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Chilling Effects (astralcodexten.substack.com)
167 points by Amorymeltzer 89 days ago | hide | past | favorite | 136 comments

Subsaharan African desert heat cold deaths make perfect sense if you are aware of the side effects of the lack of moisture and vegetation - low thermal mass. There is a reason desert mammals have fur and desert reptiles burrow - it drops fast and low in the night. If you go from minimally dressed in the day for heat from inexperience or poverty and are ill-prepared you die a death that sounds utterly absurd to pop cultural assumptions about the desert.

Combine that with jungle-savvanah-desert "exotic foreign wilderness" conflation. The jungle you really do dress scantily for given humidity, temperature, and most importantly the exact opposite thermal mass situation. There is a reason desert dwellers prefer covering garments beyond just sun reflection.

Greenland I can only guess as possibly related to volcanic warmth and being used to dressing for warmth combined with familarity with hypothermia's symptoms including feeling hot. If you are used to dealing with getting so cold you feel an urge to strip naked and dive in the snow you may double down on heat because it is usually cold. But if it is actually heat this time you die an absurd seeming death. I also assume heat deaths exclude fire related deaths.

This makes a lot of sense to me. I live in the Mojave Desert at about 3,000’ above sea level. The fall and spring transitions pose this exact risk. Today, for example, I’m looking at high of 80F but overnight we dropped to 39F and our humidity is hovering around 15%. Everyone jokes about it being a dry heat on those 120F days, but I’ll tell you what - dry cold is painfully colder than I could imagine and at much higher temperatures. Growing up in Massachusetts it was cold and humid and completely different. Here you can feel the heat pulling off you at 45F and it will feel sub-freezing. It’s weird to both need to keep water, so I don’t die of dehydration in heat, and a coat, so I don’t freeze to death, in the car at the same time. The desert doesn’t offer margin for error.

I think for the cold extreme it's less likely confusing too-cold with too-hot, and just the same as your African desert example. People without experience in the heat won't be able to tell when it goes from uncomfortable to dangerous due to inexperience. We're more than capable of bearing deadly heat emotionally, and so if you don't know what that feels like you'll just keep going until you get heatstroke, which will also be a new experience for an Icelander I assume. For those new to extreme heat, the sheer amount of water required to stay safe is usually underestimated.

I live in a desert and I’m very active outdoors, even in the summer, and you’re totally right about the misjudging of being safe. First is the confusion people have about clothing choice. You can tell the tourists at Death Valley because there in shorts and short sleeves while those that live here are in pants and long sleeves. Also, water consumption as you point out- I do summer hiking/trail running in the mountains around here and it’s trivial to drink a gallon of water. The biggest distance limiter is the weight of the water you need to carry.

I assume a lot of heat related deaths are mostly due to heat stroke and cardiac stress caused by it. People can easily live in high heat conditions (see deserts, for example), but if they're not used to it, it quickly becomes problematic. You can see the effects any time a heat wave hits a usually mild climate.

Cold can kill, too, but it usually hits the very poor and those caught in a bad situation ; heat stroke, on the other hand, can be pretty subtle. I can imagine someone who thinks of 20°C as hot is rather vulnerable to it.

> jungle-savvanah-desert "exotic foreign wilderness" conflation


As with most data problems, the quality of the data is always the weakling.

I think the quality of the data for this analysis is just poor (the analysis is good, but the data is really questionable), there's no way we're going to figure this one out using the data we have for it in my opinion.

As an aside, I wish that absolute numbers were also presented. Comparing things in relative ratios gets very confusing to reason about.

People continue to point out the (widely known) negative effects of global warming, but how are we so confident that the net effects will be long-term negative?[1] It seems to me an extremely complicated calculation which doesn't merit extreme certainty in either direction. Here are some of the positives of global warming:

- Statistically, an order of magnitude more humans die from colder temperatures than from hotter ones (as discussed in this article). So hotter temperatures could easily lead to net lives saved, at least in this area.

- Hotter temperatures and higher CO2 in northern/arctic areas will increase (net) crop yields substantially. Many areas which formerly weren't hospitable for certain types of crops will suddenly become so. This isn't so surprising since CO2 is an input to photosynthesis.

- Global warming will free up northern trade routes and make potentially millions of square miles of land more habitable for humans.

- The distribution of global temperature increases is expected to be tilted towards colder areas (that is: higher temperature increases in colder regions than in hotter regions). This means we get to experience the positive effects of global warming disproportionately to the negative effects.

- Slight temperature increases might even hedge against long-term climate risk: we are technically still in an ice age, and there is long-term tail risk that we will recede back into a deeper one within a few millennia. So how do we know that stopping CO2 emissions won't make human climate long-term worse?

- Even from an ecological standpoint: hotter climates will positively impact some species (including species which don't even exist yet!), while negatively impacting others. It seems to me a general rule of thumb that more life flourishes in hotter climates than colder ones. So why be so confident that the net effects of global warming will be long-term negative to animals, en totale?

Of course, the negative effects of global warming (flooding, rising sea levels, etc) are well-known, so I omit them. My point is not that global warming is definitely a net positive; it's that it's not clear why there is so much confidence it's "definitely" a net negative.

[1] Credit to David Friedman for helping point out many of these things.

You mean the immediate effects on you civilization, that is extremely optimized for the current climate? Or the long term effects?

Because the immediate (up to decades or even a couple of centuries long) effects will be overwhelming bad. There's just no chance we will end with a climate that is better than the one we optimized the hell for. There will be almost no positive effect on that horizon, that's how extreme optimization works.

About the long (after a century or so) effects for humanity, I really doubt anybody knows them. Humanity will optimize itself for them, and make lemonades out of lemons anyway it can. For nature, it's still too short a timeframe for it to adapt, and global warming means a loss on diversity on a several millenia horizon; the same happens every time there is a large climate change.

(About that new land for agriculture, plants need solar radiation, and that area has little of it. That's why it's frozen.)

> Because the immediate...effects will be overwhelming bad. There's just no chance we will end with a climate that is better than the one we optimized the hell for. There will be almost no positive effect on that horizon, that's how extreme optimization works. [Emphasis added]

This just seems like dogma to me. Of course there will be both negative and positive effects. The question is: which is greater?

Suppose I "optimize" my life for $60K/year income, but suddenly get a job which pays me $80K/year but with longer work hours and less interesting work. Question: Is my life definitely worse because my current optimization will be disrupted? The answer is that it's completely unclear. $20K more per year is good; less interesting work is bad. We need better models of what we're going to do with the money, and exactly how less interesting our work is going to be.

W.r.t. to global warming: some of our existing "optimizations" will no longer be necessary, since life will just be easier in certain ways (e.g., more crops and ecnomic opportunities in the northern regions which currently make human living very hard). Some of our existing "optimizations" will fail, and need to be adjusted (e.g., areas where the sea line is expected to rise).

The question is: why think "there's just no chance" (<- your words, not mine) that we're going to be net better off in the long-term?

> Even from an ecological standpoint: hotter climates will positively impact some species (including species which don't even exist yet!), while negatively impacting others.

The worry isn't that global warming will be bad for animals, you're right, there will be winners and losers, likely in comparable amounts. The worry is that it will be bad for biodiversity, a resource that is extremely slow to replenish (even taking into account these new opportunities). On the edges of the curve, some animals will be huge winners, and some will be huge losers. 10xing the populations of some species while others go extinct is only a net null on the very surface, it's still a huge loss diversity wise.

I agree with your point, but perhaps only when the timeline is short. From Nature:[1]

> Researchers examined the number of known families of marine invertebrates, as well as sea-surface temperatures, over the course of 540 million years of Earth's history. They found that when temperatures were high, so was biodiversity. When temperatures fell, biodiversity also declined.

This happens because global warming causes a marginal increase in tropical areas:

> Tropical ecosystems are known to be Earth's most diverse, and the tropics would be expected to expand during warm eras.

Of course, from a short-term timeline (say 100 years), the rate of species extinction from global warming will surely outpace the rate of species creation, since evolution has no time to act.

[1]: https://www.nature.com/articles/nature.2012.11350

> Of course, from a short-term timeline (say 100 years), the rate of species extinction from global warming will surely outpace the rate of species creation, since evolution has no time to act.

Which is really the only factor that matters here.

A large quantity of things will likely go extinct before being able to adapt or migrate sufficiently to keep up with the changes.

The re-development of biodiversity takes millions of years, and that’s basically irrelevant from the timescale of humanity.

Changing equilibria is enormously stressful for the biosphere and for our "civosphere". Everything in the world would run along more smoothly if things didn't change so much(!).

You could claim that we humans on earth are all equal and reasonable and it shouldn't be so hard to get along.. Except this breaks down in practice as soon as people want to move from where the climate got tougher and into the places where you said the crop yields will only get bigger. It gets ugly. Migration and turmoil.

It seems to me changing equilibria is precisely what allows the world to run more smoothly! Businesses coming and going, migrants moving from static societies to more prosperous ones, scientific revolutions overturning old ones, etc.

I'm not saying that change doesn't cause any local instability, but the world very frequently net improves from change when its long-term benefits outweigh its short-term costs.

It's not clear to me that several million square miles of land suddenly becoming more habitable wouldn't provide a better economic arrangement for the world 100 years from now, even when you net out the costs of people having to migrate to new areas.

You make some great points. You actually have me wanting to fire up some turbines. Another possibly good societal optimization: backyard pooping. Good for the soil, saves on maintaining a sewage system, and the odds of getting sick from it are surprisingly low.

Given long enough to adapt (perhaps a million years? Perhaps two million?) then there would be no negative effects to the current changes. The dangers are entirely to do with the speed of the current change. The increasing acidity of the oceans will, over the next two centuries, lead to a mass extinction in the oceans which could eventually have large effects on the gases that make up our atmosphere -- and here we need to concern ourselves with black swan events, which will remain unlikely, even 200 years from now, but which, if they were to occur, would lead to an extinction so broad that it would threaten human survival.

As pointed above, there is also human survival tail risk to stopping global warming. How are you so certain to know which tail risk is larger, or likelier?

I don't think you read what I wrote. I never mentioned global warming.

If we continue at current rates of fossil fuel use for another 200 years, the acidification of the ocean will start to endanger phytoplankton, which makes much of the oxygen we breathe. The loss of phytoplankton drove the most serious mass extinction in the Earth's history:


The article that started this thread on Hacker News suggested that the death rate goes up 10% in the winter, which gives some sense of what the tail risk is from cold weather. By contrast, the tail risk from the acidification of the oceans is something like the Permian/Triassic mass extinction. You ask "How are you so certain to know which tail risk is larger, or likelier?" We can be certain because one risk is many orders of magnitude worse than the other.

I don't think you read what I wrote. The tail risk I was speaking of was not a winter death rate increasing by 10%, but the risk of us receding into a deeper ice age over the next several centuries.

The extinction event you're referring to was hypothesized by these researchers to have come from volcanic erruptions:[1]

> During the eruptions, huge amounts of carbon dioxide and molten rock burst through the Earth's crust, burning through coal and limestone, and releasing carbon dioxide into the atmosphere. That made oceans and rainwater more acidic, and dissolved more calcium from rocks into the ocean.

So far, so analogous. But does it seem like you might be exaggerating a tad by comparing human fossil fuel usage to this level of carbon release?

> Payne calculated that the eruptions, which lasted upward of a million years, released 13,000 to 43,000 gigatons (1 gigaton equals 1 billion tons) of carbon in the atmosphere. By comparison, scientists estimate we would release an estimated 5,000 gigatons of carbon if we used up all the fossil fuels in the Earth.

AFAIK, we aren't even at 50% usage over the past 150 years. We can also check this theory against long-term carbon PPM charts, which show at various points in earth's history significantly more carbon concentration then either now or even 250 million years ago.[2]

In any event, the researcher admits himself that the tail risk is not directly comparable to the Permian/Triassic mass extinction (though it's still an important consideration):

> Payne said humans may not ultimately release as much carbon dioxide as the Siberian Traps, but we may be doing it at a faster rate. "We won't necessarily end up with a world that looks as bad as it did after the end-Permian extinction, but that event highlights the fact that things can go very, very wrong," Payne said.

In any event, I think you have a point (in fact I think you've made the best point of all of the responses), but you've exaggerated it to make it as if it's the dominant risk factor in the net calculation as to whether global warming is long-term harmful or beneficial. I don't think this is so clear.

Acting as if our current levels of fossil fuel usage is going to lead to a mass extinction comparable to the end of the Permian/Triassic era comes off as alarmist and motivated.

[1] https://news.stanford.edu/news/2010/april/prehistoric-mass-e...

[2] The way to extend this conversation productively would be to estimate the rate at which these volcanic eruptions were dumping CO2 in the air and compare it to the rate at which we are.

I think you might be the type who regards themselves as very intelligent, but who then undermines that intelligence by arguing in circles. I could pick apart what you wrote, but I think you could also pick apart what you wrote, if you were motivated to do so. You simply aren't motivated to do so, which is interesting in its own way. To take one example:

"AFAIK, we aren't even at 50% usage over the past 150 years"

Yes, but the rate keeps increasing, yes? 50% of what's been used has been used since 1990. That's 25% of the total in 30 years. But I suspect you knew this, so it is curious you chose to ignore this.


I propose we deescalate this conversation. I just checked out some of your other writings (demodexio), and it looks pretty interesting (the Soviet Economy series in particular). Still amazed at the talent and perspectives HN attracts.

I wish you and your projects the best.

Thank you for your comments regarding the material about the Soviet Union.

Humans have already lived through several glaciations.

But we weren't even around yet when the current ice age started 4M years ago.

How do you calculate "net effects" when dealing with millions of people suffering in the near term? What does it take to balance that and end up with a net positive?

It's really hard; that's basically my point.

But I think a good starting place is to model the expected effects on various populations of all of these various factors (increased floods, increased crop yields, etc). If the vast majority of these models are tilted overwhelmingly negative or positive, we can somewhat adjust our confidence levels. Of course, we'll never be able to be that confident when the time horizon stretches so long (100+ years) and the effect sizes are so small (e.g., sea levels are expected to rise by a lower amount on average than the existing low-tide to high-tide variance). But..that's also my point: it's not merited to be so extremely confident that the effects of global warming are going to be so negative (or positive) over 100+ years.

People focus extremely hard on the negatives of global warming, don't focus much at all on the positives (my guess is most people living in urban areas aren't even aware there even exist any positives), and focus their debating efforts on the (as far as I can tell) long ago settled question of whether or not the climate warming is happening, or is caused by humans. My guess as to why this happens is that considering whether global warming could be a positive thing for the world conflicts with an anti-market bias that people in urban areas frequently share.

I think this whole question is naive and simplistic. Its unlikely we'll see straightforward trends like "less deaths from cold" (ignoring that such a concept is ill-defined and inconsistent in the literature the author reviewed); climate is a complex system and heat should really be thought of as energy -- not so much ambient temperature -- in this context.

To boot, "excess deaths" is a pretty nebulous topic and once you start analyzing differences between regions using their political borders (comparative politics), you're only making the concept more abstract. Just as an example of what I mean by this: something not analyzed herein was demographic differences between regions. What is the median age of populace in Nigeria vs. Greenland? Just citing this as an example -- my point is really that the variations between a Scandinavian region and equatorial one could really exceed the scope of any topical research.

I'm not sure if you've read TFA, but calling it simplistic is a bit ... simplistic. The question raised is valid: do we suffer more with a colder climate, or a warmer one, and where are the boundaries, and how far does our understanding reach.

Also, there are no answers, just (intellectually challenging) questions.

Not sure what is TFA.

> The question raised is valid: do we suffer more with a colder climate, or a warmer one, and where are the boundaries, and how far does our understanding reach

That was definitely not the question being addressed here. The question was much more specific (which is good, but I still maintain it was not specific enough); it was basically: "will fewer people die of cold?". Which is a simplistic question mainly because: what does it even mean to "die of cold?" The author never defines that but seems to imply that he thinks its "any deaths above the full yaer average level of death during the winter." Meanwhile, he was comparing disparate regions, some of which don't even have winters. Again, I would argue the whole piece revolves around extremely simplistic thinking about a complex issue.

I think the author lacks domain knowledge to draw conclusions about deaths in Sub-Saharan Africa and this article reads as though the author didn't talk to any experts on public health in these regions.

Uganda has seasons - rainy seasons and dry seasons. If you are trying to understand seasonal mortality trends, you should be considering the seasons that exist in that part of the world. I would imagine that monsoons and flooding bring public health risk - from hypothermia to compromised access to clean water to stagnant water for mosquitos to breed.

Discussing the temperature-dependence of African mortality without discussing other known-to-be-seasonal mortality factors is is bewildering to me. Mosquitoes thrive in certain temperatures. Child and maternal health in Africa remains a serious issue and birth rates are seasonal in many part of Africa. This article asked a question with an incredibly complicated set of answers and tried to come up with a one sentence explanation.

I would suggest that the author spend less time analyzing bad data and more time talking to domain experts. Without sufficient domain knowledge, this analysis has no hope of being accurate.

> Why would cold places adapt so hard that they did better than warm places?

It's plausible that many of the adaptations are trade offs. You do better in the cold by not doing as well when it's hot. Then if it gets warmer in the place it's usually cold, your adaptations to the cold are impediments and make things worse.

And the same thing the other way around. In the place where people have adapted to the heat, if it gets even a little bit cold, they're in trouble.

This implies that climate change could still be making everything worse for everyone. You make it warmer for people adapted to the cold and that's bad. You make it warmer for people adapted to the heat and that's still bad, because they're still where they are. Now it's 145 F there instead of 135 F and their adaptations are insufficient.

We built homes in Australia for mostly clement weather, and so when it gets cold or hot, many homes fail to cope for long. If the swings get worse and longer in duration in either direction, we're going to find it really hard to keep houses livable without blasting air conditioning 24/7.

Certainly an interesting read.

Although, it really makes me think of the words of the Big Lebowski: "That's just like, your opinion, man" which I think aligns with his ultimate conclusion.

Ya, I think too often we have a tendency to take a bet on propositions where there simply is no logical conclusion to be had quite yet given the current information.

I wish more author instead of saying, this is where my bet would be, they would just say, ya there's no good information and this whole thing is up in the air, we just don't know and here are the next steps if we wanted to get closer to knowing.

Because otherwise it leads to a weird bias. For some reason, we have the tendency to believe that someone who's done the research would be more likely to be correct in their bet, but inconclusive research doesn't actually make this true. If the research is inconclusive, having done it doesn't help the prediction.

I think that’s unfair to Scott when the entire article is prefaced by “Epistemic status: Extremely confused! Low confidence in all of this”

The rationalist movement is all about being able to accurately forecast the accuracy of your predictions. Saying we shouldn’t discuss low accuracy predictions at all seems odd - by making early/fuzzy predictions (and acknowledging them as such) we may ex find that we are more accurate than we realize.

Ya, this article did an okay job, I was talking more generally, though I still think there is a few places where he's making bets in that article.

> Saying we shouldn’t discuss low accuracy predictions at all seems odd

I don't think we're even talking low accuracy here, low accuracy still implies some accuracy, what I'm seeing here is random or potentially even worse than random prediction. The data points to things that are way to broad and general to reason about the cause.

I think knowing that is valuable, don't get me wrong, but my conclusion would be, don't bet on this, unless you like playing roulette.

Scott Alexander is a very careful quantifier of his bets, he tracks them year over year and always goes back to evaluate them and make sure he's well calibrated.

I take your point, but he is one of a very few people on this planet who would reliably say he just didn't know if that was a more accurate statement than what he said. The whole thing is not up in the air, there is limited but useful information available now, and he's trying to correctly integrate that.

Can he accurately predict the accuracy of his predictions? I think that's an important factor.

That said, you're right, but I was not focused on him, but on the bias that can be produced in other people when reading things like this.

Though to be honest, I even worry that I have this bias as well. Like because I researched something, yet pretty inconclusive, I feel somehow better equipped to bet on it, and yet I have no idea if at that point I'm doing better than random.

I think its ok, I'd start with hypotheses and when I can, I would test them, and in the absense of a spare planet and mammalian species as your test tube, the only thing I can think of as a proxy for the proverbial test tube would be what statistics we can find.

I thought it was well worth the read and he left no uncertainty about the uncertainty of his test results.

He does quantify his degree of belief in his predictions, and he compares to what they would look like if he was perfectly calibrated, see https://slatestarcodex.com/2020/04/08/2019-predictions-calib...

Maybe not the most 100% rigorous analysis that one could do, but certainly well beyond how self-accountable most people are.

> There are only about sixty million deaths per year total, so if this is true then almost 10% of all deaths are due to cold. That sounds…extremely untrue, right?

> Deaths definitely go up every winter, from about 4000 to 4500. So yeah, this is about 10% extra deaths during the cold season.

This second point isn't confirming the first. A ~10% increase in deaths during the cold season isn't enough to attribute ~10% of all deaths to cold, unless the cold season lasts all year.

> But [minimum mortality temperature] is very different in different regions. In Sweden, it’s 18C (64F). In Florida, it’s 27C (81F). The only constant is that it seems to be about 80% of the way through the temperature distribution of a region

> You could argue that this is at least partly because of cultural adaptation. The “effective temperature”, the one that’s reaching your blood vessels and your heart, depends on things like how many layers of clothing you wear, how often you go outside, how much air conditioning you use, et cetera. So for example, in the figure above, Stockholm doesn’t get any increased mortality from the cold, no matter how cold it gets. Plausibly that’s because they’ve organized their lives and built environment around surviving cold winters. One study failed to find any excess cold-weather deaths in Siberians even at temperatures as low as -52C (-62F).

But the chart shows lots of excess cold mortality in Beijing, with its frigid winters. You can't live in Beijing at all without being able to deal with lethally low temperatures. The cultural adaptation story must be partially true, but it has some serious problems.

What a nice illustration of the limitations of pure empiricism.

Is it though? Because it seems like the questions can only be answered with better empirical data. As the author said, the studies of this are unimpressive and the data insufficient.

I am not sure there is an amount of data where these problems truely go away -- too little, this, too much, other issues. I guess I am a "theory-ladenist" https://en.wikipedia.org/wiki/Theory-ladenness

Who isn't, in our post-modern times ?

The author, being an (anti)rationalist, is well aware of these issues : "The map is not the territory." is a popular mantra of theirs.

But I guess that it's much harder to apply in practice...

Do you mean the article's author? He is of the rationalist community.

Temperature station locations in the GHCN ... Notice how most of Africa is blank.


What about biological or habitual adaptation, maybe call it acclimation? People in different climates will have different ways of maintaining homeostasis relative to the weather and technological adaptations they have available for it. If you live your life in high heat environments, your habits and to some degree your body will adapt to keep you cool.

If heart attacks are a significant component, then maybe some of these deaths can be explained by what amounts to shock from one's baseline?

I think the cultural adaptation is severely undervalued here. I grew up in a hot/humid climate and I would be freezing at 25 degrees C . Go to coastal India in the winter if you don't believe me. Conversely I now live in a very cold place and walk around in shorts at 15 and am comfortable with just a sweater all the way to 5 degrees or so.

Naïve post here, I did read the "[Epistemic status: Extremely confused! Low confidence in all of this]", and I'm commenting in the same manner :

Death is (most of the time) not related to temperature itself, but to some bacteria/virus/infections/X, and that's the important point, X varying with the temperature ! Bacterias and viruses are living things too, they have their preferences !

Yeah, many common cold occurs during winter ...! But also, you're most subject to contracting malaraia if you're in a hot/humid weather., because, yeah, that's where malaria lives, not in NY or Tokyo, september to june. Then, which one will kill you ? One ? Both ? Or also the one your immune system is least able to handle ?

I did not dig a lot into the mathematical models here ... But somehow it tickles me ! I'll have a deeper look, and would be very interested if anybody else does the same, share your findings !

Naïve post here, I did read the "[Epistemic status: Extremely confused! Low confidence in all of this]", so I'm commenting in the same manner :

Death is (most of the time) not related to temperature itself, but to some bacteria/virus/infections/X, and that's the important point, X varying with the temperature ! Bacterias and viruses are living things too, they have their preferences !

Yeah, many common cold occurs during winter ...! But also, you're most subject to contracting malaraia if you're in a hot/humid weather., because, yeah, that's where malaria lives, not in NY or Tokyo, september to june. Then, which one will kill you ? One ? Both ? Or also the one your immune system is least able to handle ?

I did not dig a lot into the mathematical models here ... But somehow it tickles me ! I'll have a deeper look, and would be very interested if anybody else does the same, share your findings !

If you're wet and in 54 degree F weather, you can get hypothermia and die after ~6 hours if you can't seek shelter or adequate apparel. People die in the wilderness like this often, as do people without homes. Rain and wind are sufficient killers.

We can all read it how we like it: “Climate researchers ignore undesired effects”, or “contrarian outsider is cherry-picking results”. Intention or not, this serves only as flamebait and it will get us nowhere.

Are you suggesting that the author should censor himself to appease extremists on both sides ?

I would say that on the contrary, this kind of blogpost can be useful to make people that can still change their mind to think about this issue.

The number of people dying of exposure in Russia every years is quite a lot, and you can't call Russians not culturally adapted to cold.

The combination of a high average alcohol consumption rate and cold temperatures in particular is dangerous.

From the article:

> One study failed to find any excess cold-weather deaths in Siberians even at temperatures as low as -52C (-62F).

I used to work with some Russian insurance companies. They had 0 faith in government population data, in particular mortality.

At one point, in the 00’s, they were using late USSR data, which they thought was doctored too, but that was cancelled off by the improvement in health standards.

The Siberians who couldn't figure out how to survive cold weather were killed off by cold centuries ago. If climate change caused sudden cold snaps in normally warmer regions there would likely be many deaths.

The weather you have every day tends to not kill many people. It's surprises that are the real killer.

What interestingly means that warming Siberia may increase the number of people dying due to the cold.

how long does an article like this take to write? Felt very well written!?

That's Scott Alexander. He's an amazing writer - possibly one of the best of the 21st century. All the more amazing that he just posts this stuff for free.

He's getting paid subs from substack now (and they gave him a good first-year deal), but it's mostly people who pay out of goodwill (there are a few sub-only posts and comment boards, but it's 90% free conent).

I would guess it still takes a while, if only to find the relevant information.

Isn't a global warming usually what precedes an ice age? Just saying...

Before commenting, do NOT miss the disclaimer at the top:

"[Epistemic status: Extremely confused! Low confidence in all of this]"

This is Scott having a conversation with his readership, not asserting a Bold New Idea.

Wish this were more common.

This is how knowledge is created: in communities of smart people with access to diverse sets of information — and crucially, with an open-mindedness to whatever conclusion the data points to.

Exactly what I was thinking while reading the article. Particularly at

> I realize it’s awkward to propose two different mechanisms for the general heat/cold-death relationship and the African extreme, but I don’t have any better ideas.

When do you ever read that in a scientific paper? In a podcast by some (self-proclaimed) science communicators, they mention from time to time how the media gets it backwards and that asserting absolute truths is not very scientific, but rather that questioning things and being open minded to whatever the data tells you is how science works. And then you open a paper that, as obscurely worded as possible, describes that given X you get Y. And the next paper claims the opposite. No doubt indicated, just business language stating things as they are.

I dunno, I like blog posts a lot better than trying to get useful info from scientific papers and weighing diverging conclusions based on methods used and other factors. Also, the lack of hyperlinks in papers. It's 2021, people, try clickable words or links in footnotes rather than having to DDG for (and then pay 40 bucks for or sci-hub) the citation mentioned somewhere on page 7 while you were in the middle of a paragraph on page 3 and then still find the relevant part of said citation.

The pdf format is partially to blame for the lack of hyperlinks. Hopefully we'll see more html-first papers in the future.

One of my pet peeves about the internet and modern rhetoric in general is how people are forced to write defensively, for fear of any omissions being construed as something you explicitly said, or a not fully finished thought as a binding contract. There's very little wiggle room to be wrong, and I don't mind being wrong, but you don't really get the chance to be constructively wrong in that format.

I've found a conversational trick in saying "But I haven't finished thinking about this yet.". It can sometimes be a bit of a thought terminating cliche, but I find it stops people jumping to contest obvious details in order to get started proving me wrong. People seem to acknowledge that I know I could be wrong, so they're more helpful in the conversation rather than antagonistic or dismissive.

Global warming is going to increase both cold and heat related deaths, given that it's likely to (and has already started to) produce more extreme temperatures at both ends of the spectrum.

Where can I read that global warming is likely to increase the number of extreme cold events? Is it mentioned by IPCC?

You can Google "does global warming cause extreme cold". Here are my first results:

"This Is Why Global Warming Is Responsible For Freezing Temperatures Across The U.S." (Forbes): https://www.forbes.com/sites/startswithabang/2019/01/30/this...

"Climate change: Arctic warming linked to colder winters" (BBC): https://www.bbc.com/news/science-environment-58425526

"How global warming can cause Europe's harsh winter weather" (DW) https://www.dw.com/en/cold-winter-global-warming-polar-vorte...

"Record cold, intense storms and tornadoes amid global warming: Could there be a connection?" (USA Today): https://www.usatoday.com/story/news/nation/2021/02/17/global...

Seems like selection bias to me. You can also Google "does global warming cause warmer winters" and get:

"How Warming Winters Are Affecting Everything": https://www.npr.org/2020/02/18/803125282/how-warming-winters...

"5 reasons why your warmer winter is so alarming": https://www.edf.org/blog/2020/02/12/5-reasons-why-your-warme...

"Winters are warming faster than summers. These US cities could lose weeks of freezing days by 2050." https://www.vox.com/science-and-health/2018/12/20/18136006/c...

Well, the increased variability itself may be a part of the climate change.

I’ll give an anecdote. I’m working on a project that tracks the length of the rainy season over time in a certain region. There is no clear trend one way or another, but what does stick out as a super strong and clear trend is that the variability of both extremes occurring is increasing.

But the subject at hand isn't whether winters are going to be warmer. The topic was extreme weather events. And the question wasn't "is this indisputable gospel" or something, it was "where can I read about this?" Of course I biased towards selecting the links where you could read about it!

I don't want trash news articles. They establish nothing. Read the first one, it's not good. Want modelling from someone reputable like the IPCC that balances the offsetting forces and quantifies what to expect on net.

"50 percent more extreme cold weather events under RCP8.5"


"This is how a polar vortex works, therefore there will be more cold weather events"

(which is obviously faulty logic since that doesn't account for an increasing mean temp, which is why modelling is needed to balance out these offsetting considerations)



You have to understand, it’s incredibly frustrating to try to have a serious conversation with someone who not only pulls out the intellectually lazy “[citation needed]” trope, but makes no specific demands about what citation is acceptable until after the fact, when they can deem respected news agencies like the BBC or DW as “trash” and demand more citations! Is that Forbes article “trash”? I don’t think so - it’s a clear explainer written for a layperson by someone well-credentialed, and I had no reason to think based on your comment that you were anything but a layperson.

Anyway - the next article, from the BBC, is a report on a study published in Science. The study is linked to in the text, it’s called “Linking Arctic variability and change with extreme winter weather in the United States” if you prefer papers over news articles summarizing them.

I was extremely specific in what I was asking for initially. I asked for evidence that the number of extreme cold events is going to be increased. None of the first two articles grapples with that claim. That's why I called them trash. They're trash in the sense that those sources aren't addressing the claim that I initially asked to see a citation for. They outline a mechanism that will lead to more cold spikes but it doesn't address my question of whether on net we are going to see more cold spikes given the offsetting impact of mean warming.

I reject the accusation that I'm pulling a "citation needed" trope. The citation I shared above, which more directly addresses what I'm asking and is from more reputable bodies than your citations, says the exact opposite thing to what you're claiming and so what I'm doing is not an example of this trope (which is where someone asks for a citation for a well established fact as a rhetorical device).

I suppose it’s debatable, but, rather than being “extremely specific”, I think a common-sense interpretation of “give me sources showing global warming will increase the number of extreme cold events” could be reasonably met with news articles reporting on and explaining papers showing “a mechanism that will lead to more cold spikes” - your words, emphasis mine, because “more” implies a greater number, as requested. And these kinds of articles are widely published, have been for years, and are easy to find. Your comment _reads_ like a demand for easily Google-able common knowledge, even if it wasn’t intended to be. And if it’s not the articles themselves that are “trash”, it’s even more rude and inflammatory to denigrate my effort to provide them to you as “trash”.

Anyway: it’s definitely interesting and surprising that the IPCC’s report states that extreme cold events will decrease, when you’ve got experts and studies and mechanisms claiming otherwise, not to mention non-stop record breaking winters. The IPCC report is 4000 pages long and I’m not qualified (or blessed with the time) to pick through it and reconcile those things. Maybe the IPCC paper doesn’t consider the impact climate change is having on the polar vortex settled enough to factor it in (at least one of the articles above claims it’s still not universally accepted); maybe, as you suggest, the net warming will offset it; maybe, as someone else suggests in that thread, we're operating on different definitions of "extreme"; maybe certain areas will see an increase of extreme cold spikes but on net they’ll go down around the surface of the planet, which depending on where they are still complicates the calculus in the fine article quite a bit - if Texas has increased days or intensity of extreme cold but Antarctica has less, well, there’s a whole lot more people who might die in Houston than at McMurdo Station, even if Antarctica is quite a bit bigger than Texas. I’ll revise my priors and was wrong to state with certainty that extreme cold events will increase given the IPCC report, but after a near-decade of unprecedented winter weather disasters happening annually and a well-established mechanism that explains it, I’m not willing to write the claim off.

I misspoke when I said "more". I meant to say "new" or "novel" in that sentence.

I reacted in such a way because I interpreted your initial response to be a "let me google that for you" flavor of borderline sarcasm, as if the question I was asking had an obvious answer and was clearly settled, when the articles you shared don't answer the question I was asking. My initial read on your sarcastic intention was confirmed when you accused me of repeating a "citations please" trope. So if you're going to take such a sarcastic approach, then I am not going to pretty up my language when you share news articles that do not address the question I'm asking.

  "when you’ve got experts and studies ... claiming otherwise"
Who claims otherwise? I'm still waiting for that. The articles you shared showed that there will be new cold snaps, not that the overall frequency of cold snaps will increase. These are related but very distinct questions, given that mean temperature rise is an offsetting factor that may or may not dwarf the mechanism being described.

  "there’s a whole lot more people who might die in Houston"
These are all fair points that need to be fleshed out. The mere question of whether there will be more cold snaps (however that's measured and defined) doesn't necessarily entail much insofar as deaths from cold goes. But I do want to see that question answered as a starting point.

Yes, hardly anyone reads the whole IPCC report, and the conclusions tend to deform or leave out important parts. I specifically remember the case of methane being an important greenhouse gas having been dropped some IPCC reports ago.

I searched the latest IPCC report with non-expert eyes and it seems to say the opposite: https://news.ycombinator.com/item?id=28963266

That wouldn't be global warming then, given that temperature is measured by averaging over an entire year. If it's both hotter and colder the average wouldn't change.

The prediction for decades has been:

1. Average global temperature increases. 2. Winters get colder on average 3. Summers get hotter on average, more strongly than 2.

Or if you prefer simple arithmetic, the average of -1 and 1 is 0. The average of -2 and 4 is 1. The second one has a colder "winter" but it's still warmer on average.

> 2. Winters get colder on average

I have never heard this. Do you have a reference?

I am no expert, but I looked for any statement about winter temperatures from the latest IPCC report. I found this in TS.2.6:

    > Warming of the land surface during the period 1971–2018
    > contributed about 5% of the increase in the global energy
    > inventory (TS.3.1), nearly twice the estimate in AR5 (high
    > confidence). It is virtually certain that the average
    > surface warming over land will continue to be higher than
    > over the ocean throughout the 21st century. The warming
    > pattern will likely vary seasonally, with northern high
    > latitudes warming more during winter than summer (medium
    > confidence).  {2.3.1, 4.3.1, 4.5.1, Box 7.2, 7.2.2,
    > Cross-Chapter Box 9.1, 11.3, Atlas 11.2}

    > The frequency and intensity of hot extremes (warm days and
    > nights) and the intensity and duration of heatwaves have
    > increased globally and in most regions since 1950, while the
    > frequency and intensity of cold extremes have decreased
    > (virtually certain). There is high confidence that the
    > increases in frequency and severity of hot extremes are due
    > to human-induced climate change. Some recent extreme events
    > would have been extremely unlikely to occur without human
    > influence on the climate system. It is virtually certain
    > that the further changes in hot and cold extremes will
    > occur throughout the 21st century in nearly all inhabited
    > regions, even if global warming is stabilized at 1.5°C
    > (Table TS.2, Figure TS.12a).
This seems to contradict your claim.

Also the most recent National Climate Assessment says this in its summary finding (https://nca2018.globalchange.gov/):

    > Declines in snow and ice cover caused by warmer winter
    > temperatures are expected to negatively impact the winter
    > recreation industry in the Northwest, Northern Great Plains, 
    > and the Northeast.

I think you're right that 2. is misstated, in my rush to ELI5. Thanks for the correction. I meant to refer to "increase in extreme weather events" not decrease in average winter temp. The IPCC seems pretty clear that on average, we are getting less cold temperatures. (And indeed Scott's article is exploring the implications of there being less cold temperature).

I can find references in the latest IPCC report to increased frequency of droughts, heavy rain, and heat waves, but I can't find much mention of extreme cold events; I was under the impression that these were predicted to be increasing too (i.e. more severe winter weather systems with most non-storm winter days being warmer, or put differently increased variance as the mean increases), but maybe that's not correct.

I stand by my main point which was that you _could_ have an increase in both extreme cold events and extreme hot events while the average temperature is increasing, to correct an oversimplification I believe the GP was making. I think this sibling made that point more concisely though: https://news.ycombinator.com/item?id=28961979.

> I can find references in the latest IPCC report to increased frequency of droughts, heavy rain, and heat waves, but I can't find much mention of extreme cold events

I believe my quoted text above states that the frequency and intensity of cold extremes has decreased, as a "virtually certain" fact.

> I stand by my main point which was that you _could_ have an increase in both extreme cold events and extreme hot events while the average temperature is increasing, to correct an oversimplification I believe the GP was making.

Yes, as a mathematical fact this is undoubtedly true.

I think there is a subtlety in the report there - they seem to use “extremes” to refer to something like the 75th %ile bounds, as in “the edges of the normal range”. Whereas “extreme weather events” is a similar phrase for a different thing, they are more like the 99th %ile outliers. (Made up numbers for discussion, not claiming the actual%, just trying to illustrate a distinction).

Note in your quote how they refer to both:

> The frequency and intensity of hot extremes (warm days and nights) and the intensity and duration of heatwaves

And for cold they say:

> while the frequency and intensity of cold extremes have decreased

But no mention of extreme weather events like storms. This might sound pedantic but I think it’s two different meanings of “extreme”, they discuss the differences a bit in https://www.ipcc.ch/srocc/chapter/chapter-6/.

Anyway, low epistemic confidence on this bit, just my read is a bit less certain on that last point than yours.

This is a very important point because it's very commonly believed that extreme cold weather (99 pct) will be worsened, and it's central to Scott Alexander's piece. Not storms per se, just the inverse to heat waves. Can anyone find any evidence for this from primary sources like the IPCC? My guess is the answer is that they're going to reduced. If they're virtually certain that 75th percentile events will be reduced that usually suggests that 99th percentile events will be reduced too.

    average(20, 20, 20, 20)
    => 20

    average(40, 23, 23, 5)
    => 22
As you can see, the average can increase while also having the extremes get worse.

Extra energy in the atmosphere and sea, will lead to more energetic weather - higher highs and lower lows, bigger droughts, heavier intense rainfall events, fewer hurricanes, but the ones that do form will be more powerful, etc. etc.

The term "global warming", while scientifically correct, was dropped for "climate change" to remove this type of confusion, you know the kind - "if the whole world is warming, why did we just have a huge ice storm in Texas?"

Can scientists start giving the warming in approximate extra joules in the atmosphere instead of saying 1°C? It would be a rough measure, but like giving volume as "number of VW beetles" or data as "number of libraries of Congress", a large number of joules is something more easily compared than a single degree C.

They already do, it's just harder to understand for the overwhelming majority of people, so it tends to stay in more specialized sources.

At this point, "global warming" is shorthand for "climate change"

It can be both colder and warmer at different rates, the average would change

That's why its now usually called "climate change" since if you dump more energy into the system that can lead to more evaporation, more moisture in the atmosphere and stronger storms both from the moisture and energy. The greater warming at higher latitudes is also changing the climate in ways that increase both cold and heat waves.

Kind of off topic but seeing the current comments, keep in mind that excess deaths due to temperature is but a tiny fraction of the equation. Co2 levels and its impact on our cognitive capacity, ocean acidification, loss of crops, access to water, massive population migrations, warming of permafrost, &c. are all much more likely to cause problems

> Co2 levels and its impact on our cognitive capacity

This is junk science.

The CO2 level of the open atmosphere is ~400 ppm. The CO2 level aboard a nuclear submarine can range between ~2000-10000 ppm. 10000 ppm is enough to cause sleep disturbances and headaches, and we're less sure about the range between 5000-10000, but we're talking orders of magnitude away before we start seeing issues among people who engage in cognitively challenging work on a daily basis. The CO2 levels aboard the ISS are usually a bit lower--they try to keep it under 5000 ppm--but the astronauts there are even more closely monitored for medical issues and also have to perform cognitively challenging work. These are over extended periods of time between 3-9 months.

If the CO2 concentration of the Earth's atmosphere went up 10x, you'd have much bigger problems than the cognitive effects of CO2 exposure.

You'll notice CO2 levels at 1000 ppm. The air will feel "stuffy," you'll feel lethargic, and feel like going outside. This is the primary reason why meetings at work are so stultifying. There's just too much CO2 in the room for anyone to think clearly. Just carry a CO2 meter around and measure it yourself. Once you're aware of it, the feeling is impossible to miss.

If the CO2 level of the atmosphere doubles, we are still going to have bigger problems to solve.

> Just carry a CO2 meter around and measure it yourself. Once you're aware of it, the feeling is impossible to miss.

Sounds like a combination of confirmation bias and psychosomatic placebo effect to me. Plus you’re assuming a specific correlation between subjective minor discomfort and cognitive performance.

I would posit that the level of CO2 you need to cause detectable society wide problems is probably lower than the level that makes a room actively uncomfortable to be in.

There's a reason why we already have universal colloquial language to describe a room with too much CO2, "stuffy," "getting some fresh air to clear your head." We all know this stuff intuitively, we've experienced it directly our whole lives.

You can posit whatever you like, but I don't see any evidence.

Edit to reply to ninja edit:

> There's a reason why we already have universal colloquial language to describe a room with too much CO2, "stuffy" "getting some fresh air to clear your head." We all know this stuff intuitively, we've experienced it directly our whole lives.

First off, you're going back to the perception of minor discomfort to defend the claim that CO2 levels that aren't even high enough to cause minor discomfort are high enough to cause "detectable society wide problems". This strikes me as incoherent and evasive. Secondly, you're assuming that the minor discomfort of being in a "stuffy" room is entirely caused by CO2 concentration. (In my personal experience, body and food odors are the main sources of discomfort when I'm in a poorly ventilated space.) And thirdly, you're assuming that this discomfort necessarily causes poor cognitive performance.

CO2 will be elevated in a stuffy room, but that's not actually what you're noticing. It's humidity and VOCs.

If CO2 was actually high enough to be a problem, the first symptoms would be an increase in heart rate and rate of respiration. Kinda the opposite of lethargy.

No, it really isn't. Plant conservatories never feel stuffy even though the humidity is high, and the same room with fewer people in it doesn't feel stuffy either.

I am very interested in this because there appear to be studies with conflicting conclusions (e.g., https://ehp.niehs.nih.gov/doi/10.1289/ehp.1510037 says 1,000 ppm causes cognitive decline). This has made me want to run some experiments.

> there appear to be studies with conflicting conclusions

So far, conflicting conclusions are more common throughout much of recent climate science than any of us like. The basic lab bench physics behind CO2 is obviously very well-understood but long-term global climate (as opposed to regional, seasonal weather) is a 'wickedly' hard problem.

Modeling future global climate shifts over years and decades is hard because Earth's climate is a highly-complex, dynamically coupled system with thousands of interacting variables and possible feedbacks. Then extrapolating the output of those models to estimate significant changes to health, agriculture and extreme weather event severity and frequency requires making assumptions which are not nearly as well-understood. Then trying to adapt those estimates to further estimate the relative benefits, costs and impacts of myriad regulatory, economic and behavioral policy proposals is the kind of thing which would cause my favorite stats prof to say "It's fine... that's why god made error bars".

That is a good argument for discontinuing putting more carbon into the atmosphere until we understand it better.

Even doubling would already have an impact. The fact that astronauts can operate a few weeks in extreme conditions doesn't prove anything. I'm not talking about top of the line engineers/scientists working at 70% capacity for a few weeks, I'm talking about long term human scale average decline of cognitive capacity which would get worse over generations

We see no slowing down in the rate of co2 production and according to many studies we might reach 1000ppm or more by the end of the century.

Anyways, I'm not saying each of these are the end of humanity, I'm just saying that "it's going to be 2c more so whatever" isn't the whole picture

> The fact that astronauts can operate a few weeks in extreme conditions doesn't prove anything.

Astronauts stay on the ISS for six months at a time, not “a few weeks”.

What is 6 months on a human evolution scale? Not much

What does evolution have to do with any of this?

CO2 is an input to photosynthesis. How does it lead to a net loss of crops?

EDIT: Of course, with changing climate: some crops will benefit; others will not. But how do we know in net that crop yields will definitely decrease under global warming?

Different plants have different optimum co2 concentrations, more is going to be bad for some, changing weather patterns and water availability will mean upheaval of agriculture for some regions, rising oceans will put some agriculture underwater.

More CO2 is generally good for photosynthesis. Higher temperatures are generally bad for photosynthesis. Which dominates depends on a lot of factors including base temperature, C3 versus C4 photosynthesis, etc. And then there's the changes in rainfall.

Personally I wouldn't be particularly surprised if the first .5 C of global warming was a net benefit for humanity. I'd be pretty surprised if the second was, though, and very very* surprised if the third was. And that's just what takes us to our current target for limiting warming.

More intense weather leads to more crop damage, changes in precipitation patterns and average temperature affect the range and numbers of insect pests, etc.


Bit hard to plant crops during a hurricane, or water them during a drought.

Hurricanes and droughts are regional. Might make growing more expensive and limited in some places, while others are able to grow more.

It's one of many variable, o2 is an input for respiration but if I'm sitting on your chest you'll still struggle. And rest assured, co2 isn't a bottleneck for crops

More extreme temperatures will clearly affect plant growth rates.

I’m guessing among other reasons: droughts, floods, loss of pollinators, extreme temperatures, loss of natural fertilizers, etc.

Astral codex is now the new Freakonomics

Going to choose to interpret this as “seeks counterintuitive results without heed to science”. If this interpretation is wrong, kindly supply clarification and ignore remainder.

Posting level of epistemic certainty makes this not so. This is just a hypothesis and summary post.

But also in a UI question, it appears that people are unable to read content without updating their priors significantly, even with a low proposed information gain multiplier.

This helps understand comments like this.

Could you elaborate? I don't know if you mean "Freakonomics = bad" or "Freakonomics = good", and if so, why?

Does everything have to be good or bad?

No, but it would be good to understand the intentions of the original comment. It feels like the author meant to communicate something but because of how vague it is, it feels like it was worse than having no comment. It makes me think "what am I missing about Freakonomics other than the book I read and the numerous episodes I listened to and enjoyed?"

Precisely. As long as the planet does not overheat, a warmer planet is a better planet.

Except for the fact that most systems on the planet are adapted for the current temperature.

In theory a rising sea level isn't a big deal in the abstract, but we have already built a ton of property along the coast ...

Adaptations change. They will and must. Live is change. I think too many folks on here are too young to remember the very same green doomsday scenarios which we were mentally tormented with and NONE of them panned out. Not buying it. The planet will warm. Faster. Live will go on. The real focus should be on making life multi-planetary asap. That's more important in the long run than anything else.

I think you vastly underestimate the cost of redesigning / rebuilding all of our coastal cities to adapt to the fact that they are now below sea level.

Did you only read the very beginning of the article? Most of the article is skeptical of the idea that there are a lot of deaths caused by cold that would be solved by rising temperatures. (And that's without even getting into that climate change would likely cause more temperature extremes in both directions rather than uniformly increasing the temperature.)

Define "overheat". The crust makes up less than 1% of the planet's mass, so theoretically everything on the surface could burn / boil off and 99% of the planet would still be fine.

It isn't just the amount of heat, but how fast it is being introduced.

Well, let's take a look. In 1978 we were going to be iceball Earth according to the sensationalist media. Let's take a look in 40 years from now and see if it all wasn't just a big scam to scare people into political policies they otherwise would not support.

Since we are commenting on an article that, whatever its other virtues and vices, is extremely well-researched, you might want to take a few minutes to look up the "fact" that you're claiming in your second sentence. The tl;dr is that "The Cooling Earth" was always a minority view among climate scientists; it was actually a competing theory to the anthropogenic global warming theory, as they both started in the 1970s; that one of the theories (global warming) persisted while the other (global cooling) faded quickly can be plausibly explained by both theories offering testable and mutually exclusive predictions, one set of which turned out to roughly match the data and the other of which didn't match it at all. That we are talking about global warming now and stopped talking about global cooling is not a sign of a "scam to scare people," it is a sign of science working the way it is supposed to.

people outside the field are unqualified to parse the data. please go back and get a degree in the field before commenting.

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