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This is an old revision of this page, as edited by Enescot (talk | contribs) at 08:29, 30 November 2014 (→‎Mitigation section: new section). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

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References

References

Human-caused: more than half, 110%, or 160%?

I can't find the relevant discussions now, but I know that this has been brought up here fairly recently. AR5 says, "It is extremely likely that human activities caused more than half of the observed increase in GMST," which, while undeniably true, is extremely weak. This mainstream news article tackles the very issue head-on, and cites relevant studies. It turns out that human greenhouse gases are responsible for 160% of the observed rise in surface temperatures 1951 - 2010, but other human factors such as smog result in -50%, leaving a human contribution of 110%, with relatively small error bars. The 10% is probably in the deep ocean waiting for the next major El Nino event to bring it to the surface. The linked article is fairly explicit about Judith Curry's views too, which might be of interest to those on the List of scientists... article. --Nigelj (talk) 19:04, 15 September 2014 (UTC)[reply]

Sounds about right William M. Connolley (talk) 20:40, 15 September 2014 (UTC)[reply]
Let's allow that what we observe is limited to what has already occurred and that many future "tipping points" we can't see yet have already been triggered. We see cities flooding now in Miami, Norfolk, VA and even New York. Sea levels are rising because of the warming increasing the coefficient of expansion of the oceans as well as melting the polar ice caps. The warming is exponential. FEMA and the EPA have been warning us since 1985 that more than 100 East and Gulf coast cities with populations over 100,000 will be flooded 2 feet by 2050 and 4 to 6 feet by 2100. That's supported by the last IPCC report. Already we see methane releases, glaciers the size of Manhattan collapsing, lobsters leaving the Gulf of Maine, die offs of the plankton that produce oxygen that threaten a sixth global extinction event, but what we don't do is connect all the dots so we can see the synergy and the effect of burning carbon. If we stopped burning carbon right now and made carbon dealing a capital offense on account of it being responsible for threatening the lives of billions of people, what we have already done would continue tipping the tipping points, releasing the methane, adding to the species extinctions for another three or four centuries.142.0.102.78 (talk) 02:24, 14 November 2014 (UTC)[reply]
I don't know if I get it. From 1951 to 2010 the observed surface temperatures rose N degrees. So N is 100% of the rise in observed surface temperatures during that period. If human greenhouse gasses caused 160% of N, then they caused 60% more of the rise in observed surface temperatures than were observed, which would be a contradiction, since 160 ≠ 100, unless there was more of a rise in observed surface temperatures than were observed, which means we're not talking about observed surface temperatures after all, but observed plus unobserved potential surface temperatures, right? Now I can see where the greenhouse gasses can be identified as the cause of 100% of the actually observed rise in the surface temperature (N), and that means greenhouse gasses must be the cause of the additional unobserved potential 60% portion of the rise. Then the non-greenhouse-gas(?) human factors of smog etc. subtract 50 percentage points from the unobserved potential greenhouse-gas-caused rise in surface temperatures leaving a net human contribution to the observed plus unobserved potential rise in surface temperatures of 110%. The remaining 10 percentage points of the unobserved potential rise in surface temperatures is probably in the deep ocean, but not hidden due to human causes, meaning that the human contribution to the rise in surface temperatures from 1951 to 2010 is 100% of the observed plus 10% more unobserved potential rise. But since N is a fixed constant equal to 100% of itself, there can be no such thing as 160% of the rise in OBSERVED surface temperatures, right? —Blanchette (talk) 22:35, 16 September 2014 (UTC)[reply]
This discussion reminds me of the expression “giving 110% effort”. All one can give is 100%. Think pie chart - a pie chart showing the maximum percentage is all one color and is 100%. This is fourth grade math.--CSvBibra (talk) 18:33, 17 September 2014 (UTC)[reply]
The cited article says its 100%, but points out that while the man made warming would be 160% of what we see now, its offset to some extent, perhaps as much as 60%, by heat sinks like the ocean and the polar ice that are cooling things down temporarily at the expense of their warming up. As they continue to heat up we loose those checks and balances. That's part of what makes the process exponential, the other part is things like methane releases. Where we are the ones heating things up to the point where methane clathrates melt and release methane which is 25 times as effective a greenhouse gas as CO2 we need to consider that a human caused effect as well.142.0.102.78 (talk) 02:24, 14 November 2014 (UTC)[reply]

I think you mis-read it, N. After quoting the IPCC text you reference, the source says

It’s not just “more than half,” it’s also most likely close to 100%. In fact it’s just as likely that humans are responsible for about 160% of the global surface warming since 1950 as it is that we’re only responsible for 50%.

That's a rhetorical way of saying our text "more than half" is nonsense. Which it is, but we still have to follow the sources, and IPCC said what it said. If there is an agreeable consensus statement to substitute, let's talk about it. Though as you may have noticed I have greatly curtailed my wiki time. As a side note, although I respect those authors immensely, their column in the Guardian is billed as a blog. NewsAndEventsGuy (talk) 00:28, 19 September 2014 (UTC)[reply]

This isn't an argument I'm interested in 'winning' at this stage (as NEAG is quite right about the IPCC text, reliable sources etc), but I do like clarity: It is perfectly possible for a contribution to something to equal more than 100% of the final something. Suppose your bank account balance has risen by $1000 during the past year. There is no reason why I couldn't have given you $1600 during the year (160% of the final increase). Maybe you gave me $500 back at various times. If nothing else was going on, that would have left you with $1100, so maybe you have a standing order for $8.33 a month to someone else set up somewhere? The article also says, "The curve is centered at about 110% – the most likely value for the human contribution to global warming."--Nigelj (talk) 11:47, 29 September 2014 (UTC)[reply]
An excellent point! I think best we'll manage in the lead of this top level article is to retain the IPCC's "most" language. Are you happy with the way the body of the article discusses this? How about at Attribution of global warming? NewsAndEventsGuy (talk) 13:14, 29 September 2014 (UTC)[reply]
My amateur interpretation is that this deals with ranges of uncertainty, taking as a basis for discussion AR5 Chapter 10 pp. 883– 884. "Over the 1951–2010 period, the observed GMST increased by approximately 0.6°C." The best assessment is that forcings from increases in greenhouse gas likely contributed an increase 0.5°C to 1.3°C, other anthropogenic forcings likely contributed –0.6°C to 0.1°C. In December 2013 the same (news)blog authors argued that overall human forcings balanced out at approximately 0.6°C, and the IPCC text supported approximately 100% contribution. In this more recent post, they cite Gavin Schmidt's reading of Figure 10.5 which clearly shows the central estimate of net human caused effect exceeding the measured effect: "Reading off the graph, it is 0.7±0.2ºC (5-95%) with the observed warming 0.65±0.06 (5-95%). The attribution then follows as having a mean of ~110%, with a 5-95% range of 80–130%." In other words, the average estimate of net human caused forcing is around 110% of the measured increase, it's extremely likely that human forcings were in the 80–130% range of the measured amount. Any variation from 100% would then be balanced by natural forcings or internal variability, each of which was estimated at –0.1°C to 0.1°C. From which, the IPCC summary on p. 869 looks rather understated: "It is extremely likely that human activities caused more than half of the observed increase in GMST from 1951 to 2010." . . dave souza, talk 14:07, 29 September 2014 (UTC)[reply]

I think the use of percentages greater than 100% is a mistake. I understand the point being made, but think the usage lacks clarity. If the warming plus cooling from all sources is (say) 4 degrees, and that warming plus cooling from human causes is 3 degrees, then it is clearer to say that 75% of the warming is from human causes. Rick Norwood (talk) 20:06, 30 September 2014 (UTC)[reply]

Do we yet have a suggestion for an article tweak? NewsAndEventsGuy (talk) 20:41, 30 September 2014 (UTC)[reply]

incorrect link

The Scientific discussion section of this article has a link to Scientific opinion on climate change#Statements by dissenting organizations, which does not exist. (Rather, the article exists, but not the section of that article this link points to.) 70.112.237.191 (talk) 02:01, 28 September 2014 (UTC)[reply]

I've updated the link, thanks. Mikenorton (talk) 07:32, 28 September 2014 (UTC)[reply]

Food security deleted

I would like to delete the section on Global warming#Food security. I've previously written a critique of this section [1]. In my opinion, Global warming#Observed and expected effects on social systems already provides an adequate and brief summary on food impacts. There are sub-articles (effects of global warming and climate change and agriculture) that go into more detail. Enescot (talk) 07:42, 31 July 2014 (UTC)[reply]

Comment above reposted from [2]

I've gone ahead and deleted this section. The studies that were referred to are now mentioned in climate change and agriculture#Individual studies. Enescot (talk) 07:51, 29 September 2014 (UTC)[reply]

Neutrality

standard WP:FORUM and wiki and wiki ed bashing, devoid of RS based article improvement ideas contrary to WP:TPG Click 'show' to read anyway

This article says the earth is warming, and yet I keep reading scientific reports that it is not. http://www.express.co.uk/news/nature/518497/Exclusive-interview-with-Dr-Benny-Peiser

Why is Global Warming "settled?" Is Wikipedia setting itself up to be embarrassed, similar to how the Catholic Church preached the sun revolved around the earth and then looked like fools later? Why are wikipedia articles on theories written in such a way to make it seem utterly factual and that any deviance from the "settled science" is an exercise in futility conducted by fools? I think Wikipedia, in general, is on dangerous footing when it presents theories without credible opposition, and does so in a manner that implies dissension as foolish. If a theory is subsequently proven false, it will permanently damage the scientific credibility of Wikipedia. Maybe wisdom and prudence here would be to allow more debate on this theory than make things appear as settled. — Preceding unsigned comment added by 24.97.233.134 (talk) 01:32, 6 October 2014 (UTC)[reply]

I would suggest you read the section above, titled "This article is not NPOV." I don't think anybody is interested in rehashing that stuff. Vanamonde93 (talk) 01:36, 6 October 2014 (UTC)[reply]
I'm not trying to rehash anything (honestly), I just posted a link to an article that just came out. My concern is a philosophical one in general, that scientific articles on Wikipedia seem to take advocacy and agenda driven positions. I'm not countering global warming, I'm not a "denier", I am just a passive reader...a student, if you will, giving objective feedback. Wikipedia says that the earth is "unequivocally warming, and it is extremely likely"..notice the word "unequivocally" to imply basically that anyone who says otherwise is an idiot (forgive for lack of a better term, but that is precisely the implication). Basically, Wikipedia looks to be engaged in activism, in that this is "settled science". But this is an extremely dangerous game Wikipedia is playing. If the earth turns out NOT to be warming, guess who will look like the fool? To me, I see an agenda when I read Wikipedia scientific articles that very often minimize room for dissension, and I wish Wikipedia would not do that. I think articles on scientific theory should always allow rational room for dissension. I wish I could read dispassionate, objective presentations, but instead what I read are activist driven, agenda-driven 'science' with condescending implications against dissension. Dissension is a cornerstone of the advancement of science throughout history. And i see very little room here on WIkipedia for credible dissension. And I believe this is dangerous. I'm sorry if I am rehashing, but this is how I see it, and I am just another web reader. Maybe if you hear a similar complaint "often enough" it might start making a cumulative case, don't you think? — Preceding unsigned comment added by 24.97.233.134 (talk) 01:44, 6 October 2014 (UTC)[reply]
If I sounded like I was making assumptions, I apologize. What I meant was, people who participated in the previous (similar) discussion probably don't want to repeat those arguments. I would still recommend you read that discussion, and I really don't want to get into detail here; in brief, consensus among editors at this point is that covering the "controversy," as it were, would be giving it undue weight. Regards, Vanamonde93 (talk) 01:57, 6 October 2014 (UTC)[reply]
Ahh yes, the tried and true Wikipedia method of silencing opposition...the ole' "Undue Weight" crutch. This is how you do it here on Wikipedia. You first determine, objectively, that your "settled science" has X amount of weight (as if you are qualified to make that to begin with since you are not an objective being) and then you decide empirically that all other possible dissensions are not "worthy" of the greatness of the original theory, hence they cannot be mentioned due to "Undue Weight". Imagine how many scientists throughout history would have never made a single discovery if they allowed a mob of college kids (mostly white males) to deny them rational dissension because of "Undue Weight". There IS valid counter theory to manmade global warming, I'm not saying it's true, but it is valid, whether or not you want to give it "weight", is irrelevant and has no bearing on objective truth. — Preceding unsigned comment added by 50.135.105.151 (talk) 20:53, 22 October 2014 (UTC)[reply]
The claimed "scientific report" linked in the OP's first post is nothing of the kind. It's a shallow, populist grab bag of non-science from all over the place. HiLo48 (talk) 02:44, 6 October 2014 (UTC)[reply]
Agreed. For real scientific reports, read our cited references, and especially see the quoted text from US National Academy of Science.NewsAndEventsGuy (talk) 07:12, 6 October 2014 (UTC)[reply]
As a general rule, tabloids like the Daily Express are not reliable sources for anything, and in particular not for science issues. On the other hand, they thrive on fights, real or imagined. Benny Peiser is an anthropologist, not a climate scientist. Organisations that like to claim "unsettled science" or want headlines like to claim promote such people as "experts" when really their expertise is in other fields (if anywhere). Take a look at Peiser's publications (many of which are only edited, or published in low-quality pseudo-journals like Energy & Environment, which he also co-edited). How much do you find there that pertains to the physical processes of climate change? On the other hand, the IPCC, the US National Academy of Sciences, and even the Royal Society have put real and extensive expertise to the topic, and have published clear and highly regarded positions that show that yes, global warming is definitely happening, and much of it is anthropogenic with a degree of certainty that "withholding provisional consent would be perverse" (to use Stephen J. Gould's definition of "scientific fact"). Wikipedia dispassionately follows the expert opinion on scientific topics. --Stephan Schulz (talk) 08:18, 6 October 2014 (UTC)[reply]

I have to agree that the responses to arguments and FAQs are more those of an advocate than an independent arbiter. As a control engineer I would view the increases leading up to the turn of the century as two lagged step responses, rather than the start of the exponential runaway heralded by the IPCC. Time series analysis would certainly not indicate that the following plateau would follow the escalating atmospheric content of carbon dioxide. Phrases such as "hottest decade in history" are emotionally biased, while not actually claiming the a further increase will occur. The significant point of the whole argument is not whether human activity has caused a change, but whether continuing the activity will exacerbate such change. It is incontrovertible that fuel emissions have caused the atmospheric increase in CO2, the tonnage burned accounting for around double the increase. Two points are debatable. The first is whether the increase can in fact be stemmed, when developing nations are escalating their burning much faster than be compensated for by economic sacrifice in the rest. The second, more important, is the extent to which further CO2 increases will actually cause warming. In contrast to the early activist propaganda that a 'layer' of CO2 was 'reflecting' radiation back to the surface, it is becoming realised that the effect is entirely due to the 'colouring' of the atmosphere. This means that while some radiation can pass directly to space, wavelengths in the 'coloured bands' can only reach space from higher altitudes, where temperatures are much lower due to the thermodynamic lapse rate. Heat must travel to those altitudes by convection or by diffusion, being repeatedly absorbed and reradiated. Radiation spectra exist from as early as 1970. In the ensuing years many such spectra have been measured but do not seem to have been published. By correlating these spectra against the substantial increase in atmospheric carbon dioxide over the ensuing years an objective assessment could be made, independent of speculation and modelling. 58.178.51.244 (talk) 23:30, 18 October 2014 (UTC)[reply]

Please concisely restate any RS-based article improvement suggestions contained in this thread. NewsAndEventsGuy (talk) 00:35, 19 October 2014 (UTC)[reply]

It will be very bad for Wikipedia (but not for me, I will relish the day actually), and highly embarrassing for Wikipedia and it's authors when Science ultimately trumps political dogma. I firmly believe there is a strong political motive to "imposing" man made global warming as "settled science" by a lot of the young, mostly white male authors on Wikipedia (who are left leaning, by the way). Unfortunately, science cares not for the subjective whims of human beings, even if there are a lot of them that share the same political motive. Eventually, Wikipedia will look foolish because it did not allow deviance and presented theory as if it was factual, violating one of the fundamental principles of sound science: debate. — Preceding unsigned comment added by 50.135.105.151 (talk) 20:43, 22 October 2014 (UTC)[reply]
There is no need for "debate" when scientific facts scream at you and show you what is true and what is now. There is no need to "debate" with teenagers reading articles in Daily Mail and using one of many silly arguments "proving" that global warming isn't real based on their lack of understanding of basic scientific data. We don't need debate with people who still think that the Earth is flat, nor do wee need to debate with people who deny holocaust or the Moon landing. If there is a reliable, undeniable source of information that would question global warming, it will definitely appear in this article. Until then, fringe theories and manipulated arguments will not be accepted. Wikipedia will not be bullied by some stupid arguments (you will be embarassed!!1) to include nonsensical theories backed up by conspiracy theory blogs and tabloids. BeŻet (talk) 16:09, 17 November 2014 (UTC)[reply]

Policy section

There's some introductory text in global warming#Proposed policy responses to global warming that I think should be revised:

[...] These competing views weigh the benefits of limiting emissions of greenhouse gases against the costs. In general, it seems likely that climate change will impose greater damages and risks in poorer regions

The text on weighing the costs and benefits of policies is biased. The UNFCCC does not define the problem of climate change in terms of cost-benefit analysis, and economics is not the only way of interpreting this issue [3]. The second sentence is unnecessary because the distribution of impacts is already covered in global warming#Observed and expected environmental effects and global warming#Observed and expected effects on social systems.

Enescot (talk) 05:52, 6 October 2014 (UTC)[reply]

Thanks for paying attention, E. Agree 2nd sentence should get the axe. The first sentence is subject to more than one interpretation. If you read with the assumption that "benefits" and "costs" is necessarily about economics (especially in a monetary sense) then of course I agree with you. It is equally valid to read those words to include intangibles like "Justice, equity and responsibility" (quoted from TOC of link you posted). How would you suggest fixing the first sentence's ambiguity? NewsAndEventsGuy (talk) 06:58, 6 October 2014 (UTC)[reply]
In my view, it would be better to simply delete the entire paragraph, i.e.,:
There are different views over what the appropriate policy response to climate change should be.[1] These competing views weigh the benefits of limiting emissions of greenhouse gases against the costs. In general, it seems likely that climate change will impose greater damages and risks in poorer regions.[2]
Global warming#Discourse about global warming covers these issues, and I don't see why they need to be discussed here as well. Enescot (talk) 07:44, 15 October 2014 (UTC)[reply]
Now I'm confused about what you suggest keeping/deleting. How about replacing this comment and your prior comment with a restatement, using strikeout so we stay in synch? NewsAndEventsGuy (talk) 09:29, 15 October 2014 (UTC)[reply]
I want to remove this paragraph:
There are different views over what the appropriate policy response to climate change should be.[3] These competing views weigh the benefits of limiting emissions of greenhouse gases against the costs. In general, it seems likely that climate change will impose greater damages and risks in poorer regions.[4]
Enescot (talk) 07:02, 24 October 2014 (UTC)[reply]
(A) Thanks for the handholding until I "got it"
(B) I agree to delete that; it does very little for us here
(C) Ccan you point to where we are currently elaborating on the equities mentioned in the first sentence and RS?
(D) Besides deleting that text, I also propose to change the section heading. Mitigation/Adaptation are described in an AR4 SYNTH highlighted bullet item as "options" rather than "policy options". The broader term "policy options" includes things like rate of deployment, who does what when, who pays, and how the equitities are balanced. That's important stuff, but I think the goal of this section is to report on the tools available in the toolbox, which stops short of decisions on what to build ("policy") with those tools. NewsAndEventsGuy (talk) 12:06, 24 October 2014 (UTC)[reply]
(C), global warming#Discourse about global warming does mention fairness and equity issues as agreed internationally by parties to the UNFCCC. The section should be revised and updated some time.
(D) I agree with your suggested change.
Enescot (talk) 07:47, 1 November 2014 (UTC)[reply]

National Security

The Pentagon made a statement that global warming poses immediate risk to US national security. --76.175.67.121 (talk) 16:32, 14 October 2014 (UTC)[reply]

Semi-protected edit request on 19 November 2014

This sentence: "Without the Earth's atmosphere, the temperature across almost the entire surface of the Earth would be below freezing." under greenhouse gasses is not supported by the citation, or the citations of the citation. All citations say is that the average temperature of earth would be below freezing. It could be true that the nearly the entire surface of the Earth would be below freezing, but that's not supported by the citations. Therefore to accurately reflect the citation the sentence should read something like: "Without the Earth's atmosphere, the Earth's average temperature would be well below the freezing temperature of water."[5][6] Also, the citation would be better off using the sources of the national geographic article instead of the article itself. I included them as references for my proposed change.


Cicero agricola (talk) 05:19, 19 November 2014 (UTC)[reply]

Done Stickee (talk) 00:25, 22 November 2014 (UTC)[reply]

Mitigation section

I think that Global warming#Mitigation should be revised. In my opinion, the mitigation section is fairly good at present, but I think that there is some unnecessary overlap with Global warming#Political discussion. The mitigation section discusses low GHG stabilization targets, while the politics section discusses limiting global warming to 2 degrees C. I think that these two topics are similar should be collated in one section. Enescot (talk) 08:29, 30 November 2014 (UTC)[reply]

  1. ^ Banuri, et al., Chapter 3: Equity and Social Considerations, Section 3.1.2: Concepts of equity, p. 85 et seq. in IPCC SAR WG3 1996.
  2. ^ Banuri, et al., Chapter 3: Equity and Social Considerations, Section ??, p. 83, in IPCC SAR WG3 1996.
  3. ^ Banuri, et al., Chapter 3: Equity and Social Considerations, Section 3.1.2: Concepts of equity, p. 85 et seq. in IPCC SAR WG3 1996.
  4. ^ Banuri, et al., Chapter 3: Equity and Social Considerations, Section ??, p. 83, in IPCC SAR WG3 1996.
  5. ^ http://oceanservice.noaa.gov/education/pd/climate/factsheets/whatgreenhouse.pdf
  6. ^ http://earthobservatory.nasa.gov/Features/GlobalWarming/page2.php