# carbon dioxide and the rice video **URL:** \ **Category:** Factual Questions\ **Created:** [January 27, 2017, 2:39pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313 "2017-01-27T14:39:53Z")\ **Posts on this page:** 14\ **Page:** 2
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [January 27, 2017, 6:40pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/21 "2017-01-27T18:40:28Z")
> [@blood63](#): > > It is not enough for me to show this to my students and say that it is just BS. I need to be able to refute claims stated in the video using the science they learned in class. I’m curious what it is you teach, exactly? ---
**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:** [January 27, 2017, 6:59pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/22 "2017-01-27T18:59:12Z")
> [@wolfpup](#): > > The radiative transfer properties of CO2 are well known and not in dispute. > [@scr4](#): > > CO2 has a major role because it absorbs infrared radiation in wavelength bands where water is transparent. See [this figure](http://eesc.columbia.edu/courses/ees/slides/climate/absorption.gif) (figure 7 from [this article](http://eesc.columbia.edu/courses/ees/climate/lectures/radiation_hays/)). You can see the atmosphere’s infrared absorption is dominated by water, and a big chunk of its “window” is blocked by CO2. So if we close that window by a further 30%, it makes a big difference. Just to add to this for completeness, the first-order approximation for CO2 radiative forcing [is given here](https://en.wikipedia.org/wiki/Radiative_forcing#Forcing_due_to_atmospheric_gas). The approximation says that the net change in radiative forcing to the planet, in watts per square meter, is 5.35 times the natural log of the ratio of any given CO2 level to a reference level. We can sanity check this by computing 5.35 ln(400/285) where 285 ppm is the approximate pre-industrial CO2 level, and we get 1.81 W/m[sup]2[/sup]. This compares very well with the much more precisely calculated and modeled IPCC estimates which have a median value of 1.82 W/m[sup]2[/sup]. It should also be noted that this is net CO2 forcing and doesn’t include other GHGs, nor does it include feedbacks. One of the most important feedbacks is the increase in atmospheric water vapor with rising global average temperature, which acts as a powerful amplifier to the net forcing. So does the darkening of the Arctic surface as less ice and more water (and land) increases sunlight absorption. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [January 27, 2017, 7:00pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/23 "2017-01-27T19:00:29Z")
> [@LSLGuy](#): > > Does the rising CO[sub]2[/sub] level make **Colibri** ’s posts echo? 🙂 They don’t, and _no one knows why_! ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [January 27, 2017, 7:22pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/24 "2017-01-27T19:22:18Z")
> [@Lemur866](#): > > Yes, and back then there were no continental glaciers at all. No Antarctic ice sheet, no Greenland ice sheet. That’s not correct, at least for the Miocene. ---
**Author:** ![blood63](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@blood63](https://boards.straightdope.com/u/blood63)\ **Post date:** [January 27, 2017, 7:41pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/25 "2017-01-27T19:41:49Z")
> [@DCnDC](#): > > I’m curious what it is you teach, exactly? I teach high school science. ---
**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:** [January 27, 2017, 7:58pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/26 "2017-01-27T19:58:04Z")
> [@Quartz](#): > > That’s not correct, at least for the Miocene. No, he’s basically correct in his assertion regardless. The problem is that it’s rather silly to use a word like “only” in a context like “_ **only** _ going back hundreds of thousands of years, perhaps a million years” and then concluding that “… you can’t say that CO2 levels are abnormal.” Because going back that far, you’re dealing with an entirely different ecosystem – you may as well think of it as an alien planet. This is going back to the mid-Pleistocene. Our present ecosystem is not just entirely different, it’s also exquisitely finely balanced and sensitive to disruption, with tremendous inter-dependencies that are only vaguely understood, and with troubling and increasing loss of essential biodiversity, to the point that it’s been credibly speculated that climate change is driving us to an ecological if not climatic tipping point and potentially a sixth mass extinction. The only meaningful measure of relative CO2 levels is the range within which they have varied during the roughly 100ky glaciation cycles of the past million years or so, depending exactly where you want to draw the demarcation point for the beginning of the modern glaciation cycles. This is the earth in which we live, and all the flora and fauna that live with us and on which we intimately depend. And in this era, CO2 levels have varied between a low of about 180 ppm to a high of between 280 and no more than 300 ppm. 400 ppm is unprecedented since the mid-Pleistocene, when nothing even close to humans existed. And further, it’s not going to stop at anywhere near 400 before we can finally get control of it. This is not a small matter. Dredging up ancient tectonic-scale geological history is completely irrelevant to the existential problems we face. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [January 27, 2017, 9:06pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/27 "2017-01-27T21:06:12Z")
> [@blood63](#): > > I teach high school science. Yeah … you tell them kids their futures are messed up _ **BAD** _ … they’re going to be cooking and there’s going to be nothing but death and destruction and they might as well quit school now and enjoy themselves before the burning eternity of HELL falls upon their fates … Just going to be cooking … parboiled … ---
**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:** [January 28, 2017, 6:40am UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/28 "2017-01-28T06:40:41Z")
> [@wolfpup](#): > > … The problem is that it’s rather silly to use a word like “only” in a context like “_ **only** _ going back hundreds of thousands of years, perhaps a million years” and then concluding that “… you can’t say that CO2 levels are abnormal.” Because going back that far, you’re dealing with an entirely different ecosystem – you may as well think of it as an alien planet. This is going back to the mid-Pleistocene. Our present ecosystem is not just entirely different, it’s also exquisitely finely balanced and sensitive to disruption, with tremendous inter-dependencies that are only vaguely understood, and with troubling and increasing loss of essential biodiversity, to the point that it’s been credibly speculated that climate change is driving us to an ecological if not climatic tipping point and potentially a sixth mass extinction… Deniers often use the unexplained and huge climate changes of the past as reason to be unconcerned about present-day changes, but the opposite lesson seems more appropriate. The huge changes in the past show how fragile and potentially unstable climate can be, controlled as it is by some _positive feedback_ loops, e.g. cold –\> ice formation –\> even colder from increased albedo. ---
**Author:** ![Noel\_Prosequi](https://avatars.discourse-cdn.com/v4/letter/n/b19c9b/32.png) [@Noel\_Prosequi](https://boards.straightdope.com/u/Noel_Prosequi)\ **Post date:** [January 28, 2017, 9:36am UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/29 "2017-01-28T09:36:08Z")
An Australian perspective, because Roberts is (for our sins) one of us. I would not encourage the OP to resort to ad hominen attacks in class, but some background might be useful. Roberts is a former coalminer. He has a history of associating with sovereign citizen ideas (Malcolm-Ieuan:Roberts), although he denies current affiliation. He has been a ACG denialists since he saw Gore’s movie. [Wiki here](https://en.wikipedia.org/wiki/Malcolm_Roberts_(politician)). He was elected to the Australian Senate in 2016 with the One Nation Party. This is a fringe political party created essentially by a politician named Pauline Hanson, and it taps into Alt-Right ideas with which Americans will be familiar. She applauds POTUS in his endeavours, etc. Her party was in the wilderness for a long time, but got some seats around the country in the 2016 election, partly on the back of the international rise in right wing discontent that propelled POTUS to office. To put some perspective on Roberts’s views, he went on a political TV show here called Q&A and tried to debate climate change with Professor Brian Cox. [Here](https://www.youtube.com/watch?v=_TTsTYCpKUY) is the debate. Goes for about 20 minutes. [Here](http://www.smh.com.au/entertainment/tv-and-radio/qa-recap-one-nation-senator-malcolm-roberts-embarrassing-clash-with-physicist-brian-cox-20160815-gqt941.html) is a scathing review of Roberts’s performance from the Sydney Morning Herald (serious national newspaper) about it. The review might require some local knowledge to fully understand. Gough Whitlam was a former Prime Minister who had a certain grandeur of style, even while he was a Labor man. Norman Gunston was an early proponent of that style of comedy in which the comedian pretends to be a naif while interviewing the great and powerful, a schtick epitomised in the modern era by Sacha Baron Cohen in his various incarnations. One particualr line from the review I liked was a description of Roberts performing with “all the confidence of a taxi-driver telling Roger Federer what is wrong with his backhand”. ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [January 28, 2017, 10:15am UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/30 "2017-01-28T10:15:45Z")
> [@wolfpup](#): > > No, he’s basically correct in his assertion regardless. The problem is that it’s rather silly to use a word like “only” in a context like “_ **only** _ going back hundreds of thousands of years, perhaps a million years” and then concluding that “… you can’t say that CO2 levels are abnormal.” Because going back that far, you’re dealing with an entirely different ecosystem – you may as well think of it as an alien planet. I disagree. Humans transported that far back would feel very much at home. But the subsidiary point is that the atmosphere changes, regardless of humans. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [January 28, 2017, 11:53am UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/31 "2017-01-28T11:53:57Z")
> [@Quartz](#): > > I disagree. Humans transported that far back would feel very much at home. But the subsidiary point is that the atmosphere changes, regardless of humans. Ah … that’s the big question … yes, the atmosphere changes without human help … but does that also mean humans can’t change the atmosphere … and if they can, then by how much and how quickly? How much and how quickly the climate changes depends entirely how we classify climate … polar deserts have always been polar deserts and always will be … it’s the nature of heat transport, and that’s not changing … ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [January 28, 2017, 4:26pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/32 "2017-01-28T16:26:54Z")
> [@Quartz](#): > > I disagree. Humans transported that far back would feel very much at home. Only if they are accustomed to being chased by sabertoothed cats on their way to work.😉 > [@](#): > > But the subsidiary point is that the atmosphere changes, regardless of humans. We have no record of the global atmosphere changing _as fast_ as it currently is in geological history (possibly excluding an asteroid strike). Even other rapid changes have been orders of magnitude slower than the current one, and they often had catastrophic effects. It’s the unprecedented rapidity of the current changes that’s the problem, since adaptation and migration are too slow to keep up with them. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 28, 2017, 4:57pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/33 "2017-01-28T16:57:40Z")
As I’ve said before, the problem is global warming, not global warmth. If the climate consistently stayed warm for a long period of time, that might well be good. But the rapid transition from what we have now to that is the problem. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [January 28, 2017, 4:59pm UTC](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313/34 "2017-01-28T16:59:11Z")
> [@scr4](#): > > The other fallacy is somehow suggesting that CO2 cannot have a major effect because it’s such a small fraction of the atmosphere. That’s like saying “drink this water, it only has 0.01% cyanide.” Here is something else to point out: if the level of CO[sub]2[/sub] were 0 ppm, the Earth would turn into an ice ball. So while it may be “just” a trace gas, the temperature of the Earth is very sensitive to the ppm of CO[sub]2[/sub] in the air. [Previous page](https://boards.straightdope.com/t/carbon-dioxide-and-the-rice-video/778313.md?page=1)