that the volcano can quickly recharge. Another explosive eruption in our lifetimes isn't out of the question.
"It wouldn't surprise me," says Seth Moran, a seismologist at the U.S. Geological Survey's
David A. Johnston Cascades Volcano Observatory, who points out that a dozen other volcanoes in the Cascade Range also could erupt.
UNCORKED AVALANCHE: Before 1980, volcanologists didn't realize how often landslides factor into the most destructive volcanoes. They quickly learned that avalanches, or "flank failures," have been common at steeply sloped volcanoes around the world, which explains landslide deposits alongside ancient volcanoes. In flank failure, the sudden removal of the upper part of the volcano lets lose an explosive expansion of pent-up gases dissolved in pressurized, superheated magma, or molten rock. It's like popping the cork on champagne.
RISK TO AIRPLANES: Millions of travelers learned about the threat of volcanic ash when an eruption in Iceland forced airlines to ground European flights for five days in April. But Mount St. Helens gave the aviation industry its first wake-up call. On the first day of the 1980 eruption, one jetliner couldn't avoid the spreading ash cloud and sustained severe engine damage. A week later, a C-130 pilot unknowingly flew through an ash plume that killed the plane's turboprop engines. After a harrowing plunge, the pilot regained power and landed safely. It was the first documented case of engine failure caused by volcanic ash -- but not the last. Three commercial airliners had engine-stopping run-ins with volcanic ash in 1982 and 1989.
NEVER-ENDING MUD: To keep rivers clear of volcanic mud, the federal government has spent more than $10 billion. But the mud keeps coming down the
North Fork Toutle River, posing an increasing flood hazard downstream in Castle Rock, Kelso and Longview. Sediment transport levels are 10 to 100 times pre-eruption levels.
In the avalanche that uncorked the 1980 blast, most of the mountaintop spilled into the North Fork Toutle River Valley, leaving a practically inexhaustible supply of mud. Sediment reaches the Cowlitz River, settles and decreases the channel depth, making it easier for floods to rise above banks and levees.
The
U.S. Army Corps of Engineers built an 1,800-foot long, 184-foot high sediment-trapping dam across the river in 1988. But ongoing loads are overwhelming it, and in 2007 the corps resumed dredging downstream. Silt and gravel flats stretch for miles above the dam, scoured clear of vegetation by winter and spring floods. In a pilot project scheduled to get under way this summer, the corps will try to slow the sediment by creating a more stable, winding river channel above the dam. Engineers will build artificial islands armored with fallen trees and other structures to create stable banks to define the channel and allow shrubs and trees to root and build anchoring habitat.
LIMITED WARNING: Volcanoes presumed inactive can come to life very quickly. At 2 a.m. Sept. 23, 2004, seismometers detected the first of hundreds of slight earthquakes. Eight days later, an explosion of steam and ash blasted a new hole in the crater -- marking the beginning of eruptions that continued until 2008. Seismologists monitoring the volcano were surprised by the reawakening because earthquake activity had dropped to unusually low levels during the previous four years.
The 2004 eruption made clear the importance of having monitoring networks in place ahead of time, says Moran of the Geological Survey. "Having stations in ahead of time enables you to see things that you otherwise would not have seen, detect unrest earlier, and interpret it better."
EDUCATED GUESS: Scientists are now better able to detect when a sleeping volcano is preparing to erupt. Three days after the earthquake swarm in 2004, geologists issued a "Notice of Volcanic Unrest," giving advance warning of steam and ash explosions that soon followed. Volcanologists said that magma, could reach the surface and shoot substantial amounts of ash into the air, but noted that lava flows or mudslides posed no threat to towns or dwellings. Those warnings proved accurate.
MILLIONS OF EARTHQUAKES: During the 2004-08 eruption, scientists collected information on 2 million earthquakes from the volcano -- enough data to keep researchers busy for years.
SEISMIC DRUMBEATS: Seismic monitoring revealed a drumbeat pattern that scientists began to recognize at many other volcanoes around the world. "At Mount St. Helens, they lasted for months and months, and that's never been seen at a volcano before," says Moran. Volcanologists have two competing theories about the drumbeat earthquakes: They may emanate from rising magma as it slips and then sticks against surrounding rock, or they may arise as underground cracks release expanding steam and gas, refill, then release more steam and gas.
REBUILDING THE MOUNTAIN: Within a week of the opening blast in 2004, magma raised a rocky mound 30 stories high, eight city blocks long and six blocks wide. The fast-growing dome inside the crater amassed millions of cubic yards per day. By 2007, the rock dome rose higher than the Empire State Building and contained enough lava to fill Portland's Rose Garden 163 times. But when the dome-building eruption ended in 2008, Mount St. Helens had added only about 7 percent of the material it lost in the 1980 landslide and eruption. Regaining its former size may take a few hundred years, as it did after an eruption 2,500 years ago that destroyed its cone.
MAGMA CLUES: Samples of magma from the latest eruption offer clues about its source. Its chemical signature, similar but not identical to magma expelled from 1980 to '86, suggests that magma left over from the 1980s, partially depleted of dissolved gases, drove the recent eruption. The slight chemical difference could mean that the eruption tapped a different part of the reservoir under the volcano, or that an injection of magma from farther below added some fresh material to the mix.
MYSTERIOUS PLUMBING: Attempts to zero in on the source of the molten rock have failed. Seismologists have used increasingly sophisticated tools -- comparable to CAT scanners -- to look for magma chambers underground. They speculate it may mean that little magma is stored beneath the volcano, at least down to the 5-mile range of current probes.
"It is hands down the best-studied volcano in the Cascades," Moran says. "Yet in some ways because of that, we've only raised more questions about it."
--
Joe Rojas-Burke
Sources: Daniel Dzurisin, a geologist at the U.S. Geological Survey's David A. Johnston Cascades Volcano Observatory; Charlie Crisafulli, U.S. Forest Service ecologist; Rodney Crawford, spider expert at Seattle's Burke Museum; Seth Moran, a seismologist at the Cascades Volcano Observatory; Jon J. Major, a research hydrologist with the U.S. Geological Survey
Source Two PBS programs mark Mount St. Helens anniversary with looks at eruption and aftermath
May 15, 2010, 10:59AM
Jutta Wirth, Interspot FilmNOVA's "Mount St. Helens: Back From the Dead" focuses on the surprising life that has sprung up in the "dead zone" around the volcano since its 1980 eruption.The historic explosion of Mount St. Helens 30 years ago (read
The Oregonian's full coverage of the anniversary) is a snapshot moment, still, for tens of thousands of Northwesterners. We clearly recall where we were, what we were doing and how we reacted on May 18, 1980, when we learned that the theoretical eruption was suddenly cataclysmic reality.
What grabbed nearly all of us was the unanticipated scale of the devastation. For two months St. Helens had rumbled; spouted tall, thin clouds of steam and ash from its peak; and attracted visitors. Perhaps it could simmer away like that for years or maybe have a larger, more interesting eruption that could be really good for tourism.
But Ma Nature had other plans -- a 200-square-mile dead zone created in hours, along with floods of water, mud and debris that would have been disaster enough without a volcano.
A succinct survey of what happened 30 years ago and what is happening now will play Tuesday on
OPB with
"Mount St. Helens: Back From the Dead," a
NOVA documentary. Michael Lienau's partly autobiographical 1994 documentary,
"The Fire Below Us," will follow.
"The Fire Below Us" They are a fine, informative pair, although they ideally would be seen in reverse order. "Fire" tells the tale with news and documentary footage from 1980 and dramatizes the stories of several survivors -- and a few victims. Lienau presented previously unseen footage in 1994.
Horrific as it was, the eruption could have been incalculably worse. At 8:32 a.m. on a Sunday hundreds of loggers and others were not working in the area. One day later they would have been, as they had been on Friday.
Lienau summarizes the now-astounding lack of preparation on all levels: Evacuation routes, air surveillance, emergency communications channels, emergency vehicle and equipment allocation, coordination of emergency agencies -- these and other measures possibly hadn't even been discussed.
One fact is brilliantly clear in both films: Not only did few warn, on the record, how astounding an eruption could be, but many argued that the designated danger zones were Chicken Little panic measures and that the restricted zones were business killers. Crusty coot Harry R. Truman, 83, became a color character on the nightly news for refusing to leave his Mount St. Helens Lodge on Spirit Lake. Of the 57 killed by the blast, only four were in the restricted zone.
As with Pearl Harbor, the Kennedy assassinations, 9/11 and other disasters, everything is brilliantly clear after the smoke clears.
Lienau found God. He was 20 and hoping to become a filmmaker, so he eagerly accepted the chance to be on the film crew around the now-calm volcano on May 23, a three-hour gig. Three days later, after a second eruption, afflicted by hunger, thirst and pain, he feared he was dying and prayed. A clear voice told him where to look, he says, saving him and the rest of the crew.
"Back From the Dead" The title emphasizes the amazement felt by so many that the dead zone is now teeming with life, since it was expected to be dead for decades. Scientists in many fields explain and show how the surprise happened. A principal point of "Back From the Dead" is that, catastrophe though it was, the eruption created an ideal research lab.
A biologist discovers that gophers far enough underground survived. Their feeding habits turned out to be lifesavers. In Lienau's film a Weyerhaeuser forester says the company planted 45,000 firs; far from just starting, they thrived.
And the volcano itself is a living being. Through seismographs, time-lapse photography and other methods, scientists show how the mile-wide crater keeps changing. We learned some new words, like "dome-building." St. Helens lost 1,300 feet off the top. It is getting it back.
Both film stress the obvious: St. Helens will erupt again. But when?
Another fascinating lab report from the crater: A volcanologist cheerfully explains how the eruption exposed strata levels revealing 16,000 years of Mount St. Helens' history in impressive detail. Turns out it blows its top about every 1,000 years. About. Roughly. And many were at least 10 times more powerful than the 1980 blast.
But wait. St. Helens erupted in 1479 and 1482. Not even close to 1,000 years. It just decided to blow after three. Both blasts were among those way worse than in 1980.
Oh, yeah, and Hood, Rainier, Adams, Shasta -- they've blown before. They'll do it again. Nothing else is possible.
Here's my snapshot memory: St. Helens' roar hit Salem, parts of Idaho and other locales within 220 or so miles, yet not parts of Portland. It was a study in acoustics and topography.
I was in a weekend drill at the Naval Reserve Center under the bluff by the University of Portland. Heard zip. But guys with radios spread the word, so at lunchtime my five-man unit drove north on Interstate 5 to see the spectacle. But we were disappointed.
High, dark clouds obscured the whole sky, horizon to horizon, so we saw nothing. Finally, we got it: The horizon-to-horizon cloud was Mount St. Helens'.
--
Ted MaharSource
SEE IT ONLINE HERE
--
(Gars O'Higgins Station penguins)
http://wiinterrr. blogspot. com/http://penguinnewst oday.blogspot. com/http://penguinology .blogspot. com/(Twilight Saga commentary)
http://throughgolde neyes.blogspot. com/(Coming soon---Volcano Watch!)
One does not discover new lands without consenting to lose sight of the shore for a very long time.
-- Andre Gide
>^,,^<
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