Talk:Effects of climate change/Archive 1

Archive 1

Archive 2

Archive 3

→

Archive 5

Regional breakdown

I recommend a breakdown of potential impacts by region, where possible. It would make it so much more illustrative and relevant to people. Daniel Collins 3 July 2005 21:08 (UTC)

I now see there's an entry on the National Assessment on Climate Change, which is to adddress the US impacts, but it is in need of much attention at this time. Daniel Collins 4 July 2005 15:56 (UTC)

"It is not possible to be certain whether there will be any positive benefits of global warming. What is known is that some significant negative impacts are projected..."

Look this article is so corrupt and ridiculous that there is no saving it. How could you possibly claim that there were negatives. And that you know about them. And you can't predict positives? And all this on top of the ridiculous idea that CO2 can warm us from where we are now rather then mitigate the cooling?????

Is there a scientist in the house? I tell you that no authentic scientist could support this fraud. —The preceding unsigned comment was added by 122.148.183.191 (talk) 08:47:09, August 19, 2007 (UTC)

Shutdown of THC

I've moved a variety of things from various articles gulf stream, thermohaline circulation, north atlantic current about THC shutdown to here, which seems best. The discussion here reflects my interpretation of the IPCC view, which is much less alarming than some of the other text. William M. Connolley 13:54:14, 2005-07-30 (UTC).

"primary symptom"

"The predicted effects of global warming are many and various, both for the environment and for human life. The primary effect (indeed, the primary symptom) of global warming is increasing carbon dioxide and increasing global average temperature. From this flow a variety of secondary effects, including rising sea levels, declining output of global agriculture, increased extreme weather, and the spread of disease. In some cases, the effects may already be being experienced, although it is generally difficult to attribute specific natural phenomena to long-term global warming."

surely the increase in carbon dioxide is the primary cause of climate change? not an effect. if it is a symptom, what is its root cause? while global warming is likely to increase greenhouse gas levels in the atmosphere (methane release), this does not contribute directly to carbon dioxide increase in the atmosphere.

so I feel that the line "The primary effect (indeed, the primary symptom) of global warming is increasing carbon dioxide and increasing global average temperature." sould be reduced to "The primary effect is an increasing global average temperature."

--Naught101 01:41, 25 August 2005 (UTC)

the past forest fire stats since 1970 for North America

the past stats for forest fires for North America cannot be attributed to Global Warming with any credibility. This source attributes them the fuel buildup, and forest ecology change due to past fire suppression practices, plus the increased population in the western US. [1]--Silverback 10:43, 13 September 2005 (UTC)

I've reviewed the new forest fire text, and while it is less hyperbolic, but it is still appears to be an attempt to start a new fear mongering front, and without much scientific basis, and in fact flies in the face current scientific trends in forest management. For instance the phrase about more "regular fires", is apparently intended to be a criticism, while it may well be a benefit, since fire suppression is thought to be responsible for larger more intense and destructive fires. The predictions of impact on forests are more well balanced between benefits and possible negatives than just about any impact that is considered. The reinsertion of the language on positive feedback is intended I think to suggest some kind of dire reunaway process, when forest fires are naturally self limiting, and the most common impact mentioned for global warming is actually more forest growth. --Silverback 07:31, 16 September 2005 (UTC)

The Loop Current Effect

Hurricanes Katrina and Rita both rode the warm Loop Current, but Rita crossed more cold water afterwards. Hurricane Camille probably went the length of the Loop Current and crossed virtually no cold water afterward - and made landfall as a Category 5. So a major question would be: is Global Warming increasing the SST (sea surface temperature) of the Loop Current?

Also, does it seem like hurricane tracks are more northwards than before? The more northward a track, the more likely the hurricane is to ride the Loop Current.

Simesa 13:28, 25 September 2005 (UTC)

When examining "more", consider the size of your sample. If you're examining an average, it is nice to have hundreds or thousands of measurements. How many thousands of hurricanes each year are you measuring? (SEWilco 13:54, 25 September 2005 (UTC))

A paper is coming from Dr. Kevin Trenberth on the topic of Loop Current water temperature and hurricane strength. Loop Current temperature in the Gulf of Mexico is directly measured by NOAA buoy #42003 [2]. Part of this is in [3] Simesa 23:12, 1 December 2005 (UTC)

Any idea whether/how to incorporate this on the effects of less snow on permafrost? Rd232 ^talk 14:45, 8 December 2005 (UTC)

Cost of extreme weather events graph

(from Talk:Global_warming#Image:Cost-of-storms-by-decade.gif -- please see)

An extrapolation is not simply a way of displaying data. It is predicting beyond the data. A prediction like this is either original research or a simple pipe-dream, unless it has been published in a peer reviewed source it is out. Out from this article and any article. So, where has this extrapolation been published? Vsmith 04:16, 24 December 2005 (UTC)

I disagree. Extrapolation bars and curves are commonly referred to as "chart decorations" by graphic designers. They do suggest a prediction, which is what they are supposed to do, but they strictly reflect only the underlying data upon which they are based. The practice of printing extrapolations with historical data is commonplace in news, almanac, encyclopedia, and many other kinds of publishing, and is never considered original research. The graph is no more original research than if I were to reflect in the text of the article that, for example, "If present trends continue, the cost of extreme weather events could exceed 350 billion inflation-adjusted U.S. dollars per year by 2025." Don't you agree that is better said with a graph which displays the historical statement directly than with that sentence? James P. S. 08:23, 24 December 2005 (UTC)

This excerpt was requested here by Vsmith; please continue discussion at Talk:Global_warming#Image:Cost-of-storms-by-decade.gif.

I've re-rm'd the graph. My objections at GW remain the same; I'll discusss it there. William M. Connolley 09:04, 24 December 2005 (UTC).

Here is the graph, for the record:

I am asking third party climate bloggers to independently comment on it and will report the comments back to Talk:Global_warming#Image:Cost-of-storms-by-decade.gif. I intend to replace the graph here after their review, unless any significant issues are raised. James P. S. 22:17, 24 December 2005 (UTC)

One expert nominated by a graph deletionist has already called the extrapolation reasonable, not implying the cause of the variation, NPOV, and only technically borderline OR. Therefore, I'm replacing it here and on mitigation pending outcome at Climate Change Action and Talk:Global_warming#Image:Cost-of-storms-by-decade.gif. --James S. 18:47, 28 December 2005 (UTC)

Your eagerness to add this graph is starting to shade into disrespect for your fellow editors. Please give sufficient time for agreement to be reached on Talk:global warming, and don't prejudge the outcome of that debate. Thank you. If you want to add the graph straight away, please add a version which contains only the historical data - this would be uncontroversial (I think) and useful to the reader. Rd232 ^talk 00:29, 29 December 2005 (UTC)

Eagerness? I think it is very important information and so far there has been no evidence to the contrary presented. The person who originally removed it from Global warming has been making graphs with selectivly reversed x-axes. Wm. Connolley has agreed with the assessment, produced by a third-party reviewer that he himself suggested, that the extrapolation is reasonable, doesn't imply causes, has a NPOV, and is only borderline original. —James S. 01:09, 29 December 2005 (UTC)

Removed graph per discussion in Talk:Global Warming. Consensus there is that the fit isn't reliable. There is evidence that other fits would be better. Finally, the extrapolation considers no feedback effects nor physical limits - which intuitively should be there. Simesa 10:19, 29 December 2005 (UTC)

Simesa has falsely represented the clear consensus that the extrapolation is reasonable, does not imply information about the cause of the variation, has a NPOV, and is only borderline original. I invite anyone to see Talk:Global_warming#Image:Cost-of-storms-by-decade.gif for themselves, and I ask Simesa why he or she has made such a false representation:

Moreover, I dispue the claim that other fits would be better. I have several fits to the data. What evidence does Simesa have to support that any fit is better than another? What evidence does Simesa have that feedback systems can not be modeled with linear, transcendental, or combined non-linear models such as the 2nd and 3rd revision of the graph? —James S. 22:33, 29 December 2005 (UTC)

In Talk:Global Warming the following editors are critical of putting the graph in: Dragons flight, Guettarda, Rd232, NHSavage, Kmf164, Anastrophe, William M. Connolley, Stephan Schulz, Vsmith, bikeable and myself. Only one is in favor - you.

Simesa 01:55, 30 December 2005 (UTC)

I am not sure which graph that vote is referring to; I voted with those editors to exclude the first revision. Are you sure you are representing the vote correctly? —James S. 03:28, 30 December 2005 (UTC)

You make my point - what says that an exponential or low-order polynomial fit is adequate? Intuitively, there's a maximum to the damage simply because there's a maximum to the number of storms.

Simesa 01:55, 30 December 2005 (UTC)

Are you familiar with the process of regresion? The equations chosen were selected because they had the least sum-of-squares error, as measured by adjusting by the number of parameters and adjusted degrees of freedom. Do you have any evidence that a more poorly-fitting model would be a better prediction? Your intuition may be misleading you. Average storm strength is a function of the average wind speed (laminar and turbulent kinetic energy) in the 3D field, which is proportional to atmospheric energy over temperature (localized molecular kinetic energy.) Do you believe that there is a maximum global average windspeed? If so, what do you beleve it is? Do you believe the current global average windspeed is anywhere near it? —James S. 03:28, 30 December 2005 (UTC)

Yes, I am highly familiar with regression, having had several years of college math beyond calculus plus engineering. But it isn't the tightness of fit to pre-2001 data that's the question (although a higher-order polynomial would be better), it's the plausibility of the extrapolation when limits may come into play. The originator of the Saffir-Simpson scale said:

"When you get up into winds in excess of 155 mph you have enough damage," Simpson said in a 1999 interview with the National Weather Log, a publication of the National Oceanic and Atmospheric Administration. "If that extreme wind sustains itself for as much as six seconds on a building it's going to cause rupturing damages that are serious no matter how well it's engineered. So I think that it's immaterial what will happen with winds stronger than 156 miles per hour. That's the reason why we didn't try to go any higher than that," Simpson said.

Simesa 09:30, 30 December 2005 (UTC)

Based on reports of $200 billion in 2005, the above graph based on the same data ending in 1998 predicts the 2005 results more accurately. It also has a wider confidence interval, addressing many of the objections to the other graphs. —James S. 20:48, 1 January 2006 (UTC)

There still has to be physical significance behind the projections. Yes, 2005 fits because New Orleans was hit (and because it was uniquely low-lying) and the Gulf Coast was hit by both Katrina and Rita. But you're predicting three times that much new damage every year by 2010? Thirteen times that every year by 2020? That would be around 90 city hits through 2020 - not only would we expect people to learn from these, but these cease to be independent (that is, we should expect cities to start being hit more than once), invalidating one of your assumptions. Simesa 08:58, 14 January 2006 (UTC)

Proportion of extreme weather costs attributable to global warming

{{reqdiagram}}

Does anyone have any good sources on this? —James S. 08:28, 3 January 2006 (UTC)

I suggest browsing the IPCC report, and Roger Pielke's blog http://sciencepolicy.colorado.edu/prometheus/. There's lots of good stuff there that you won't like (I often don't). For example this: http://sciencepolicy.colorado.edu/prometheus/archives/disasters/000653exchange_in_todays_.html William M. Connolley 10:39, 3 January 2006 (UTC).

Great stuff! The citation by Evan Mills of this work and Choi & Fisher in Clim. Change 58, 149 (2003) seems to be the best quantifications. —James S. 22:43, 3 January 2006 (UTC)

Reducing carbon dioxide emissions from a high to a low scenario would reduce the impact on losses and insurers’ capital requirements for extreme windstorms by 80%. Action to reduce society’s vulnerability to some inevitable impacts of climate change, for example through more resilient buildings and improved flood defences, could also result in considerable, but targeted, cost-savings.[4]

"[A] 1% increase in annual precipitation would enlarge catastrophe loss by as much as 2.8%." -- Choi, O. and A. Fisher, "The Impacts of Socioeconomic Development and Climate Change on Severe Weather Catastrophe Losses: Mid-Atlantic Region (MAR) and the U.S." Clim. Change 58, 149 (2003.) —James S. 20:01, 7 January 2006 (UTC)

Thats all very well, but it says *would* not *has*; nor does it predict such an increase. William M. Connolley 20:35, 7 January 2006 (UTC).

What? That is their derivation from historical data. Have you read the article? —James S. 20:41, 7 January 2006 (UTC)

Also http://www.bom.gov.au/info/CAS-statement.pdf may be useful. The rapid increase of economic damage and disruption by tropical cyclones has been caused, to a large extent, by increasing coastal populations, by increasing insured values in coastal areas and, perhaps, a rising sensitivity of modern societies to disruptions of infrastructure. William M. Connolley 20:28, 26 February 2006 (UTC)

Extreme weather and stuff - needs work

This page needs some work done on the reasons and the extreme weather. It needs better sourcing from scientific papers and rather less from New Scientist and stuff. In my opinion the primary source should still be the IPCC TAR, updated (if you've got it...) by the AR4 drafts, and various papers (e.g. Emanuel) since then. I've made a start. This table [5] (and the real sources in the other chapters) is useful.

I've removed (sorry) this:

The radiative forcing which causes global warming also leads to increases of average global wind speed. Because, at higher temperatures more water is evaporated and transpires, leading to increased precipitation, which in turn adds greater amounts of kinetic laminar and turbulent mechanical energy, or wind.

which is simply garbled. If there is evidence for increases in wind speed from observations or future modelling, please show it. The TAR table I ref'd refers to likely future increases in cyclone speeds but not global wind speeds. The atmosphere is complex: more radiative forcing equals more wind speed is simplistic. increased precipitation, which in turn adds greater amounts of Kinetic energy is simply wrong: increased ppn doesn't of itself do much to wind speed at all. http://www.antarctica.ac.uk/met/wmc/zonm-u-ghg3-2030-2070.png, for example, shows zonal mean windspeeds for 2030-2050 avg and 2070-2090 avg - care to guess which is the red line and which the blue?

William M. Connolley 11:10, 3 January 2006 (UTC)

Evaporation happens at the molecular level due to brownian motion, and precipitation occurs in large particles with accumulated potential energy falling. The drafts in a rainstorm are well understood. Is there any evidence that the water cycle doesn't convert thermal energy to mechanical wind? —James S. 22:54, 3 January 2006 (UTC)

Of course, now that I think about it, most wind comes from differences in barometric pressure. Obviously that must have a thermal source due to the lack of giant air compressors and giant vacuum hoses in the sky. But what is the proper scientific way to describe the causal chain from thermal power to pressure changes? Volume expansion of heated air? —James S. 22:57, 3 January 2006 (UTC)

Methane hydrates?

The section on the oceans is possibly missing something about methane hydrate release. As I understand it, these will be destabilised by warmer, less dense waters above them. I think I'm right in saying that this is believed to be at least partly responsible for the Paleocene-Eocene event. Shall I add something? It's not my specialist subject. --Plumbago 17:56, 4 January 2006 (UTC)

This was just brought up in an environmentalist YAHOO group, but the links there were poor. I'd like to see something on it. See Methane clathrate [6] [7] [8] and passworded [9]. Simesa 23:57, 16 May 2006 (UTC)

Change to More Extreme Weather

I made the following changes:

"The Intergovernmental Panel on Climate Change (IPCC) third annual assessment report stated "there is no compelling evidence to indicate that the characteristics of tropical and extratropical storms have changed." [1] There is, however, limited evidence from a relatively short time period that storm strength is increasing..."--Smithsmith 20:02, 28 January 2006 (UTC)

Its always nice to see people using IPCC as their authority. Some skeptics even seem to dislike it: how odd! Be aware that the AR4 is nearly due, though, and storm frequency has been an active topic recently. William M. Connolley 20:10, 28 January 2006 (UTC).

I would also make a humble appeal that the reference to the Time Magazine article be deleted. This magazine is a popular news and special interest magazine, not a scientic journal. Also the reference to the The Independent under "Decline of Agriculture" section in my humble opinion should be deleted.--Smithsmith 20:37, 28 January 2006 (UTC)

Kevin E. Trenberth's new letter is out [10]. I think the two most salient quotes are "It should be recognized that the issue is not black or white, but rather that global warming has a pervasive influence on ocean SST [sea surface temperature] and heat content, atmospheric temperature, water vapor, and atmospheric and oceanic general circulation patterns, all of which affect tropical cyclones in complex, not yet fully understood ways." and "in our view the growing body of evidence suggests a direct and growing trend in several important aspects of tropical cyclones, such as intensity, rainfall, and sea level, all of which can be attributed to global warming." In sum, the NCAR and others believe a lot more study is needed very fast. (This is already treated in the article.) Simesa 21:14, 5 May 2006 (UTC)

Negative versus positive

Is the purpose of this page to only talk about the negative effects of global warming (i.e. change title to "Negative effects of global warming")? For sure the negative effects may outweigh the positives and maybe some would say there are no positives, although this seems unlikely. I thought that with warmer temperatures and more rain there had been speculations about longer growing season's, etc, and extra carbon dioxide having a fertilizing affect (more food to feed the world). Maybe that is too minor to mention. Anyways at the moment this page looks very one-sided, although maybe that is the way it really is (although in life only good effects or only bad effects from any change is rare I would say). Anyways, just my two cents. Delete this at will ;-) Ian Schumacher 01:01, 1 February 2006 (UTC)

To add to this, haven't some models predicted more stable weather?Ian Schumacher 01:05, 1 February 2006 (UTC)

I believe you are right, Ian. There seems to be a lot of people who want to make sure we are sufficiently alarmed on the matter of global warming. It is what others call the "Chicken Little Effect", and it states that "the likelihood of public funding for a project is directly proportional to the degree of misery perceived by doing nothing." It is only natural that climate scientists would be biased toward pushing the misery option. --Smithsmith 03:13, 2 February 2006 (UTC)

Thank you for making your own biases clear. William M. Connolley 09:52, 2 February 2006 (UTC).

It's clear that there will be both positive and negative effects to global warming. The problem is that humanity and civilization don't work just as an aggregate. Some segments of the world will benefit from the positive effects and other segments will suffer from the negative effects. Unless you propose to tax the segments that benefit to alleviate the pain of those who suffer from the negative effects, it is useless to talk about whether the balance is net positive, neutral or net negative (unless, of course, you can prove that the net difference is certain to be so large as to mandate favoring or opposing global warming).

If we don't know the magnitude of the positive and negative effects, then we are better off being conservative and mitigating the pace of global warming so as not to run willy-nilly off a cliff whose height we are unsure of.

If we become more certain that the positive effects are outweighing the negative effects, we can always take our foot off the brake and generate more greenhouse gases. It's much harder to pull those greenhouse gases out of the air once they've been generated.

We are also well-advised to plan adaptation strategies to alleviate the suffering of those who will be hit by the negative effects.

The assumption here is that businesses and governments will move quickly to reap the benefit of any positive effects without any prodding or calls for advance planning.

All that having been said, feel free to add in any positive effects that are verifiable. Also feel free to add to the article Adaptation to global warming.

Richard 19:38, 13 April 2006 (UTC)

In regards to Ian Schumacher comments above: "I thought that with warmer temperatures and more rain there had been speculations about longer growing season's,etc, and extra carbon dioxide having a fertilizing affect (more food to feed the world).", yes a longer growing season has been projected in some areas, but this cannot be assumed to be a positive effect because more drought is also projected (the "more rain" projected means larger individual downfalls, but dryer conditions in general due to more heat and less frequent rain). As well, growing seasons are projected to shift Northward, so even if an area gets enough regular rain to take advantage of an extended growing season can this be a net positive given that areas Southward are losing their growing seasons due to increased heat? In regards to the comment about speculation of increased C02 having a fertilizing affect on plants, recent studies of plants near natural C02 emitters show that the protien content of such plants suffers. This is based upon real science occuring in Yellowstone National Park (http://kutv.com/idaho/ID--Yellowstone-CO2_v_n_0id-n/resources_news_html) rather than the speculation of organizations that are involved in special-interest funded PR campaigns rather than science, and have been the main source of the idea that more C02 is better for plants.

recent reverts

The article says:

Increasing temperature is likely to lead to increasing precipitation [11]

And N bumped this up to Increasing temperature is very likely to continue to and I don't know what the evidence is for that. I've added a ref to the SPM which explicitly states the "likely" [12].

I removed, and N re-inserted:

Wind produced from differences in barometric pressure has increased as radiative forcing increases the relative amount of daytime thermal expansion of air, and is also expected to continue to increase.

Curiously, he added the citation-needed bit, which seems to indicate he knows of no source for this. I don't think its true.

Again, N replaced "may" with the bold bit in This has been shown to cause, and is expected to continue to cause heavier rainfall and I'm not sure that is justified.

William M. Connolley 12:43, 25 February 2006 (UTC)

Those changes are completely inconsistent with the rest of the article. Just search for each instance of "precipit" and see how far those edits are from the rest of the article. I inserted the "citation needed" tag to remind me to find a source for that. Is there any question that mean wind speed is increasing? I've read that from multiple sources. I hoped that you had one handy. --James S. 19:29, 26 February 2006 (UTC)

Well please find the citation *first* and add the text after. I know of no evidence that global mean wind speed is increasing, and since you can't find a citation, I don't think you do either. William M. Connolley 20:24, 26 February 2006 (UTC).

Added. --James S. 08:50, 27 February 2006 (UTC)

Removed. Your ref [13] seems completely besides the point. You need to justify steps a,b,c in your (a) wind produced from differences in barometric pressure has increased (b) as radiative forcing increases the relative amount of daytime thermal expansion of air, (b) and is also expected to continue to increase. I don't see your ref as justifying any of them. Kindly quote from it.

Also, I added a nice link to the TAR to justify just "likely"; presumably in order to too feel too embarassed about your "very likely" you removed that, but it doesn't seem very honest. William M. Connolley 21:25, 27 February 2006 (UTC)

I was (a) being too conservative in an abundance of caution, and (b) trying to make all the sections self-consistent. I believe the certainty is easily such that "very likely" should be preferred. --James S. 23:18, 28 February 2006 (UTC)

Will you please stop making this stuff up. You're now down to using deceptive edit summaries - you have simply reverted, restoring all the wind speed nonsense etc. I've pointed out that your so-called ref is simply irrelevant. Please answer to the point. William M. Connolley 23:27, 28 February 2006 (UTC).

What are you accusing me of fabrticating now? What do you have against the first Google hit on "global mean wind speed" [14]? --James S. 00:53, 1 March 2006 (UTC)

Your ref appears to be a satellite calibration study that discusses neither global warming nor long-term changes in wind speed. Maybe I'm missing something, but it does not seem to be relevant to the point you are making. Dragons flight 01:22, 1 March 2006 (UTC)

When I skimmed it I thought it was comparing two data sets from different time periods. Are you saying the two data sets are actually from the same time period? --James S. 02:45, 1 March 2006 (UTC)

Yes, it is a comparison of satellite and ground based observations of the same sites and the same time periods as a check on the accuracy of space based reconstructions of wind patterns. Dragons flight 02:58, 1 March 2006 (UTC)

I read relevant parts of the reference and, now having read the discussion, concur wth WMC and Dragons Flight. (And I'm one of the guys arguing that Global Warming is a massive danger.) Now an increase in Hurricane wind speeds, that's a different matter. A Google search on GW and increase in wind speeds minus hurricanes turned up nothing useful (but see 2.4.4 in [15]). Regarding general wind speeds, I deleted the paragraph. Simesa 06:53, 1 March 2006 (UTC)

Northwest Passage Section

The Northwest Passage section includes this: "While the reduction of summer ice in the Arctic may be a boon to shipping, this same phenomenon threatens the Arctic ecosystem, most notably polar bears which depend on ice floes."

The Sea level change article says in part, "If all glaciers and ice caps melt, the projected rise in sea-level will be around 0.5 m. If the melting includes the Greenland and Antarctic ice sheets (both of which contain ice above sea level), then the rise is a more drastic 68.8 m.[[16]]"

I'll ignore for now the conflict of the last sentence with the graph on the Sea level article (posted by Dragons flight) which suggests that the historical mean sea level is more like 100m higher than currently. (Hmm... where did that extra 30m of water come from? That was a little before Noah's time.)

I'd like to focus on the situation of the polar bear and the arctic ecosystem. Now this article, in saying that polar bears are threatened by GW because they "depend on ice floes", seems to imply that the disappearance of arctic sea ice equals the extinction of the polar bear -- plain and simple, no room for interpretation.

Yet the Sea level change article, providing a citation, asserts that the loss of all "ice caps" excluding the Greenland and Antarctic ice sheets (in other words, the loss of all Arctic and Antarctic sea ice) would raise sea level by about 0.5 m. We all know that such a rise would be a non-event compared to geologic-scale sea-level fluctuations.

Here is a bulletin [[17]] from the University of Tokyo, reporting findings that as recently as 7,600 years ago, the sea level at the Boso Peninsula of central Honshu was 10-11 m higher than now. It also reports the discovery of evidence that during the Neogene, sea level at that location has been as much as 27.5 m higher than currently. (Bivalve boreholes were found in the Neogene siltstone at that level; they are "abundant" up to 25m and "isolated" the rest of the way.) Admittedly, this is authored by a representative of Mobil Oil Canada. It's the first detailed citation I could find for Neogene sea level, and I don't have time to keep looking right now. If anyone can point me to a more appropriate source, I'd appreciate it.

So ... for anyone who cares to defend the sentence on arctic ecology and the polar bear, how do you explain the continued existence of the polar bear over its two-million-year existence, if the geologic record clearly supports that during some of this time sea level has been so high there couldn't have been any sea ice at all?

And how do you explain the continued existence of an arctic ecosystem when the record clearly supports that there have been numerous times in the Neogene when there couldn't have been any sea ice?

In biology the term "threatened" implies that something's existence is threatened. If the arctic ecosystem as we know it today is simply going on hiatus for brief periods, after which it comes roaring back post-haste during cool episodes, was it really ever "threatened"? Perhaps "stressed" is the more appropriate term.

If these questions (polar bear and arctic ecosystem) cannot be explained, then the sentence in the article should read: "... this same phenomenon stresses the Arctic ecosystem, most notably polar bears." (Cutting the words "which depend on ice floes".) -- Fowler Pierre 18:08, 12 April 2006 (UTC)

I know basically nothing about polar bears and their lifestyle requirements, but our article on them says they evolved only about 2 million years. It is widely believed, though I don't know with what degree of certainty, that the Arctic sea ice has been continuously present for at least the last 3 million years, in which case there is no apparent contradiction. The evidence of sea level change from Japan is not representative of the global picture. I would presume this is because Japan is a hugely geologically active nation and local tectonic uplift is dominating the changes. As to your question about higher sea level in the past: Over geologic periods, sea level change is strongly influence by tectonic shifts that affect the depth of ocean basins. If the ocean floor is pushed up then for a fixed volume of water sea level will appear higher from the pont of view of the continents. Dragons flight 18:35, 13 April 2006 (UTC)

After edit conflict ...

Don't know 'bout the polar bears, but, the sea level records for Japan seem most likely to be a record of the local rate of tectonic uplift rather than any worldwide sea level change. I had a reference cited to me on my talk page of a 72 mm/yr rate of uplift for Japan. Seems the Japanese data may be irrelevant to polar bears. Vsmith 18:46, 13 April 2006 (UTC)

The Japanese assertions seem reasonable... I just learned that it's on a subduction zone, which I wasn't certain aout. Can anybody point me in the direction of some info about the belief in sea-ice being present over the last 3 ma, about Neogene sea-level in general, as well as the ocean-basin-depth factor? No need to rush, just whenever. Thanks. And folks ... feel free to tackle the missing 30+ meters of water that I mentioned at the top of my question. I'm dying to know how that happened, and what if anything needs to be done fix that apparent discrepancy.--Fowler Pierre 19:09, 13 April 2006 (UTC)

The basic problem is that polar bears need ice floes as rest stops while they swim and fish for food. [18]

Even if you can show that sea levels were higher eons ago, the reasoning presented earlier in this section about no sea ice assumes that the sea levels were higher due to warmer temperatures. Even granting that assumption, the reasoning further assumes that the disappearance in sea ice happened as rapidly then as it is happening now. If the lack of sea ice long ago was due to natural forcing and the disappearance of sea ice now is due to global warming, you cannot assume that the time frames of change are the same. Polar bears may have been able to adapt to the disappearance and reappearance of sea ice over a long period of time (hundreds or thousands of years?) whereas they may not be able to adapt to the disappearance of sea ice over the course of a few decades. I'm not saying whether they can or they cannot. I'm just pointing out the apples to oranges comparison fallacy in the argument presented above.

Richard 19:51, 13 April 2006 (UTC)

IPCC Third Assessment Report

The article has virtually nothing in it. Would someone knowledgeable want to tackle it, or should we wait for IPCC Fourth Assessment Report? Simesa 19:34, 17 May 2006 (UTC)

Clathrate Gun Hypothesis

This needs expanding also. There's some on it at the bottom of methane clathrate. I've written to NCAR for info. Simesa 17:29, 18 May 2006 (UTC)

My source at NCAR wrote back; it's not his area, and they're swamped with getting ready for the IPCC. The NCAR Newsroom now only takes inquiries from professional journalists. Guess this topic will have to wait for later. Simesa 06:30, 1 July 2006 (UTC)

More murder

Is the paragraph on increased murder rates in the 'health' section very accurate? I find it hard to beleive that murder and temperature can be so closely linked. Tkos 12:08, 2 June 2006 (UTC)

Indeed, severe heat would tend to make people lethargic. Dogru144 05:13, 2 August 2006 (UTC)

I've taken it out. It's a misstatement of a pop-science book interpreting one research paper, with the source given as a review of this book... If someone has the book (Body Heat: Temperature and Life on Earth by Mark S. Blumberg) and can dig out the original reference, I'm ready to take a look at it. I doubt that this relationship has any solid foundation...--Stephan Schulz 06:58, 2 August 2006 (UTC)

While / whilst

From while

"Whilst is synonymous with while in standard British English, although it sounds slightly old-fashioned, and is rare or archaic in American English."

Let's use "while". More people will understand it.

--Richard 20:08, 6 June 2006 (UTC)

No. Going around changing spellings is a Bad Idea. Its pointless and provokes Discontent William M. Connolley 21:19, 6 June 2006 (UTC)

Economic Cosequence

This article is about the effects of global warming, not the damage of global warming. Lack of cost benefit calculation of economic variable appear to favour green perspective. I have inserted one academic reference. Vapour

Temperature Rise

The Temperature Rise section under Oceans does not state how much on average the oceans have warmed over the last century. I found almost 1 degree C over the past 100 years in [19]. Simesa 06:53, 1 July 2006 (UTC)

Ocean Acidification

I inserted a link, but thought excerpts from the story merited inclusion in Discussion: [20]

July 5, 2006 — The same manmade gases that are heating up the planet are also making oceans acidic enough to dissolve the skeletons and shells of many marine organisms, according to a new scientific report released Wednesday.

....

Ocean acidity has already increased 30 percent since the start of the Industrial Revolution in the early 19th century, said Richard Feely, an oceanographer at NOAA's Pacific Marine Environmental Laboratory in Seattle. By the end of the 21st century that could go up to 150 percent, he said."

....

... many affected organisms are also food sources for many commercially important fish – like salmon.

....

The new report is the result of years of work by scientists worldwide and was assembled by top researchers at the US Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the National Science Foundation (NSF), the National Center for Atmospheric Research (NCAR), and universities.

Simesa 13:53, 6 July 2006 (UTC)

Strictly speaking, ocean acidification is unrelated to global warming (except that they're caused ultimately by the same thing). It would happen regardless of the climate effects. Maybe this article is mistitled and "effects of anthropogenic CO2" would allow all of the effects to be in one place? Cheers, --Plumbago 13:58, 6 July 2006 (UTC)

True... but maybe too picky? The CO2 fertilisation is another example, but thats mixed up with plants changing under T/ppn changes anyway William M. Connolley 14:13, 6 July 2006 (UTC)