Unalaska, AK – On June 25, 2009 , Mount Cleveland had a small eruption and the Alaska Volcano Observatory set the aviation color code to orange. By June 28, it was downgraded to yellow and now it is currently unassigned. The coding of Cleveland varies greatly because the volcano, though it frequently erupts, has no monitoring equipment on it and is only monitored via satellite. The uninhabited island is 40 miles from the nearest town, Nikolski.

Professor Kirsten Nicolaysen of Whitman College recently gave a talk on the active and enigmatic volcano at the Museum of the Aleutians. She and her colleagues began studying the volcano in 2002. She said the island's name, Chuginadak, means "The Quite One" but Cleveland has erupted more than 30 times since 1774.

Nicolaysen said that despite this, "it had never been mapped, it had never been sampled by a geologist. We didn't really know what was coming out and how explosive it might be in the future. And we had no idea how old the previous lavas were or how often the volcano erupted. And these were all important things to determine in order to have some ability to predict what the future behavior of the volcano might be."

This is especially important because Cleveland is located in a particularly explosive part of the Aleutian arc where the North American and Pacific plates have significant direct contact. And the volcano has been very active lately - it erupted this summer, last winter, and last summer.

When exploring the island, Nicolaysen wanted to know how dangerous it was. She and her team camped twice on the island.

When you establish your base camp, "you hope that the volcano doesn't decide to bury you. You hope that it really is the 'quite one' while you're there," she said.

While she was there she learned about the geochemistry of the volcano. Areas showed evidence of large amounts of acid created by sulfur during some eruptions, making some of the debris a bit hazardous.

"I learned a good lesson, which was I was walking around the 2001 deposits and I saw this kind of bright yellowish-orange rock. It looked really interesting. And I picked it up and looked at it for probably less than five seconds and I felt it burning my fingers. Not because it was hot but because it still had acid adhering to it."

Other areas showed that the lava has less silica in it, which makes it less explosive. "Cleveland is going to erupt," she said, "but by and large what we see is that it's not going to be a super explosive eruption probably because the lava chemistry isn't just right."

But that doesn't mean that Cleveland is altogether safe. Nicolaysen and her partners found evidence of lahars on the volcano. These mixtures of water and volcanic material can be very hazardous.

"Actually, the only fatality that we know of in entire Aleutian arc" caused by a volcano "came in the 1940s. When a service man, they heard the volcano doing sort of interesting things and one guy kind of took off on his own and when they went looking for him later they saw foot prints and they kind of ended where the lahars was. So these things also move very quickly. You don't want to go stand in one of these ravines. And actually I believe that since we were there some the more recent eruptions have covered our camp."

They also found remnants of pyroclastic flows, which are very fast moving currents of gas and rocks. Nicolaysen says that the end lesson is, "after this talk, don't decide to go camping on Cleveland."

So it's not the best place to vacation, but overall the volcano does not pose major dangers to the region. Nicolaysen and her colleagues did not find evidence of major avalanches that caused tsunamis nor is the island about to explode. Surrounding areas are sometimes covered in ash and ash clouds from Cleveland have even reached Canada, but it's not likely to be the next Pompeii.