In the wake of Winter Storm Hercules, parts of the East Coast will see record-low temperatures. In some places, the temperature is expected to be 20-30 degrees lower than normal. That's kind of a lot lower. So what's up with all this frigid air if the planet's warming due to carbon emissions?

“The bottom line is, I don’t find it extraordinary,” John M. Wallace, an atmospheric sciences professor at the University of Washington, told NASA back in 2009. “With or without (man-made) warming, you’re going to have big variations in these patterns.”

PHOTOS: Winter Storm Hercules

So even as we experience some of the hottest years on record, in terms of overall global average temperature -- trends that are most accurately recorded over 5-11 years -- it can be hard to believe we're experiencing climate change when your back hurts from shoveling snow.

Back to the climate experts at NASA:

"Surface temperatures from year to year will fluctuate depending on the naturally variable forces at work around the globe. In the early 1990s, the mass of sulfates blasted into the atmosphere by the eruption of the Mt. Pinatubo volcano reflected sunlight and counteracted much of the man-made warming effect for several years. In 1998 El Nino combined with the man-made effect to give us one of the warmest years ever."

NEWS: Snowstorm Slams U.S. Northeast

Global warming doesn't mean that every year the climate will be hotter than the previous one. And it doesn't mean we'll see the end of snow days, to the relief of school children and teachers everywhere.

But it does mean, according to NASA scientists, there's no global cooling trend. Decade to decade the planet is warming -- and will continue unless we can control greenhouse gas emissions.