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Correction. Minnesota gets temperatures from -20 to 100. Tomorrow has a high of 97. Definitely not an odd place for AC.

I was just about to call "BS" on that wimpy zero. Zero is brisk compared to some of the lows in and around Minnesota, and pushing near 100 isn't uncommon. Not every year, but many, certainly.

0 deg F is a t-shirt jog here in Minnesota during the winter. Cold is -20 to -40 range. And within the last few weeks, we've had several days 90+ and 100+ deg F. There's a reason lots of the old people migrate with the ducks down south for winter.

Pretty much... I like to tell people that it's not really cold here until your snot starts freezing the instant you go outside. That tends to happen at 10-15 below zero (Fahrenheit).

97 is not that hot. I've spent months in those temperatures without AC just drinking water.

Almost everywhere, AC is truly a luxury.

I just Googled 97 degrees, expecting some large temperature, and it's only 36 degrees! For comparison, it's 40 C here today.

Stay out of the sun, sweat a little, you'll be fine. Arabs have it much worse.

Humidity's usually a bigger problem that the actual temperature. 100 degrees in drier parts of the southern US doesn't feel anywhere near as bad as 85 degrees in rainy towns up north.

Ah, yes, that would complicate matters somewhat... High humidity is unbearable in the heat.

It is approximately human body temperature. By design it should be slightly less, Farady intended 100 degrees to be the human body temperature but obviously suffered a light fever the day he took the measurment, so these days the human body has 96 degrees. 0 degrees Fahrenheit is defined to be the coldest it could conceivably ever be on the outside in winter, according to Faradays intuition when he decided that this is the coldest day ever. I don't know if he caught the fever during that measurement.

Fahrenheit was invented by a guy named Fahrenheit, not Faraday.

> Faraday

Fahrenheit. (It doesn't seem to be true that he intended 100 degrees to be human body temperature. It's possible that he specifically wanted the difference between body temperature and freezing point to be (a power of 2) degrees.)

Farenheit's "body temperature" was the axillary (armpit) temperature, and he set it to 96 degrees (on average) when creating his scale. And yes, your supposition about the divisibility of key numbers is right.

D'oh, stupid thinko, sorry for the confusion. (And Faraday and Fahrenheit don't even share the same soundex...).

The point about humidity has already been made. I was astonished at how comfortable 115 degrees was in Phoenix. I went on a hike, no problem... Except that I carried a huge water bottle and the bottle ran out in an hour, so there's that.

In humid places, however, sweating is almost useless and you can suffer in mere 90F heat.

The other important point is that somehow folks in Singapore manage to survive, but in Singapore there's never any winter. I once heard a physiologist remark that humans can adjust to a wide range of temperatures, but it takes a few days for the body to reprogram itself for freezing ambient temperatures after spending months in roasting ambient temperatures. That's why the first few days of cold weather in the fall and winter feel really cold and everyone dons parkas, but when spring rolls around the exact same weather feels really warm and everyone puts on their shorts.

So maybe if I set out to live without A/C I'd get more used to it after a while. But the first few days are a killer, and at some point one just gets sick of being listless and warm and starts subconsciously looking for excuses to visit nice air-conditioned buildings.

it takes a few days for the body to reprogram itself for freezing ambient temperatures after spending months in roasting ambient temperatures

I noticed this empirically with myself whenever I traveled from California to Sweden in the winter. Coming to Sweden, I'd be cold all the time for the first couple of days, and then back in CA, I'd have hot flashes for a few days there. Nice to know that I wasn't imagining things. :)

I always assumed the heat-capacity of my bones took much longer to change temperature than the muscles and flesh of my body, but once it does, it lasts longer too.

The problem for most of us in the US is that we can't control how much they refrigerate moste public places. We keep our home ~80F(it makes going outside in south Texas much more comfortable), but that makes my office very uncomfortable at 74F.

You are making an assumption that the Middle East is nothing but a dry desert; the forecast for tomorrow afternoon in Jeddah, Saudi Arabia is 101 degrees with a 29% humidity.

The difference that humidity makes cannot be overstated. When it's hot but not humid, sitting in the shade makes a big difference. When it's hot and humid, sitting in the shade just means its not as bright.

It's absolutely not a luxury in the south. You can stand up and walk around with the humidity, but you'll need a steady stream of fresh clothes if you sit to do anything without AC.

This is why I love living in Michigan. Like Minnesota, we get temps from well below freezing up to 100F. Real winters. Real summers. Crisp frost and gorgeous colors in the fall. Spring is worth celebrating.

I won't trade it for Phoenix until I turn 65. But yes, it does make heating, cooling, clothes shopping, and a host of other things a little more difficult than the southern states.

The view of HVAC varies wildly depending on where you live. It's similar to big trucks, guns, and heavy machinery. In suburbia, these things are pure decadence and waste. In the outback they are tools of the trade, no different from the briefcase a businessman carries.

Can you rephrase your last sentence? I've reread it a few times, and I just can't make heads or tails of it.

Thanks!

Powered heating is a fundamental human need in Minnesota. You cannot survive without it. Even in antiquity I can't imagine people surviving without fire.

Passive cooling, by contrast, is pretty much adequate (though that's not to say the heat can't kill you if you're out in the sun.) But in any case, when you look at the amount of energy expended on heating, the modest amount expended on cooling is a natural expenditure. I think in general that's why a lot of colder countries like Norway are more rich and prosperous than their warmer counterparts. When it costs $30,000/year just to survive, luxuries start to become a lot less costly as a percentage of income.

Can passive cooling remove moisture from the air? That's essential for anything that wants to replace powered cooling in the southern US.