Kevin Myatt is The Roanoke Times' weather columnist.

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Whether or not there ever is a "Day After Tomorrow," there once was a real "Year Without a Summer."

1816 was the infamous "Year Without A Summer." Frost occurred as late as June in portions of Virginia, and snow fell throughout the Northeast during that month. A killing frost occurred the second week of July in New England, and Arctic cold fronts passed through in succession during August.

Though the fronts brought various forms of precipitation with them, the cold weather was accompanied by extremely dry conditions. That made 1816 also a year without a growing season, and in the subsistence farming of early America, that meant that many settlers had little or nothing to eat. Europe experienced a similar chilly drought.

Studies of temperature records in the Northeast have shown that the summer averaged 5 to 7 degrees below normal in many areas. A summer that cold has no parallel in the last century. (Locally, the closest thing I could find is Blacksburg's record low of 30 on June 11,1972. Roanoke's latest freeze since 1948 has been on May 11, 1966, though May 22, 2003, missed by only one degree).

But 1816 as a whole was only one of several chilly years within that decade. Many years in the 1810s were abnormally cold, according to what weather records we have from the time.

Nearly 200 years later, scientists focus on two possible culprits in the frigid summer of 1816.

Most emphasis is placed on the 1815 Tambora volcano that erupted violently in Indonesia, wiping out approximately 10,000 local inhabitants and possibly as many as 92,000 through indirect effects.

If Tambora were a stick of dynamite, the 1980 Mount St. Helens eruption that turned 230 square miles of Washington state into a moonscape would only be a firecracker. The U.S. Geologic Survey estimates that Tambora shot somewhere between 30 and 80 times more volcanic ash into that atmosphere than did St. Helens. Some estimates range up to 150 times as much.

The ash from Tambora is believed to have spread around the world and blocked out sunlight, cooling the atmosphere significantly.

Volcanic effects on climate have been observed. Mount Pinatubo's eruption in the Philippines in 1991 (it was about 10 times larger than St. Helens) led to two years of decreased global temperatures that briefly seemed to offset any previously observed global warming effect. When the ash finally filtered out of the atmosphere, worldwide average temperatures began climbing again, and several of the warmest years on record have occured since 1993.

A second factor implicated in the cold year is an unusual period of lower solar activity that lasted for decades in the late 1700s and early 1800s. Even in the maximum periods of the 11-year sunspot cycles known to exist, far fewer sunspots than normal were observed. The result was less magnetic activity and, therefore, a perceptibly dimmer sun.

Perhaps it was a disharmonic convergence of both of these factors that canceled summer unceremoniously in 1816.

One theme I infer from 1816 is this: No matter what kind of junk humankind is putting into the atmosphere today -- and there is solid evidence that we are having at least some impact on climate -- we are still puny and helpless stick figures compared to the power of nature. Volcanic eruptions and solar cycles still trump the exhaust pipes of SUVs. The weather is far more in control of us than we are of it.

Whether you want to make that a scientific, philosophical, political or theological statement is your interpretation.