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'Unprecedented' alerts in France as blistering heat grips Europe

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Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#41

Post by nargek »

mensetmanusman wrote: post #37

If policy makers were smarter technocrats, they would know that passive cooling film technology exists now and can cool surfaces below ambient by rejecting sunlight and having high thermal emissivity (unlike metallic reflectors). Add this everywhere to reduce A/C and lower urban heat island effects. It’s basically performs optically like snow. Paint doesn’t work because it gets dirty too fast, films can incorporate a…

AFAIK the top of UPS trucks are mainly translucent just to allow light to shine through, so that you don't have to light up the cargo part of the truck. The cooling part doesn't seems too effective.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#42

Post by user____name »

votepaunchy wrote: post #30
DanielHB wrote: post #22

Earlier quoted context omitted.

It is hard to explain to people who don't live in tropical countries, but 16C in Scotland means the sun is still up giving some radiating heat when it directly hits you or the building you are on. 16C in a tropical country means the sun is completely blocked and no direct heat coming towards you. Think more like 16C at night feels colder than 16C during the day. The temperature in official thermometers is the overall…

> because below zero the air humidity goes away You need much colder for this to happen. Google says: Water vapor, even in freezing temperatures, doesn't instantly freeze into ice unless it comes into contact with a surface or the temperature drops extremely low (around -40°C).

I think what they meant is humidity is lower when freezing, not necessarily zero.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#43

Post by rand0m4r »

showsover wrote: post #33
rand0m4r wrote: post #31

As someone living in Spain, this is the only time of the year when I'm happy to go to the office. Yet, I think people need a tutorial on how to use the AC: it's 38ºC outside, but in my cubicle it's about 19ºC - I would be OK with 26ºC.

19 degrees is crazy, I thought that offices and public buildings were limited to 25 degrees? EDIT: I didn't search too long but I found an article from a few years ago talking about the limit being 27 degrees. https://www.elnacional.cat/es/economia/sanchez-limita-aire-a...

you are absolutely correct, the problem is that some people don't care at all (I'm working in a WeWork office)

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#44

Post by mike_hearn »

rightbyte wrote: post #29
globular-toast wrote: post #8

Earlier quoted context omitted.

The trouble is if you just retrofit aircon with no other changes you actually increase the outside temperature, possibly by more than 2 degrees[0]. This has worried me since I was a child. If everyone has AC it's a race to the bottom as it gets warmer and warmer, AC has to work harder, using more and more energy etc. You end up with hellhole cities where you can't be outside at all. It's simply not sustainable. We ha…

Oh that is interesting. A greek guy I know said to me that cities 'radiated heat' some years ago and I kinda didn't believe him. Localised to alleyways etc the effect can probably be even worse.

The urban heat island effect isn't to do with AC specifically. It's a mix of tarmac absorbing heat during the day then re-radiating it at night, a higher population density and a higher density of machinery.

The night time re-radiation has the effect of bringing the min closer to the max readings, and so making it look as if temperatures are going up, even when max temps aren't changing much. The same effect can't be seen in rural places where there's less tarmac.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#45

Post by mslansn »

moomin wrote: post #35
mslansn wrote: post #21

Earlier quoted context omitted.

I have no idea if they have their own agenda, but their ends (such as supporting private transportation and meat consumption) I support. Even if I didn’t trust them, and I don’t trust them either, the ends justify the means.

My God the radicalisation funnel produces some utter brain rot. Unsubstantiated accusations, slippery positions designed to distance your moral culpability in the consequences of your actions. Seriously, read yourself sometime.

The radicalisation of… check notes… being able of affording meat and a car.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#46

Post by AlecSchueler »

sandspar wrote: post #3
dustincoates wrote: post #2

Thankfully in Paris it doesn't look like we're going to get it as bad as was expected. It's "only" going to be 100f/38c today and 90f/32c tomorrow. Hot, but considering that just a few days ago my weather app predicted 107f/42c, it's welcome. Still, it's hot. My daughter's school actually suggested parents keep their kids home today, as they aren't equipped for this heat.

How common is air conditioning in Paris? What proportion of homes have air conditioning, either built-in or portable? How about businesses? Does Paris have sufficient "cooling stations", as in, large, air conditioned, public-friendly businesses like malls or community centers?

The more people install air conditioning the more energy we use, warming up the world even more, requiring even more AC units to be activated.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#47

Post by AlecSchueler »

mslansn wrote: post #36
1718627440 wrote: post #25

Earlier quoted context omitted.

Do you despise public transport as a concept or just the current subpar implementation? I think climate research is orthogonal to any political agenda, i.e. opposing private transportation and meat consumption doesn't follow from accepting that the climate is getting warmer and the validity of political agendas has no effect on the authenticity of climate research data.

I don’t really care too much about what happens to public transportation as long as I’m not forced to use it, which is what they want to do.

Weather analysts?

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#48

Post by rjmunro »

AlecSchueler wrote: post #46
sandspar wrote: post #3

Earlier quoted context omitted.

How common is air conditioning in Paris? What proportion of homes have air conditioning, either built-in or portable? How about businesses? Does Paris have sufficient "cooling stations", as in, large, air conditioned, public-friendly businesses like malls or community centers?

The more people install air conditioning the more energy we use, warming up the world even more, requiring even more AC units to be activated.

In terms of energy supply, air conditioning works pretty well with solar power. Normally hot days and sunny days are very correlated.

If you are worried about the local heat generated by the air conditioners themselves, there are new coatings and panels that can radiate that heat directly to space, for example https://www.skycoolsystems.com/. Also just removing a few parking spaces and replacing them with green space can help at a city wide level.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#49

Post by josefritzishere »

1718627440 wrote: post #19
mslansn wrote: post #16

Earlier quoted context omitted.

It would seem foolish to trust the temperature records from the same people who want to install draconian measures using temperatures as an excuse.

What "draconian measures"? Planting trees and installing water fountains?

You know those draconian trees. That would be some very severe foliage.

Re: 'Unprecedented' alerts in France as blistering heat grips Europe

#50

Post by AlecSchueler »

rjmunro wrote: post #48
AlecSchueler wrote: post #46

Earlier quoted context omitted.

The more people install air conditioning the more energy we use, warming up the world even more, requiring even more AC units to be activated.

In terms of energy supply, air conditioning works pretty well with solar power. Normally hot days and sunny days are very correlated. If you are worried about the local heat generated by the air conditioners themselves, there are new coatings and panels that can radiate that heat directly to space, for example https://www.skycoolsystems.com/ . Also just removing a few parking spaces and replacing them with green spac…

Yep, in an ideal world solar makes it not so bad and we're transitioning there. But my country (the Netherlands) is still about 50% powered by dirty sources and the energy transition is happening too slowly to avert the climate crisis, so let's not wave it away with solar promises.

That's also only the operation of the things, their production and transport involves global chains of mining, shipping etc. and all the solar panels would be the same on top of that

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