Wed March 20, 2013
Though It Doesn't Feel Like It In Parts Of The Country, It's Really Spring!
Originally published on Wed March 20, 2013 8:58 am
Don't tell Chicago, Buffalo or Minneapolis — which will see high temperatures just in the 20s, today — but at 7:02 a.m. ET., the Earth's axis was neither tilted from nor toward the sun, marking the beginning of spring in the northern hemisphere.
So: Happy spring equinox!
The National Weather Service provides this explanation for what's happening with the Earth's orbit:
"On the equinox, night and day are nearly exactly the same length – 12 hours – all over the world. This is the reason it's called an "equinox", derived from Latin, meaning "equal night". However, even if this is widely accepted, it isn't entirely true. In reality equinoxes don't have exactly 12 hours of daylight.
"The March equinox occurs the moment the sun crosses the celestial equator – the imaginary line in the sky above the Earth's equator – from south to north. This happens either on March 19, 20 or 21 every year. On any other day of the year, the Earth's axis tilts a little away from or towards the Sun. But on the two equinoxes, the Earth's axis tilts neither away from nor towards the Sun."
We know that's not much comfort for those of you stuck with winter-like temperatures. But The Washington Post's Capital Weather Gang reminds us that the equinox also begins another process.
From now on, "the sun's declination – or height with respect to the horizon – is increasing at its fastest pace of the year."
That means more sunlight every day, which means that no matter how hard winter tries to overstay its welcome, "spring can't be far behind."
(Beijing, by the way experienced a rare spring snowstorm.)