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Nearly the hottest place on Earth, India swelters under intense heat wave

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Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#201

Post by allisdust »

sumedh wrote: post #149
kburman wrote: post #100

Never knew Himalayan range is so effective. India should build artificial mountain range to stop heat weave entering the region.

Maybe blow some parts of the Himalayas so the cold air can enter the Indian mainland.

If that is done, then the advantages are lost too. Much of moisture from the monsoons is dumped as snow during winter which powers all the glacial rivers because Himalayas act as a barrier for the moisture rich winds. That is why the other side of Himalayas is a cold dry desert (rain shadow).

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#202

Post by ch4s3 »

jillesvangurp wrote: post #185
mensetmanusman wrote: post #165

Earlier quoted context omitted.

This is also known as the wet bulb temperature, and it is a function of the humidity. https://en.m.wikipedia.org/wiki/Wet-bulb_temperature If I were in a position of decision making in India, I would invest in large deployments of passive radiative cooling films: https://www.3m.com/3M/en_US/energy-conservation-us/applicati... These reflect nearly all the sunlight energy and cool their surroundings night and day by co…

A wet bulb related crisis in India is used as a plot point in Kim Stanley Robinson's latest novel Ministry for the Future. The way he describes the wet bulb event is quite scary. (edit: corrected author and title, I confused this with Neal Stephenson's latest Termination Shock). Imagine something like that happening in a slum. It's the combination of humidity, temperature and poverty that is deadly. Think mass casual…

I thought the setup for that book was interesting, but it's probably his worst book IMHO (though I haven't read all of them). Normally I'm careful about attributing the actions of characters to novelists, but Robinson seems to be increasingly advocating terrorism in his books and it's getting really off-putting.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#203

Post by ianai »

dgellow wrote: post #179
pseudostem wrote: post #122

Earlier quoted context omitted.

I deployed my own design (not calculated, eyeballed) of a buoyancy based passive cooling at my parents home near Mumbai, India. It did make a measured difference of approximately (temperature meters aren't very accurate) 2 degrees Celsius. I have been reading a lot in my spare time and your blog looks like a nice read. My point is, is 2 to 3 degrees Celsius enough? From what I read is that I need to really move very…

I’m not that familiar with hot temperatures but intuitively I would think that a difference of 2-3 degrees (Celsius) when temperatures are already high at around 40-45 to be noticeable. For example if you go from 40°C to 37-38 that’s a quite good improvement if you don’t have to spend energy for this. I don’t know if that also applies to more extreme temperatures like 47°C, I cannot really imagine how that feels like…

At those temperatures heat stroke isn’t far away regardless of humidity. These aren’t temperatures to target 2-3c reductions as a safe goal, either.

Ref: lived in LV,NV for a decade.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#204

Post by germinalphrase »

jillesvangurp wrote: post #185
mensetmanusman wrote: post #165

Earlier quoted context omitted.

This is also known as the wet bulb temperature, and it is a function of the humidity. https://en.m.wikipedia.org/wiki/Wet-bulb_temperature If I were in a position of decision making in India, I would invest in large deployments of passive radiative cooling films: https://www.3m.com/3M/en_US/energy-conservation-us/applicati... These reflect nearly all the sunlight energy and cool their surroundings night and day by co…

A wet bulb related crisis in India is used as a plot point in Kim Stanley Robinson's latest novel Ministry for the Future. The way he describes the wet bulb event is quite scary. (edit: corrected author and title, I confused this with Neal Stephenson's latest Termination Shock). Imagine something like that happening in a slum. It's the combination of humidity, temperature and poverty that is deadly. Think mass casual…

He did a talk at the Long Now Foundation recently:

https://longnow.org/ideas/02021/11/10/climate-futures-beyond...

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#205

Post by eklavya »

hagen2022 wrote: post #32
nasut wrote: post #17

Earlier quoted context omitted.

Well that would be 12kWh (EU) vs. 1.8kWh (India). Multiply by population 447M * 12 kWh = 5364 BkWh vs. 1360M * 1.8 kWh = 2448 BkWh from oil. So yes, EU is spewing twice the co2 from oil. That said, the EU has probably the strongest co2 emissions reduction programs out there atm. The EU for example reduced its co2 emissions by 19% 2019->2020. India’s co2 emissions OTOH grows 4-5% each year. So in that sense they are s…

One can always compare the per capita and blame the rich world for many issues. This is nice for a debate. But at the end, poor + middle class of India suffer due to this. Sure the rich world ruined environment, but that cannot be reason to say India can do similar. The first to get affected will be the poor world (yes, incl. India) and then only the poor people in the west. I understand this is a sensitive issue, as…

The problem is that you are cut off from the reality. The poor has to live and that means we need to have cheap energy. Get off the high horse and maybe engage with your governments to understand why nuclear power is still out of reach for developing nations. Forget about sharing green power tech.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#206

Post by kibwen »

OccamsRazr wrote: post #135
zrail wrote: post #115

Earlier quoted context omitted.

How much do these things work when the wet bulb temperature is over 90F?

This would be my concern too. People fail to understand how in heatwaves there ceases to be cold air to move around. Everything heats up. It's brutal.

At that point you need to put your heat exchanger pipes underground, which is more annoying than air-based AC but not insurmountable. The temperature 20 feet underground will be about 50 F year-round. Of course, if a city of millions tried to do this all at once I have no idea how the local ground temperature would react.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#207

Post by ianai »

mytailorisrich wrote: post #154
OccamsRazr wrote: post #132

Earlier quoted context omitted.

As someone who was in Europe for one of the heatwaves of recent years, and whose appartment was in one of these older buildings designed this ways with thick walls etc., I can attest that this only works up to a point . This design relies on there being cold air for the building to retain. However, in a heatwave it doesn't even get cold at night. The result is your apartment gradually heating over a period of days /…

I grew in Southern Europe (around 30C every day in summer, more in full sun) when no-one had aircon at home and no-one had aircon in cars. It's hot, you live with it. I'm sure it's worse on the other side of the Med. It's one of the reasons the traditional 'siesta' exists and towns and villages are virtually dead until 5pm. The issue I have with aircon is that it makes people ignore the local climate and, worse, acti…

30c isn’t a point of reference for hot temperature.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#208

Post by mensetmanusman »

Retric wrote: post #197
mensetmanusman wrote: post #186

Earlier quoted context omitted.

It’s a per-unit-area comparison: https://www.betonconsultingeng.com/passive-radiative-cooling... “”SkyCool arrays work by cooling a fluid that moves below the panels and is pumped through refrigeration systems. The cooling helps reduce the run time of motors in the refrigeration system to reduce electricity consumption. All told, the SkyCool system can reject heat at about 100 watts per square meter, saving between 4…

Ok, that’s your problem it’s about 2400Wh of heat moved per day per m2. A solar panel should be collecting ~1600Wh/day of electricity/m2, but an AC can then use that electricity to remove ~4,800Wh of heat. And that’s assuming you need to remove heat 24/7/365. A solar panel can also provide electricity when cooling is unnecessary. Things get even worse if you need pumps etc to circulate a fluid under the film, which i…

Don’t necessarily need pumps, depending on what you are trying to do: https://www.abc15.com/weather/impact-earth/asu-testing-new-m...

This is what I was thinking of in the case of India :)

Edit: wanted to add, application of this technology might require government level systems thinking.

With an air conditioner, that heat being moved is being pushed to your neighbor, passive cooling technology rejects much of the heat out of the earth.

I.e., AC contributes to the urban heat island effect, the situation snowballs and makes everyone’s AC have to run even harder.

Passive cooling films are a mitigation for the urban heat island effect.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#209

Post by jillesvangurp »

ch4s3 wrote: post #202
jillesvangurp wrote: post #185

Earlier quoted context omitted.

A wet bulb related crisis in India is used as a plot point in Kim Stanley Robinson's latest novel Ministry for the Future. The way he describes the wet bulb event is quite scary. (edit: corrected author and title, I confused this with Neal Stephenson's latest Termination Shock). Imagine something like that happening in a slum. It's the combination of humidity, temperature and poverty that is deadly. Think mass casual…

I thought the setup for that book was interesting, but it's probably his worst book IMHO (though I haven't read all of them). Normally I'm careful about attributing the actions of characters to novelists, but Robinson seems to be increasingly advocating terrorism in his books and it's getting really off-putting.

I agree, I did not actually finish the book. The setup was interesting but it was all a bit too moralistic and righteous for my taste. Neal Stephenson's Termination Shock is much more fun in that respect.

The terrorism aspect is interesting though. He's not the only one that is predicting conflict as a direct result of global warming. Mass population displacements due to things like wet bulb heat events, droughts, the middle east routinely hitting temperature of over 50/60 degrees Celcius, etc. have the potential to get really ugly.

Re: Nearly the hottest place on Earth, India swelters under intense heat wave

#210

Post by kibwen »

javajosh wrote: post #188
K0balt wrote: post #98

Earlier quoted context omitted.

Even if all humans on the planet went to zero emissions tomorrow it is too late. We are now inside a feedback loop that will push temperature rise to +20c and sea levels up 200m or more within 200 years. Photosynthesis drops off to zero long before then. Geoengineering is the only way we don’t go extinct along with most animals.

Well you're in luck because it's likely we'll have a nuclear war soon, and that will put plenty of aerosols in the atomosphere, and cool things down.

Bad news: nuclear winter isn't actually a thing, so after the bombs drop we'll still be stuck with runaway climate change.
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