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India heatwave temperatures pass 50 Celsius

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Re: India heatwave temperatures pass 50 Celsius

#231

Post by Scoundreller »

the8472 wrote: post #206
newnewpdro wrote: post #200

Earlier quoted context omitted.

I don't think it's that simple at all. The principal human-appreciated effect of AC is the dehumidifying of the air when it's cooled. The dry interior air allows human perspiration to regulate temperature effectively. The AC doesn't have to cool all the bodies, it just has to keep the air dry enough.

Don't ACs dehumidify by condensing the water? If so then it means they need to get rid of the heat of vaporization, the same amount of energy the humans shed by evaporative cooling.

Right, but it does mean you just need to be in a somewhat sealed room to remove the humidity instead of constantly fighting the ever-warming walls/floors/ceiling. Of course you need to exchange CO2 and O2 to stay alive.

Re: India heatwave temperatures pass 50 Celsius

#233

Post by vishnugupta »

aq3cn wrote: post #205
enitihas wrote: post #109

I think humidity is a big problem in a lot of places in India with high temperature. In my village in easter UP in India, summer was intolerable because of high humidity and shortage of electricity. (We used to have 8hours electricity per day, but sometimes outages would happen and would go unrepaired for week to month). It was impossible to do anything but take a hand fan and use it to cool yourself. A lot of the ti…

Now days, you can get 24x7 electricity in tier 1, 2 & 3 cities. I am not sure about villages. Our country is almost power surplus nation now.

> Now days, you can get 24x7 electricity in tier 1, 2 & 3 cities

Bangalore (supposedly a tier-1 city) has regular power cuts throughout the year. Apartment residents don't notice this thanks to the diesel generator.

Re: India heatwave temperatures pass 50 Celsius

#234

Post by mikeash »

user5994461 wrote: post #227
mikeash wrote: post #213

Earlier quoted context omitted.

To riff on a common quote: if a million refugees want to get into your country and you don’t admit them, the refugees have a problem. If a billion refugees want in, you have a problem. Nothing “simply” about it.

That's a wrong statement though. One million people is a single city. You do have a problem if one million people are suddenly relocating. It has happened before for war, natural disasters or other reasons. Migrating a billion people is not a thing, for the simple fact that there isn't any human settlement any close to approaching a billion people. If you're talking about the scale of a whole continent, migratory flu…

I’m talking from the perspective of the country the refugees are trying to enter. If a million refugees are headed your way and you don’t want to let them in, you can close the border and enact strict immigration controls and you’re fine. Sucks for the refugees, but the target country has no problem aside from the emotional burden. If a billion people are headed your way, you’re fucked.

Re: India heatwave temperatures pass 50 Celsius

#235

Post by YeGoblynQueenne »

ajross wrote: post #130
jobigoud wrote: post #124

Earlier quoted context omitted.

> fatal even to fit and healthy people, unclothed in the shade next to a fan; This is scary, what's a good way to survive for someone that doesn't have access to a bunker or AC? Immersing oneself in water in a bathtub?

A tub will work, sure, as long as it's pulled from a large body of water that hasn't warmed up with the air. Hopping in the local lake is an obvious choice. But in a detached demographic sense: effectively everyone lives in a city in the modern world, and while their housing might not be air conditioned most of the major buildings are. In an emergency like this everyone would just crowd into office buildings and shop…

Air conditioning itself is a significant contributor to greenhouse gas emissions, via energy consumption:

https://www.rehva.eu/knowledge-base/rehva-journal/chapter/ai...

See the pie chart on page two: eletricity consumption from cooling systems is 17% of global consumption. The IPCC expects this usage to rise as temperatures rise.

I would also like to challenge the notion that human beings understand how to use air conditioning units. In pretty much every building I visited or vehicle I boarded with air conditioning, if the unit was on, the windows were also wide open at the same time. In Greece, where I'm from, in the summer, you can cool down just by walking past stores, with their doors thrown wide to signal they're open for business and their air conditioning blasting cool air onto the street. It may be 42°C in the shade, but in front of our shop, it's 15°! Come on in and buy our stuff! But put on your coat first.

Contemplate for a second the futility of this behaviour: air conditioning pumps heat out of a room, into the environment; leaving the windows open allows the heat to circulate back into the room. The unit typically has a thermostat, also typically set at an unrealistically low value, that would cause the user to turn on the heating in winter. The unit goes to work and pushes the warm air out trying to reach its target temperature. The warm air cycles back in from outside and tries to raise the temperature. The unit keeps working, and working, and working, wasting energy all the time. Eventually, this contributes to warming, which causes more people to buy and misuse air conditioning.

We might know how to survive a heat wave, by our clever use of technology, but we don't know how to use technology to avoid more and more severe heat waves.

Re: India heatwave temperatures pass 50 Celsius

#236

Post by Scoundreller »

inflatableDodo wrote: post #184
kache_ wrote: post #170

Earlier quoted context omitted.

Economic refugees don't have it good either. Starving and dying from disease isn't easy.

If you are travelling because otherwise you will starve while dying from disease, you are a refugee. Economic migration generally assumes that you are not likely to die from returning. I do not think it is that wise to conflate the terms.

Being too poor to not have enough food, or experiencing a crop failure, does not meet official definitions of refugee eligibility:

https://www.unrefugees.org/refugee-facts/what-is-a-refugee/

Re: India heatwave temperatures pass 50 Celsius

#237

Post by inflatableDodo »

user5994461 wrote: post #227
mikeash wrote: post #213

Earlier quoted context omitted.

To riff on a common quote: if a million refugees want to get into your country and you don’t admit them, the refugees have a problem. If a billion refugees want in, you have a problem. Nothing “simply” about it.

That's a wrong statement though. One million people is a single city. You do have a problem if one million people are suddenly relocating. It has happened before for war, natural disasters or other reasons. Migrating a billion people is not a thing, for the simple fact that there isn't any human settlement any close to approaching a billion people. If you're talking about the scale of a whole continent, migratory flu…

>Migrating a billion people is not a thing

Yet.

Re: India heatwave temperatures pass 50 Celsius

#238

Post by ricardobeat »

YeGoblynQueenne wrote: post #235
ajross wrote: post #130

Earlier quoted context omitted.

A tub will work, sure, as long as it's pulled from a large body of water that hasn't warmed up with the air. Hopping in the local lake is an obvious choice. But in a detached demographic sense: effectively everyone lives in a city in the modern world, and while their housing might not be air conditioned most of the major buildings are. In an emergency like this everyone would just crowd into office buildings and shop…

Air conditioning itself is a significant contributor to greenhouse gas emissions, via energy consumption: https://www.rehva.eu/knowledge-base/rehva-journal/chapter/ai... See the pie chart on page two: eletricity consumption from cooling systems is 17% of global consumption. The IPCC expects this usage to rise as temperatures rise. I would also like to challenge the notion that human beings understand how to use air c…

Air curtains can be extremely efficient and allow doors to stay open. That sounds like an insane waste of money and energy if store owners are not using one - are you sure you're not just feeling the 10-20% lost cold air when walking past?

Re: India heatwave temperatures pass 50 Celsius

#239

Post by wtdata »

mayankkaizen wrote: post #195
perfunctory wrote: post #186

A slightly redacted version of my earlier post. Dear HN crowd, it might not feel like it but we are quite influential. We are rich and therefore have a non-negligible command over economy. Silicon Valley is cool and people look up to us (do they? I don't really know, but wasn't Steve Jobs a national hero?) and may follow our example. Please, take the lead. Here are a few things an hornorable member of the HN communit…

India has population of over 1.2 billion people. And major part of this population is vegetarian (at least in the sense that they don't eat meat on daily basis twice a day). What if India were meat consuming nation just like US?

India is the country with biggest population density in the planet (barring some micro nation), why does everyone keep giving India a pass for having absolutely no regard for sustainability and keep exploding their population by having way more children than those they could actually provide with a good life (if not environmentaly, at least economically) ?

Should we really expect the same level of life for the children of couples that had 2 children and were able to properly provide for then, and for children of couples that had 6 children when they couldn't even provide properly for 2?

Re: India heatwave temperatures pass 50 Celsius

#240

Post by wongarsu »

Scoundreller wrote: post #231
the8472 wrote: post #206

Earlier quoted context omitted.

Don't ACs dehumidify by condensing the water? If so then it means they need to get rid of the heat of vaporization, the same amount of energy the humans shed by evaporative cooling.

Right, but it does mean you just need to be in a somewhat sealed room to remove the humidity instead of constantly fighting the ever-warming walls/floors/ceiling. Of course you need to exchange CO2 and O2 to stay alive.

But the people in the room will create more humidity that you have to constantly remove again.

Humans burning calories to stay alive creates heat, and thermodynamics that you spend energy to remove it or see the temperature rise. Whether that heat is hot air or bound as humidity shouldn't make a large difference.

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