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Comment by akgerber | Hacker News Reader

I spent summer 2018 biking across Europe & everywhere I went, from Spain to Scotland, was much hotter than the climate data I looked up on Wikipedia prepared me for. It definitely felt like the climate had tangibly changed— especially if the same thing seems to be repeating this year.

I guess everyone in Europe will be moving towards installing air conditioners, and they'll need to add peaker plants to power them on hot summer afternoons. Hopefully solar & storage will be cheap enough that it isn't too bad for the climate.

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The cruel bit here is that installing air conditioners substantially increases the per-capita carbon footprint which in turn will lead to a further greenhouse effect. It's a positive feedback loop with many components.

one saving grace is that if you couple AC with photovoltaics, you provide at least some of that power at the point of use. not much and the upfront cost is still high, but at least it's an option.

Maybe. If the average winter temperatures go up, the air conditioning will be at least partially offset by lower heating costs. Of course, there are also theories of global climate change where both the high and low extremes will increase, in which case there's a double-whammy effect.

Average winter temperatures could well go down and average summer temperatures could go up. There is no hard coupling between the two with some fixed delta, rather that extremes can get more extreme.

Well but that would stand in conflict with the greenhouse-effect, or does the C02 go away in winters?

The greenhouse effect requires sunlight to work. In the winters, the poles do not get any sunlight. The cold air from the poles will travel to make other places colder.

The greenhouse effect does not require sunlight to work. What matters is how much of the energy radiated from the surface of the earth reaches space and how much is reflected back down. https://en.wikipedia.org/wiki/Greenhouse_effect

This is true, but what with sunlight being by far the largest factor in energy being radiated back from the surface of the earth you can safely conclude that in practice the greenhouse effect is to a large extent resulting in solar incident radiation being trapped. In other words: without sunlight nobody would be worrying about the greenhouse effect. In fact, without sunshine we'd love the greenhouse effect, reducing the albedo of the planet as a whole would be the only way to survive as a species (likely we'd fail).

An easier way to understand this whole climate debate as 'a rise in temperature means there is more energy available in the atmosphere'. That energy can have many effects. It can cause local heating, but it can also move large airmasses around and if those airmasses are colder than the normal for that region the movement will cause a huge swing in temperature.

This is one of the main reasons the average 2.5 degree celsius change (which on an absolute scale would not make a huge difference in the first place, most people would hardly notice) is such a huge affair.

It can cause local variations that are a very large multiple of the 2.5 degrees, much like a heatpump does not require a whole lot of energy to move a much larger amount of energy around.

This is, in my humble opinion, the most important aspect to climate change.

Our entire civilization is built on the assumption/requirement that there are enough areas of land that will remain within certain atmospheric parameters for enough contiguous months to grow a lot of food. Technology has widened the atmospheric parameters a bit, and has increased the yield enormously.

Climate change is the result of more energy in the biosphere. This energy is in the process of increasing the (effective) random variabilities of all atmospheric parameters, globally.

Our atmosphere has always been a chaotic system, and when the necessary parameters weren't met for a given region for enough time, then a lot of people migrated and starved.

Adding more energy into a chaotic system tends to make it even more chaotic.

As you noted, these permutations go in both directions.

More unusual heat waves.

More unusual cold waves.

More unusual droughts.

More unusual rain/flooding.

More unusual storms, both warm and cold.

And all of these things globally.

I think there's non-trivial chance that climate change will, on average, cut world-wide food production by a substantial amount over the next two decades. If that is indeed the case, it will be a lot of downs and ups, just as we're seeing now, but, slowly, more and more severe.

You'd need extreme temperatures for both, though. Remember that much of Europe is close to the sea, that buffers both in winter and in summer. Continental climate doesn't really begin until you hit Eastern Europe.

For the last few years, we've had pretty mild winters. This last one, I didn't use my radiators at all because the house is very well insulated and the temperatures didn't drop that low.

Not only that. It also increases ambient temperatures, which adds to the local heat amplification already occurring in big cities due to dense concrete buildings and streets.

I hope that Europe doesn't ever reach the same level of insanity with regards to air-conditioning that you see in, for example, Florida. The last time I visited (admittedly 20 years ago) I remember having to walk outside of shopping malls / supermarkets for a few minutes to warm up, having been subjected to the frigid level of AC inside.

That’s something that can be solved by law.

Been to Texas in summer last year (it was very hot outside) and I found it ridiculous how low the temperature inside was: most Europeans on the conference were complaining, we had to wear light jackets inside.

Then, I went to India (also in the summer): it's even worst (even colder inside and in the taxis).

These kind of things just to above my cultural sense of logic...

I think a big part of the "all kids do is play inside" thing people like to complain about has to do with everyone having their AC on all the time. If its hot inside and hot outside, you go play outside. If its hot outside and cool inside, you sit on your ass and look at a screen.

Heating a house is much more expensive than cooling down a house [1], so if avg temps rise total carbon footprint due to temperature control will most likely fall. A very small silver lining to a very shitty situation.

[1] https://www.quora.com/Why-does-it-cost-more-to-heat-househol...

If I recall correctly, global "warming" is an average and changes in temperature will increase both ways so might end up having to heat more for short period of times.

Global warming is an average indeed, but moving that average for a localized area costs energy, usually in the form of carbon expenditure.

Yeah; we have our thermostat target a pretty large window. I looked at at the report for May, and it heated and cooled most days.

That doesn’t seem normal (better data now, or more fluctuations?)

That article is just saying it's cheaper to move heat than to generate it from electrical resistance. You can buy heat pumps that work both directions, allowing you to heat in the winter and cool in the summer.

My main complaint about AC and the reason we rarely use ours is that while you can heat a house very quickly, air conditioners are really only good for maintaining temperature. They have a hell of a time cooling adequately when "properly sized". So if I want to use the AC, then I have to give up on having open windows ever, which is not something I'm interested in.

I don't think AC is that bad. I have a tiny window air conditioner in my apartment. When I get home from work it's more than 80 degrees in there. After the AC has been on for an hour or two, it gets down to a reasonable 76 or so. It's in my bedroom so when I close the door to go to sleep, it gets much colder (probably 68).

I believe I read somewhere that a "properly sized" AC unit should be able to cool a home 2F / hour. I could be wrong on that, but my personal experience lines up with that pretty well.

If the weather is such that you need AC or heat, why would you have the windows open? Add humidity to the mix and open windows become even more problematic.

An oversized AC is going to run more if you have your windows open when it's hot out although with humidity may actually work better as it'll run long enough to pull out some moisture (latent cooling).

If the issue is around fresh air your average pre-2000 house breathes plenty with closed windows and newer homes tend to have active ventilation (e.g. energy recovery ventilators).

I feel like I must be missing something or you live in a warm-temperate climate such that a heat pump heats faster than it cools (heat pumps go way down in heating efficiency as it gets cold out and most work very poorly when it's much below 0°F).

The temperature generally swings something like 20F during the course of a 24 hour day. At night, I am quite content to have the windows open. During the day, I'm not around so why bother cooling the house. Then when I get home from work, it'll take the rest of the evening to cool off the house, at which point I might as well have just opened the windows and let everything cool off naturally.

Contrast that to the winter, where you can quite easily have a whole range of temperatures throughout the day based on being home or away and dropping the temp down at night while you sleep.

Heat pumps I'd guess work quite well over the same delta range that summer AC usually operates in (30F probably, even on the hottest days).

Beyond that, natural gas or propane is going to be much more cost effective.

Ah that makes more sense, thanks for helping me to understand the open windows viewpoint.

For me electricity is less expensive during the day (solar) and my house is well insulated so it takes fairly little to combat the heat gain during the day compared with letting the house heat soak through the day and then try to cool everything off in the evening. There's also often more humidity in summer so I'm trying to dehumidify at the same time and an adjusting AC (e.g. variable refrigerant flow or just a variable speed on the compressor) can run at lower consumption for longer to meet both needs at once.

Well, air-conditioning is the one electric consumption which can be perfectly driven by solar energy. Solar production capacity is expanded constantly and in Germany we are already at the level where during sunny days, solar can drive like 40% of the grid.

Carbon is obviously a problem longer term but immediately, air conditioners generate heat.

A city full of air conditioners is that much hotter. We're ploughing energy (even renewable) into the air and that's making summer that much hotter. We need to stop.

It would really be better if we promoted more passive solar design instead of more AC.

We used to rely a lot more heavily on vernacular architecture. It is possible to design a space that needs little in the way of active heating or cooling to stay comfortable.

I don't know why this isn't more widely promoted. I sometimes feel like I'm the only one who has thought of this obvious answer and I have no influence in the world, so I'm just howling into the void of the internet to occasionally comment on it on HN where it often then gets dismissed on some excuse or other.

But that doesn't solve the heat problem for everyone who's living in a house that's already been built, and I don't think you're suggesting to rebuild all the existing housing to have passive cooling.

It would be great to see this type of preparation put into new builds.

But that doesn't solve the heat problem for everyone who's living in a house that's already been built

I have a serious medical condition. Years ago, while getting divorced and crammed into a single bedroom with my two teenaged sons fir nearly a year in Georgia, we discovered that getting rid of all cardboard boxes from food items stored in our room reliably and consistently dropped the temp 5 degrees Fahrenheit, lowered the humidity and stopped the invasion of roaches. I am routinely told I'm full of shit for telling that story. It's merely an anecdote.

I've lived without upholstered furniture for years. I currently have no carpeting and no mattresses. We remain strict about removing cardboard and papers from our rental.

I'm in a hundred year old building with no AC. When things get hot, other tenants open their window and door trying to get a cross breeze and are clearly miserable. We just open the window. Once in a great while, I will go run errands or spend time at the library to reduce the number of bodies in our cramped room from three to two to bring down the temperature in our room.

I've lived this way more than a decade. I'm an environmental studies major who wanted to be an urban planner as my dream career.

I get ignored, mocked, dismissed, attacked, treated like I'm stupid and crazy and have no idea whatsoever what the hell I'm talking about.

The world treated me with potentially deadly callous disregard while I was deathly ill and homeless. Now its bullshit misogyny and classism is causing it to continue to turn a deaf ear to suggestions that actually work.

While the world burns and wrings its hands I get on with making my life work. It's increasingly hard for me to believe people actually want to solve this. If they wanted to solve this, they would jump on such anecdotal evidence, do some research to confirm it and start spreading the word.

I've been on HN nearly a decade. I appear to be the only woman to have ever spent time on the leader board here. Men here routinely get told they must be smart if they have a lot of karma. I routinely get told I'm a fool obsessed with worthless internet points and shut up.

You don't have to rebuild the entire world. Just make some lifestyle tweaks.

But it won't happen because I'm a woman and everyone wants to explain to me why I shouldn't worry my silly little head about such things and I simply don't understand how anything works.

I don't understand your comment, because I don't store "cardboard boxes from food items" and don't know of anyone who does. I may have some cardboard in my recycling bin from Amazon packages occasionally, but the food I buy isn't stored in cardboard.

It's also unclear what your comment is railing against exactly. Cardboard, or upholstered furniture and rugs? Are you saying that your home is somehow cooler because everyone else is storing lots of cardboard? How much cardboard does one have to store in order to elevate indoor temperatures?

Of course, I can understand about living into a temporary apartment with moving boxes stacked everywhere. Cardboard is an excellent insulator, so obviously living in a tiny room insulated with cardboard is going to bring up the temperature. Not a common situation, though.

You don't ever buy:

Cans of soda in cardboard boxes and leave them in the boxes?

Cereal in cardboard boxes and leave it in the box until it used up?

Cookies, crackers, etc in cardboard boxes and store them in their original cardboard box until you are done consuming them?

Cake mixes, instant meal prep items, etc in cardboard boxes and leave them in the box (that has the instructions on the outside) until you are ready to actually cook it?

I mean, it's possible to just buy meat and produce and so forth and never bring home a food item in a cardboard box, but I'm quite shocked to hear that you never buy such and none of your friends do either. That seems statistically unlikely to me if you are an American or live in most developed countries.

No, I don't eat cereals (though I sometimes make my own granola), cookies, crackers, cake mixes or instant prep meals. I try to stay healthy and not consume heavily processed foods. I make cakes and meals from scratch by hand. I do have dry pasta that comes in thin cardboard containers, but that's the only thing I can think of. Thinking about my girlfriend's house or our friends' houses, they don't hoard cardboard either. We're all in the US. I also lived in Europe for many years, where this also didn't happen.

But that's all immaterial, because I don't at all buy the argument that the average person would hoard so much cardboard that it would have an effect on indoor temperature. So I still don't understand your comment.

Cardboard isn't the only thing. Carpets, curtains, upholstered furniture, cheap pressed wood furniture, shelves full of dead tree books, walk-in closets full of clothes, stacks of towels and bedding etc all do the same thing.

"When [hay] is baled at moistures over 20% mesophilic bacteria release heat causing temperatures to rise between 130°F and 140°F. If bacteria die and bales cool, you are in the clear, but if thermophilic bacteria take over temperatures can raise to over 175°F,”...

Most wet bales catch fire within six weeks of baling, Hartschuh says.

https://www.drovers.com/article/avoid-barn-fires-let-hay-dry...

Compost heaps also give off heat. So we know -- and this is well established fact, no need to listen to my "nutty" fucking personal anecdotes -- that rotting materials give off heat. In fact, they can give off so much heat as to start fires. So this is not an insubstantial amount of heat.

I got to see firsthand under fairly extreme conditions how this impacts comfort at home. I was sharing a single bedroom with my two teenaged sons. I had little control over what was in that bedroom. It was supposed to be a temporary situation. It was filled to the gills with furniture, carpet, blah blah blah.

Just coming home and taking all the sodas and snacks out of the cardboard box consistently dropped the temp by 5 degrees Fahrenheit. There was a thermometer in the window, so we were able to check.

After two or three incidents where we removed all the cardboard boxes from the room and the room went in short order from unbearably hot and muggy to comfortable enough where we could sleep, it became our policy to pull everything out of cardboard boxes and trash them as soon as we brought home groceries.

I currently live in SRO. It's more space than when we shared a bedroom at a relative's house and we have more control over our space here than we did there. We still remove bakery cookies from the cardboard box when we get it home and similar. We don't keep mail sitting around. All junk mail is promptly trashed.

We don't have a trash can. When we were living in a three bedroom, two bath apartment, we noticed that food sitting in the trash similarly raised the temperature in the house and also made us feel ill because me and my oldest son have a compromised immune system. It became our policy to take trash out promptly following meals. We still do that and we do not own a nasty ass trash can.

But I generally don't bother to go into all the details because I am consistently given absolute shit by the entire goddamn internet and treated like a total fucking idiot rather than having people ask for more details or express genuine curiosity or whatever. It's always "That's stupid." or "That doesn't make sense." Or "I don't believe you." or similar.

Meanwhile, people are dying in heat waves, but, meh, actually figuring out something useful isn't a priority. No. Treating some poverty stricken woman like absolute shit and like she couldn't possibly know any fucking thing of any actual use -- that our priority.

The worldn't isn't going to hell in a hand basket because there aren't any solutions. It's doing so because people who currently have money and so forth need to cater to their ego far more than they want solutions.

Were you able to test whether this was indeed heat generated by these items, vs their simple mass acting as a thermal reservoir?

On a typical summer day where I live, it cools down significantly at night and many open their windows to cool down. The daytime indoor temperature is later strongly influenced by this overnight cooling effect. Now, a bare room cools down very quickly, while a room full of mass will retain the heat of the day for much longer. Classic passive solar design working the wrong way round, if you will.

Mattresses, bedding, & cardboard all absorb moisture from the air, while food scraps are moist by themselves, so each could retain an appreciable amount of heat. They could even be contributing additional humidity if they absorb moisture during the hot day & release it in the cool night.

I was able to check a thermometer and note a consistent 5 degree Fahrenheit difference compared to before removing them and after removing them. I was able observe that the room not only felt less hot, it felt less muggy. I was able to observe that the large roaches endemic to Georgia stopped showing up when the cardboard was removed.

I don't believe their mass taking up space explains it. I believe them giving off heat like a rotting compost pile is vastly more likely.

But feel free to make me look like idiot by testing it under lab conditions all scientifically in a way that I was in no position to create as a desperately poor divorced single mom just trying to get to sleep at night by removing the cardboard from my room because it actually helped.

I didn't say it didn't work. I was attempting to express some curiosity about the mechanism of action. It can be useful to know why it works, so I was curious.

And I answered your question to the best of my ability -- in spite of your track record of first attacking and dismissing me elsewhere before asking questions about the mechanism.

I get ignored, mocked, dismissed, attacked, treated like I'm stupid and crazy and have no idea whatsoever what the hell I'm talking about.

I had to read your comment four times to develop half an idea of what you were trying to say. You could be very intelligent with something valuable to contribute to the discussion- but if your point is not made clear, people will struggle to see that.

Oh, sure, I have nearly 45k karma on HN between my two accounts, but I'm merely inarticulate. It couldn't possibly be that I sound incoherent at the moment because I'm frothing at the mouth frustrated at the bullshit I constantly have to put up with here. That couldn't be it.

I can't have a conversation with someone who is self-professedly frothing at the mouth & incoherent with rage. I'm just not that good, & I'll own that. So I guess all I can do is wish you the best of luck.

You could up your game and simply say nothing rather than continuing to poke at someone who is obviously upset so you can get in additional digs about how it is all their fault they fail, no one owes them anything and their expectation of being met halfway socially is clearly ridiculous.

If you own your house and need a new roof then installing one that reflects sunlight will really drop the interior temperature during the summer.

France actually enforces a law whereby every new construction need to be well insulated (rt2012 at the moment). To give an idea, to comply to this rule you need at least 15cm of styrofoam on the outside walls of your house. The next rules are coming next year, rt2020, where the construction need to be energy positive. So you will need solar panel, or heating system which give more kWh than it consumes.

Moreover there are funds available when you want to improve the thermal efficiency of your old house. I got my paid half of the bill to get a new heating system for example.

We have similar rules here in Germany. I live in a fairly modern, well isolated house. To comply with all these requirements, we build more and more houses with floor heating here. It's easier to efficiently heat that way using heat pumps, for instance. I got the impression that on our upper floor the heat is so well conserved that we basically aren't able to cool the house down anymore during these heatwaves. It takes about three days after the heatwave has passed to get back to normal levels even when all windows are open all the time and a fan blows air through the whole building. That's a real problem.

Well that's the drawback, it is designed to keep the cold/heat outside the house, but once you let the heat inside in summer, you have a hard time to cool it down. It really is designed for winter.

What i don't get in these rules, is that they requires the house to be sealed, and void of air leaks. As it is sealed, there is no natural air flow anymore and you need to install a system which regenerates the air: it gets the air from outside and vent it inside. It just blows my mind.

I find it so unnatural that i only buy old houses, where I am free to choose the insulating materials and techniques. I am against these petrol based materials which release chemicals in your house.

Reads both your comments. Scratches head. Wonders if you are for or against what I'm saying.

> It is possible to design a space that needs little in the way of active heating or cooling to stay comfortable.

I get your confusion. I was actually reacting to this part of your comment specifically. I am for what you are saying. I just wanted to mention that modern buildings aren't always designed like that. In fact, where I live, houses seem to be increasingly designed to only keep the heat in, not let it out — as rightly pointed out above. That's a problem. We basically can't stay comfortable in summer sometimes. It's not pleasant sleeping on the upper floor during a heatwave and there's little we can do other than buy an AC (which we won't).

As a sidenote: our company just finished a new building which is designed in a similar way, but has active cooling via the heat pump/floor heating system. I hope that will work better than what we have in our private home.

Thank you for your comments herer.

There are myriad things that impact both actual temperature and perceived temperature. I don't even try to talk about any of the more "woo" sounding things that impact perceived temperature.

I'm just talking about well established design principles that were a time-honored tradition globally until recent decades popularized throwing money at the problem, using insulation and adding AC to shittily designed buildings. And I get nothing but grief most of the time.

Tempted to start blog number umpteen to bitch about this in specific. I'm calling it "While The World Burns." Maybe if people here keep pissing me off, it will actually get content and traction and yadda.

Historically, people were only interested in rubber necking at what a goddamned social train wreck waiting to happen I was. Maybe I can harness that bullshit for a change instead of trying to avoid it. Swim with the current, not against it.

Would you care to expand ? I know that there are architectural trick to improve the heat management, for example i plan to plant a tree which will grow big enough to make shade on my window during summer.

But personally, I did not see yet an old building in Europe which is both warm in winter and cold in summer jusy by itself. The new insulation materials are really good now, there is no comparison with old techniques. My parents house is 200 years old, made of a wooden frame and brick. It is incredibly cold in winter, so cold that we need to burn wood as central heating is not powerful enough.

Here are some resources to read up:

https://cleantechnica.com/2018/03/31/passive-solar-house-des...

https://en.m.wikipedia.org/wiki/Passive_house

Given increased heat from global warming, we can also borrow techniques from places like Mexico and the Middle East for cooling a house using air flow. For example:

https://en.m.wikipedia.org/wiki/Solar_chimney

https://energyeducation.ca/encyclopedia/Solar_chimney

We've been doing this around the world since well before we invented AC. We just seem to have conveniently "forgotten," never mind that these techniques are actually still in widespread use.

You might like [1] and others in that vein. The passive house movement seems like a big deal in a few parts of the US (e.g. Northeast and some parts of the West coast). AC ends up being an important part of these homes as they're sealed so well that human-caused humidity (both direct and from showers, cooking etc) needs to be managed. You can get by with the equivalent of a small window unit for a 1500 square foot+ house though.

[1]: https://www.greenbuildingadvisor.com/

Yes, you describe exactly the kind of house I live in. The problem with the upper floor is that there's a skylight which you can't shade. The sun can shine on the floor (with the floor heating underneath) and warm it up all day. You don't even need to open a window to let the heat in.

The air ventilation system uses a heat exchanger to keep the heat in during winter. I am still not sure as to what it does during summer. It surely doesn't feel like it makes it actively hotter, but it also doesn't cool it down.

We are required to have this system running all the time (on the lowest level). Otherwise the house would begin to mold quickly as there is absolutely no natural air flow when the windows are closed. In fact, I once deactivated the system because of bad air quality outside. It was unbearable within about two hours inside. It's really a bit weird, but on the other hand, I like that I don't have to think about opening the windows to ventilate the house and it helps keep the heating costs low during winter.

> It takes about three days after the heatwave has passed to get back to normal levels even when all windows are open all the time and a fan blows air through the whole building. That's a real problem.

I've experienced similar issues in the UK. It's a worse problem than being cold in winter - I can just wear more layers. Not being able to cool your house is frustrating as you can stick your hand out the window and it feels cool, but you're sweating buckets at 2am

You could get yourself some US-style porches.

One of the reason the US is porch-crazy is because historically it was too damn hot here. Rather than trying to keep the house cool, you said to hell with it, and spent as much time on the porch as possible, even sleeping on it when the house was too hot at night.

In the Deep South, deep wrap around porches also allowed you leave windows open on two sides of the house for a cross breeze, even in very rainy/stormy weather.

They still sleep on porches in India and "porch sleeping" was common across the US until not that many decades ago, even in New York City where they would sleep on the fire escape or roof in hot weather.

> the climate data I looked up on Wikipedia

For travel abroad, I got into the habit of checking https://weatherspark.com. They have very well done charts that give a really good idea of how it's like "over there".

(Just a satisfied user.)

Last summer was quite an outlier...Europe was extremely dry and hot. So much so that previously unknown archaeological sites became apparent when all the grass died.

Last year was definitely exceptional in Scotland - it didn't rain for about two months - usually two weeks of sun without rain would be a 'heatwave'.

Mind you - earlier this week it was 12C and raining here - so back to proper summer weather.

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