Part I: A major Icelandic volcanic eruption could have a global impact

We seem to be heading into a period of very intense volcanic activity that could result in additional global cooling in the coming months and years.

Just this past Sunday, Mount Gamalama in eastern Indonesia erupted, forcing the closure of the busy Ternate Airport.

Nearby villages were covered with thick ash. Fortunately, there were few injuries and no reported deaths.

Indonesia has about 500 volcanoes. At least 65 active volcanoes are deemed 'dangerous' and could erupt at any time.

The perilous El Hierro Volcano in the Canary Islands off the northwest coast of Africa has been under a 'red alert' now for the past several weeks. A massive eruption may be "imminent," according to scientific observers.

But, there are even bigger worries about a possible catastrophic eruption soon in Iceland that could have a global impact.

Hundreds of meters under one of Iceland's largest glaciers, there are signs of a looming volcanic eruption that could become one of the country's most powerful in almost a century.

The mighty Katla Volcano, with its 10 kilometer (6.2-mile) crater, has the potential to cause disastrous flooding as it quickly melts the frozen surface of its caldera sending billions of gallons of water surging through Iceland's east coast and into the Atlantic Ocean.

"There has been a great deal of seismic activity lately in Iceland," according to Ford Cochran, the National Geographic Magazine's expert on the country.

Cochran adds, "in the month of October alone, there were more than 500 tremors around the caldera of Katla."

The increasing number of earthquakes in the region certainly suggest that a major eruption of Katla could occur at any time.

The last major eruption occurred in 1918 and caused such a large glacier meltdown that icebergs were swept into the ocean by resulting floods.

The volume of water produced in a 1755 eruption equaled that of the world's largest rivers combined.

Thanks to the great works of historic literature known as the Sagas, Iceland's volcanic eruptions have been well documented for the last 1,000 years.

But, comprehensive scientific measurements were not available in 1918, so volcanologists have no record of the type of seismic activity that led to that eruption.

All they know is that Katla usually erupts every 40 to 80 years, which suggests the next significant event is long overdue.

Katla is part of a volcanic zone that includes the Laki craters. In 1783, volcanoes in the area erupted continuously for eight months, generating so much ash, hydrogen flouride and sulphur dioxide that it killed one in five Icelanders and half of the country's livestock.

"And it actually changed the Earth's climate," says Mr. Cochran.

PART II: NEXT WEEK: Could a major eruption in Iceland bring on a disastrous 'nuclear winter'?

NORTH IDAHO WEATHER REVIEW AND LONG-RANGE OUTLOOKS

The first week of December was the driest on record for the Pacific Northwest, including the cities of Seattle, Portland, Spokane and Coeur d'Alene, where we also had a record number of hours of sunshine (31) during the seven-day span ending on Wednesday, this despite the 'air stagnation' advisories.

Spokane, as of early Thursday, Dec. 8, was actually below normal in total precipitation for the year at just 14.46 inches of rain and melted snow since Jan. 1. This compared to the normal precipitation to date of 14.86 inches in Spokane and last year's 14.80 inches in 2010.

We've been much wetter than normal in 2011 in Coeur d'Alene, thanks to an extremely soggy spring season and nearly 4 inches of liquid moisture in November that included an above normal snowfall total of 10.9 inches and the earliest opening of Schweitzer Mountain Resort since 1984.

Speaking of snow, I still see some of the white stuff returning to the Inland Empire during the Dec. 10-17 "full moon" cycle and again a week later that should give us a great shot - better than 80 percent - of another brilliant White Christmas in Camelot.

Randy Mann still tells us that the cool, wet 'La Nina' event in the waters of the Pacific Ocean continues to strengthen and should peak in early 2012.

I believe that late December and early to mid January will be quite cold and snowy in our part of the country, if the current huge high pressure ridge does indeed 'break down' as expected during the next 10 days or so.

We could receive anywhere from a low of 60 inches to a high of 100 inches of snow this winter of 2011-12 in Coeur d'Alene. But, once again, only time will tell. Stay tuned.

LATE NOTE

The first third of December, which ended at noon on Sunday, was the driest such period in Coeur d'Alene and elsewhere in the Pacific Northwest since at least 1895. We're still hopeful for snow this week!

Cliff Harris is a climatologist who writes a weekly column for The Press. His opinions are his own. Email sfharris@roadrunner.com