Living with volcanoes

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When it comes to the geology- and climate-changing forces of volcanoes, humans don’t have much direct experience. There have been some major eruptions that have been observed by humans, but the majority of information that we have comes from studying the geological evidence left behind. Geologists who study such phenomena discover much about the history of the planet. That knowledge doesn’t translate into abilities to predict the future.

The Yellowstone Caldera, sometimes referred to as the Yellowstone Supervolcano, is one of the largest volcanic caldera in the world. It measures 43 by 28 miles. I grew up on Montana just north of the region of the volcano. In addition to all of the geothermal features of Yellowstone National Park, hot springs are common in the surrounding area, including two that we regularly visited within a few miles of my hometown.

The 1959 Yellowstone Park earthquake was a major event for all folks who lived near Yellowstone at the time. We could feel the shaking in our home and providing airplanes for observation and rescue coordination was a major focus of our family business at the time. Engineers and geologists from around the world came to study the effects of the earthquake and plan responses, including the dynamiting of a major landslide that formed a new lake and threatened major flooding should the natural dam fail.

Scientists studying the area say that in terms of geological time, volcanic activity in the region is relatively new. The major eruptions of the region took place 2.1 million, 1.3 million and 640,000 years ago. Since modern humans have only inhabited this planet for the last 200,000 years or so, all observations of the Yellowstone Caldera are after the eruptions took place. What we know is the result of observing the geological evidence left behind.

Except for four years of graduate school in Chicago and the last year and a half in Washington, I have lived all of my life within the region that scientists predict would be disrupted by a super eruption of the Yellowstone Caldera. Should such an eruption occur, human survival would be in question in all of those places. Predicting when a volcano will erupt, however, is not a precise science. What scientists do know is that there is a dramatic increase in seismic activity before an eruption occurs.

Much of what is known about volcanoes comes from those with a more recent history of eruption. The Mount St. Helens eruption in 1980 gave scientists an excellent opportunity to observe an active volcano. Mount St. Helens is small when compared to Yellowstone, however. Scientists estimate that the Island Park super eruption (2.1 million years ago) produced 2,500 times as much ash as the Mount St. Helens eruption. That amount of ash is pretty spectacular. Ash from the Mount St. Helens eruption filled the skies and left visible and collectable ash on the ground where we lived at the time, 1200 miles to the east of the mountain. Multiply that by 2,500 times and much of the world, especially the northern hemisphere is covered in ash.

Even though scientists can’t predict eruptions, it doesn’t seem likely that Yellowstone will erupt in the next few hundred years. The same, however, isn’t true of the five active volcanoes in my new home state. Washington is home to Mount St. Helens. Mount St. Helens continues to be monitored as a highest priority and potential threat. Lava continues to build up the dome in the crater, which has risen 1,500 feet. Another eruption is likely. Scientists just can’t say when it will occur.

Mount St. Helens is only one of five active volcanoes in the Cascades. The last reported eruption of Mount Rainier was in 1894, but never confirmed. The mountain still releases gases and steam from its opening and small earthquakes are a daily occurrence. The Osceola Mudflow, 5,600 years ago, filled valleys with sediment traveling at speeds up to 50 miles per hour. It is being monitored at highest priority and remains a potential threat.

Glacier Peak is one of the more dangerous volcanoes in our state because it has erupted frequently and has produced dangerous lava and mudflow. The last recorded eruption was about 300 years ago, but it, too remains highest priority for monitoring.

Mount Adams is the largest volcano by volume in the Pacific Northwest, but it has not had as many eruptions as the others. The latest eruption was about 1,000 years ago, though avalanches and mudflows have occurred as recently as 300 to 600 years ago.

The volcano that we can see as we drive between our house and our son’s house, Mount Baker, is also considered to be a highest priority threat volcano. It is one of the newest of Washington’s volcanoes. The last major eruption was about 6,600 years ago, but in 1975 surface activity and a collapse of the crater concerned scientists. There was no eruption at that time, but steam and gas can be seen coming out of the volcano from time to time. Mount Baker is best known for its record snowfalls. the mountain was topped by 95 feet of snow in the 1999 season. That is a world record for the most snowfall in a single season.

We enjoy our views of Mount Baker. It is a mountain of many moods as the clouds swirl around it. The mountain remains snow covered year round and reflects the light of sunset and sunrise in dramatic ways. It is amazing to us that we can see the ocean and the high mountains at the same time. I’ve taken pictures of the mountain from the ferry and from the islands of the Salish Sea. It is one of the most dramatic features of our home place.

An eruption of the mountain would have dramatic effects. Although it is likely that prevailing winds would carry the ash away from where we live, mud flows could clog rivers and streams and cause catastrophic flooding in our region. We do not know, however, when the next eruption will occur. It could be in hundreds or thousands of years. Knowing the power of the mountain, however, adds to the drama of looking at it. There is even more than meets the eye.

So far, however, living with volcanoes has not been difficult. We respect their power and live with the possibility of eruption. I’m glad they are monitoring the seismic activity on the mountains, but I’m not inclined to lose any sleep over the possibility of an eruption.

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