Wednesday, June 21, 2017

Hot Alban Hefin

Today is the summer solstice for most of the world. In California the solstice actually occurred just before midnight, when, somewhere in the Middle East, the sun passed directly overhead. It was hot for the solstice in much of California as it had been hot all day, and the residual sun’s heat had not yet dissipated into the California desert night as the direct rays of the sun heated the deserts of Iran.

Just a few degrees north of the Tropic of Cancer in the Middle East is a weather station named Mitribah. Mitribah is in a desolate part of a desolate landscape, and it gets hot there in the summer. On July 21st 2016 the Mitrabah weather station may have recorded the highest temperature on earth ever reliably recorded. That temperature was a sweltering 54oC (129.2oF). Weather stations in Death Valley California may have recorded the same temperature, and have unreliably recorded a much higher temperature (56.7oC on 10 July 1913 at Furnace Creek Ranch), but the hot parts of Death Valley are quite a few meters lower than sea-level, and Mitrabah has an elevation of 119 meters.

It is hot in Mitribah today; temperatures were in the range of 40oC. It is even hotter in Death Valley; temperatures may hit 53oC there.

Today is the official solstice day here in Utah, even though it occurred just a little after midnight local time. It will be hot here; hot like Mitribah was today, not as hot as Death Valley. If I am lucky I will get out for a short lunchtime bike ride. Riding a bicycle in the super heat is an exercise in tempering one’s effort to minimize heat buildup while creating enough personal wind to generate evaporative cooling from high tech fabric and sweat. It only feels really hot when I stop.

If I was in Death Valley and catastrophically stopped while cycling I could suffer severe burns when I came into contact with the tarmac. In addition to “road burn” caused by abrasive removal of dermis I could actually suffer severe thermal burning from the hot asphalt. Black road surfaces can reach temperatures in excess of 70oC. Air temperatures around 70oC are sometimes used in saunas, but contact with a hot half melted tar surface transmits that heat to the skin very efficiently. When raised to temperatures in excess of 44oC most of the proteins in human cells begin to break down; this is colloquially known as “literally cooking”.

Most consumer electronic devices overheat long before they are exposed to ambient temperatures of 70oC. So even if you were lucky enough to crash in a part of the American desert where there was cell phone service your cell phone would have given up its own ghost after a few seconds of lying on the pavement next to your sizzling bacon-scented body.

Anyone who has been outside with other people when the air temperature in the shade exceeds 45oC knows that people start acting stupid. The brain generates a lot of heat and when the body cannot dissipate that heat properly people begin to misplace aspects of their cognition. Hallucinations are possible, but the whole experience is so unpleasant that I have never heard of anyone going in search of heatstroke for a recreational high.

It makes sense to blame the high temperatures on global warming. In fact it sounds like the two are causally linked by definition. However, these are excursion temperatures and the link is not direct enough to lead naturally to answers like “how hot can it get?” or “How many hot days can we expect?”. The expected answers of “Hotter” and “More” are glued together with a bunch of “I don’t really know”s that just don’t feel satisfying to me.

If the record high temperatures increase just shy of 10oC the environment will not just be irritating and dangerous; it will become unable to support human life. We will not pop like popcorn when we go outside, but we will need to hide from the great nuclear furnace in the sky by huddling in our cool caves in order to survive the day.

So…. I would love to wish you a happy summer solstice (Some people call it Litha or Alban Hefin), and hope you get outside for a bit, but not too long.

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