I can survive in 9c but 100c will kill me.

If you actually live in those temp ranges, you’re fucked either way. Modern technology is what makes those ranges bearable.

That being said, I can bundle up pretty easy compared to mitigating heat.

Single digits for sure. I’ll be okay from -9 to +9, but I don’t really see a solution to a 999°F heatwave

Assuming modern technology didn’t suddenly disappear, I would pick the cold without a doubt. Give me a good sized greenhouse attached to my home for growing my garden and I would be happy as a lamb. I hate summer, and the heat that comes with it. While 9F is colder than I typically prefer for outdoor activities (I generally like it right around 40F) I can make clothing and gear adjustments to continue outdoor hobbies like hiking and backpacking. If it was perpetually colder here I would probably take up a snow sport too. (Currently it’s not snowy enough where I live for snow sports). Also if it’s that cold I would never have to deal with bugs again and I am 100% here for that.

As it currently is I’m basically stuck inside for 3 months of the year due to heat unless I want to drive 8 or more hours for a brief holiday respite. Summer is the worst. Give me arctic cold please.

Single digit temperatures. One can always wear more clothing to keep warm, but can only get so naked in triple digit heat before dying from exhaustion or dehydration.

Not even a choice.

If you choose over 100F you will see electronics failing more often, working harder, less efficient, working badly, etc because the heat is causing them to throttle in various ways. In the modern world it is far, far easier to heat up a space with a house full of electronics and humans than it is to keep it cool. The energy required to raise the temperature from say 5 degrees F to a more comfortable 40 degrees (35 degree change) pales in comparison to the energy required to keep yourself and your devices cool a mere 10-15 degrees less to around 90 degrees which is still uncomfortably hot and sweaty.

I’ll note that a constant 100 degrees is more than hot enough to cause various foods, medications, substances to break down and go bad. Check your medicine cabinet, most of your pills including over the counter are only rated for storage at up to 86 degrees. Your medicine will lose efficiency or go bad in some, perhaps many cases. Your food outside your fridge will spoil more quickly, mold and bacteria will grow more quickly and readily. Your fridge itself will work harder and die sooner.

The tap water will run hot or warm most of the time meaning a shower won’t necessarily cool you off much.

The colder temperatures are cheaper all costs considered, feel better, can be negated at a moment’s notice with socks, a jacket, and a blanket.

It’s easy to insulate a home against extreme cold and just retain heat you generate inside including by your body and devices. It requires a lot more effort to keep the inside cold when both the outside and things inside are generating heat and trying to warm it up.

This is a reason why climate change is a nightmare not just for human comfort but on so many levels. Our electronics are going to operate less efficiently in a warmer world and draw more power to do so.

This is a very different question outside of America and that one African country.

Single digit. It’s easier to warm up than cool down, and I can’t stand hot weather. I’m also fairly used to freezing temps.

I literally moved from a 38 degrees+ country to a negative temps country. So yeah. Negative temps. 100%.

U can wear warm clothes. There exist no “cold” clothes.

Ever since I had a heat exhaustion event in my late teens, I have been exceedingly sensitive to heat. Think actively sweating like I’m in a sauna - only in normal office temperatures. I have to shave my head for nearly half the year in order to not look like a drowned rat - and carry a “sweat towel” with me at all times to wipe the dripping sweat off a half dozen times an hour.

My home office is set to between 15℃ and 18℃ because that is the temperature where I feel the same amount of comfort as most other people do between 24℃ and 28℃. Throw a business suit into the mix, and that comfort range drops by 4-6℃.

There are times in the winter where I throw all the office windows open, let the -20℃ air roll in from outside, and actually enjoy wearing long pants and a sweater.

…I live in Canada. Near where it hit 50℃ during the heat dome a few years ago. Climate Change is going to be brutal for me.

Single digits. I love being bundled up. The less people look upon my decaying meat husk the better.

Also I like scarves a lot!! I want to wear them now, but it’s insanely hot to me!

I live in a spot where temps range between 19-39 degrees in the daytime, swinging from dry to humid every now and again.

I’ll take 1-9 C all day, every day. Despite living here my entire life, temps above 25 are uncomfortable for me. I’ve discovered that temps between 5 and 14 degrees for me are ideal.

Arid, or humid?

It makes all the difference at higher temperatures. 100°F in Nevada or New Mexico is NOT the same thing as 100°F in Florida or Tennessee.

First choice: 292 K

Second choice: 9 C

If we’re talking only outdoor temperature, third choice is 100 F, because air conditioning exists, and my peppers would thrive.

If it’s ambient indoor temperature too, then I pick 9 F, which is unpleasant, but survivable. At 100 F indoors, you will be constantly sweating for the rest of your life.

Day to day, I’d take a dry 100 degrees. My problem is a like to do cardio exercise outside, like run and bike. 100 degrees makes that significantly more difficult and dangerous. We’ve had upper 90s and high humidity the last couple of weeks and it’s been tough to do anything more than about 20 minutes at a time.

On the other hand, I love to snowboard, which can’t happen in triple digits. Snow and ice depending, biking and running are doable at single digit temps. I hate walking outside and feeling pain from the cold temps.

I’d probably take the triple digits and travel for cold vacations.