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Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

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Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#201

Post by jameshart »

saalweachter wrote: post #175
jameshart wrote: post #142

Earlier quoted context omitted.

So you have a supply of water at 50°F - that’s 10°C (an optimistic temperature in many places). And you are using it to try to maintain a body temperature around 37°C. Let’s assume you do so by transferring heat from your body into the water enough to raise its temperature by 25°C - that’s probably overly optimistic given that it will also be warmed by the environment and the rate of transfer will be reduced as the t…

> Your body, when not working hard, produces about 200W of heat. That’s 200J per second. Minor quibble, 2000 (kilo)calories / 1 day = ~100 Watts.

Fair - I took a number for an active, awake human. You don’t produce that wattage all the time; resting and sleeping have much lower heat output; average power over a day is probably more like 100W (hence that being a reasonable average ‘healthy calorie intake’ number which I assume is where your 2000kCal comes from.)

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#202

Post by FrustratedMonky »

wiz21c wrote: post #20

fta: "Our best hope in the face of inevitable rises in heat? Cooperation. “We’ve built forecasting systems that will warn us when disasters are incoming by working together at enormous scale. We must continue to do the same.” This sentence basically says "we don't need to make less disasters, just better handle them".

I've heard this argument used to say climate change isn't happening, because there are less deaths.

Hurricanes aren't getting stronger, because there are less deaths.

But ignores we are getting better at predicting land falls and evacuating.

Responding to disasters 'better', doesn't mean disasters are not getting worse.

And there is some diminishing return, eventually the disasters will overwhelm the ability to respond.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#203

Post by jameshart »

jijijijij wrote: post #197
jameshart wrote: post #142

Earlier quoted context omitted.

So you have a supply of water at 50°F - that’s 10°C (an optimistic temperature in many places). And you are using it to try to maintain a body temperature around 37°C. Let’s assume you do so by transferring heat from your body into the water enough to raise its temperature by 25°C - that’s probably overly optimistic given that it will also be warmed by the environment and the rate of transfer will be reduced as the t…

Thank you for doing the math! At least in my area in central Europe, 10°C would be wildly optimistic in summer. I also presume when submerged in cold water, your body will start heating up , at first. So there is probably only a narrow temperature window for effective cooling. Not to mention, you may have to work and be awake to exchange the water, and being constantly wet for a prolonged time may come with it's own…

A large body of cool water works great at moving heat way from you, obviously - an ‘acre foot’ of water is 1.2 million liters - 300,000 gallons. So a fairly small one acre lake that’s ten feet deep has 12 million kg of water, which can absorb 48GJ of heat before it rises in temperature by a single degree.

The big question though is how long will that lake remain cooler than the air in the face of wet bulb temperatures around body temperature. Thermal equilibrium will win in the end.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#204

Post by netsharc »

no_wizard wrote: post #171
jijijijij wrote: post #131

Earlier quoted context omitted.

Yes. Also radiative cooling. Lawns literally suck here too, we need more trees and bushes, biomass fixation, in personal homes, for shade and drought resistance. And massive, diverse reforestation to replete ground water reserves and stabilize the local weather. We also need to massively invest in poor countries' ability to survive too. Or else conflicts will spread to us regardless of our own resilience.

I'm convinced that there is a contingent in society that has crossed both side of the political spectrum that is increasingly less empathetic to assisting poorer regions of the world as the negative effects of climate change start setting in, and its only going to grow Its anecdotal, but my very progressive friends (think: Bernie Sanders type voters) have over time subtly started expressing opinions that are regressi…

I can understand why even Bernie Sanders type voters start "victim blaming".. all humans are selfish creatures, and we sure don't want to give up our comforts more than we'd like. Recycling, switching to EVs and LEDs, well, most people are comfortable with that. Never fly to Rome or Thailand again? "But I need to..!", some will say. And sooner or later we'll start justifying their selfishness by saying it's not our fault that Indians are dying in heatwaves (then again, technically it's not my singular fault, maybe the fault of the system that's given me a comfortable life plus luxuries like trips to Rome and Thailand...)

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#205

Post by brazzy »

wholinator2 wrote: post #95
brazzy wrote: post #48

Earlier quoted context omitted.

The point is that at some sufficiently high humidity, fans and wet rags do not help any more, at all ! Combine that with sufficiently high temperatures, and it's not survivable. And will kill people with weak circulatory systems (i.e. the elderly and babies) quite a bit earlier.

Yes, the fan cannot cool. But have your ever experienced the cold water tap being cooler than the ambient air temperature? They mean that they soak a rag in cold water, from the tap, and then apply that to themselves. This will 100% help cool the person down. You could run a cold bath, take a cold shower, even drink the cold water (but not too much too cold!) If you have cold water, you can survive.

That's a big "if" in rural areas of third world countries, though.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#206

Post by netsharc »

athenot wrote: post #101
donatj wrote: post #82

Earlier quoted context omitted.

Having a rag of cold water on you will cool you regardless of evaporation. It is a thing that is cooler than the environment. The water from our taps at least is a pretty constant like 50°F

In Atlanta the tap water in summer is more like 22°C (72°F), which is coincidentally the average nighttime temperature. I could imagine that a place where the nighttime temperatures are in the mid 30s (°C) would not have any cooler water available.

Last summer there were reports of the water of Florida's beaches being bath-tub warm...

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#207

Post by Qwertious »

nicbou wrote: post #90
Qem wrote: post #64

Earlier quoted context omitted.

They face dry heat, not humid, extreme heat. These are different problems. Dry heat easier to solve.

People in Southeast Asia, on the other hand...

Are buying AC units like crazy.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#208

Post by hackerlight »

thworp wrote: post #174
hackerlight wrote: post #33

Earlier quoted context omitted.

People who live in the humid tropics are already on a knife's edge. A small increase makes the heat intolerable and you will see either mass death or mass waves of immigration. "Just build aircon" doesn't work when you're talking about people with intermittent (or no) electricity and who have an annual income equal to a single aircon unit.

All the more reason to urgently develop the world to at least the level of Malaysia / Thailand (or ~Western Europe ca. 1950). If we quit fossil fuels cold turkey it is those very same people in the tropics that will starve. But making that connection requires thinking about second order effects, a tall order for the degrowth cult.

I want to continue growing, just replace fossil fuels with renewables or nuclear in all developed countries, and subsidize the same for poor countries who haven't historically emitted much and don't have the wealth to transition themselves. There isn't this false dichotomy of degrowth vs growth. We can grow our economy without growing emissions.

https://news.climate.columbia.edu/2020/05/08/fatal-heat-humi...

The medium-term problem for these hot countries is that extreme heat negatively impacts education and economic productivity. Whenever there's a heatwave (which will become more frequent) they have to keep their kids home. Worker producitivity is negatively impacted. It's terrible for their economic development. The US and Australia and Canada continuing to pump more fossil fuels instead of simply building renewables does nothing help the average person in Sri Lanka living under 30+ degree heat. It is actively physically harming them in a very real way. It's an indirect, diffuse form of physical assault.

The long-term problem for these hot countries is that wet bulb temperatures will make it literally uninhabitable unless you have electricity and aircon, which many don't. This is not a matter of if, it's a matter of when. If we keep emitting, temperatures will keep rising, until the point that this becomes true. It is causality.

I want conservatives to think about this latter point because the consequences are mass immigration to colder countries, primarily the US and in Europe. Then the side-effect of that will probably be a rise in authoritarianism in these colder countries as a reaction to the mass immigration. None of this benefits anyone.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#209

Post by moffkalast »

_heimdall wrote: post #199
moffkalast wrote: post #185

Earlier quoted context omitted.

Well there are risks of course, and it will most likely make things slightly worse for a while with less solar power and smaller crop yields with less sunlight, but there's really no other way to fix this mess. The simple fact is that removing all of our impact in terms of just stopping release of C02 and methane (as impossible that would be to achieve with our entire society built on energy dense fuels and entrenche…

It sounds like we likely agree that there is some level of reduction that would work, but that unrealistic that people will be willing to go that far. Where we may be talking past each other a bit (sorry if I am) is the risk and reward of untested, theoretical solution that impact the entire planet. > To continue your medical analogy, you've got a smoker with lung cancer and having him quit smoking and moving to the…

I think this is a type of project where the results will never be fully possible to predict, but the same goes for what happens if we do nothing. It impacting the entire plant is kind of irrelevant imo, basically everything we do these days impacts the entire planet anyway and we don't lose much sleep over it.

The way I see it, we can either act and run the risk of getting it wrong and making a bad situation worse, or doing nothing and guaranteeing a bad situation. On a very basic level any risk is worth it if we know that the alternative must be avoided at all costs (e.g. guaranteed death). I don't think the end result will be extinction if we do nothing but reduce emissions, but there it be a major enough calamity to justify the risk of doing some things we can't fully test.

> He exercised the ability to decide what to do with his own life and body.

And later regretted it before he died. I just hope we don't regret our inaction as well.

Re: Humanity Is Dangerously Pushing Its Ability to Tolerate Heat

#210

Post by moffkalast »

adrianN wrote: post #28
ponector wrote: post #19

Earlier quoted context omitted.

Who should pay for it? No one really wants to spend money on something like that. People don't want to spend 0.1% of GDP to help survive people in Ukraine and you think they care how hot is there for the people of Australia?

Aerosol injection is not very expensive.

On a planetary scale, literally everything is very expensive.
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