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Have you ever wondered why a stone or cement floor is colder to your bare feet than a wood or carpeted floor? If both floors are the same temperature, the former will feel colder because those materials conduct heat more efficiently. In this case, the heat being conducted is coming out of your foot. If you put a thermometer on the stone and the carpet, the readings would be the same.

One floor is not actually colder, but your foot loses heat faster to stone than to carpet, making it feel colder. For once, it really is all about you.

As the rest of the country swelters in waves of heat, we can entertain ourselves with such an academic quandary, replay the Copernican controversy that ended the Dark Ages, and ruminate on how grade inflation came to meteorology. While we’re at it, let’s devise our own weather statistic, suited to our unique climate and culture.

You may have noticed a new term popping up with greater regularity in news reports this summer: the “Heat Index.” This statistical interpolation used to be called the “temperature humidity index,” but its simpler moniker has raised its stature to match its wintery cousin: the wind chill factor.

For the past two generations, weatherheads have been warning winter watchers about the wind chill factor, which combines temperature with wind speeds to express how quickly a human body will lose its warmth.

I grew up in Chicago and I can tell you the wind chill factor was a big part of my young life. We’d bandy about those stats at the bus stop, feeling like characters out of a Jack London story. On a cold and blustery day, getting the mail was an act of heroism well within the reach of a shy, skinny kid.

Now the Heat Index does the same for summertime, adding humidity to heat to describe how slowly a human body will be able to cool itself. Now we can be told all year round how cold or warm it feels.

It’s good to be reminded how quickly our bodies will freeze or overheat. But if you’re watching your crops or starting your car, the actual temperature matters more than its dramatic and humanized cousins.

We naturally want to believe the world revolves around us. The Powers That Be were slow to embrace the Copernican contention that the earth revolves around the sun instead of the other way around.

Darwin later nudged us off our pedestal of species singularity, offering a continuum of creation that follows a single set of rules. Humans have been trying to find their place in the world ever since. Maybe the Heat Index helps.

Does it really matter how the world is? Can’t we just talk about how it feels to us?

For once, Eugeneans can here claim to be an oppressed minority. Our weather rarely gets hot or cold enough to evoke sympathy from any other place. Even with inflated “how it feels” numbers, we almost never get to triple digits in the summer or negative numbers in winter.

“Hot enough for you?” just isn’t a conversation starter. Summer humidity is like diversity to us — something we read about and believe in, but seldom experience.

Eugene is often described as a small utopia, surrounded by reality. We don’t live in the real world, but we can see it from here.

So we need our own system for measuring hot and cold that works just for us. We expect every day to be 66 degrees — if for no other reason, for maximizing free expression. Some will choose shorts; others will wear three layers and carry a jacket, just in case.

Let’s call that the Eugene Comfort Optimum Temperature, also known as the ECO-Temp. Mark 66°F as zero (0°E) in our world and measure from there. Admittedly, the ECO-Temp lacks drama, but it offers the elegance of symmetry. When the ECO-Temp reaches 34 below zero, water freezes. Thirty-four above zero equates to triple digits in the Fahrenheit world.

Isn’t this really what we want to know every day? How far from perfect is today’s weather? (Answer: Not very.)

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Don Kahle (fridays@dksez.com) writes a column each Friday for The Register-Guard and blogs.

Tags:   Don Kahle · Heat index · Humidity · Meteorology · The Register-Guard · Thermodynamics · Weather2 Comments