Talk:Climate change
![]() | This article and its editors are subject to Wikipedia general sanctions. See the description of the sanctions. |
This is the talk page for discussing improvements to the Climate change article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google (books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
![]() | Climate change is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Wikipedia community. Even so, if you can update or improve it, please do so. | |||||||||||||||
![]() | This article appeared on Wikipedia's Main Page as Today's featured article on June 21, 2006. | |||||||||||||||
| ||||||||||||||||
Current status: Featured article |
![]() | This article is of interest to the following WikiProjects: | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.
Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.
Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.
Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.
|
![]() | This article has been mentioned by multiple media organizations:
|
![]() | This page is not a forum for general discussion about Climate change. Any such comments may be removed or refactored. Please limit discussion to improvement of this article. You may wish to ask factual questions about Climate change at the Reference desk. |
![]() | Discussions on this page often lead to previous arguments being restated. Please read recent comments, look in the archives, and review the FAQ before commenting. |
Frequently asked questions
Q1: Is there really a scientific consensus on climate change?
A1: Yes. The IPCC findings of recent warming as a result of human influence are explicitly recognized as the "consensus" scientific view by the science academies of all the major industrialized countries. No scientific body of national or international standing presently rejects the basic findings of human influence on recent climate. This scientific consensus is supported by over 99% of publishing climate scientists.[1]
Q2: How can we say climate change is real when it's been so cold in such-and-such a place?
A2: This is why it is termed "global warming", not "(such-and-such a place) warming". Even then, what rises is the average temperature over time – that is, the temperature will fluctuate up and down within the overall rising trend. To give an idea of the relevant time scales, the standard averaging period specified by the World Meteorological Organisation (WMO) is 30 years. Accordingly, the WMO defines climate change as "a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer)."[2] Q3: Can't the increase of CO2 be from natural sources, like volcanoes or the oceans?
A3: While these claims are popular among global warming skeptics,[3][4] including academically trained ones,[5][6] they are incorrect. This is known from any of several perspectives:
Q4: I think the article is missing some things, or has some things wrong. Can I change it?
A4: Yes. Keep in mind that your points need to be based on documented evidence from the peer-reviewed literature, or other information that meets standards of verifiability, reliability, and no original research. If you do not have such evidence, more experienced editors may be able to help you find it (or confirm that such evidence does not exist). You are welcome to make such queries on the article's talk page but please keep in mind that the talk page is for discussing improvements to the article, not discussing the topic. There are many forums that welcome general discussions of global warming, but the article talk page is not such a forum. Q5: Why haven't the graphs been updated?
A5: Two reasons:
Q6: Isn't climate change "just a theory"?
A6: People who say this are abusing the word "theory" by conflating its common meaning with its scientific meaning.
In common usage, "theory" can mean a hunch or guess, but a scientific theory, roughly speaking, means a coherent set of explanations that is compatible with observations and that allows predictions to be made. That the temperature is rising is an observation. An explanation for this (also known as a hypothesis) is that the warming is primarily driven by greenhouse gases (such as CO2 and methane) released into the atmosphere by human activity. Scientific models have been built that predict the rise in temperature and these predictions have matched observations. When scientists gain confidence in a hypothesis because it matches observation and has survived intense scrutiny, the hypothesis may be called a "theory". Strictly speaking, scientific theories are never proven, but the degree of confidence in a theory can be discussed. The scientific models now suggest that it is "extremely likely" (>95%) to "virtually certain" (>99%) that the increases in temperature have been caused by human activity as discussed in the IPCC Fifth Assessment Report. Global warming via greenhouse gases by human activity is a theory (in the scientific sense), but it is most definitely not just a hunch or guess. Q7: Does methane cause more warming than CO2?
A7: It's true that methane is more potent molecule for molecule. But there's far less of it in the atmosphere, so the total effect is smaller. The atmospheric lifetime of methane (about 10 years) is a lot shorter than that of CO2 (hundreds to thousands of years), so when methane emissions are reduced the concentration in the atmosphere soon falls, whereas CO2 accumulates in the atmosphere over long periods. For details see the greenhouse gas and global warming potential articles.
Q8: How can you say there's a consensus when lists of "skeptical scientists" have been compiled?
A8: Consensus is not the same as unanimity, the latter of which is impractical for large groups. Over 99% of publishing climate scientists agree on anthropogenic climate change.[1] This is an extremely high percentage well past any reasonable threshold for consensus. Any list of "skeptical scientists" would be dwarfed by a comparably compiled list of scientists accepting anthropogenic climate change. Q9: Did climate change end in 1998?
A9: One of the strongest El Niño events in the instrumental record occurred during late 1997 through 1998, causing a spike in global temperature for 1998. Through the mid-late 2000s this abnormally warm year could be chosen as the starting point for comparisons with later years in order to produce a cooling trend; choosing any other year in the 20th century produced a warming trend. This no longer holds since the mean global temperatures in 2005, 2010, 2014, 2015 and 2016 have all been warmer than 1998.[12]
More importantly, scientists do not define a "trend" by looking at the difference between two given years. Instead they use methods such as linear regression that take into account all the values in a series of data. The World Meteorological Organisation specifies 30 years as the standard averaging period for climate statistics so that year-to-year fluctuations are averaged out;[2] thus, 10 years isn't long enough to detect a climate trend. Q10: Wasn't Greenland much warmer during the period of Norse settlement?
A10: Some people assume this because of the island's name. In fact the Saga of Erik the Red tells us Erik named the new colony Greenland because "men will desire much the more to go there if the land has a good name."[13] Advertising hype was alive and well in 985 AD.
While much of Greenland was and remains under a large ice sheet, the areas of Greenland that were settled by the Norse were coastal areas with fjords that, to this day, remain quite green. You can see the following images for reference:
Q11: Are the IPCC reports prepared by biased UN scientists?
A11: The IPCC reports are not produced by "UN scientists". The IPCC does not employ the scientists who generate the reports, and it has no control over them. The scientists are internationally recognized experts, most with a long history of successful research in the field. They are employed by various organizations including scientific research institutes, agencies like NASA and NOAA, and universities. They receive no extra pay for their participation in the IPCC process, which is considered a normal part of their academic duties. Q12: Hasn't global sea ice increased over the last 30 years?
A12: Measurements show that it has not.[14] Claims that global sea ice amounts have stayed the same or increased are a result of cherry picking two data points to compare, while ignoring the real (strongly statistically significant) downward trend in measurements of global sea ice amounts.
Arctic sea ice cover is declining strongly; Antarctic sea ice cover has had some much smaller increases, though it may or may not be thinning, and the Southern Ocean is warming. The net global ice-cover trend is clearly downwards. Q13: Weren't scientists telling us in the 1970s that the Earth was cooling instead of warming?
A13: They weren't – see the article on global cooling. An article in the Bulletin of the American Meteorological Society has reviewed the scientific literature at that time and found that even during the 1970s the prevailing scientific concern was over warming.[15] The common misperception that cooling was the main concern during the 1970s arose from a few studies that were sensationalized in the popular press, such as a short nine-paragraph article that appeared in Newsweek in 1975.[16] (Newsweek eventually apologized for having misrepresented the state of the science in the 1970s.)[17] The author of that article has repudiated the idea that it should be used to deny global warming.[18] Q14: Doesn't water vapour cause 98% of the greenhouse effect?
A14: Water vapour is indeed a major greenhouse gas, contributing about 36% to 70% (not 98%) of the total greenhouse effect. But water vapour has a very short atmospheric lifetime (about 10 days), compared with decades to centuries for greenhouse gases like CO2 or nitrous oxide. As a result it is very nearly in a dynamic equilibrium in the atmosphere, which globally maintains a nearly constant relative humidity. In simpler terms, any excess water vapour is removed by rainfall, and any deficit of water vapour is replenished by evaporation from the Earth's surface, which literally has oceans of water. Thus water vapour cannot act as a driver of climate change.
Rising temperatures caused by the long-lived greenhouse gases will however allow the atmosphere to hold more vapour. This will lead to an increase in the absolute amount of water vapour in the atmosphere. Since water vapour is itself a greenhouse gas, this is an example of a positive feedback. Thus, whereas water vapour is not a driver of climate change, it amplifies existing trends. Q15: Is the fact that other solar system bodies are warming evidence for a common cause (i.e. the sun)?
A15: While some solar system bodies show evidence of local or global climate change, there is no evidence for a common cause of warming.
Q16: Do scientists support climate change just to get more money?
A16: No,
Q17: Doesn't the climate vary even without human activity?
A17: It does, but the fact that natural variation occurs does not mean that human-induced change cannot also occur. Climate scientists have extensively studied natural causes of climate change (such as orbital changes, volcanism, and solar variation) and have ruled them out as an explanation for the current temperature increase. Human activity is the cause at the 95 to 99 percent confidence level (see the IPCC Fifth Assessment Report for details). The high level of certainty in this is important to keep in mind to spot mention of natural variation functioning as a distraction. Q18: Should we include the view that climate change will lead to planetary doom or catastrophe?
A18: This page is about the science of climate change. It doesn't talk about planetary doom or catastrophe. For a technical explanation, see catastrophic climate change, and for paleoclimatic examples see PETM and great dying. Q19: Is an increase in global temperature of, say, 3 degrees Celsius (5.4 degrees Fahrenheit) important?
A19: Though it may not sound like much, a global temperature rise of 3 degrees Celsius (5.4 degrees Fahrenheit) is huge in climate terms. For example, the sea level rise it would produce would flood coastal cities around the world, which include most large cities.
Q20: Why are certain proposals to change the article discarded, deleted, or ignored? Who is/was Scibaby?
A20: Scibaby is/was a long term abusive sock-master (or coordinated group of sock masters) who has created 1,027 confirmed sock puppets, another 167 suspected socks, and probably many untagged or unrecognized ones. This page lists some recent creations. His modus operandi has changed over time, but includes proposing reasonably worded additions on the talk page that only on close examination turn out to be irrelevant, misinterpreted, or give undue weight to certain aspects. Scibaby is banned, and Scibaby socks are blocked as soon as they are identified. Some editors silently revert his additions, per WP:DENY, while others still assume good faith even for likely socks and engage them. Q21: What about this really interesting recent peer-reviewed paper I read or read about, that says...?
A21: There are hundreds of peer-reviewed papers published every month in respected scientific journals such as Geophysical Research Letters, the Journal of Climate, and others. We can't include all of them, but the article does include references to individual papers where there is consensus that they best represent the state of the relevant science. This is in accordance with the "due weight" principle (WP:WEIGHT) of the Neutral point of view policy and the "Wikipedia is not an indiscriminate collection of information" principle (WP:IINFO) of the What Wikipedia is not policy. Q22: Why does the article define "climate change" as a recent phenomenon? Hasn't the planet warmed and cooled before?
A22: Yes, the planet has warmed and cooled before. However, the term "climate change" without further qualification is widely understood to refer to the recent episode and often explicitly connected with the greenhouse effect. Per WP:COMMONNAME, we use the term in this most common meaning. The article Climate variability and change deals with the more general concept. Q23: Did the CERN CLOUD experiment prove that climate change is caused not by human activity but by cosmic rays?
A23: No. For cosmic rays to be causing global warming, all of the following would have to be true, whereas only the italicized one was tested in the 2011 experiment:[28]
Q24: I read that something can't fix climate change. Is this true?
A24: Yes, this is true for all plausible single things including: "electric cars", "planting trees", "low-carbon technology", "renewable energy", "Australia", "capitalism", "the doom & gloom approach", "a Ph.D. in thermodynamics". Note that it is problematic to use the word "fix" regarding climate change, as returning the climate to its pre-industrial state currently appears to be feasible only over a timeframe of thousands of years. Current efforts are instead aimed at mitigating (meaning limiting) climate change. Mitigation is strived for through the combination of many different things. See Climate change mitigation for details. References
|
Index 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 51, 52, 53, 54, 55, 56, 57, 58, 59, 60 61, 62, 63, 64, 65, 66, 67, 68, 69, 70 71, 72, 73, 74, 75, 76, 77, 78, 79, 80 81, 82, 83, 84, 85, 86, 87, 88, 89, 90 91, 92, 93, 94, 95, 96 |
This page has archives. Sections older than 21 days may be automatically archived by Lowercase sigmabot III when more than 4 sections are present. |
Better response?
I have been wondering if we need a better response for these "I have found a flea/factoid/report that overturns 10,000 elephants worth scientific work". It would be easy enough to add something to the FAQ. Of course, these anonymous posters are not known to check the FAQ, but perhaps we could get some kind of snazzy image template (like Looks like a duck to me) that catches attention and redirects to a specific FAQ question. - J. Johnson (JJ) (talk) 21:06, 9 May 2011 (UTC)
- May I suggest you put that duck on the whole article because [censored] because I'm sceptical88.104.197.108 (talk) 12:46, 2 June 2011 (UTC)
- I agree. It's a common meme that needs it's own FAQ. I dunno about the duck. FAQs are good. They say: Sorry you missed it, but we've already heard that so many times here that we wrote a standard answer to it ages ago. --Nigelj (talk) 21:33, 9 May 2011 (UTC)
- You could uncollapse the FAQ to make it more visible. Right now the code is {{FAQ|quickedit=no}}. Change it to {{FAQ|quickedit=no|collapsed=no}} to make it uncollapsed. On a different note, I don't think the FAQ is effective, because anons could easily disagree with it as out-of-date/inaccurate/ect. Perhaps the solution is to create a message holding a proposal to a higher standard. For example, require anons to "provide the original journal article" when a "study" is cited, which should cut-down on blogs and news sources. 174.52.224.148 (talk) 00:55, 10 May 2011 (UTC)
- Hmm, goes beyond what I suggested, but I like it. Though would need some working out. If anyone is interested, perhaps this should go into its own section. - J. Johnson (JJ) (talk) 22:36, 11 May 2011 (UTC)
- You could uncollapse the FAQ to make it more visible. Right now the code is {{FAQ|quickedit=no}}. Change it to {{FAQ|quickedit=no|collapsed=no}} to make it uncollapsed. On a different note, I don't think the FAQ is effective, because anons could easily disagree with it as out-of-date/inaccurate/ect. Perhaps the solution is to create a message holding a proposal to a higher standard. For example, require anons to "provide the original journal article" when a "study" is cited, which should cut-down on blogs and news sources. 174.52.224.148 (talk) 00:55, 10 May 2011 (UTC)
It is the goal of Wikipedia to provide information to people who want information, not to change the minds of people who have already made up their mind. As long as we keep this article honest, we've done the best we can. Global warming "skeptics" are not going to change their minds no matter what evidence anyone provides. Remember the Bill Cosby record "What train?" Rick Norwood (talk) 11:47, 10 May 2011 (UTC)
- Rick, I think you misunderstood my intent. I am not proposing anything to change anyone's mind, I was suggesting, first, that if this particular "meme" is adequately addressed in the FAQ then we wouldn't have to keep readdressing it here, on the talk page. And second, with that in place, then for all the yahoos that breeze right past the FAQ (visible, or not) we can just give them a templated response. - J. Johnson (JJ) (talk) 22:36, 11 May 2011 (UTC)
- The goal of Wikipedia is to make a good encyclopedia rather than change people's views, but often changing their views can help in that goal. If it is to remain an "encyclopedia that anyone can edit" it must be done by consensus. We can't be expected to read every polemic that someone throws at us but we do need to engage with "deniers", and preferably in a respectful way as that is more likely to engender the kind behavior we would like to see from them. The FAQ is great, btw, (better than the article perhaps!) and un-hiding it seems a good plan to me.--IanOfNorwich (talk) 23:12, 11 May 2011 (UTC)
- I am general agreement with you here, and don't object to unhiding the FAQ. But some of these folks wont' read it no matter how many times we make them run over it. That's where I think we need an attention-getting tag that points them to a specific answer in the FAQ. - J. Johnson (JJ) (talk) 20:52, 14 May 2011 (UTC)
- Re:JJ, I've uncollapsed the FAQ. Feel free to revert if anyone disagrees. Now about the message. I recommend keeping the message in the standard talk-page box, {{tmbox}}. There are a variety of settings to make it "attention getting". If you need help setting it up, just tell me what you want. I don't mind, it's pretty easy to me.
I agree with Rick, but on a different note. Trying to change people's minds is fruitless. They've made up their mind, telling them they're wrong won't change that. I know this is a long read, but a friend recommended a paper to me last week. I think we can develop a different approach from this paper. --Tony 174.52.224.148 (talk) 02:05, 15 May 2011 (UTC)
- Re:JJ, I've uncollapsed the FAQ. Feel free to revert if anyone disagrees. Now about the message. I recommend keeping the message in the standard talk-page box, {{tmbox}}. There are a variety of settings to make it "attention getting". If you need help setting it up, just tell me what you want. I don't mind, it's pretty easy to me.
- I am general agreement with you here, and don't object to unhiding the FAQ. But some of these folks wont' read it no matter how many times we make them run over it. That's where I think we need an attention-getting tag that points them to a specific answer in the FAQ. - J. Johnson (JJ) (talk) 20:52, 14 May 2011 (UTC)
- So no one is suggesting we "make the horse drink". As to what kind of sign could be posted saying "this way to water", I think {{tmbox}} wouldn't be so effective. Maybe something like "Read the Fabulous FAQ [link to answer]". Or even "Duh! There is an answer in the FAQ at ...". And of course, take a parameter for the FAQ answer. - J. Johnson (JJ) (talk) 20:06, 15 May 2011 (UTC)
![]() | Duh!' There is an answer in the FAQ at ... Color it red if you really want. |
- (outdent) To link to Question 4 in the FAQ, enter "Talk:Global warming/FAQ#Q4". The "Talk:Global warming/FAQ" takes you to the FAQ page; the "#Q4" specifies which FAQ within the page.
I think the message should follow something along the lines, "Wikipedia is not a soapbox or forum. Proposals should provide: (1) a specific piece of text to add, modify, or remove; and (2) reliable sources that verify the proposal. If you are citing a 'study', please cite the actual study rather than the press release or a news article." Like you said, JJ, we're not making the horse drink, but showing it where to find water. Anons are going to write proposals, they can at least write something potentially constructive rather than soapbox. The point of the message is to help them find the resources to be able to write something potentially constructive. --Tony 174.52.224.148 (talk) 04:10, 16 May 2011 (UTC)
- Nice, but way too much typing. :-)
- We have a little bit of a fork here. I am looking for something that specifically refers people to an FAQ answer; Tony is talking more about explaining what people need to do to get consideration. Which I think is a good idea, but a different idea. Hmmm, perhaps that could be put into the FAQ? - J. Johnson (JJ) (talk) 21:55, 19 May 2011 (UTC)
- FAQ 6 and FAQ 21 essentially covers how proposals are considered, no need to add it in. Let's talk about your proposal, how to refer people to the FAQ. I think people are aware there's an FAQ, but are reluctant to read it because it is too long. So the first step would be make it more concise:
- Remove FAQ 15. I don't think it's anymore relevant than than people who believe in that the earth is expanding.
- Merge FAQ 18 and FAQ 23. The two seem to be about climate variability, just written in different words.
- Merge FAQ 6 and FAQ 21. Scibaby and soapboxing seems to go together.
- Condensing the FAQ is a good idea. The FAQ bloats because questions get added in when certain talking points become frequent, but outdated points are rarely removed. Short Brigade Harvester Boris (talk) 00:40, 23 May 2011 (UTC)
- I suspect that most of the drive-by-spitballers are not interested in the FAQ, and wouldn't want to bother; they just want to lob a spitball and run off. So I would say that the state of the FAQ, for better or worse, is really irrelevant. What I see as the basic problem (aside from the prevalence of yahoos) is that reiterating an already available answer is essentially a waste of our time and effort. And especially for spitballers we should be able to provide a reasonable answer ("RTFM!") at less cost than they expend in the posting. And a curt response offers less toeholds for an argument. - J. Johnson (JJ) (talk) 23:01, 24 May 2011 (UTC)
- FAQ 6 and FAQ 21 essentially covers how proposals are considered, no need to add it in. Let's talk about your proposal, how to refer people to the FAQ. I think people are aware there's an FAQ, but are reluctant to read it because it is too long. So the first step would be make it more concise:
Media interest
WP:SOAPboxing "not relevant to improving the article" (archived per WP:TALK |
---|
The following discussion has been closed. Please do not modify it. |
For a while I've been watching the google newscount for "global warming" and "peak oil", and whilst peak oil has been rising from around 600 to around 4000 during the time I've been watching, global warming has been going down from around 20,000 (2007) down to 5000. Likewise, public interest in the subject has similarly been draining away. And today, I noticed that in the UK the newsmedia count for peak oil now exceeds that of global warming, and at the present rate I expect that to happen worldwide sometime in the next month or so. So, why isn't this plummeting public and media interest being reflected in the number of articles devoted to this subject? There are currently 65 articles under the category "global warming", (not counting those under "climate change") whilst there are only 43 under "peak oil". And to be frank, this article is long winded, difficult to read and even the climatologists are now asking to use the kind of plain language that has been vigorously rejected here.[1]. — Preceding unsigned comment added by 212.139.52.162 (talk • contribs) 18:58, 5 May 2011 (UTC)
Please read WP:NOTAFORUM and take this discussion to a blog where it belongs. Khukri 08:58, 6 May 2011 (UTC)
Somebody will have to put this to bed. It is an opinion piece. Say Goodnight, Gracie. Tasty monster (=TS ) 00:42, 7 May 2011 (UTC) |
Um
Isn't this just a theory? 174.124.42.87 (talk) 16:36, 10 May 2011 (UTC)
- See the FAQ, specifically Q8. Short Brigade Harvester Boris (talk) 16:49, 10 May 2011 (UTC)
- Q9 caught my eye, while it's right to note that the "atmospheric lifetime of methane (about 10 years) is a lot shorter than that of CO2", should we not also be clear that it sorta converts to CO2 thus continuing to have an effect? [caution: I am not an expert] . . dave souza, talk 17:29, 10 May 2011 (UTC)
Merging of "UNFCCC" and "Politics" sections
I've had an idea of merging these two sections. I think the existing revision of the UNFCCC section is okay, but I'm not satisfied with the politics section (revision below as of 10 May):
Developed and developing countries have made different arguments over who should bear the burden of economic costs for cutting emissions. Developing countries often concentrate on per capita emissions, that is, the total emissions of a country divided by its population.[123] Per capita emissions in the industrialized countries are typically as much as ten times the average in developing countries.[124] This is used to make the argument that the real problem of climate change is due to the profligate and unsustainable lifestyles of those living in rich countries.[123]
On the other hand, Banuri et al. point out that total carbon emissions,[123] carrying capacity, efficient energy use and civil and political rights are very important issues. Land is not the same everywhere. Not only the quantity of fossil fuel use but also the quality of energy use is a key debate point.[citation needed] Efficient energy use supporting technological change might[vague] help reduce excess carbon dioxide in Earth's atmosphere.[citation needed] The use of fossil fuels for conspicuous consumption and excessive entertainment are issues that can conflict with civil and political rights. People[who?] in developed countries argue that history has proven the difficulty of implementing fair rationing programs in different countries because there is no global system of checks and balances or civil liberties.
The Kyoto Protocol, which came into force in 2005, sets legally binding emission limitations for most developed countries.[114] Developing countries are not subject to limitations. This exemption led the U.S. and Australia to decide not to ratify the treaty,[125] [126][127] although Australia did finally ratify the treaty in December 2007.[128] Debate continued at the Copenhagen climate summit and the Cancún climate summit.
The first and second paragraphs do not specify exactly who has made these various arguments. The third paragraph overlaps with the earlier section on the UNFCCC. My suggestion is to remove the "UNFCCC" section and to replace the existing "Politics" section entirely. My suggested revision for the politics section is as follows:
Most countries are Parties to the United Nations Framework Convention on Climate Change (UNFCCC).[111] The ultimate objective of the Convention is to prevent "dangerous" human interference of the climate system.[112] As is stated in the Convention, this requires that GHGs are stabilized in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can proceed in a sustainable fashion.
The Framework Convention was agreed in 1992, but since then, global emissions have risen (US NRC). During negotiations, the G77 (a lobbying group in the United Nations representing 133 developing nations (Dessai, p4)) pushed for a mandate requiring developed countries to "[take] the lead" in reducing their emissions (Grubb, pp.144-145). This was justified on the basis that: the developed world's emissions had contributed most to the stock of GHGs in the atmosphere; per-capita emissions (i.e., emissions per head of population) were still relatively low in developing countries; and the emissions of developing countries would grow to meet their development needs (Liverman, p.290). This mandate was sustained in the Kyoto Protocol to the Framework Convention (Liverman, p.290), which entered into legal effect in 2005 (UNFCCC).
In ratifying the Kyoto Protocol, most developed countries accepted legally binding commitments to limit their emissions. These first-round commitments expire in 2012 (UNFCCC). US President George W. Bush rejected the treaty on the basis that "it exempts 80% of the world, including major population centers such as China and India, from compliance, and would cause serious harm to the US economy" (Dessai, p5).
At the 15th UNFCCC Conference of the Parties, held in 2009 at Copenhagen, several UNFCCC Parties produced the Copenhagen Accord.[117] Parties associated with the Accord (140 countries, as of November 2010 (UNEP, p9)) aim to limit the future increase in global mean temperature to below 2 °C.[118] A preliminary assessment by the United Nations Environment Programme suggests a possible "emissions gap" between the voluntary pledges made in the Accord and the emissions cuts necessary to have a "likely" chance of limiting global warming to 2 deg C above the pre-industrial level (UNEP, pp10-11). To meet the 2 deg C objective, studies generally indicate the need for global emissions to peak before 2020, with substantial declines in emissions thereafter (UNEP, p14).
The 16th Conference of the Parties (COP16) was held at Cancún in 2010. It produced an agreement, not a binding treaty, that the Parties should take urgent action to reduce greenhouse gas emissions to meet a goal of limiting global warming to 2 deg C above pre-industrial temperatures. It also recognized the need to consider strengthening the goal to a global average rise of 1.5 °C.[119]
References:
Admittedly, this is a rather long revision. I think it is an improvement on the existing revision since political points are clearly attributed to particular parties. I also felt that it was important to mention the "emissions gap" in respect of the 2 deg C target. Enescot (talk) 15:50, 11 May 2011 (UTC)
- I'm in favor, again. I tagged parts of the politics section some time ago but haven't got round to doing much positive with it. The old version is a blight. I can't even offer any criticism of your proposed revision, this time; I must be tired.--IanOfNorwich (talk) 22:43, 11 May 2011 (UTC)
- Thanks for your support. Enescot (talk) 19:31, 13 May 2011 (UTC)
- For clarification "degrees C" above (or °C) is Celcius for those who use Fahrenheit (°F). 99.181.148.116 (talk) 09:43, 19 May 2011 (UTC)
- Thanks for your support. Enescot (talk) 19:31, 13 May 2011 (UTC)
Help needed
I'm looking for a way to track interest in the Global warming story and it occurred to me that a good indicator would be the number of comments on this discussion page. But I see that an awful lot of stories have been "archived" and in any case there is a huge number of pages. So, my question is this: is there a way to get a direct dump of comments (I don't need the text just the date). Indeed, perhaps this is a feature that might be worth adding to all Wikipedia pages? 88.104.206.60 (talk) 08:58, 20 May 2011 (UTC)
- Does this give you enough information? it's the history of this article in batches of 5000, with time stamps who etc, but not the content, save it into excel and you can play with it to your heart content. Cheers Khukri 09:44, 20 May 2011 (UTC)
- Yes that is excellent! Thankyou.88.104.206.60 (talk) 10:56, 20 May 2011 (UTC)
- If you have some programming experience, you can access (nearly) all of Wikipedia's data via its http-based API. It's described at mw:API. The API has support in several languages - I found Python a good match. --Stephan Schulz (talk) 11:03, 20 May 2011 (UTC)
- Wow! Not sure I'll need anything that complex. Thanks88.104.206.60 (talk) 12:16, 20 May 2011 (UTC)
- If you have some programming experience, you can access (nearly) all of Wikipedia's data via its http-based API. It's described at mw:API. The API has support in several languages - I found Python a good match. --Stephan Schulz (talk) 11:03, 20 May 2011 (UTC)
- Yes that is excellent! Thankyou.88.104.206.60 (talk) 10:56, 20 May 2011 (UTC)
- You can also use a hit counter to look at daily page views for any wikipedia article back to december 2007. For instance, it's interesting that there wasn't a big spike in November 2009 as one might expect given the hubub surrounding the CRU hack near the end of the month. Sailsbystars (talk) 19:04, 20 May 2011 (UTC)
Inertia in the climate system and energy sector
![]() | It has been suggested that this page be merged into greenhouse effect. (Discuss) Proposed since June 2011. |
I've prepared a revision to the section on external forcing, concentrating on the sub-section on greenhouse gases:
External forcing refers to processes external to the climate system (though not necessarily external to Earth) that influence climate. Climate responds to several types of external forcing, such as changes in atmospheric composition (e.g., the concentrations of heat-trapping greenhouse gases), changes in solar luminosity (i.e., the sun's output (IPCC FAQ 2.1 Natural changes)), volcanic eruptions, and variations in Earth's orbit around the Sun.[31] Attribution of recent climate change focuses on the first three types of forcing. Orbital cycles vary slowly over tens of thousands of years and thus are too gradual to have caused the temperature changes observed in the past century. Any human-induced climate change will occur against the "background" of natural variations in climate (2001 ts).
Greenhouse gases
The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet's lower atmosphere and surface. It was proposed by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896.[32]
Naturally occurring greenhouse gases have a mean warming effect of about 33 °C (59 °F).[33][C] The major greenhouse gases are water vapor, which causes about 36–70 percent of the greenhouse effect; carbon dioxide (CO2), which causes 9–26 percent; methane (CH4), which causes 4–9 percent; and ozone (O3), which causes 3–7 percent.[34][35][36] Clouds also affect the radiation balance, but they are composed of liquid water or ice and so have different effects on radiation from water vapor.
Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing (see below) from CO2, methane, tropospheric ozone, CFCs and nitrous oxide. The concentrations of CO2 and methane have increased by 36% and 148% respectively since 1750.[37] These levels are much higher than at any time during the last 800,000 years, the period for which reliable data has been extracted from ice cores.[38][39][40][41] Less direct geological evidence indicates that CO2 values higher than this were last seen about 20 million years ago.[42] Fossil fuel burning has produced about three-quarters of the increase in CO2 from human activity over the past 20 years. The rest of this increase is caused mostly by changes in land-use, particularly deforestation.[43]
The increase in the concentration of greenhouse gases in the atmosphere can be calculated as a change in the radiative forcing of the climate (IPCC FAQ 2.1 Box 2.1). Radiative forcing is a measure of how various factors alter the energy balance of the Earth's atmosphere. A positive radiative forcing will tend to increase the energy of the Earth-atmosphere system, leading to a warming of the system. Between the start of the Industrial Revolution in 1750, and the year 2005, the increase in the atmospheric concentration of carbon dioxide lead to a positive radiative forcing of about 1.66 watts per meter squared (SPM 2007).
Greenhouse gases remain in the atmosphere for different lengths of time (IPCC FAQ 10.3). For carbon dioxide, natural processes currently remove more than half of the CO2 emitted from the atmosphere within a century. Some fraction, however, remains in the atmosphere for many thousands of years.
The governments of most countries in the world have agreed that the concentrations of greenhouse gases in the atmosphere should be stabilized at a safe level (see the politics section). To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to be completely eliminated (IPCC FAQ 10.3). The present rate of emission of carbon dioxide into the atmosphere greatly exceeds its rate of removal by natural processes. This is analogous to a flow of water into a bathtub (Sterman and Sweeney, p221). So long as the tap runs water (analogous to the emission of carbon dioxide) into the tub faster than water escapes through the plughole (the natural removal of carbon dioxide from the atmosphere), then the level of water in the tub (analogous to the concentration of carbon dioxide in the atmosphere) will continue to rise.
Over the last three decades of the 20th century, economic and population growth were the main drivers of increases in greenhouse gas emissions.[44] CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change.[45][46]:71 Emissions can be attributed to different regions. The two figures opposite show annual greenhouse gas emissions for the year 2005, including land-use change. Attribution of emissions due to land-use change is a controversial issue Banuri, p.93; Liverman, p.289). For example, concentrating on more recent changes in land-use (as the figures opposite do) is likely to favour those regions that have deforested earlier, e.g., Europe.
Future emissions
The future level of greenhouse gas emissions is highly uncertain (Fisher). One factor that will affect the future level of emissions are current and future investment decisions made in the energy sector (synth 2007; sachs, p112). Energy-sector investments, e.g., coal-fired power plants, have long lifetimes, and therefore also have long term impacts on greenhouse gas emissions.
Analysts have developed scenarios of how emissions might change in the future. Emissions in these scenarios vary according to different assumptions over future economic, social, technological, and natural developments (SRES). In 2000, the Intergovernmental Panel on Climate Change (IPCC) published a special report on emissions scenarios. This report contains a set of 40 emissions scenarios that cover a wide range of possible future emissions out to the end of the 21st century (morita). Six representative scenarios from the IPCC's report have been used to project what the future atmospheric concentration of carbon dioxide might be. These scenarios suggest an atmospheric concentration of between 540 and 970 parts-per-million (ppm) in the year 2100 (Synth 2001). This compares to a pre-industrial concentration of 280 ppm, and in 2008, a concentration of about 385 ppm (US GCRP, p13).
References:
- 2001 ts box 1[4]
- Banuri PDF [5]
- Fisher [6]
- IPCC FAQ 10.3 [7]
- IPCC FAQ 2.1 [8]
- Liverman PDF [9]
- Morita [10]
- Sachs PDF [11]
- SPM 2007 Figure SPM 2 [12]
- SRES [13]
- Sterman and Sweeney PDF [14]
- Synth 2001 Question 3 [15]
- Synth 2007, following Table SPM 5 [16]
- US GCRP, PDF [17]
My main concern is that the flow-stock nature of climate change is not mentioned in the present revision of the article. Generally I am concerned that the existing article does not present information in a way that is easy enough to understand for the general reader. The flow-stock issue is crucial to understanding climate change - see the Sterman and Sweeney paper referenced above. I am also concerned that inertia in the energy system is not mentioned either. In my opinion, inertia is crucial to understanding policy issues related to climate change.
Another issue is that of emissions due to land-use change. In the politics section, the existing revision of the article includes diagrams that show regional GHG emissions, which includes emissions from land-use change. Emissions from land-use change is a controversial subject, and this needs to be mentioned. I'd prefer a broader discussion of emissions to be included, e.g., historical emissions, but I'm aware of the fact that the article is already far too long.
I've added a brief description of radiative forcing. I'd prefer an explanation of external forcing that is easier to understand. I know of the scales analogy used by potholer54. Perhaps a later revision could include this?
I've removed this:
Fossil fuel reserves [as suggested by the SRES scenarios] are sufficient to reach these [GHG concentration] levels and continue emissions past 2100 if coal, oil sands or methane clathrates are extensively exploited
This is not supported by the cited source. Different SRES scenarios make different assumptions over the future availability of fossil fuels (4.4.6.1 onwards). These are assumptions, but the sentence above gives the impression that the SRES projections are made with absolute certainty. Enescot (talk) 16:28, 26 May 2011 (UTC)
- Quite aside from the content, the citations ("2001 ts box", "Banuri PDF", "Fisher") are quite inadequate; they need to be in proper form. - J. Johnson (JJ) (talk) 16:40, 26 May 2011 (UTC)
- Hello. I've used the citation style above purely for this talk page. If I go ahead with my suggested revision, I'll use the same citation style as the rest of the article. Enescot (talk) 13:55, 27 May 2011 (UTC)
- Haven't had a chance to give it a thorough read yet or compare with the existing text but "To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to be completely eliminated." is wrong (even if the IPCC says it!) 'net' emissions need to be zero to stabilize the atmospheric concentration of carbon dioxide at a constant level.--IanOfNorwich (talk) 22:45, 26 May 2011 (UTC)
- I assume that the IPCC FAQ is referring to net carbon dioxide emissions from human activities. This is how the IPCC dealt with the issue of emissions and stabilization in the Third Assessment Report (see 5.3 and [18]). I agree that mentioning net emissions would be helpful. In my view it would require an explanation of what "net" actually means in this context, e.g.,:
- The governments of most countries in the world have agreed that the concentrations of greenhouse gases in the atmosphere should be stabilized at a safe level (see the politics section). Stabilizing the concentrations of greenhouse gases in the atmosphere would need to account both for processes that remove GHGs from the atmosphere, as well as processes that add GHGs to the atmosphere, i.e., net GHG emissions. To stabilize the atmospheric concentration of carbon dioxide at a constant level, net carbon dioxide emissions would need to be completely eliminated (IPCC FAQ 10.3).
- The present net rate of emission of carbon dioxide into the atmosphere greatly exceeds its net rate of removal by natural processes. This is analogous to a flow of water into a bathtub (Sterman and Sweeney, p221). So long as the tap runs water (analogous to the emission of carbon dioxide) into the tub faster than water escapes through the plughole (the natural removal of carbon dioxide from the atmosphere), then the level of water in the tub (analogous to the concentration of carbon dioxide in the atmosphere) will continue to rise.
- Enescot (talk) 14:24, 28 May 2011 (UTC)
- Why not forget the word 'net' (I agree it might be confusing in this context) and just replace "To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to be completely eliminated." with "To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to equal the rate of carbon dioxide removal from the atmosphere."?--IanOfNorwich (talk) 21:47, 28 May 2011 (UTC)
- In my opinion, breaking down the explanation into two sentences rather than one might make things easier to understand. I would prefer keeping the sentence about net emissions for this reason. I think that the revision could, however, be rewritten to make things clearer:
- Why not forget the word 'net' (I agree it might be confusing in this context) and just replace "To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to be completely eliminated." with "To stabilize the atmospheric concentration of carbon dioxide at a constant level, carbon dioxide emissions would need to equal the rate of carbon dioxide removal from the atmosphere."?--IanOfNorwich (talk) 21:47, 28 May 2011 (UTC)
- The governments of most countries in the world have agreed that the concentrations of greenhouse gases in the atmosphere should be stabilized at a safe level (see the politics section). Stabilizing the concentrations of greenhouse gases in the atmosphere would need to account both for processes that remove GHGs from the atmosphere, as well as processes that add GHGs to the atmosphere, i.e., net GHG emissions.
- At present, human activities are adding emissions of carbon dioxide into the atmosphere far faster than they are being removed. This is analogous to a flow of water into a bathtub (Sterman and Sweeney, p221). So long as the tap runs water (analogous to the emission of carbon dioxide) into the tub faster than water escapes through the plughole (the natural removal of carbon dioxide from the atmosphere), then the level of water in the tub (analogous to the concentration of carbon dioxide in the atmosphere) will continue to rise. To stabilize the atmospheric concentration of carbon dioxide at a constant level, emissions would essentially need to be completely eliminated. It is estimated that reducing carbon dioxide emissions 100% below their present level (i.e., complete elimination) would lead to a slow decrease in the atmospheric concentration of CO2 by 40 ppm over the 21st century.
- I think it is necessary to mention that only an effective elimination of CO2 emissions would lead to stabilization. Not mentioning this might give readers the false impression that a less stringent level of emissions reduction would lead to stabilization. Enescot (talk) 15:30, 30 May 2011 (UTC)
- I'd rather these changes be taken one at a time rather than in bulk, so they can be evaluated more easily. As a first specific remark, we should de-emphasize SRES since those scenarios are not being used for AR5. Short Brigade Harvester Boris (talk) 14:30, 27 May 2011 (UTC)
- Agreed on the first point you raise. Although I think the issue of inertia is important, I think a higher priority is to point out the controversy surrounding emissions from land-use change. First of all, I think that the existing article's diagrams of regional emissions should be moved from the politics section to the greenhouse gases section. This would allow a brief explanation of these diagrams in the body of the article's text. I think it is more appropriate to explain these diagrams in the greenhouse gases section of the article rather than the politics section. The text that I've added is in bold:
- [...] Over the last three decades of the 20th century, economic and population growth were the main drivers of increases in greenhouse gas emissions.[44] CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change.[45][46]:71 Emissions can be attributed to different regions. The two figures opposite show annual greenhouse gas emissions for the year 2005, including land-use change. Attribution of emissions due to land-use change is a controversial issue (Banuri, p.93; Liverman, p.289). For example, concentrating on more recent changes in land-use (as the figures opposite do) is likely to favour those regions that have deforested earlier, e.g., Europe.
- Emissions scenarios, estimates of changes in future emission levels [...]
- References:
- I don't agree with you about the SRES scenarios. Temperature projections using six of the SRES scenarios are already referred to in the article. In my view, it therefore makes sense to use them also when referring to projections of the future atmospheric concentration of CO2.
- I'm uncertain as to which scenarios you'd use instead of the SRES ones. A very wide range of emissions scenarios have been published. I'm unclear on how you would objectively choose a representative set of these scenarios to mention in this article. At the time of the IPCC fourth assessment report, the SRES scenarios were still comparable in range to other baseline scenarios in the scientific literature [21]. More recent assessments by the US Global Change Research Program (PDF, pp22-24) and US National Research Council (PDF, p2) refer to the SRES scenarios, presumably because they are still thought to be relevant. The projected concentration of CO2 based on the International Energy Agency's reference scenario of World Energy Outlook 2009 (PDF, pp190-191) appears to lie within the range of the SRES projections. You mention the fact that the SRES scenarios are not being used in the IPCC fifth assessment report. I don't know how this is relevant to improving the article at present. The fifth assessment report has not been published yet, nor have the new scenarios that are being developed for it. Enescot (talk) 18:21, 29 May 2011 (UTC)
- Note my suggestion is to "de-emphasize" SRES, not omit it. The CMIP5 runs (which will be used for AR5) are using "representative concentration pathways" (RCPs) rather than SRES. Basically a RCP is a concentration pathway that produces a given radiative forcing by 2100, so RCP4.5 gives a forcing of 4.5 W/m2, RCP8.5 gives a forcing of 8.5 W/m2 and so on. Output from the first runs is beginning to hit the ESG and we will begin seeing papers very soon. Short Brigade Harvester Boris (talk) 19:11, 29 May 2011 (UTC)
- My mistake. What change do you think would be appropriate? Enescot (talk) 00:06, 1 June 2011 (UTC)
- Simply include a mention of SRES in describing how simulations used in AR4 were set up, not a full paragraph with explanatory details. We have a whole article Special Report on Emissions Scenarios for anyone who wants to look further. Short Brigade Harvester Boris (talk) 03:13, 1 June 2011 (UTC)
- My mistake. What change do you think would be appropriate? Enescot (talk) 00:06, 1 June 2011 (UTC)
- Note my suggestion is to "de-emphasize" SRES, not omit it. The CMIP5 runs (which will be used for AR5) are using "representative concentration pathways" (RCPs) rather than SRES. Basically a RCP is a concentration pathway that produces a given radiative forcing by 2100, so RCP4.5 gives a forcing of 4.5 W/m2, RCP8.5 gives a forcing of 8.5 W/m2 and so on. Output from the first runs is beginning to hit the ESG and we will begin seeing papers very soon. Short Brigade Harvester Boris (talk) 19:11, 29 May 2011 (UTC)
- I'm uncertain as to which scenarios you'd use instead of the SRES ones. A very wide range of emissions scenarios have been published. I'm unclear on how you would objectively choose a representative set of these scenarios to mention in this article. At the time of the IPCC fourth assessment report, the SRES scenarios were still comparable in range to other baseline scenarios in the scientific literature [21]. More recent assessments by the US Global Change Research Program (PDF, pp22-24) and US National Research Council (PDF, p2) refer to the SRES scenarios, presumably because they are still thought to be relevant. The projected concentration of CO2 based on the International Energy Agency's reference scenario of World Energy Outlook 2009 (PDF, pp190-191) appears to lie within the range of the SRES projections. You mention the fact that the SRES scenarios are not being used in the IPCC fifth assessment report. I don't know how this is relevant to improving the article at present. The fifth assessment report has not been published yet, nor have the new scenarios that are being developed for it. Enescot (talk) 18:21, 29 May 2011 (UTC)
- I agree with Boris when he said "I'd rather these changes be taken one at a time rather than in bulk, so they can be evaluated more easily." More importantly, I'm somewhat opposed to expanding a whole section on greenhouse gas here, without first discussing a comprehensive approach to the info you want to add with the overlapping info found on an existing article about the greenhouse effect and a separate overlapping one on greenhouse gasses. IMO all this info ought to be merged, with just the highlights here and a link to a single separate main article on the ins and outs of how the gasses do what they do. Collating all this info with a minimum of redundancy is a worthy task. Thanks for your interest. BTW, I share your desire to make internal/external forcing more clear. On a small point, there seems to be confusion about how to parse various impacts of the lithosphere. See my comment under climate-change talk for volcanos. NewsAndEventsGuy (talk) 21:59, 2 June 2011 (UTC)
- Discussion about my proposed merger of greenhouse effect and greenhouse gas is here: Talk:greenhouse effect#Merger proposal NewsAndEventsGuy (talk) 10:16, 3 June 2011 (UTC)
Lede is bloating
While some of the recent edits have added helpful explanations, the lede has now grown too unwieldy and lacks flow. The lede would be more effective if the details be pared back or moved to later in the text, and the current seven choppy paragraphs condensed down to no more than four per WP:LEDE. Short Brigade Harvester Boris (talk) 03:03, 1 June 2011 (UTC)
- Thanks, Boris, you're right its bloated. I already made a couple moves out of the lede for stuff I thought would be non-controversial. Apologies if I erred.
I PROPOSE moving the paragraphs starting "The uncertainty in IPCC's estimates" to the climate models section
Also.... today I added pithy language from the most recent research about why this matters (the clear and present danger paragraph). In keeping with WP:LEDE I think that is a good "hook", so I PROPOSE moving the following paragraph that describes some of the specific responses in general could move down to the intro paragraph in "Attributed and expected effects"
Will that help? And as a new editor, how do I know when enough time has gone by for soliciting comment here before going ahead with those changes? Or if you just wanna do it, that'd be fine by me. NewsAndEventsGuy (talk) 03:53, 2 June 2011 (UTC)
- I propose reverting to this revision. My 2 cents. -Atmoz (talk) 16:49, 3 June 2011 (UTC)
IPCC Models
NewsAndEventsGuy has added to the reasons for uncertainty in the IPCC predictions "(4) an assumption in the models that temperature will rise in a linear fashion when in fact the rate of global temperature rise is accelerating[14]" . This is at odds with my understanding that the models used do not make any direct assumption about the shape of the temperature curve. I would have removed it but it appears to be supported by what seems a legitimate reference. --IanOfNorwich (talk) 00:04, 2 June 2011 (UTC)
- I removed it too, but he added it back. You are of course correct that the models make no assumption whatsoever about the relationship between CO2 and temperature, be it linear, logarithmic, serpentine or whatever. Trouble is, it would be hard to find a reference on such an obvious point. We could point to papers on model formulation that give the governing equations, etc. but we might not be able to find a reference that explicitly says "AOGCMs make no assumption about the shape of the temperature response." Thompson is an outstanding paleoclimatologist but he's not a modeler and the error he makes is of a fairly common sort. Short Brigade Harvester Boris (talk) 02:35, 2 June 2011 (UTC)
- Beat me, guys, I'm not a climate modeler either. It's my guess that Dr Thompson would be pleased to respond to an inquiry for clarification. Since I stuck it in there, I will be happy to drop him an email. If this falls off my radar, please post a reminder on my talk page in a month or so.NewsAndEventsGuy (talk) 03:43, 2 June 2011 (UTC)
- IanOfNorwich and Short Brigade Harvester Boris are both correct about models not making assumptions about the shape of the temperature response to forcings. I swear I've seen this exact point addressed at realclimate, but I can't find a good reference right now. There's a related comment in this post:
“ | For the case of the global mean temperature however, we have enough modelling experience to have confidence that, to first order, global mean surface temperatures at decadal and longer timescales are a reasonably linear function of the global mean radiative forcings. This result is built in to simple energy balance models, but is confirmed (more or less) by more complex ocean-atmosphere coupled models and our understanding of long term paleo-climate change. | ” |
- But that's a bit too generic. On the other hand, this Science paper explains in part how the models work, but is not explicit on this point. Neither is this related blog post. Maybe it's best to cite the paper describing one of the models? Or just email Gavin Schmidt? - Parejkoj (talk) 03:07, 3 June 2011 (UTC)
- Good idea, P. I did email Dr T, but for all I know he's on another expedition and not reading fan mail. I'll give it a week or so and then post something on RC or email Garvin as you suggest. NewsAndEventsGuy (talk) 10:12, 3 June 2011 (UTC)
- Are you happy if we remove it for the time being, NewsAndEventsGuy? The thing is this just can't be correct "an assumption in the models that temperature will rise in a linear fashion". If it were the temperature rise output from models referenced by the IPCC would have to output linear temperature responses choosing only a gradient, which they don't. The underlying point that models underestimate positive feedback 'may' be true but we're not really in a better position to judge than the climate modelers, without some very detailed research.--IanOfNorwich (talk) 10:45, 3 June 2011 (UTC)
- Sure, that works. I wasted it already. If I come up with anything to revisit the topic I'll post it here, and call attention on TALK for you and Boris to mull over before going live. This subsection can get wasted in a few months if there's no changes. NewsAndEventsGuy (talk) 11:51, 3 June 2011 (UTC)
- Many of the forcings are not properly accounted for, and cloud models are very unsophisticated. None of this really captured here. Restreusion (talk) 04:46, 4 June 2011 (UTC)
GAIA Theory and Climate Change
I was astonished after reading this article about Climate Change to see that no single reference is made to the GAIA theory of James Lovelock. As found some decades ago, the biosphere has a very powerful regulatory action on the climate. Hence, any serious climate mathematical model must include the important effects of the biosphere on the climate. Taking into account that these biological effects are very complex and difficult to model, the outcome of these climate models should have a high degree of uncertainty. — Preceding unsigned comment added by Manuel.frn (talk • contribs) 00:59, 4 June 2011 (UTC)
uncertainty?
Just visiting after a long absence. I'm pleased to see that language I helped get inserted and WMC battled hard to keep out, is still around in some form.
- "The uncertainty in IPCC's estimates arises from (1) the use of models with differing sensitivity to greenhouse gas concentrations, the use of differing estimates of humanities' future greenhouse gas emissions, and (3) any additional emissions from climate feedbacks that were not included in the models IPCC used to prepare its report, i.e., greenhouse gas releases from permafrost."
Unfortunately, given the wikipedia cadre culture, this was the best that we could do. We enumerated what sources of uncertainty are included in the IPCC projections. Let unstated are the sources of uncertainty introduced by just about every diagnostic study, from Andrea Roesch's documentation of surface albedo bias as large as the CO2 forcing increase itself, Wentz's documentation that none of the climate models reproduce more than half of the observed increase in precipitation associated with the recent warming, and of course, we still don't know whether the net feedbacks to CO2 forcing are strongly positive as correlated in all the models, or actually negative corresponding to sensitivities less than 1 degree C.
Has the culture changed here at all? Can we actually mention that the projection ranges were not adjusted for the problems documented in the diagnostic literature, some as large as the CO2 forcing itself, or must we continue to be satisfied with this simple enumeration of what was included? I.e., is there any point in climate science literate person sticking around?--Silverback (talk) 10:36, 4 June 2011 (UTC)
- Wikipedia articles under general sanctions
- Wikipedia featured articles
- Featured articles that have appeared on the main page
- Featured articles that have appeared on the main page once
- Old requests for peer review
- FA-Class Weather articles
- Top-importance Weather articles
- Unsorted weather articles
- WikiProject Weather articles
- FA-Class Environment articles
- Unknown-importance Environment articles
- WikiProject Climate change articles
- FA-Class Geology articles
- High-importance Geology articles
- High-importance FA-Class Geology articles
- WikiProject Geology articles
- FA-Class Arctic articles
- High-importance Arctic articles
- WikiProject Arctic articles
- Wikipedia pages referenced by the press
- Articles to be merged from June 2011