Comment by somenameforme | Hacker News Reader

Comment by somenameforme | Hacker News Reader

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Here [1] is a wet bulb calculator. The first time I started playing with it, I actually assumed it was must have been somehow wrong. But as I get the same results from numerous other calculators, I can only assume it's right. The problem you run into pretty quickly is that the supposedly 6 hours of inescapable lethality at 35C occurs regularly around the world, and often significantly higher.

And people, in general, are not just dying in mass because of it, including those who work outside most of all day. For instance in Houston yesterday it was 41C/81%, which is a wet bulb of 38. Places with rainy seasons during hot parts of the year are also nailing it pretty regularly. Its things like this that I think causes distrust of reporting. There may be some nuance or explanation I'm missing, but it's not at all apparent. It's also not at all apparent to me why more people aren't asking this question.

[1] - https://www.omnicalculator.com/physics/wet-bulb

I don't know where on earth you got those numbers for Houston from... that would be a world record by an amazing margin. Very few places to date have recorded wet bulb temps above 35 degrees.

I can only assume you are putting incorrect readings into the calculators.

Are you making sure to put the temperature at the time of the humidity reading, since they reach their maximums at very different times of the day. If you just put max temp and humidity readings for a day in you are going to be wildly wrong.

This could well be it. It never really occurred to me how radically the humidity changes throughout the day. I suspect this is because as the humidity rises the temperature is in a low and vice versa. So it feels like a relative equilibrium, but it's not. It'll be interesting to check out the by-the-hour data the next time a particularly mean hot+wet window emerges.

Wet bulb temps are lethal if you don't have external cooling. Houston has AC and cold water though.

Not everybody. Lots of people work outdoors for 6+ hour shifts, have transport jobs without AC, and so on. You could also consider primitive cultures. I know the Amazon can get upwards of 40C. I am not as familiar with the humidity on these days, beyond the fact that it's hella humid. And 40C + 70% = 35 wet bulb.

If the 35 wet bulb hypothesis was valid, then literally one solitary day of this, regardless of how infrequent, would have killed everybody in the Amazon. There are also many other areas along the equator with high temperature, high humidity, and lots of people without access to AC. Something just doesn't seem right.

This would suggest Brazil's record wet bulb temps are in the low 30's

https://news.climate.columbia.edu/wp-content/themes/sotp-fou...

Perhaps you should contact the researchers who are cited at https://en.wikipedia.org/wiki/Wet-bulb_temperature#Highest_r... because you appear to have independently discovered new global records.

Lots of dumb things have happened because people just assume somebody else would have checked [x], where [x] is something painfully trivial. My favorite example is NASA destroying a Martian orbiter [1]. Thousands of people involved in a NASA project carried out over 5 years, at the cost of about half a billion dollars. The mission was a failure because nobody bothered to ensure that the systems were all using the same units of measurement - one system was using metric, the other customary.

If something doesn't make sense to you, keeping it to yourself achieves little. At worst you learn something, at best - it's because something was wrong.

[1] - https://en.wikipedia.org/wiki/Mars_Climate_Orbiter

Ok, please submit your new record wbgt findings, for the benefit of all

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