Arctic ice may expand

I’ve recently received e-mails from some folks who are worried about the melting arctic sea ice, which shrank to its second lowest level on record Sept. 12, at some 1.74 million square miles.

The lowest level of sea ice measured in the arctic regions since at least 1979, when such record-keeping began, was last summer in 2007. In early September 2007, the sea ice covered 1.59 million square miles.

This arctic sea ice, which floats on top of the ocean, every year expands in the winter months and retreats each summer season. The trend during the past decades of warming has been toward thinner winter ice packs. But, with 2008 likely to go into the record books as the coolest year since the early 1990s worldwide, it’s possible that we’ve seen the lowest levels of sea ice in the arctic regions for at least a generation, maybe longer.

If this winter season in the arctic is as harsh as many experts predict, it’s likely that next summer’s lowest sea ice level will be somewhere near 1.87 million square miles, 280,000 square miles more than in 2007, and 130,000 square miles more than in 2008. By 2010, we could easily see a lowest summer arctic sea level exceed 2.05 million square miles.

The oceans take much longer to cool down during a cooler climate phase like this than the surrounding land masses. The land temperatures peaked a decade ago in 1998 on a global scale. The oceans are taking at least a decade, possibly longer, for such a trend to develop worldwide.

Despite the Earth’s recent cooling, temperatures in the arctic regions have been generally higher than normal. Scientists are uncertain why this region has been warmer than average in recent years.

One possible explanation for the warming is the active underwater volcanoes that were discovered in this region earlier this year. Recent massive volcanoes have risen from the ocean floor deep under the arctic ice cap. Large eruptions, perhaps as big as the one that buried Pompeii, took place in 1999 along the Gakkel Ridge, an underwater mountain chain from the northern tip of Greenland to Siberia, pouring hot lava into the Arctic Ocean that may have led to the melting of some of the sea ice.

As far as our local weather is concerned, we should have a pattern of wide fluctuations of warm and dry to cool and showery in October. Our winter should start off a bit cooler and snowier. I’ll have a more detailed snowfall forecast next week.