Kevin Myatt is The Roanoke Times' weather columnist.

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"The January 2008 snow cover extent was the largest extent over the 42-year historical record, surpassing the previous record set in 1985."

The National Climatic Data Center made that somewhat surprising statement in its January global analysis, released Feb. 14. The statement is referring to how much land was covered by snow on average in the Northern Hemisphere during the month.

It's surprising because, here in Southwest Virginia, we haven't seen any reason to believe a record snow cover was ongoing across the Northern Hemisphere. Locally, this winter just hasn't delivered the goods it has elsewhere.

But at a broader level, it's a surprising statement because we read and hear so much these days about records for warmth, not records for cold and snow. Yet, despite the observed and much publicized rise in Earth's surface air temperature, records for cold and snow have not stopped happening.

Global warming skeptics and activists alike can put their own spin on the record January snow cover in the Northern Hemisphere.

A skeptic could say the fact that there could be snow cover over a wider area in January than any during the past 42 years means that the fears of warming are greatly exaggerated.

An activist could say that a record winter snow extent indicates the presence of stronger storm systems being propelled by a warmer atmosphere. Yes, even massive snowstorms are propelled by atmospheric heat.

I'm not fond of either angle. I don't think this January's snow cover has much to do with global warming one way or the other, it's just something that resulted from the twists and turns of the atmospheric pattern that set up this particular winter. I don't think it makes much of a statement either way about man's effect on the atmosphere. I do think it says a whole lot about natural variability.

As the accompanying chart shows, snow cover extent is a highly variable statistic that fluctuates enormously.

Snow cover extent this winter is a little more than 3 million square kilometers (1.9 million square miles) above the long-term January average of 47 million square kilometers (29.2 million square miles), while it was about 2 million kilometers (1.2 million square miles) below average last year, according to the National Climatic Data Center.

Northern Hemisphere snow cover doesn't bear any correlation to what we've seen locally.

Six of the past nine years, though many were among the warmest on record globally, have featured above-average snow cover extent in January. Meanwhile, in Southwest Virginia, only one winter in that same time span has had above-average snowfall.

Furthermore, our most recent monster snowfall winter in 1996, when 56 inches fell for the season including a 2-footer in early January, was nothing special across the hemisphere. In fact, January snow cover extent was just a hair below normal.

Keep in mind that snow cover extent is not the same as snow depth. A broader expanse of 1 inch of snow would be recorded as greater snow cover extent than would a more narrow expanse of 3 feet. So snow cover extent doesn't necessarily address the issues of dwindling snowpack and glaciers in many mountain areas.

This particular record snow extent is also driven more by snow that fell throughout Europe and Asia, especially central Asia.

North America's snow cover extent alone was above normal in January. The same statistic for Eurasia was off the charts, a runaway record.

But the fact that more locations north of the equator had snow on the ground in January than at any time in the past 42 years does illustrate vividly that winter has not died, as some seem to believe.

A run of mostly mild, below-average snowfall years in Southwest Virginia hasn't killed winter. Neither has a series of strong to extreme El Nino and La Nina events in the Pacific. Neither, even, has global warming.

Cold and snow are still occurring around the world, sometimes quite severely, waiting on the right jet stream pattern to return real winter to our area in some future season.

On the Net:

January global analysis

tinyurl.com/2ztzme