Perfect temperature: This is when it matters

On January 21, as hundreds of thousands convened in the nation’s capital for the Women’s March on Washington, scores of smaller”sister marches” were held across the country – including on the Walkway Over The Hudson between Poughkeepsie and Highland and in Woodstock (shown above). The marchers were lucky to see 50 degrees in late January. These are statistically the year’s coldest few weeks, with a normal high around freezing and normal nightly low around 13 degrees. (photo by Dion Ogust)

I’m writing this on Saturday, January 21: one of those rare perfect winter days. My digital outdoor thermometers disagree with each other; the one on my home’s south side says 57 degrees in the shade, while the northern one insists it’s 53. Either way, it feels wonderful out there.

My Significant Other Marcy thinks that 50 degrees is a threshold, and I agree. Air colder than that feels like winter. But at around 50 the world starts feeling pleasant, and forest smells return. That’s also the threshold for insect activity. Their cold-bloodedness prohibits them from moving or flying when it’s chillier than that.

We are lucky to see 50 degrees in late January. These are statistically the year’s coldest few weeks, with a normal high around freezing and normal nightly low around 13 degrees.

Out in Boulder, Colorado, two of the nation’s top climate scientists told me that our region should see its greatest anthropogenic changes during winter nights. Extra atmospheric CO₂ should make our lows less low. This seems to be happening.

I’ve been carefully measuring Ulster County temperature since 1972, and it does seem as if we are getting fewer super-cold snaps each winter. In West Saugerties and in Willow, I measured negative-26 degrees on two nights long ago. But in the past 20 years, our greatest annual winter cold spells “only” plunged the temperature down to around minus-12 degrees. And this winter we’ve never once gone below zero.

Looking through the telescopes of Overlook Observatory, we observe nothing but extreme temperatures. Our coldest nights are 100 degrees warmer than a typical Martian day. The Moon’s surface broils at 230 degrees, and then drops 400 degrees when the Sun goes down. But paradoxically, the coolest part of the Sun is the brightest part: the glowing gaseous surface or photosphere. That simmers at around 10,000 degrees Fahrenheit – around where liquid tungsten starts to boil. As you go farther away from the Sun, its atmosphere or corona sizzles at an inconceivable four million degrees.

Conversely, every shadow in our solar system has temperatures as low as five degrees above absolute zero – except here on Earth: the only island of moderation in the known universe.