# Huge risk if global warming passes 1.5C, warns landmark UN report **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [October 8, 2018, 4:38am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641 "2018-10-08T04:38:55Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![Map\_Ylow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/map_ylow/32/85_2.png) [@Map\_Ylow](https://boards.straightdope.com/u/Map_Ylow)\ **Post date:** [October 9, 2018, 4:01am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/21 "2018-10-09T04:01:07Z")
> [@Ethilrist](#): > > Pressing and holding the ALT key modifies every key you press after that. Alt-Home (or the 7 key on your keypad) is the keyboard shortcut to take you to your home page. Chrome is working as expected. How you’re supposed to do an alt-0176, I have no idea. Turn Num Lock on. With it on, that shortcut shouldn’t activate. I just tested this for myself. ---
**Author:** ![Leaper](https://avatars.discourse-cdn.com/v4/letter/l/4bbf92/32.png) [@Leaper](https://boards.straightdope.com/u/Leaper)\ **Post date:** [October 10, 2018, 7:10pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/22 "2018-10-10T19:10:03Z")
Oh, and some say the report is actually conservative in its estimates: [What's Not in the Latest Terrifying IPCC Report? The "Much, Much, Much More Terrifying" New Research on Climate Tipping Points](https://www.commondreams.org/news/2018/10/09/whats-not-latest-terrifying-ipcc-report-much-much-much-more-terrifying-new-research) I think I’m going to tell my nephews not to start families and not to go to college. I need them to know how to use rifles so they can protect me… ---
**Author:** ![Leaper](https://avatars.discourse-cdn.com/v4/letter/l/4bbf92/32.png) [@Leaper](https://boards.straightdope.com/u/Leaper)\ **Post date:** [October 10, 2018, 7:18pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/23 "2018-10-10T19:18:32Z")
N/m; I think this deserves its own thread. Taking to IMHO. ---
**Author:** ![Tim\_R.Mortiss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tim_r.mortiss/32/142_2.png) [@Tim\_R.Mortiss](https://boards.straightdope.com/u/Tim_R.Mortiss)\ **Post date:** [October 10, 2018, 7:20pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/24 "2018-10-10T19:20:10Z")
I remember Al Gore swearing up and down that we only had ten years left before the earth would be uninhabitable - and that was twenty years ago. Twenty years before Al Gore, all the top scientists were predicting an imminent ice age, and we can see how that turned out. I’m not too worried this time, either. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [October 10, 2018, 7:24pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/25 "2018-10-10T19:24:31Z")
> [@Tim\_R.Mortiss](#): > > I remember Al Gore swearing up and down that we only had ten years left before the earth would be uninhabitable - and that was twenty years ago. Twenty years before Al Gore, all the top scientists were predicting an imminent ice age, and we can see how that turned out. > > I’m not too worried this time, either. The “bullshit phase” of this is way behind us. Try to keep up. ---
**Author:** ![Leaper](https://avatars.discourse-cdn.com/v4/letter/l/4bbf92/32.png) [@Leaper](https://boards.straightdope.com/u/Leaper)\ **Post date:** [October 10, 2018, 7:41pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/26 "2018-10-10T19:41:14Z")
> [@septimus](#): > > “Rest _solely?_” _ **Solely?** _ 😕 If we can find another scape-goat no sense behaving ourselves? Not sure how to parse your second sentence, but I was commenting on the seeming general agreement that if the United States government doesn’t get on board, then nothing will be done. If that’s so, then yes, the voting populace of this country has the exclusive power over the fate of human civilization. Where does my logic break down? ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [October 10, 2018, 8:23pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/27 "2018-10-10T20:23:11Z")
> [@Tim\_R.Mortiss](#): > > I remember Al Gore swearing up and down that we only had ten years left before the earth would be uninhabitable - and that was twenty years ago. Twenty years before Al Gore, all the top scientists were predicting an imminent ice age, and we can see how that turned out. > > I’m not too worried this time, either. Your memory is faulty. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [October 10, 2018, 8:24pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/28 "2018-10-10T20:24:51Z")
> [@naita](#): > > Your memory is faulty. Among other faculties. Stranger ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [October 10, 2018, 8:44pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/29 "2018-10-10T20:44:15Z")
> [@Leaper](#): > > I think I’m going to tell my nephews not to start families and not to go to college. I need them to know how to use rifles so they can protect me… Wrong. The Western industrialized countries will survive–they can afford air conditioning–but with a lower standard of living (higher food and energy costs, more extreme weather, migration away from the coasts…). But the human body without air conditioning has limits to how much heat it can withstand so there will be a massive death toll in the Tropics and the poor there will have problems paying for food so more starvation… ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [October 10, 2018, 10:12pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/30 "2018-10-10T22:12:37Z")
> [@PastTense](#): > > Wrong. The Western industrialized countries will survive–they can afford air conditioning–but with a lower standard of living (higher food and energy costs, more extreme weather, migration away from the coasts…). But the human body without air conditioning has limits to how much heat it can withstand so there will be a massive death toll in the Tropics and the poor there will have problems paying for food so more starvation… Although peak temperature levels in the tropics and subtropics, and generally more extreme weather conditions in the summer and winter certainly contribute to both mortality and lower productivity, the bigger issue with climate change is that approximately 40% of the Earth’s population lives within 100 km of coastal areas, and much of it in low- elevation coastal zone (less than 10 m above current mean sea level) which are sensitive to both the impact of general sea level rise and increased incidence of flooding from storm surges and tropical storms. In addition, more extreme weather and overly warm and unpredictably early growing seasons will actually impact crop viability creating food stress unless seasonal variations can be predicted and measures taken to optimize crop yields, and more frequent flooding can damage irrigation systems. The biggest near term impact is food stress, which can lead to political instability, armed conflict, and competition for scarce food and energy resources. Stranger ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [October 11, 2018, 2:52am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/31 "2018-10-11T02:52:50Z")
So what are we looking at? Hundreds of Trillions in property damage and lost economic growth? Millions dead? Millions displaced? ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [October 11, 2018, 3:13am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/32 "2018-10-11T03:13:47Z")
> [@Stranger\_On\_A\_Train](#): > > Although peak temperature levels in the tropics and subtropics, and generally more extreme weather conditions in the summer and winter certainly contribute to both mortality and lower productivity, the bigger issue with climate change is that approximately 40% of the Earth’s population lives within 100 km of coastal areas, and much of it in low- elevation coastal zone (less than 10 m above current mean sea level) which are sensitive to both the impact of general sea level rise and increased incidence of flooding from storm surges and tropical storms. In addition, more extreme weather and overly warm and unpredictably early growing seasons will actually impact crop viability creating food stress unless seasonal variations can be predicted and measures taken to optimize crop yields, and more frequent flooding can damage irrigation systems. The biggest near term impact is food stress, which can lead to political instability, armed conflict, and competition for scarce food and energy resources. > > Stranger This is exactly right. It’s less a question of tropical residents being affected by uncomfortably hot temperatures than a question of hot global temperatures destabilizing the global climate circulation systems. People in tropical regions, particularly Africa, but also Central and South America, are particularly vulnerable to water resource stresses and food shortages from mass crop failures as a result of massive systemic circulation changes. But the compounding factor is that poverty greatly restrains their ability to respond to the challenges. It’s not unreasonable to expect desperate mass northward migration driven by starvation. > [@Wesley\_Clark](#): > > So what are we looking at? > > Hundreds of Trillions in property damage and lost economic growth? Millions dead? Millions displaced? The science is reasonably confident as to general global impacts at any given CO2 stabilization level. The biggest uncertainty is what CO2 stabilization level we will achieve – and that’s a political question, not a scientific one. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [October 11, 2018, 3:15am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/33 "2018-10-11T03:15:18Z")
> [@wolfpup](#): > > The science is reasonably confident as to general global impacts at any given CO2 stabilization level… But where can I find that info? I don’t know if we will get a 2C temperature raise, or if positive feedback will result in a 7-8C temperature raise. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [October 11, 2018, 8:03pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/34 "2018-10-11T20:03:53Z")
> [@Wesley\_Clark](#): > > But where can I find that info? I don’t know if we will get a 2C temperature raise, or if positive feedback will result in a 7-8C temperature raise. You can find that information right in the report that this thread is about, and which I linked, because that’s basically what it’s about, specifically with respect to the impacts of a 1.5°C temperature rise – summarized in Figure SPM.2 in the Summary for Policymakers. Also, in the entirely of the [IPCC Working Group 2 assessment report](http://www.ipcc.ch/report/ar5/wg2/). The amount by which temperature will rise for any given CO2 increase is called climate sensitivity, and the most important metric is equilibrium climate sensitivity (ECS) defined as the rise in equilibrium average global temperature for every doubling of CO2. The exact value of ECS has not been definitively established and indeed it probably changes with different conditions, but it’s virtually certain that it’s between the range 1.5 and 4.5°C, with recent studies suggesting a higher probability that it’s toward the lower end of that. It used to be estimated to have a most probable value of about 3, and now it seems more likely to be around 2°C. It seems pretty much inevitable that CO2 will at least double from pre-industrial levels by the end of the century, so that means a minimum 2°C global temperature rise is probably inevitable, and it may be higher. In the short to medium term (by end of century) that would be the guideline I’d use in looking at impact assessments. I don’t think we’re going to hit 7 or 8°C temperature rise in any reasonably foreseeable future unless we’re totally reckless, and I’m optimistic that we won’t be. If we do, however, it would be utterly catastrophic and would impact all life on earth. Two things we should keep in mind: there is more than enough fossil fuel buried in the earth to reach that level, especially coal, and secondly, if we elevate temperatures to the point that we lose the majority of the polar ice caps, then climate sensitivity becomes greatly amplified and we face runaway climate change. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [October 11, 2018, 8:14pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/35 "2018-10-11T20:14:09Z")
> [@Tim\_R.Mortiss](#): > > I remember Al Gore swearing up and down that we only had ten years left before the earth would be uninhabitable -. I don’t. And I actually did watch the movie. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [October 14, 2018, 2:32am UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/36 "2018-10-14T02:32:29Z")
Here is an argument that this report strongly understates the risk: > [@](#): > > But the report, dire as it is, misses a key point: Self-reinforcing feedbacks and tipping points—the wildcards of the climate system—could cause the climate to destabilize even further. The report also fails to discuss the five percent risk that even existing levels of climate pollution, if continued unchecked, could lead to runaway warming—the so-called “fat tail” risk… > > These cascading feedbacks include the loss of the Arctic’s sea ice, which could disappear entirely in summer in the next 15 years. The ice serves as a shield, reflecting heat back into the atmosphere, but is increasingly being melted into water that absorbs heat instead. Losing the ice would tremendously increase the Arctic’s warming, which is already at least twice the global average rate. This, in turn, would accelerate the collapse of permafrost, releasing its ancient stores of methane, a super climate pollutant 30 times more potent in causing warming than carbon dioxide. > **[Climate report understates threat](https://thebulletin.org/2018/10/climate-report-understates-threat/)** > > Dire as it is, the latest IPCC report largely ignores what may be the most significant climate risk—the risk of self-reinforcing climate feedbacks pushing the planet into chaos beyond human control. So says a team of climate experts, including the... ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [October 16, 2018, 12:55pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/37 "2018-10-16T12:55:30Z")
> [@Map\_Ylow](#): > > Turn Num Lock on. With it on, that shortcut shouldn’t activate. I just tested this for myself. I thank you! **°°°°°°°°°°** — And my degrees thank you. (This and the occasional Ctrl-Alt-Del are the only reasons I ever use that past of the keyboard.) ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [October 16, 2018, 1:27pm UTC](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641/38 "2018-10-16T13:27:18Z")
> [@Tim\_R.Mortiss](#): > > I remember Al Gore swearing up and down that we only had ten years left before the earth would be uninhabitable - and that was twenty years ago. Twenty years before Al Gore, all the top scientists were predicting an imminent ice age, and we can see how that turned out. > > I’m not too worried this time, either. Did you know transcripts of that Documentary can be found on-line? You don’t need special Google-fu: type “transcript Al Gore documentary” if you can’t remember how to spell “Inconvenient.” Google Chrome has a search facility that will show you every instance of “ten” or “10.” There aren’t many and only one is even remotely plausible as a fit: > [@](#): > > And Europe went back into an ice age for another 900 to 1,000 years. And the change from conditions like we have here today to an ice age took place in perhaps as little as 10 years’ time. So that’s a sudden jump. Now, of course that’s not gonna happen again because the glaciers of North America are not there, and… Is there any other big chunk of ice anywhere near there? Oh, yeah. We’ll come back to that one. Hmmm. No; unless you think the Earth was uninhabitable during Europe’s Little Ice Age, that’s not it either. My guess? _ **The Mandela Effect.** _ Or, more likely, you never watched the Al Gore documentary at all but remember sound-bites about it from Sean Hannity or his ilk. [Previous page](https://boards.straightdope.com/t/huge-risk-if-global-warming-passes-1-5c-warns-landmark-un-report/822641.md?page=1)