Too early to determine fallout from volcanoes

THURSDAY, NOV. 11, 2010

Last week, I talked about the increased volcanic eruptions in Indonesia and Russia. Mount Merapi, located on the central Java Island in Indonesia, began erupting on Oct. 26 and continues having periods of explosions.

According to volcano scientists, the eruption on Nov. 5 at Mount Merapi was the largest since it previously exploded in 1872. Last Friday, the volcano threw ash and hot gas 55,000 feet into the air. It’s unknown whether this eruption was big enough to have some kind of global climatic effect. Scientists say that a lot depends on how much sulfur dioxide was released into the atmosphere.

The last big volcanic eruption that may be compared to one at Mount Merapi was Mount Pinatubo’s eruption in June of 1991. At that time, 20 million tons of sulfur dioxide was sent 17 miles into the stratosphere resulting in a 1 to 2 degree Fahrenheit drop of the Earth’s temperature for several years.

Since Saturday, the Bulusan Volcano in Bicol, which is located in the Philippines, has been releasing volcanic ash resulting in advisories for pilots not to fly close to this region.

Back in the Inland Northwest, the turning back of our clocks last Sunday has reminded us that winter is not far away. Many of us did enjoy some nice weather in October and early November. The average temperature last month at the Spokane International Airport was 49.7 degrees, which was 2.5 degrees above normal. Precipitation was also above average levels as 1.54 inches was measured in October. The normal rainfall for October is 1.06 inches.

As of early Tuesday, the average reading at the airport for November was 47.1 degrees, which is a whopping 7.9 degrees above normal. Precipitation continues to be above average as we’ve seen a total of 0.83 inches since Nov. 1.

Looking into the meteorological crystal ball, it still looks favorable for moderate to heavy amounts of snow to fall during the full moon lunar cycle just ahead of the Thanksgiving holiday weekend, especially above 3,500 feet in elevation. This would be good news for many of the area’s ski resorts.

Based on the moderate cooler-than-normal, sea-surface temperature event, La Nina, I still see at least 20 percent more snowfall than normal in the 60-day period from late November through late January before the snows taper off in February and March. The chances of a brilliant white Christmas are a little better than 50 percent in Spokane, but near 70 percent in areas to the north and east of Spokane.

Contact meteorologist Randy Mann at randy@longrange weather.com.

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