How hot is too hot for the human body? _Heat plus humidity gets dangerous fast_
theconversation.com
theconversation.com
I have to respectfully disagree that those conditions are near the limits of human endurance. My own experience working outside in all kinds of weather causes me to see that temperature/humidity combination as fairly mild (normal summer temps for June/July) and easily survivable since I personally have known many people of all ages who manage to go about their business with no ill effects in conditions more extreme than that here in Texas. Current conditions here today were 103F (>39C) with heat index due to humidity making it feel like 106F (>41C). I worked outside all day and I am over 60 years old.
I know that our world is facing extreme conditions due to human-caused climate change and I see the effects here locally even this summer as we are firmly in an extreme drought with no rain in the forecast for at least the next 10 days.
Overall though I think humans are quite resilient and smart and that we will find a way to mitigate the damage that is already built in and to minimize consequences of further damage. I have to believe that as an organism, we will find a way to adapt to whatever we manage to create or destroy.
I believe it is probably more accurate to frame the problem as one where vulnerable members of a population will be much closer to their endurance limits over the next few decades. The human race though will adapt. Vulnerable members could be defined as those who have medical issues or those who have spent large parts of their lives indoors where the range of temperatures that they normally see is very small. They have not hardened their constitutions to the actual physical conditions of temperature and humidity where they live and work because they shelter inside year round instead of going outside to take it all in.
I think we can see examples globally of populations that have lived in what many of us in the developed world would consider extreme conditions with no hardships. They manage their limited resources to take fullest advantage of whatever meager resources their local environment provides. They will serve as a lesson to the rest of the world as to how to adapt as everything changes.
Humidity is a _large_ part of what makes it uncomfortable and dangerous, and you don't appear to be mentioning much about humidity here. Heat index is a function of both, but I don't know the formula (and +3 degrees F can't be very high humidity I don't think).
I live in Phoenix, and it gets to be near 120 quite a few summer days. It's basically just annoying, as long as the humidity is low. When it gets high, it's _way_ past just annoying, and high humidity I think is more like 50% during those times, typically.
I live in N Texas but have been to Phoenix during July and found Flagstaff a lot more hospitable. I've lived and worked all over this state, most of the western US from the canyon country of the Four Corners area, to Oregon's mountains to Louisiana's swamps, and eastern Montana to Laredo. I spent all of my early years working outside from sunrise to sunset doing manual labor jobs before I went to college.
I lived in high humidity in Houston for 10 years and, like USA Today's weather summary page described it one time, it was oppressive in summer.
High humidity is a problem but humans live in extremely hot and humid areas and they live in extremely hot deserts and cold tundra as they have for thousands of years.
It isn't that I'm not seeing the problem raised by the article, it is that I think that people who spend a lot of their time outside during the year will have fewer issues with high heat and humidity than those who spend most of their time indoors during the temperature extremes.
We know that our environment will be hotter, that some places will be drier while others will be wetter, and so we should be trying to adapt ourselves to those conditions instead of fighting them. Use the skills that people who currently live in these environments employ to help us all adapt.
In addition, we should focus our knowledge and skills on changing our own lifestyles and expectations so that we can make the changes necessary in our developed societies to bring these climate changes under control as swiftly as possible.
Sorry if all this sound incoherent. I've been up all day and spent most of the day in the sun. Maybe I'm dehydrated and my brain is taking out the mental trash.
If "smart" can be the opposite of "dumb", I have seen that for the sake of "resilience" people take shelter in the "dumb" side (so "smart" and "resilient" live also in a counter-relation of hindrance, not just in the happy reciprocal support): so what causes resilience, encouraging the "dumb" phenomenon (akin to the "stupid" in Cipolla), is the highest threat to civilization and society.
I was compelled to reread what I had written so that I could decide how your analysis fits with what I wrote.
When I mentioned smart I was trying to say that humans have the capacity to solve problems by identifying their causes and designing workable solutions. Resilient in this context was intended to mean that even when we fail to understand a problem to the extent that we can design a solution we manage to stumble into a situation where we are able to survive even if that means we ignore the problem and just move to more hospitable environs.
I agree that choosing resilience can mean always taking the easy way without ever addressing a problem or trying to understand why you had to change and that it does have serious downstream consequences for society and civilization. We have to accept the challenge of solving hard problems by working together or we will inevitably continue to load all the bad consequences on those groups least equipped to deal with them.
> Scientists and other observers have become alarmed about the increasing frequency of extreme heat paired with high humidity, measured as "wet-bulb temperature" [...] People often point to a study published in 2010 that estimated that a "wet-bulb temperature 35°C" – equal to 35°C (95 F) at 100% humidity, or 45°C (115°F) at 50% humidity, would be the upper limit of safety, beyond which the human body can no longer cool itself by evaporating sweat from the surface of the body to maintain a stable body core temperature
> [A new study gathered] young, healthy [individuals] into the Noll Laboratory at Penn State University [... The] upper environmental limit is even lower than the theorized 35 C[: i]t’s more like a wet-bulb temperature of 31°C [ - t]hat would equal 31°C (88°F) at 100% humidity or 38°C (100°F) at 60% humidity
I had to editorialize a bit the writing around the numeric data, because it was very confusing in the original.
A graphic shows that such "average critical environmental limit for young men and women at minimal activity" at the lowest humidity level is 50°C (120°F)...
..Summing up, roughly 30°C at 100%, 40°C at 50%, 50°C at 0%.
> Staying well hydrated and seeking areas in which to cool down - even for short periods - are important in high heat
> A recent study focusing on heat stress in Africa found that future climates will not be conducive to the use of even low-cost cooling systems such as “swamp coolers” as the tropical and coastal parts of Africa become more humid. These devices, which require far less energy than air conditioners, use a fan to recirculate the air across a cool, wet pad to lower the air temperature, but they become ineffective at high wet-bulb temperatures above 21°C (70°F[, at 100% humidity])
Maybe more modern people are becoming wimps from the air conditioning. (My wife and I both attended some schools that were not air conditioned, and it's not like we're ancient - In my case, it was due to incompetent months-long repairs by the Austin schools; In her case, it was just a South Florida school that didn't yet have AC.)
I expect there's a substantial geographic and occupational distribution of heat tolerance, but this research consists of people in a single area, so it doesn't catch that. That said, heatstroke risk is deadly serious, but fairly easily avoided with a few minor precautions. (Maybe a few more than Bear Bryant used with his famous Junction Boys workouts - https://en.wikipedia.org/wiki/Junction_Boys)
I guarantee you that the average farmer, rancher, or oilfield or construction workers can withstand more than these results would indicate - if that were not true, we'd lose many more to heatstroke than we do...
Their lab can't test what would kill people. They can only test conditions that risk heat stroke.
So you seem to agree with the results of the experiment, but you appear to have missed it in your eagerness to call people (not sure who, exactly) "wimps".
Well, to be fair, the poster wrote the expression "«wimps from the air conditioning»", which I would judge as quite understandable in its apparently intended scope and aim.
Unfortunately, the expression, pushing the idea of "buffers anytime", hides the opposite reality of the impact that undesirable conditions have on performance.
Now OK I am not a "climate denier" but I feel the need to remind Northern hemisphere people that it's Summer. That's all I'll say on that topic for now.
You are paradoxically right to remind us, because some of us are puzzled about this climate we seem to be thrown in in usual places. I have never in the past summers had to go at 1500m altitude (4000..5000ft) to say "ok, now the conditions are comfortable enough", but for exceptional days.
Oh, I do remember that evening many years ago in which I came to doing absurdities to get "at least a ludicrous idea of a tiny increase of fresh air" in the unbearable weather. It was summer, all right. It lasted dozens of hours, not months; it was August, not May.
I'm just learning now that I died.
> On Thursday some 1m pilgrims will begin the annual haj to Mecca in Saudi Arabia [...] But ... those who make it to Mecca will face temperatures above 40°C, which can play havoc with the human body. [...] Climate models suggest that, if global temperatures rise by 1.5°C above pre-industrial levels, lethal heat exposure during the haj will become five times more likely. A rise of 2°C increases the risks tenfold