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"Arrhenius estimated doubling CO₂ would produce a world 5℃ hotter. This, thankfully, is higher than modern calculations but not too far off, considering he wasn

"Arrhenius estimated doubling CO₂ would produce a world 5℃ hotter. This, thankfully, is higher than modern calculations but not too far off, considering he wasn’t using a sophisticated computer model!" This is talking about the variable called "equilibrium climate sensitivity". Climate sensitivity is a key question in any fact-based discussion of climate change. There are three problems with this statement: 1. ECS calculations based on empirical measurement come in far, far lower than 5 degrees, more like 1.7-2.5 degrees and this has been falling over time, e.g. measurement based estimates of ECS in 2001 were higher than they are today. 2. ECS calculations based on models (which scientists should consider weaker evidence than observational data, but don't) are extremely uncertain, with estimates ranging from 2 to 4 degrees. 3. The range of values models use for ECS are getting wider over time, not narrower as you'd expect. So it's really tough to say that Arrhenius was close given that modern climatologists have no idea what the correct value for ECS is even though they've been studying it intensively for 40 years, that their "sophisticated computer models" disagree very deeply about the right value and this is getting worse with time, and that all those values are still too high when compared to studies that aren't modelling based. It's also worth noting that even the headline is totally misleading. Today climate change is used as a synonym for global warming but for long periods scientists were telling the world that "climate change" meant a new ice age. As late as 1975 (when the switch from cooling to warming was well underway) Newsweek was telling readers that "To scientists, these seemingly disparate incidents represent advance signs of fundamental changes in the world's weather. The central fact is that after three quarters of a century of extraordinarily mild conditions, the Earth's climate seems to be cooling down". http://www.denisdutton.com/newsweek_coolingworld.pdf http://www.denisdutton.com/newsweek_coolingworld.pdf So the article is trying to make it seem like scientists have been talking about global warming for over a century, but that isn't true. We could call it misinformation, perhaps. The physics of CO2 were understood for a long time but there's so much more to the climate than just CO2 that this isn't enough to be able to make accurate predictions.

defrost 4y ago
Congrats on unearthing a 1970s example of O&G disinfomation and propaganda disseminated via the pop media. You assert it represents what scientists of the time were saying, it clearly misrepresents J. Murray Mitchell: > Mitchell was a pioneer in investigation and understanding of climate change, and from the 1960s onwards sought to alert the public to issues of global warming. > In 1976 he described the conjecture of global cooling as irresponsible, and around that time supported other scientists in warning of the damaging effects of increasing CO2 in the atmosphere. [1] https://en.wikipedia.org/wiki/J._Murray_Mitchell https://en.wikipedia.org/wiki/J._Murray_Mitchell Is this a delibrate ploy by yourself, or were you merely ignorant?
- origin_path 4y ago
  The part I quoted isn't about Mitchell, and the article doesn't even quote Mitchell at all. It just reports what one of his studies concludes about temperature trends. I think you've yourself been misled. Mitchell accepted global cooling was really happening and the world was indeed cooling since 1940. See for yourself, here's one of his papers published in 1975: https://link.springer.com/chapter/10.1007/978-94-010-1729-9_12 https://link.springer.com/chapter/10.1007/978-94-010-1729-9_... "In balance, the net thermal impact of all global-scale pollution (including thermal pollution) is likely to be one of warming, perhaps increasingly so after 2000 A.D. It is concluded that the cooling of climate since 1940, apparently still in progress, is a natural phenomenon plausibly related to an enhanced stratospheric loading by volcanic dust in the period" The fact that the world got colder between 1940 and 1975(ish) was never really in dispute up until climatologists realized that they couldn't explain the contradiction between that and the greenhouse gas nature of CO2. At that point they started re-calculating old temperatures to make the cooling trend disappear, and telling people that all the stories published about their agreement in the 60s and 70s were just awful terrible journalists somehow getting what they were saying entirely backwards. To finish it off they claim that anyone who points out that this isn't true is an immoral denier who should be silenced. It's very much 1984 in real life.
  - random314 4y ago
    > In balance, the net thermal impact of all global-scale pollution (including thermal pollution) is likely to be one of warming, perhaps increasingly so after 2000 A.D So Mitchell was right all along! What is this so called "contradiction" that you are talking about?
    - origin_path 4y ago
      The contradiction appears there, in the abstract of his paper. He realized that greenhouse gas physics should trap warmth and CO2 was going up, but accepted that the world had actually been cooling for decades. So how could he explain this contradiction? He presented a hypothesis that maybe it was a volcano-related natural phenomenon, in which cooling caused by volcano exhaust was offsetting the warming effects of CO2, and that over time CO2 would overpower volcano cooling to create rising temperatures. But it was just a guess. The main reason this is important is for the meta-level issue of what claims about consensus really mean. Newsweek didn't really care if the world got colder or warmer, they just wanted to sell papers. Mitchell wasn't misrepresented by the article nor me, as defrost claims. The article doesn't even quote him, it simply cites temperature data from one of his studies as a way to establish what trends existed at the time. Newsweek does so accurately because that's exactly what Mitchell's data did show, as my citation of his paper establishes. By Mitchell's own words, in 1975 the world had not only been cooling for decades but was still cooling! Now defrost might argue that the Newsweek article was deceptive because, in fact, there was at least one scientist who rejected the "ice age doom is imminent" consensus as irresponsible. Indeed, claims about consensus are always very dubious for that exact reason, it's so rarely true. By 1975 there were certainly more than just Mitchell! But a Newsweek reader of the time couldn't have known that. They were being told that scientists in general believed in global cooling. Indeed nobody could deny the world was cooling, as that's clearly what the facts showed, so you'd have been a cooling denier if you'd said otherwise. If anyone had objected by raising Mitchell as a counter-example they'd have been told he was fringe, that his theories were outside the mainstream, that he was delaying action to prepare for the ice age and that even he accepted long term global cooling was real! It can all be very confusing because to learn anything from this, you have to learn to doubt what you "know" is right based on what a handful of people have told you other people believe. Which is hard! But there's an even more confusing meta-level issue. Look at modern graphs of temperature: https://climate.nasa.gov/vital-signs/global-temperature/ https://climate.nasa.gov/vital-signs/global-temperature/ Look at the period between 1940 and 1975. The cooling Mitchell was writing about, that Newsweek, the New York Times, the Washington Post, that so many academics researched and reported on, that governments funded investigations into, that people proposed covering the Arctic with coal dust to fight - it's gone. The graph is flat. According to modern climatologists the cooling trend Mitchell was trying to explain with volcanos never existed at all ... and anyone who says otherwise is a malicious liar.
blkhawk 4y ago
Could you define how long "for long periods" is and who those Scientists were? It is really funny how the "but they told us its cooling" thing is actually only widely known and talked in the English speaking parts of the world (mainly the US). Everywhere else in the world nobody even knows about this argument. There might be a reason for that. Also love you linking to a Newsweek article instead of some relevant papers that detail this cooling trend and how it was predicted. I mean its not a meme at all how popular Media misunderstands science and only reports on the most surprising aspects to get people to buy their publications.
- origin_path 4y ago
  See my comment below for example links to scientific papers talking about the cooling trend. I don't really see why lack of familiarity with the historical facts in some parts of the world should reflect badly on the people who do know them. At any rate, it's not a big surprise. English is the de-facto language of science, the English speaking world has a stronger tradition of free speech and simply has more people who can research obscure topics vs most languages. Also, look at where the global temperature datasets are produced - it's all US and UK universities and agencies. Historical temperature data for much of the 19th and 20th centuries comes primarily from US sources, because for much of the 20th century the rest of the world wasn't running organized weather station networks at all - rest of the world was either dirt poor, being ravaged by world wars or undergoing communist revolutions. The USA has a large scale weather station network dating back to the Victorian era. It also launched lots of weather satellites in the 70s.
orwin 4y ago
What's weird is that climate cooling take. I use to read it a lot and took it as truth, but quite recently i did a research project on a French engineer/scientist, whit basically created the green political movement in the 70s. And i learned that this global cooling is totally false, and never existed at least in my country. So I really thought it was just shills and grifters who managed to fool me for quite some time, but it seems that in the US, this is taken quite seriously. So to be clear: this global cooling 'research' did not exist. We founded research on temperature change in the 60s and on the prior earth climate, adaptation and means of surviving a global cooling, but this was driven by fear of a nuclear winter. All the global cooling 'research' was journalist bullshit at best.

defrost 4y ago

Congrats on unearthing a 1970s example of O&G disinfomation and propaganda disseminated via the pop media. You assert it represents what scientists of the time were saying, it clearly misrepresents J. Murray Mitchell: > Mitchell was a pioneer in investigation and understanding of climate change, and from the 1960s onwards sought to alert the public to issues of global warming. > In 1976 he described the conjecture of global cooling as irresponsible, and around that time supported other scientists in warning of the damaging effects of increasing CO2 in the atmosphere. [1] https://en.wikipedia.org/wiki/J._Murray_Mitchell https://en.wikipedia.org/wiki/J._Murray_Mitchell Is this a delibrate ploy by yourself, or were you merely ignorant?

origin_path 4y ago
The part I quoted isn't about Mitchell, and the article doesn't even quote Mitchell at all. It just reports what one of his studies concludes about temperature trends. I think you've yourself been misled. Mitchell accepted global cooling was really happening and the world was indeed cooling since 1940. See for yourself, here's one of his papers published in 1975: https://link.springer.com/chapter/10.1007/978-94-010-1729-9_12 https://link.springer.com/chapter/10.1007/978-94-010-1729-9_... "In balance, the net thermal impact of all global-scale pollution (including thermal pollution) is likely to be one of warming, perhaps increasingly so after 2000 A.D. It is concluded that the cooling of climate since 1940, apparently still in progress, is a natural phenomenon plausibly related to an enhanced stratospheric loading by volcanic dust in the period" The fact that the world got colder between 1940 and 1975(ish) was never really in dispute up until climatologists realized that they couldn't explain the contradiction between that and the greenhouse gas nature of CO2. At that point they started re-calculating old temperatures to make the cooling trend disappear, and telling people that all the stories published about their agreement in the 60s and 70s were just awful terrible journalists somehow getting what they were saying entirely backwards. To finish it off they claim that anyone who points out that this isn't true is an immoral denier who should be silenced. It's very much 1984 in real life.
- random314 4y ago
  > In balance, the net thermal impact of all global-scale pollution (including thermal pollution) is likely to be one of warming, perhaps increasingly so after 2000 A.D So Mitchell was right all along! What is this so called "contradiction" that you are talking about?
  - origin_path 4y ago
    The contradiction appears there, in the abstract of his paper. He realized that greenhouse gas physics should trap warmth and CO2 was going up, but accepted that the world had actually been cooling for decades. So how could he explain this contradiction? He presented a hypothesis that maybe it was a volcano-related natural phenomenon, in which cooling caused by volcano exhaust was offsetting the warming effects of CO2, and that over time CO2 would overpower volcano cooling to create rising temperatures. But it was just a guess. The main reason this is important is for the meta-level issue of what claims about consensus really mean. Newsweek didn't really care if the world got colder or warmer, they just wanted to sell papers. Mitchell wasn't misrepresented by the article nor me, as defrost claims. The article doesn't even quote him, it simply cites temperature data from one of his studies as a way to establish what trends existed at the time. Newsweek does so accurately because that's exactly what Mitchell's data did show, as my citation of his paper establishes. By Mitchell's own words, in 1975 the world had not only been cooling for decades but was still cooling! Now defrost might argue that the Newsweek article was deceptive because, in fact, there was at least one scientist who rejected the "ice age doom is imminent" consensus as irresponsible. Indeed, claims about consensus are always very dubious for that exact reason, it's so rarely true. By 1975 there were certainly more than just Mitchell! But a Newsweek reader of the time couldn't have known that. They were being told that scientists in general believed in global cooling. Indeed nobody could deny the world was cooling, as that's clearly what the facts showed, so you'd have been a cooling denier if you'd said otherwise. If anyone had objected by raising Mitchell as a counter-example they'd have been told he was fringe, that his theories were outside the mainstream, that he was delaying action to prepare for the ice age and that even he accepted long term global cooling was real! It can all be very confusing because to learn anything from this, you have to learn to doubt what you "know" is right based on what a handful of people have told you other people believe. Which is hard! But there's an even more confusing meta-level issue. Look at modern graphs of temperature: https://climate.nasa.gov/vital-signs/global-temperature/ https://climate.nasa.gov/vital-signs/global-temperature/ Look at the period between 1940 and 1975. The cooling Mitchell was writing about, that Newsweek, the New York Times, the Washington Post, that so many academics researched and reported on, that governments funded investigations into, that people proposed covering the Arctic with coal dust to fight - it's gone. The graph is flat. According to modern climatologists the cooling trend Mitchell was trying to explain with volcanos never existed at all ... and anyone who says otherwise is a malicious liar.

blkhawk 4y ago

Could you define how long "for long periods" is and who those Scientists were? It is really funny how the "but they told us its cooling" thing is actually only widely known and talked in the English speaking parts of the world (mainly the US). Everywhere else in the world nobody even knows about this argument. There might be a reason for that. Also love you linking to a Newsweek article instead of some relevant papers that detail this cooling trend and how it was predicted. I mean its not a meme at all how popular Media misunderstands science and only reports on the most surprising aspects to get people to buy their publications.

origin_path 4y ago
See my comment below for example links to scientific papers talking about the cooling trend. I don't really see why lack of familiarity with the historical facts in some parts of the world should reflect badly on the people who do know them. At any rate, it's not a big surprise. English is the de-facto language of science, the English speaking world has a stronger tradition of free speech and simply has more people who can research obscure topics vs most languages. Also, look at where the global temperature datasets are produced - it's all US and UK universities and agencies. Historical temperature data for much of the 19th and 20th centuries comes primarily from US sources, because for much of the 20th century the rest of the world wasn't running organized weather station networks at all - rest of the world was either dirt poor, being ravaged by world wars or undergoing communist revolutions. The USA has a large scale weather station network dating back to the Victorian era. It also launched lots of weather satellites in the 70s.

orwin 4y ago

What's weird is that climate cooling take. I use to read it a lot and took it as truth, but quite recently i did a research project on a French engineer/scientist, whit basically created the green political movement in the 70s. And i learned that this global cooling is totally false, and never existed at least in my country. So I really thought it was just shills and grifters who managed to fool me for quite some time, but it seems that in the US, this is taken quite seriously. So to be clear: this global cooling 'research' did not exist. We founded research on temperature change in the 60s and on the prior earth climate, adaptation and means of surviving a global cooling, but this was driven by fear of a nuclear winter. All the global cooling 'research' was journalist bullshit at best.