Coming earlier....

Spring is coming earlier than it has in over 100 years

By Scottie Andrew and Brandon Miller

For once, the groundhog got it right.

Punxutawney Phil is no doubt enjoying a long winter's nap after he correctly predicted the Northern Hemisphere would see an early spring.

Date-wise, he was spot on: The spring equinox will occur on March 19 this year. And according to the Farmer's Almanac, it's the earliest equinox the Northern Hemisphere has seen in 124 years.

Not that you'd notice. The equinox, which marks the first day of spring, is happening minutes to hours earlier than in years previous (it typically falls on March 20), so the change is basically undetectable.

But Phil might've been onto something when he made his prediction: The onset of warmer spring weather is much more obvious a change, and it's happening earlier every year.

Global warming is the culprit.

Hotter global temperatures cause an earlier spring

The spring equinox marks a turning point in the year, when days finally grow longer and the biting cold starts to subside. It's happening a bit earlier than usual this year because of positional changes in the earth's elliptical orbit and the uneven length of seasons, according to the almanac.

But the accompanying spring weather is beginning earlier in much of the US than it did in most of the last century, according to the Fourth National Climate Assessment, a report released by the US Global Change Research Program.

Pockets of the US are getting warmer and warmer weeks earlier than usual. And when the world's weather is out of whack, organisms who rely on changing seasons to calibrate their internal clocks can be thrown out of tune, too.

Sarah Peach, a senior editor at Yale Climate Connections, explains: Ice is melting, flowers are blooming and birds are migrating earlier in the year than they typically would. And when the air warms up but the length of days stays the same, species that rely on each other become "mismatched," she said.

So while an early spring teases the welcome return of warm weather, the natural world must speed up, too. And the quicker spring comes, the more difficult it is for species to catch up.