Talk:Climate change

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 On a different note, I don't think the FAQ is effective, because anons could easily disagree with it as out-of-date/inaccurate/ect.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)

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)

  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)

(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:

1. Remove FAQ 15. I don't think it's anymore relevant than than people who believe in that the earth is expanding.
2. Merge FAQ 18 and FAQ 23. The two seem to be about climate variability, just written in different words.
3. Merge FAQ 6 and FAQ 21. Scibaby and soapboxing seems to go together.

What do you think? --Tony 174.52.224.148 (talk) 00:19, 23 May 2011 (UTC)

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)

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)

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

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

Greenhouse effect schematic showing energy flows between space, the atmosphere, and earth's surface. Energy exchanges are expressed in watts per square meter (W/m²).

This graph is known as the "Keeling Curve" and it shows the long-term increase of atmospheric carbon dioxide (CO₂) concentrations from 1958-2008. Monthly CO₂ measurements display seasonal oscillations in an upward trend; each year's maximum occurs during the Northern Hemisphere's late spring, and declines during its growing season as plants remove some atmospheric CO₂.

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.

Per capita greenhouse gas emissions in 2005, including land-use change.

Total greenhouse gas emissions in 2005, including land-use change.

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[1]
• Banuri PDF [2]
• Fisher [3]
• IPCC FAQ 10.3 [4]
• IPCC FAQ 2.1 [5]
• Liverman PDF [6]
• Morita [7]
• Sachs PDF [8]
• SPM 2007 Figure SPM 2 [9]
• SRES [10]
• Sterman and Sweeney PDF [11]
• Synth 2001 Question 3 [12]
• Synth 2007, following Table SPM 5 [13]
• US GCRP, PDF [14]

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 [15]). 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:

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:

Per capita greenhouse gas emissions in 2005, including land-use change.

Total greenhouse gas emissions in 2005, including land-use change.

[...] 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:

• Banuri PDF [16]
• Liverman PDF [17]

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 [18]. 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)

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)

I've added a "failed verification" tag to the following sentence:

Fossil fuel reserves are sufficient to reach these levels and continue emissions past 2100 if coal, oil sands or methane clathrates are extensively exploited.

The above refers to the six SRES marker scenarios, mentioned in the greenhouse gases section of the article. I've already commented on the problem of the above sentence earlier on in this section. Enescot (talk) 01:32, 6 June 2011 (UTC)

A - The 'failed verification' tag produces text indicating that the cited reference does not contain information corroborating the statement. For this case that is false and thus this tag should not have been used.

B - The argument above, that not all SRES scenarios assume sufficient fossil fuel availability to hit the stated emissions scenario, is irrelevant because the sentence specifies a set of assumptions ("...if coal, oil sands or methane clathrates are extensively exploited") where they would be.

As such, I don't see any basis for this tag. --CBD 17:54, 6 June 2011 (UTC)

Hi. Thanks for clarifying the basis for the statement. I'm not sure I agree with you. I interpret this (I'll label it (a) for reference):

Fossil fuel reserves are sufficient to reach these levels and continue emissions past 2100 if coal, oil sands or methane clathrates are extensively exploited.

as "we have a certain amount of fossil fuel reserves, and if we choose to use them, these concentrations may be reached". I think the phrase "are sufficient" in (a) is crucial. Even though a caveat is used in the form of "if...," the caveat only appears to apply to whether or not fossil fuel reserves are actually used. The caveat does not appear to place in doubt whether reserves are sufficient to meet the required demand.

For this reason, I don't accept (a) (or at least my interpretation of it), due to the uncertain level of fossil fuel availability (see the TAR synthesis report, paragraph 7.27 and fig. 7-5). This is something SRES makes a point of addressing by using scenarios that "explore a wider domain of uncertainty on future fossil-resource availability." My view is that the introduction to the paragraph on scenarios already addresses this point indirectly:

Emissions scenarios, estimates of changes in future emission levels of greenhouse gases, have been projected that depend upon uncertain economic, sociological, technological, and natural developments

The sentence above also appears to be consistent with the summary presented in the SRES [19]. If fossil fuel reserves are to be mentioned directly, my own view is that it should be done in a way that is less open to interpretation. I suggest:

Emissions scenarios, estimates of changes in future emission levels of greenhouse gases, have been projected that depend upon uncertain economic, sociological, technological, and natural developments.[51] In most scenarios, emissions continue to rise over the century, while in a few, emissions are reduced.[52][53] These emission scenarios, combined with carbon cycle modelling, have been used to produce estimates of how atmospheric concentrations of greenhouse gases will change in the future. Using the six IPCC SRES "marker" scenarios, models suggest that by the year 2100, the atmospheric concentration of CO2 could range between 541 and 970 ppm.[54] This is an increase of 90-250% above the concentration in the year 1750. Fossil fuel reserves are abundant, and will not limit carbon emissions in the 21st century.

• Source: IPCC WG3 2001 SPM, paragraph 6 - "(figure SPM.2) shows that there are abundant fossil fuel resources that will not limit carbon emissions during the 21st century"

As perhaps you already know, fossil fuel availability is discussed in the SRES sub-article. Personally I don't think it is necessary to mention it in this top-level article. Enescot (talk) 02:12, 9 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)

Just posted my first effort at condensing. Article-improvement oriented comment welcome.NewsAndEventsGuy (talk) 12:03, 4 June 2011 (UTC)

I propose reverting to this revision. My 2 cents. -Atmoz (talk) 16:49, 3 June 2011 (UTC)

I want to assume you have good intentions and intend for the article to be improved by doing this. I note it would result in the deletion of numerous verifiable citations to very recent peer reviewed research on the subject. How will this improve the article, IYO? NewsAndEventsGuy (talk) 12:03, 4 June 2011 (UTC)

While some of the changes are improvements, my overall assessment is that the lede has become fragmented and wordy, and puts too much emphasis on small-minority perspectives that do not have broad scientific acceptance (e.g., Joe Romm). I can see an argument for taking it back to an earlier version and introducing changes at a more measured pace. Short Brigade Harvester Boris (talk) 17:22, 4 June 2011 (UTC)

Generally, I liked Atmoz' edits (thanks). I may address the biggest items that were deleted at another time (and slower). Boris, do you still feel the Lede still bloated , or is this subsection resolved to your satisfaction? NewsAndEventsGuy (talk) 18:30, 5 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)

I give more attention to signed comments.NewsAndEventsGuy (talk) 11:38, 4 June 2011 (UTC)

Sorry, I guess its signed. See climate model and climate change; Not only the biosphere but the other four components of the climate system would be 100% perfectly represented in the perfect climate model. If you'd like to try drafting some text about uncertainty in the models, please do, and then your comment can be evaluated better. Include verifiable citations.NewsAndEventsGuy (talk) 12:09, 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. Left 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)

I'll take credit for adding #3 in the pullquote above. Its not clear to me what your complaint is. Could you write a couple sentences of draft text with verifiable citations to help clarify your meaning? Thanks in advance. NewsAndEventsGuy (talk) 11:36, 4 June 2011 (UTC)

The complaint, originally was, and still is, that the citing a range of projections in a scientific context, such as that attributed to the IPCC, gives the impression that the range brackets the uncertainty in the methods applied to produce that range. However, in this case, none of the uncertainty introduced by documented problems such as those with clouds and surface albedo, have been included or estimated for that range. I already mentioned diagnostic work by Roesch and Wentz, one could easily add the separate work by Camp and Tung and by Lean showing that the models underrepresent the signature of the solar cycle seen in the observations, or the work showing that models under represent the arctic melting, etc.

The way it was left previously, is that WMC and company stated that the range incorporated such uncertainty, but were unable to back it up. The quote above, at least for items 1 and 2, were the only sources of the range specifically supportable within the AR4 report. But the clique at the time, successfully resisted including not just a statement to the effect that the range doesn't include uncertainty from known errors in the models, but resisted attempts to actually cite and report diagnostic results.--Silverback (talk) 12:56, 4 June 2011 (UTC)

With respect, please note that the Arbitration Committee has taken a dim view of battleground editing, including casting aspersions on other editors. With this in mind it is likely they would view your references to "cadres" and "cliques" in a poor light. Regards, Short Brigade Harvester Boris (talk) 13:58, 4 June 2011 (UTC)

With even more respect, I took a dim view of it too, as did many other editors that gave up.--Silverback (talk) 02:31, 5 June 2011 (UTC)

With my respect too, your response was non-responsive. Please draft a couple sentences of text with verifiable citations to

clarify your meaning. Meanwhile, I am working on moving the IPCC uncertainty text from the LEDE to the section on models. See

discussion about the LEDE above. NewsAndEventsGuy (talk) 14:27, 4 June 2011 (UTC)

I see, once again we have to prove a negative, such as none of the diagnostic problems are incorporated in the range. Anything else is original research?--Silverback (talk) 02:33, 5 June 2011 (UTC)

No, I'm just saying I can't trust myself to infer what change you want me to take my free time to write up. So instead,

I'm simply asking you to illustrate your complaint by drafting text. You seem to have plenty of time to repeat your

complaint, after all. Wouldn't it be more productive proposing the specific text you'd like to see added? Assuming you

want to improve the article, that is. NewsAndEventsGuy (talk) 02:32, 5 June 2011 (UTC)

We'll see how productive it is. I'm on a trip right now away from all the quotes from the diagnostic literature I want to get it. I'll propose some text when I get back. Thanx.--Silverback (talk) 02:35, 5 June 2011 (UTC)

Degree of consensus on warming and on causation

Is the degree of unanimity the same for "air temp is up" as for "we caused it"? Or is it true, as I seem to recall from polls of scientists, that there is more agreement about the observed temperature increase than about what caused it?

I seem to recall that only about 5% or 10% disagree with the 1.5 F (0.8 C) atmosphere temp increase, while 20% or more still have questions about the cause.

I'm not saying there isn't a "consensus" because we Wikipedians apparently have agreed that 75% to 80% is a consensus. I'm just saying that it looks like the level of consensus is different for the two issues. --Uncle Ed (talk) 19:22, 4 June 2011 (UTC)

Surprisingly, the Doran&Zimmerman paper found that 96.2% of active climate scientist support warming, and 97.4% think human activity is a significant contributing factor to changing mean global temperature. So the consensus amongst experts is very much the same (modulo statistical noise). --Stephan Schulz (talk) 19:40, 4 June 2011 (UTC)

Note to Ed, it's not that "we Wikipedians apparently have agreed" that there is a consensus, but that the National Academy of Sciences and other august bodies have agreed there is a consensus. Short Brigade Harvester Boris (talk) 19:45, 4 June 2011 (UTC)

Stephan, sorry if I wasn't clear: I did not mean to profess lack of awareness that over 95% of climate scientists regard human activity to be significant and when I said that 20% or more still have questions about the cause I could have been clearer. The issue is not whether human activity has a measurable or "significant" impact on warming. Lindzen, et al., all agree. The issue is rather, as a UN agency reported, whether most of the warming is caused by human activity.

Do my remarks make more sense now, in light of that clarification? --Uncle Ed (talk) 20:25, 4 June 2011 (UTC)

I don't know what "a UN agency" reported. The most cited and respected opinion is probably that of the IPCC, which is not a UN agency. And the IPCC did not report that "most of the warming is caused by human activity", but rather, that "most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations" (emphasis mine), a much more differentiated view. --Stephan Schulz (talk) 22:02, 4 June 2011 (UTC)

Ed, verifiable citations or no discussion please. NewsAndEventsGuy (talk) 20:40, 6 June 2011 (UTC)

To Stephan: the distinction you are drawing is like saying that the line Play it again, Sam never occurs in "Casablanca" and then turning right around and conceding that Ilsa Lund said, "Play it once, Sam. For old times' sake." (To play something for old time's sake is arguably to "play it again".)

Anyway, the question to which I'm still waiting for answer is this: is it true, as I seem to recall from polls of scientists, that there is more agreement about the observed temperature increase than about what caused it?

I'm sorry, but if you don't see the important difference between "most of the warming is caused by human activity" and "most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations", I don't know what to do. The reason why there is strong consensus for both the statement about the observed warming and the statement about the anthropogenic causes is because the second is stronger qualified than the first to begin with. I assume you have seen sources ("polls of scientists"), so why not present them? Or take a look at Scientific opinion on climate change#Surveys_of_scientists_and_scientific_literature. (Anderegg, Prall, Harold, and Schneider, 2010) found high agreement with the IPCC in general. You already dismissed Doran & Zimmerman. (Bray and von Storch, 2008) has some problems (it has not been published in a peer-reviewed journal), but it shows about 94% agreement for "there is climate change going on now" (note the general term) and 84% for "CC is, or will be, a result of anthropogenic causes", but with a shift to lower degrees of certainty for the second question. --Stephan Schulz (talk) 10:38, 7 June 2011 (UTC)

"as I seem to recall from polls of scientists"

I'm with Stephan on this.... verifiable citations to support your question or stop, please NewsAndEventsGuy (talk) 11:08, 7 June 2011 (UTC)

To Stephan, of course I get the distinction between is caused by and is very likely due to (I've known about the nuanced statement for years ... probably for most of the time I've been writing about climate since 2001.) That is why I am proposing that we reveal as early as possible in the article that there is less than complete unanimity amoung climate scientists that "most global warming" (for any period you care to name) is due to anthropogenic causes.

1. Some CC (i.e., a "significant" or "discernible" amount) is the result of anthropogenic causes: 85% to 98% agreement, depending on various polls; versus,
2. Most CC (i.e., more than half) is the result of anthropogenic causes: e.g., 34.6% very much agree, 48.9% agreeing to a large extent; vs. 15.1% to a small extent (2–4), and 1.35% not agreeing at all

It is not true that I have already dismissed Doran & Zimmerman. I'd like WP to include every major poll, as Scientific opinion on climate change currently does, although I don't know why it omits the Oregon Petition.

To NewsAndEventsGuy, I'm not sure what "support my question" means. I'm not asking a rhetorical question, i.e., using the grammatical form of a question to make a point. I have no position on global warming that I'd like this encyclopedia to endorse. It is just the opposite: I want Wikipedia to be neutral about global warming - including the anthropogenic global warming theory - merely reporting fairly every significant theory about it. In particular, I'd like us to describe all known or conjectured cause and effect mechanisms, along with evidence which supports or contradicts these.

I'm not satisfied that we've made it sufficiently easy for readers to find scientific rejoinders to the various theories. (Note, however, that I don't want us to endorse or give "validity" to any theory, because IMHO it's not the role of Wikipedia to say that anything is true or not: rather, we should explain why some published author thinks a thing is true or not.)

I don't care how much "prominence" we give to views held by 85% or more of climatoligists, as long as a reader who wants to see the other side can find it readily. We should, of course, make every effort to ensure that we don't mislead readers by the amount of coverage given to minority views; if every other statement must be a reminder that only 5% to 15% of scientists disagree with the UNIPCC, so be it. It actually is not editorially difficult to clue in the reader about (1) existence of disagreement with the mainstream and (2) the relative smallness of this disagreement. --Uncle Ed (talk) 12:18, 7 June 2011 (UTC)

Oregon petition! Why didn't you SAY so in the first place? See http://www.skepticalscience.com/the-oregon-petition-how-many-scientists-does-it-take-to-change-a-consensus.html NewsAndEventsGuy (talk) 13:02, 7 June 2011 (UTC)

I signed the Oregon petition, and I still stand by my signature, for a different reason, but neither the petition nor the "scientific consensus" is relevant to this article. Although Ed is a bit of a trouble-maker, he's absolutely correct as to what should be in this article. Any significant minority viewpoint (say, held by 5% of scientists) should be mentioned in this article somewhere, and described in detail in this article or a subarticle. — Arthur Rubin (talk) 18:10, 7 June 2011 (UTC)

Arthur, as indicated above the figure seems to be about 3% of scientists publishing in the field: that looks pretty much like a tiny minority that shouldn't be given undue weight. Adding to that, the 3% don't all share the same objections, making it an even tinier minority set of views. So, significance to the topic has to be established before such views are added to this main article: if they're well covered by reliable third party sources we can have [sub]articles about these views, which of course must show them in the context of majority scientific views on the topic. Also, don't expert coverage of the views of scientists who have no established expertise on the topic. There's a whole political aspect which needs improved coverage on Wikipedia, but that doesn't mean giving it undue coverage in an overview of the science. . . dave souza, talk 18:29, 7 June 2011 (UTC)

Not quite. You're conflating different questions. The 3% are those that do not believe that anthropogenic effects are a significant contributing factor in global warming; even the IPCC "consensus" report notes only that it's likely that the majority of [recent] global warming is due to anthropogenic causes. There are probably a number of theories about other contributing factors, some of which should be noted. Also, a number of scientists have noted that the CO₂ should account for double the observed global warming, suggesting an error in the theories. If we can find a source noting that, it should be here, as well as in the appropriate subarticles. — Arthur Rubin (talk) 18:54, 7 June 2011 (UTC)

Professor or Dr Rubin, hello. Borrowing your words, it's hard to discuss article improvements based on "a number of theories about other contributing factors" that "probably" exist. In this entire subsection the only specific reference is to the Oregon Petition. Is there something specific you have in mind? NewsAndEventsGuy (talk) 19:02, 7 June 2011 (UTC)

Actually, I don't have specifics in mind, except for the one I mentioned: I like anthropogenic methane (e.g.., from domestic cattle) (or perhaps other things coming from the back end of a cow) as an alternative theory, but I don't think anyone has analyzed it. — Arthur Rubin (talk) 19:40, 7 June 2011 (UTC)

• Re methane, do you mean the "theory" covered in the Greenhouse gases section, "Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO₂, methane,..." which is referenced to the EPA but I think you'll also find that the AR4 covers this theory in considerable detail. Something to ruminate over. As for the one you mentioned, did you have this in mind? Looks rather fringe.... dave souza, talk 20:07, 7 June 2011 (UTC)
• You might want to check [20] and Attribution of recent climate change#Livestock_and_land_use and maybe even [21]. This is a bit like me claiming "I like to think that satisfiability of first order formulas might be answered by looking only for ground term models, but I don't think anyone has analyzed it"... --Stephan Schulz (talk) 20:14, 7 June 2011 (UTC)

Are you talking about the methane which is discussed here, here, and the last paragraph here, and which is included in nearly all CGCMs? Do you have references explaining why you "like methane" in this context? Anthropogenic methane is pretty well understood. - Parejkoj (talk) 20:27, 7 June 2011 (UTC)

Mibbe Arthur jist likes kye? Or has a steak in it.. <ducks> . . dave souza, talk 20:38, 7 June 2011 (UTC)

Feedback, models, and "emergent properties"

As I understand it, IPCC 2007 used a simple model for A1FI that did not, to use some lay speak, "include" certain feedbacks. But other models used for other scenarios did "include" feedbacks. As a non-modeller, what I get from that is that some models are programmed with the assumption feedbacks can happen, and others are not. Since I'm not a modeller, I'm having some trouble with this sentence,

"Positive and negative feedbacks are not imposed as assumptions in the models, but are instead emergent properties that result from the interactions of basic dynamical and thermodynamic processes."

Its my guess other readers who know the models don't always "include" feedbacks might experience the same problem so I'm hoping some text will emerge from this discussion to help those other readers. Thanks in advance for comments. NewsAndEventsGuy (talk) 11:02, 5 June 2011 (UTC)

The A1FI scenario was run by the same models as ran the other scenarios, and included the same feedbacks. (More correctly, they included the same physical processes that allowed the feedback to be produced.) Short Brigade Harvester Boris (talk) 13:17, 5 June 2011 (UTC)

I'm a newbie, so I'm probably just not seeing the obvious. Me being an amateur, your reply sounds inconsistent with the following quote from Betts, etal (2011) Global_warming#cite_note-Betts2007-8 which reads at pg 68:

The IPCC WGI assessed climate change under these scenarios from a large number of different climate models of varying levels of complexity, including ocean–atmosphere general circulation models (GCMs) and simple climate models (SCMs), with some models also including feedbacks between climate change and the carbon cycle. * * *

Although the six scenarios were all considered by the IPCC to be equally sound as representations of a world that does not implement policies specifically to mitigate climate change [1], not all the scenarios were examined to the same depth with climate models. Practical reasons, such as computational costs, meant that only a subset of the scenarios (A1B, A2 and B1) could be systematically examined with complex ocean–atmosphere GCMs from all the participating modelling groups.1 SCMs were then used to estimate the warming that would have been projected by the complex models under the other scenarios (B2, A1T, and A1FI). Consequently, in the AR4, the highest emissions scenario (A1FI) was examined only with SCMs and not directly with complex ocean–atmosphere GCMs [4].

Help please? It's confusing. NewsAndEventsGuy (talk) 18:24, 5 June 2011 (UTC)

You appear to be seeking expert help. Expert participation on Wikipedia is discouraged by the Wikipedia:Randy in Boise effect, as in this unfortunate instance. Please wait patiently until abnormally knowledgeable service is resumed, do not make ill informed edits to articles. Thank you for your custom, Share and Enjoy. . . dave souza, talk 18:53, 5 June 2011 (UTC)

NAEG is right about this one. I was thinking of A1B, not A1FI. Short Brigade Harvester Boris (talk) 19:40, 5 June 2011 (UTC)

OK, so here's my problem with the text I quoted at the top of this subsection. "Feedback X" does not necessarily emerge from every single model. Sometimes it does, sometimes it doesn't. The phrasing as it now exists is prone to misinterpretation that all feedbacks always emerge from all models, or an alternative false reading would be that if a feedback emerges it was a happy accident, not the result of sweat and brains and some assumptions about what to do in order to create a desired feedback. Moreover, here's this unsupported assertion from climate sensitivity

For a coupled atmosphere-ocean global climate model the climate sensitivity is an emergent property: it is not a model parameter, but rather a result of a combination of model physics and parameters. By contrast, simpler energy-balance models may have climate sensitivity as an explicit paramter.

Before I try to draft alternative text for the following, anyone have any more input on this?

"Positive and negative feedbacks are not imposed as assumptions in the models, but are instead emergent properties that result from the interactions of basic dynamical and thermodynamic processes."

Thanks for reading.... NewsAndEventsGuy (talk) 23:42, 5 June 2011 (UTC)

Neutrality of introduction

I've added tags to this section of the introduction:

Using computer models of the climate system based on six greenhouse-gas emission scenarios, the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) projected that global surface temperature is likely to rise 1.1 to 6.4 °C (2.0 to 11.5 °F) by 2100,[7][8] and the upper limit of that range does not include any warming from the potential release of certain carbon cycle feedbacks.[9][neutrality] By 2010, more recent observations of emissions made the A1FI scenario the "business as usual" case[10], and confirmed that "the worst-case IPCC scenario trajectories or even worse are being realised".[11][neutrality] Recent research suggests that including some carbon cycle feedbacks would result in a temperature rise of 4°C in the 2070's.[9][neutrality]

I'll explain each tag separately below: [Enescot (talk) 01:32, 6 June 2011 (UTC)]

And I have removed those tags. Please discuss prior to tagging — we have been down this "POV" path plenty of times before, so "bold" is getting rather tedious; you really need to make the case first. - J. Johnson (JJ) (talk) 20:23, 6 June 2011 (UTC)

Enescot's neutrality challenge #1

Using computer models of the climate system based on six greenhouse-gas emission scenarios, the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) projected that global surface temperature is likely to rise 1.1 to 6.4 °C (2.0 to 11.5 °F) by 2100,[7][8] and the upper limit of that range does not include any warming from the potential release of certain carbon cycle feedbacks.[9][neutrality]

The statement in bold is based on one paper. This is unbalanced. There are lots and lots of papers on climate change projections, and in my view, citing the results of one paper in the introduction is not acceptable. The article should represent, in a balanced and objective manner, all of the scientific literature. Individual findings or papers should not receive undue weight. It may be appropriate to cite the paper in a sub-article, e.g., the global climate model article. Even then, however, it may still not be appropriate for the reason that I've already given. [Enescot (talk) 01:32, 6 June 2011 (UTC)]

The statement in bold is a statement of objective historic fact. How many papers does it take? Alternatively, can you provide a citation that challenges the bolded text by claiming IPCC has a model that is a perfect representation of the entire climate system? Doubtful, but anything's possible I suppose. Please share it! Meanwhile, the fact remains that none of the models used by IPCC - or anyone as far as I know - have modeled climate sensitivity incorporating feedbacks from the permafrost cycle. NewsAndEventsGuy (talk) 02:08, 7 June 2011 (UTC)

Besides Betts (2011), which you rejected even though it plainly states the historic fact that A1FI didn't include GCMs, please see

This Isaksen, Ivar S. A. (April 20, 2011). "Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions" (PDF). Global Biogeochemical Cycles: 166. doi:10.1029/2010GB003845. The thaw and decay of even a small portion of the permafrost carbon could have substantial effects on atmospheric CO2 and methane concentrations. However, none of the climate projections in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, none of the recent permafrost projections, and none of the projections of the terrestrial carbon cycle account for the PCF (permafrost carbon feedback). {{cite journal}}: Text "Vol 25" ignored (help)

and this Michael R. Raupach, Nicolas Gruber, and Josep G. Canadell (2009). Synthesis Report, Climate Change: Global Risks, Challenges & Decisions Conference, Copenhagen March 2009. The Global Carbon Cycle, Box 2: IARU International Scientific Congress. p. 11. Pools of concern include tropical peatland carbon, which is vulnerable to land clearing and drainage, and the large stores of organic carbon in Arctic permafrost, which are vulnerable to warming. Recent work is starting to quantify the amplifying effect of these vulnerabilities on climate change. There is increasing confidence that their net result will be to amplify the atmospheric CO2 and methane increases to 2100, thence amplifying climate change. The amplification factor is ill constrained, and best current estimates range from near zero to over 50%. Under the IPCC1 A2 emissions scenario, which predicts global warming of about 4C without carbon-climate feedbacks, an additional 0.1 to 1.5C is predicted from the vulnerability of land and ocean sinks. The additional effect of accelerated methane and CO2 emissions from thawing permafrost is potentially very significant but is not yet quantified.{{cite book}}: CS1 maint: location (link) CS1 maint: multiple names: authors list (link)

and this! feedback section of Warren 2011 at http://rsta.royalsocietypublishing.org/content/369/1934/217.full.pdf+html

I like your addition to attribution, so I'm not picking on you personally at all. Taking issues one by one on merits, may I please put that text back now? NewsAndEventsGuy (talk) 13:45, 7 June 2011 (UTC)

Enescot's neutrality challenge #2

By 2010, more recent observations of emissions made the A1FI scenario the "business as usual" case[10], and confirmed that "the worst-case IPCC scenario trajectories or even worse are being realised".[11][neutrality]

This sentence is misleading and lacks objectivity. The A1FI scenario projects future social and economic developments and related emissions over the course of the entire 21st century. A few years of emissions data does not make it the "BAU" case, since future emissions are uncertain. In other words, future emissions trajectories may be above or below the A1FI trajectory. The sentence is supported by two cited sources, however, these sources are not representative of the scientific literature. For example, a USGCRP report (PDF, pp22-23) states that:

Recent carbon dioxide emissions are, in fact, above the highest emissions scenario developed by the IPCC (...). Whether this will continue is uncertain. [Enescot (talk) 01:32, 6 June 2011 (UTC)]

Thanks! I will certainly include that. NewsAndEventsGuy (talk) 02:20, 7 June 2011 (UTC)

A UNEP study (PDF, p55) states:

The majority of results in this report show that emissions in 2020 expected from the Copenhagen Accord pledges are higher than emission levels consistent with a “medium” or “likely” chance of staying below 2° C and 1.5° C. At the same time they also show that the range of 2020 emission levels from the Copenhagen Accord pledges tends to be consistent with the IAM pathways that have “likely” temperature increases of 2.5° C to 5° C up to the end of the twenty-first century. [Enescot (talk) 01:32, 6 June 2011 (UTC)]

Except Copenhagen accords aren't binding on everybody, so that's irrelevant NewsAndEventsGuy (talk) 02:20, 7 June 2011 (UTC)

These two sources support my argument that future emissions are uncertain, and depend on future social and economic development.

It is misleading to suggest that the A1FI scenario is now the "business-as-usual" emissions pathway for this reason. Even though this assertion is supported by two sources, these sources are not representative of the literature. When referring to "BAU" projections, it should be mentioned how wide the range of possible emissions pathways is in the published literature [22]. [Enescot (talk) 01:32, 6 June 2011 (UTC)]

Objection Your Honor, on grounds of speculation! The verbs in the challenged phrase are past and present tense. The upshot of your complaint is that humans <und>might</und> reduce emissions in the future. Well, that's certainly to be hoped for, but not what's happening, as your own supporting reference states! NewsAndEventsGuy (talk) 02:20, 7 June 2011 (UTC)

UPDATE - It's easy to say "these sources are not representative of the literature" but you should support such assertions. Meanwhile please bear in mind that "FI" in A1FI stands for "Fossilfuel Intensive" (Betts 2011) and here is yet another source describing A1FI as BAU (internal cites omitted, emphasis supplied) New, Mark (2011). "Four degrees and beyond: the potential for a global temperature increase of four degrees (Celsius) and and its implications". Phil. Trans. R. Soc. A. 369: 6–19. doi:10.1098/rsta.2010.0303. Even with strong political will, the chances of shifting the global energy system fast enough to avoid 2C are slim. Trajectories that result in eventual temperature rises of 3C or 4C are much more likely, and the implications of these larger temperature changes require serious consideration. In this issue, Betts et al. use a series of global climate model simulations, accounting for uncertainty in key atmospheric and coupled-carbon-cycle feedbacks on climate, to explore the timings of climate change under a high-end, roughly business-as-usual scenario, IPCC SRES A1FI, where emissions have reached 30 Gt of CO2 (8 GtC) per year by 2100. All but two of the models reach 4C before the end of the twenty-first century, with the most sensitive model reaching 4C by 2061, a warming rate of 0.5C per decade. All the models warm by 2C between 2045 and 2060. This supports the message that an early peak and departure from a business-as-usual emissions pathway are essential if a maximum temperature below 4C is to be avoided with any degree of certainty. {{cite journal}}: |access-date= requires |url= (help); Check date values in: |accessdate= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help) NewsAndEventsGuy (talk) 11:53, 7 June 2011 (UTC)

In addition the sentence states:

By 2010, more recent observations of emissions made the A1FI scenario the "business as usual" case[10], and confirmed that "the worst-case IPCC scenario trajectories or even worse are being realised".[11][neutrality]

"Worst-case" lacks of objectivity. The IPCC do not refer to A1FI as the "worst-case" scenario. It is a value judgement made by the authors of the cited source. The only consensus I'm aware of on predominately adverse effects at higher levels of warming is by the IPCC, (Table SPM-3) but this does not specifically refer to the A1FI scenario. [Enescot (talk) 01:32, 6 June 2011 (UTC)]

And heck I can even provide something on this in a day or 3. NewsAndEventsGuy (talk) 02:20, 7 June 2011 (UTC)

Enescot's neutrality challenge #3

Recent research suggests that including some carbon cycle feedbacks would result in a temperature rise of 4°C in the 2070's.[9][neutrality]

This is biased for the same reason I gave earlier. The article should give a balanced overview of the literature, and not place undue weight on the findings of one paper. Enescot (talk) 01:32, 6 June 2011 (UTC)

I'd be happy to review any other papers that have subjected A1FI to a complex GCM model. Has anyone else done it? If not, then one paper IS the literature and keeping it out is to suppress a seminal work that advances the best science we have... so far. Please provide a cite to someone ELSE that's examined A1FI with a complex GCM model, or let me restore the text. NewsAndEventsGuy (talk) 13:51, 7 June 2011 (UTC)

Atmoz' neutrality challenge (by deletion) of Betts study

To explain this edit: I just browsed Betts 2011 and I think that what is cited is at odds with what is written in the actual paper. From what I read, Betts 2011 looked at the A1FI scenario and speculated on the feedback stuff. The ORNI cite is poor, and the other is a press release (therefore poor). So I agree with Enescot and have removed it. I think that something like this could be added to the article (and possibly lede), but with significant editing. -Atmoz (talk) 00:16, 7 June 2011 (UTC)

Insufficient argument, so I restored it. I assume you already know that IPCC only ran the simple (not GCM) model on A1FI and it won't be necessary to prove that by citation, but if you insist you can be obliged. If you do more than browse Betts' paper, you'll see they got access to the necessary computing power to subject A1FI to some of the complex models that employ GCM. That's not mere speculation, that's simply doing what IPCC 2007 AR4 did for the A1B series, only doing it to the A1FI scenario too. You can say they were merely speculating instead of extending IPCC 2007's tools to the highest emission scenario, but hopefully you can provide some basis other than handwaving, which is what I'm hearing right now. NewsAndEventsGuy (talk) 01:52, 7 June 2011 (UTC)

See WP:BRD. And don't refactor other people's comments on talk pages. -Atmoz (talk) 03:24, 7 June 2011 (UTC)

Thanks, since I'm a new editor that was important info for me. NewsAndEventsGuy (talk) 05:03, 7 June 2011 (UTC)

Why not?NewsAndEventsGuy (talk) 05:03, 7 June 2011 (UTC)

On merits of your challenge, the only response I see from you to my comment above is on the one line description for your change in the article version history "dumbassery". Are we waiting for other editors to chime in, or do you plan to say substantive something on the merits?NewsAndEventsGuy (talk) 05:03, 7 June 2011 (UTC)

UPDATE: You agreed with Enscot, but he made three different complaints. Please see my updates to his complaints #1 and #2. Is there still disagreement or can I restore text? NewsAndEventsGuy (talk) 13:48, 7 June 2011 (UTC)

Don't refactor other peoples comments. See the warning on your talk page. This is an encyclopedia. We don't give too much weight individual papers. We try to use the best review papers (in this case the IPCC). Individual studies will differ from the scientific consensus. Our job is not to force one point of view on the viewers as you edits have done. We are trying to provide a neutral overview of the topic of global warming. As Enscot says above, your version did not do that. And I agreed with him/her. As I said, this material may be appropriate in the body of the article, but I don't think it is significant enough for the lede. -Atmoz (talk) 17:11, 7 June 2011 (UTC)

Thanks for calling my attention to the bad practices page, which it turns out, supports what I did. See my User_talk:NewsAndEventsGuy#About_my_re-sectioning_a_talk_discussion_on_article_for_global_warmingNewsAndEventsGuy (talk) 18:38, 7 June 2011 (UTC)

So, you're saying wiki editors have a personal desire to keep the encylopedia locked in a static hovering pattern as science marches forward, right? And to do this, you're apparently relying solely on the IPCC 2007 Synthesis Report because that's where the likely range (without qualifiers) appears, and therefore we wiki editors are perpetuating the statement that there is a likely low end of 1-point-something, but we're not allowed to say up front that that means massive changes like the scientists said in the FULL report? And you're saying that 2007 synthesis report based on even older data is the balanced state of the science, most representative of the best science we have today in June 2011. OK.... please consider analogy #1 -

Doctor to Man --- Well the good news is that if you quit your 2 pack a day habit, give up the 4egg daily omlette, the super size daily burger lunches, quit drinking a fifth a day, and start walking 30 minutes each day you have a decent chance of enjoying another ten good years.

Later that day Man to Wife --- Honey! Great News! The doctor says I'm gonna have another ten good years!

You can't say the man told his wife the best medical advice any more than you can say the sythesis report (generated by political appointees) was a scientific statement. Rather, it was a political statement about a scientific one (the full reports by the three working groups). The latter defines the various likely temperature ranges, with qualification for what we'd have to do to hit the low end. The political appointees left that out, creating the false impression that doing BUSINESS AS USUAL we might only have 1-point-something of warming, and that's not what the full report says. So you're not really defending the balanced view that most represents the literature here.

In addition, if I have persuaded a consensus of editors to look instead to the full report, then we go on to analogy #2 -

Doctor to man - well, we did a full tox panel, and a thorough c-scan. We don't see any evidence of brain cancer but to be sure we'd have to do an MRI only your insurance won't pay for it and the machine is busy anyway. So instead we did the simple type of examine where we look at your sinuses, mouth, ears, and bumps on your head for obvious signs of growth its possible you're ok.

Later, man to wife -- Honey good news! The doctor says I don't have brain cancer!

However, the man's wife knows a neurologist at a rural hospital with the equipment and long quiet nights. Together they sedate the man and just do the MRI. Next day they show him the films and inform him he has TERMINAL but OPERABLE cancer if he acts NOW.

Man to wife and neurologist -- No way, the first dude gave me the best medical advice available.

If you think the man was nuts, then please tell me why you're championing a static political statement about 2007 scientific results based on even older data that wasn't subjected to the full range of testing performed by Betts 2011? NewsAndEventsGuy (talk) 18:38, 7 June 2011 (UTC)

Don't put words in my mouth. Your analogies are pointless, stupid, and have nothing to do with anything. Oh, and don't edit my comments. -Atmoz (talk) 00:06, 8 June 2011 (UTC)

Sorry, I didn't realize inline interspersing was still considered modifying. The folks I exchange complex documents with do it inline, I thought everyone did it that way.

On the merits, it seems I was confused, the AR4 synthesis report (what I characterized as the political above) did qualify the temp range by scenario, even in its top level summary, but the most important section of this article (the Lede) omits that crucial info... because you deleted it from one of my recent edits! All the more reason why my analogy #1 applies. I will demonstrate this with text in a day or two, and you still haven't said anything about my response about Betts 2011 except to insult me. It won't be long before I take that as a green light to put it back. Are you going to reply on the merits? NewsAndEventsGuy (talk) 02:10, 8 June 2011 (UTC)

This comment once again addresses this edit. I had another perusal of Betts 2011 and I still think you're interpreting it wrong. Betts basically took the A1FI scenario and ran it through a full GCM. They found that the best estimate of warming by 2090 would be about 5C. This is within the limits of what the IPCC said in 2007 and is in our article (1.1-6.4C). The fact that the IPCC models were not run as full GCMs for the A1FI scenario does not mean that their numbers were somehow wrong. In fact, since the degree of warming from Betts is basically at the upper range of the IPCC, I don't see why we'd need to cite Betts at all, or include the fact that some scenarios (including the highest emissions one) didn't get run through the full GCM. The "fact" that the worst-case IPCC scenario trajectories or even worse are being realised is specifically refuted by Betts 2011. In fact, there's a whole paragraph devoted to it. What Betts does do is provide an estimate of when warming will be 4C greater than pre-industrial times. This was not previously included in our article, but as Betts says this latter projection [of reaching 4C warming by the late 2060s] appears to be consistent with the upper end of the IPCC’s likely range of warming for the A1FI scenario. So of the two facts that I removed cited to Betts, both are entirely consistent with the IPCC and if we decide to include them, they should be written as if they were the consensus view and not an outlier. But I don't see how including them, especially in the lede, would help the average reader gain a better understanding of the topic of global warming. The other sentence removed is just wrong, whether it's cited or not. If you want to include wrong material in an encyclopedia is your business, but I prefer my reference materials to be accurate. -Atmoz (talk) 15:44, 8 June 2011 (UTC)

Now that's a reply on the merits, for which I thank you very much. I'll digest and come back later.NewsAndEventsGuy (talk) 16:02, 8 June 2011 (UTC)

I've written my reply to your comments in the this section rather than the earlier section that contains my criticisms. I've done this because my reply to your comments are, at least in my view, consistent with Atmoz's.

I agree with Atmoz's point that the IPCC reports should be the central basis for this article's content. You are critical of the Summary for Policymakers document, but any political changes to this document have to be accepted by a group of experts. I actually take the complete opposite view to you in regards to the SPM. In my opinion, it is the most important document the IPCC produces. That's the main reason why I'm critical of the changes you have made.

More recent assessments by the US Global Change Research Program (as I have already cited) and US National Research Council [23] appear to be generally consistent with the IPCC's work.

I'm not exactly sure what the procedure is for restoring your edit. I'm still opposed, but if most other editors are satisfied with your work, then I assume you can restore it. Enescot (talk) 02:25, 9 June 2011 (UTC)

Thanks for your reply, E. As I said to Atmoz, the basis of my attack on the SPM was based on my own delusional interpretation of that document and I recanted that part of my pitch. I'm working on a reply that bubbles up from the specific details as I attempted to insert them, to instead address the conceptual ideas they represent. I'll certainly look at the cites in your last comment as I prepare my response. Thanks.... PS Atmoz, I'm rolling over my work in reply to you into this same process also. Thanks for patience. NewsAndEventsGuy (talk) 11:10, 9 June 2011 (UTC)

Careful with sources please

In this edit Dave souza (talk · contribs) sources the statement "the 20th century instrumental temperature record shows a sudden rise in global temperatures", but the sources provided are about Arctic warming, not global warming. I'm not going to revert because I think the text is right, but it needs better sourcing. -Atmoz (talk) 21:16, 9 June 2011 (UTC)

This replaces the unsourced statement "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", and while the research specifically deals with the Arctic, the cited sources discuss the implications for an ice age which by definition extends beyond the Arctic. To meet the concerns about the modern temp record being global, I've added an additional citation, to Mann et al. 2008. While minority views have quibbled about this paper, it's been backed up by more recent research such as which could also be added as a source if desired. . dave souza, talk 00:47, 10 June 2011 (UTC)

Mann08 is good (for me). I was just concerned that someone might come along later and remove the entire sentence because the source didn't specifically backup the statement. Although I suppose that there was a better chance of that when it was unsourced. Anyway, thanks. :) -Atmoz (talk) 21:08, 10 June 2011 (UTC)

No, this sentence is still garbage. Mann08 is based on proxies so cannot be used to justify the claim. Besides, Mann08 has been shown to rubbish by professional statisticians McShane and Wyner, who say the proxies have a weak relation to temperature and are hardly any better than random numbers. See doi:10.1214/10-AOAS398. Poujeaux (talk) 12:00, 16 June 2011 (UTC)

Lede streamlining

The lede has be trimmed considerably, and makes for a more coherent overview, with one exception; Global Warming not only encompasses the current temperature rise, but the projected continuation as well. It isn't until well down in the lede that a higher rise is implied, which I believe results in a sense of vagueness about future expectations. I suggest that we add "and its projected continuation" back to the first sentence to clearly capture the expectations of the scientific consensus. An alternative could also be "...the current and future rise..." or "...the current and continuing rise...". - Skyemoor (talk) 14:44, 15 June 2011 (UTC)

I agree with the change, and sensing no opposition, I added it. Feel free to revert and discuss if you disagree. -Atmoz (talk) 16:09, 15 June 2011 (UTC)