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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 55301 to 55350:

  1. Climate skeptic claims prebunked by Keeling
    Oh yes, you can see the variability in the MLO record at one of the links above, with a link to where you can download the hourly data, so no Paul, that dog don't hunt neither http://rabett.blogspot.com.au/2009/10/ian-plimer-is-con-artist-one-of.html
  2. Lindzen, Happer, and Cohen Wall Street Journal Rerun
    Dana, You have the patience of Job cranking out all these counters to WSJ crap. Keep up the good work.
  3. Global Warming - A Health Warning
    Sphaerica I'm pretty sure more than 0.6C warming due to GHGs has already been realised.
  4. Lindzen, Happer, and Cohen Wall Street Journal Rerun
    CHL proceed to repeat the grossly oversimplified myth that more CO2 is good for plants:
    "CO2 levels are below the optimum levels for most plants, and there are persuasive arguments that the mild warming and increased agricultural yields from doubling CO2 will be an overall benefit for humanity."
    Given the recent climate impacts on wheat in Russia and corn in the United States, for example, this contrarian argument is a rather large pill to swallow.
    This is an important point, and worth nominating in the form of Sprengel's Law of the Minimum.
  5. New research from last week 33/2012
    Sea level is predicted to rise at least 80cm by 2100 and continues to rise at least 200 years after that
    I'm pleased to see the "...after that" part of the equation getting some attention. There's a lot of talk about "x metres/y degrees by 2100", but these are such arbitrary and transient (to future generations) landmarks that I emphatically believe that we should be reporting the plateaux in temperature and sea level to which the planet is committed, and to which it continually and increasingly becomes committed over time. Don't worry about just our grandchildren - consider the lives of our great-great...great grandchildren, to n generations. They, and the biosphere in which they will live, have a right for us to not FUBAR their existence.
  6. Global Warming - A Health Warning
    Sphaerica @19 I ask because I'm curious (I'm in Australia, so UV and ozone are of concern for me), not to say "ah ha". I had a look at CA readings via the EPA site (http://www.epa.gov/airtrends/weather.html). At the bottom it has 2001-2010 readings per state. This is why I'm curious because observation (so far) does not support the claim. I assume this is another "it's coming, and it's bad" thing?
  7. Climate skeptic claims prebunked by Keeling
    Steve Ryan published a paper on the effect of the volcano on the MLO record. Suffice it to say, slim to none Most impressive are how aircraft measurements match the MLO record over a period of more than a year, showing that MLO does indeed measure CO2 in the free troposphere.
  8. Global Warming - A Health Warning
    18, Dale, I'm just taking a shot at this answer, but... First, we've only seen about 0.6˚C of the 1.4˚C warming to which we have committed, and the likely 2˚C to 4.5˚C for which we are on track. You are unlikely to see an appreciable change in the measurement of ozone (yet) because we haven't yet seen the warming that will help separate the signal from the noise. This is true of a lot of denial reactions. "It hasn't happened yet" is not a valid argument against the proposition that it will happen. Your instinctive search for evidence that it has already happened, followed by an "ah ha" when it hasn't, is a symptom of a case of ostrichitis. Second, and more to the point, the chemistry of ozone creation is fairly clear. It is an endothermic reaction, meaning it requires heat (as well as ultraviolet light). [The reaction is exothermic, however increased temperatures do still increase the rate of reaction.] This means that higher temperatures will increase the rate of reaction, i.e. increase ozone production. California is the perfect testbed. Ozone is already worse in parts of California in the summer months than many places, and California will feel the effects of increased ozone from GW that much more. Ozone is high in California in the summer when skies are clear (letting in the UV) while temperatures are high (speeding the reaction). This is further complicated in California because air inversions are common, which prevent the newly created ozone, as well as pollutants that contribute to its generation, from dispersing. Will everyone everywhere have to worry about ozone? No. Is it an immediate problem, that will affect us right now? No, I don't think so. Is it something that can be ignored? Absolutely not.
  9. Global Warming - A Health Warning
    I've just spent the last hour looking into ozone counts around the world (as I'd heard it was a non-issue in relation to GW). I have to question Agnostic where that information comes from because there are plenty of papers out there showing no trend in ozone in various locations around the world (or a conclusion that no trend is detectable) for decades. Europe especially shows some regions where surface ozone has decreased over the last decade. The only conclusion I can make from looking at numerous papers is that since the mid-70's (when accurate recordings began around the world) it's clear there's no increasing or decreasing trend in surface ozone. Hence why I'm curious how one can conclude that ozone will increase due to GW, when it didn't through the high-climb of the 80's/90's.
  10. New research from last week 33/2012
    Re: "Decrease in biomass burning after year 1500..." I read the abstract and had a thought come to my head, but reading further I found that it was not a new thought. The paper argues against a population collapse driven change in carbon, but I find the coincidence of discovery and disease introduction with the change in carbon flux a bit too much to accept that a steep decline in population had nothing to do with the change in carbon balances. It is a bit too coincidental that the new world is discovered by Europeans, and immediately there is a change in slope on 13C. Can't be sure if I'm looking at a compounding or a confounding.
  11. Global Warming - A Health Warning
    GWS: Yes, you are correct. Anthropogenic precursors for ozone formation are heaviest in areas of dense population resulting in the highest ozone concentration occurring regionally.
  12. IPCC ‘disappeared’ the Medieval Warm Period
    Following guystone's logic to its final conclusion, the IPCC, in order to avoid publishing "mistakes" (meaning incomplete and uncertain science), should probably not publish another assessment report for at least 50 years or so.
  13. It hasn't warmed since 1998
    203, michaelcomaha, As others have pointed out, this needs to be discussed elsewhere, but before you go there to pursue the topic further (as I hope you will), one key point... Interglacials can last a long time, but their duration is not random. We well today understand the orbital forcings behind the glacial transitions (not completely, no, there are lots of gaps, but well enough). The fact is that temperatures for the current interglacial peaked about 8,000 years ago, then started to decline, and should still be declining on the way into the next glacial period. So while a cursory glance at glacial periods suggests that you can ignore current warming, a closer and more educated view of the subject suggests that your own argument shows that you should be even more alarmed than you might have been before. Beyond this, it is also virtually certain that we have guaranteed that the Earth will skip the next glacial period, in spite of the orbital forcings. CO2 levels will not fall enough to permit another glacial period to completely occur (I'm not saying that's a bad thing, just that it's true).
  14. It hasn't warmed since 1998
    According to my research...
    Although it's a response to an off-topic comment, it has general applicability so I will note that it seems to be a characteristic of many non-scientists that they think that reading a few unreferenced, out-of-context sources constitutes "research". It doesn't. 'Real' research is a systematic and thorough process that involves assessing both a broad and a representative section of the area being studied, and doing so in a manner that minimises any personal bias input. Research also requires some understanding of the basics underpinning the field being investigated,in order that the data acquired is properly analysed. What michaelcomaha did, as so many other non-scientists do who want to pretend at making a scientific point, was to simply cherry-pick one or two factoids with which to construct the illusion of having a clue, and a point. He has neither, because he did no actual, real research. He simply read some stuff.
  15. Carbon - the Huge and Yet Overlooked Fossil Fuel Subsidy
    Hi all. I am one of the people involved in compiling the data on support to fossil fuels in OECD countries (the green ones in the chart). Our numbers pertain cover both production- and consumption-side measures, but pertain only to budgetary expenditures and tax expenditures. The latter account for the bulk of the aggregate values. The IEA numbers pertain only to subsidies provided via policies that artificially lower domestic prices to consumers. So the numbers of the two organizations are not entirely comparable. Also, in respect of the OECD estimates we generally avoid the term "subsidy" (preferring to use the broader term, "support") because tax expenditures feature so dominantly and the reference tax systems differ markedly from one country to another. Hence, if one looks at two countries that exempt farmers from paying fuel tax on diesel, the associated tax expenditure measured in a low-taxing country will be less than that measured in the high-taxing country, even though, overall, consumers pay much higher (after-tax) prices for fuel in the higher-tax country. By the way, the IEA does take into account fuel taxes when deriving its estimates for consumption-related subsidies. Whether to equate externalized costs, including those associated with carbon emissions, with subsidies, is a decades-old debate. Clearly it is valid to speak of the externalized costs of different forms of energy, and to treat those that generate larger externalized costs (externalities) as benefiting from a bigger free ride. However, I disagree with renaming externalities "subsidies". For one, the concept of subsidy is much older than that of externality and it has come to be associated with a transfer of value that is the result of a conscious action of a government. By contrast, externalities exist generally through government INaction. Moreover, most externalities would exist even in a state of anarchy -- indeed. Should a driver of a diesel-fueled truck in Somalia be considered to be "subsidized" because he can emit with impunity? In response to Tom Curtis, I agree that some taxes on transport fuels are, essentially, user charges for roads. So they are not necessarily offsetting externalized costs. Also, as he points out, road accidents (and noise pollution) would exist also for electric vehicles (and those fueled by fuels made from waste materials). But my point on that would be that counting the costs of road accidents and noise pollution (as some other authors have done) as a "subsidy" to petroleum fuels is being selective: they would have to be counted for any vehicles that caused as much injury and property damage or emitted as much noise. One additional problem with rebranding externalities as "subsidies" is that this can confuse the public. In the late 1990s there were several well-publicized studies of environmentally harmful subsidies that included non-internalized externalities in their totals of "subsidies". They then said, "Look at all the environmental damage caused by these $2 trillion a year in subsidies!" Problem was, they were already including the cost of the environmental damage in their subsidy estimates -- i.e., they are double-counting. Finally, I disagree with WheelsOC who claims that Libertarians have no place in their economics for externalities. That is not true of any Libertarians that I know. Libertarians are, however, cautious when it comes to recommending government intervention -- particularly interventions that try to remedy the situation by subsidizing alternatives to polluting activities, and which invariably lead to politicians trying to pick winners (as they did with ethanol). Most Libertarians I know would agree that taxing pollution is, in theory at least, a first-best approach to addressing externalized costs.
  16. It hasn't warmed since 1998
    michaelcomaha, I have responded in a more appropriate place.
  17. Climate's changed before
    michaelcomaha - climate does not change without a cause - conservation of energy etc. The "normal" glacial/interglacial cycle is driven by orbital variations and as such are highly predictable. They vary the distribution and strength of incoming solar energy, something easily measured. On that basis, we should be slightly cooling but instead we are warming. The size of the solar forcing creating the glacial change is also quite predictable and measurable. The man-made GHG forcings though are an order of magnitude higher so little wonder climate is changing so much faster than it does during glaciation.
  18. It hasn't warmed since 1998
    michaelcomaha @203, as Composer @204 notes, your inquiry would be more appropriate in the 'climate's changed before' discussion. However, it's worth briefly noting that the planet had been cooling since about 8,000 years ago until about 150 years ago. While there is warming leading into an interglacial, the interglacial periods themselves are relatively stable and generally slightly cooling.
  19. IPCC ‘disappeared’ the Medieval Warm Period
    guystone @2 - I find your comment a bit confusing. You would prefer an oversimplified statement like "this was a mistake" (which is not correct, as other comments have pointed out) to a detailed explanation of exactly where the original graph came from and why it was subsequently replaced, as we have provided here? If you're not looking for detailed explanations, I don't think this is the right site to be exploring.
  20. It hasn't warmed since 1998
    michaelcomaha: Your inquiry is off-topic on this post. To point you in the correct direction (both in terms of re-posting your inquiry should you desire and as an answer) please click on the #1 most used climate myth.
  21. IPCC ‘disappeared’ the Medieval Warm Period
    guystone asks:
    Why all the denial, manipulation, excuses, defencevness, or text?! Not this article but anytime the IPCC is questioned[?]
    The answer is quite simple, guystone: since the vast majority of pseudoskeptic criticisms of the IPCC are without merit, or even when meritorious are unreasonably exaggerated, it is worth making the effort to defend the IPCC. IMO your framing of the situation is out of line. The defence of IPCC processes and contributors only appears to be as you characterize it if the pseudoskeptics' inaccurate portrayals are accepted.
  22. It hasn't warmed since 1998
    How does the current "man is causing global warming" theory jive with the facts that the earth has normal cooling (glacial) and warming (interglacial) cycles? According to my research, it is a fact that we went into a interglacial period (global warming) over 11,000 years ago. So, yes we are in global warming and its cause had nothing to do with man's activities because there weren't many humans 11,000 years ago and the humans that were around didn't drive vehicle or have power plants. Interglacial periods, from my research, can last 40,000 years. My take, considering the above facts, is that man's involvement with global warming is insignificant, it's going to happen with or without man, just like the next glacial period will.
  23. Dikran Marsupial at 03:32 AM on 21 August 2012
    IPCC ‘disappeared’ the Medieval Warm Period
    @guystone Science is provisional, and always subject to updates. The IPCC were asked to produce a summary of the current mainstream view on climate change, and they did. At the time, the figure was not an unreasonable representation of what was know at that time, AFAICS before peer reviewd proxy reconstructions were even available. The FAR was published in 1990, but the first proxy reconstructions didn't appear until several years later. So your characterisation of the IPCC as not having spent enough time on research, is to say the least rather uncharitable. Lamb's figure, and the IPCCs use of it, isn't a "mistake"; it is simply that less was known then than is known now. Of course "skeptic" try to make a mountain out of such molehills. Does the IPCC really need to formally acknowledge everytime some piece of information from a previous report is superceded? No, it is far better for us to understand the provisional nature of science and just read the reports as snapshots of mainstream scientific opinion, as that is actually excatly what they are. "When my information changes, I alter my conclusions. What do you do, sir?" J. M. Keynes.
  24. IPCC ‘disappeared’ the Medieval Warm Period
    guystone, the IPCC didn't create the schematic. Nor did they 'change' it. A hand drawn schematic of roughly what temperatures in central England had been like over the course of the past thousand years (from a 1982 paper) was included in the IPCC FAR. In later reports actual temperature reconstruction graphs for the entire planet from more recent studies were included. Newer science was included in newer reports. That only becomes "a mistake" or "manipulation" when people start lying about what happened. Don't buy into the nonsense.
  25. IPCC ‘disappeared’ the Medieval Warm Period
    I believe that global warming is caused by the human population (or I give it about a 90% chance and about a 50% chance we can actually reduce it enough to make a difference before we actually run out of "fuel") but... The IPCC created the original graph and they changed it. Plain and simple. Why not just say and only say "this was a mistake and we do make mistakes". We didn't spend enough time and research enough on it back when we created the graph because it wasn't as important as it is now. Why all the denial, manipulation, excuses, defencevness, or text?! Not this article but anytime the IPCC is questioned
  26. Climate skeptic claims prebunked by Keeling
    What I find amusing is that given that the measurements are next to a volcano and allegedly volcanoes chuck out huge amounts of CO2 sporadically. The keeling curve is surprisingly smooth. I guess the volcano is intelligent and lets out just enough CO2, even when it has a bit of a build up. OK lets assume it doesn't belch a load of CO2 sporadically, the graph shows that there would be a constant amount interfering with readings all the time. So deduct whatever that mythical amount is and you still get a graph with a positive slope! Are some skeptics saying that the atmospheric CO2 produces a flat line and CO2 from the volcano has risen uniformly for 50 odd years, producing a curve?? That would be easily proven, so lets see the proof.
  27. Global Warming - A Health Warning
    @Agnostic You wrote that "If global temperatures rise more than 2°C, ozone concentration in the lower atmosphere is likely to rise above 100 ppb,..." That suggests that the tropospheric average ozone would increase to that level, which is most likely not going to happen. Have a reference? You probably meant to say locally not globally. The actual expectation is that, while increases will also happen to "background" ozone globally, local exceedances of ozone will become more frequent due to higher temperatures. That relationship is observed everywhere and is a straightforward result of the reduced atmospheric lifetime of a major NOx reservoir, so-called peroxynitrates, into which NOx is sequestered at lower temperatures.
  28. Pielke Jr and McIntyre Assist Christy's Extreme Weather Obfuscation
    Doug wrote: "Pielke's got a good shelf life, though. Never seems to smell bad to journalists, etc." Keep in mind that the only 'science' he has a degree in is political science. Pielke's approach to actual science has always been from a political angle, and that of course includes knowing how to handle journalists. He's a 'professional science analyst and communicator'... a field which frankly I'd rather didn't exist. Science should speak for itself rather than being 'packaged' and 'messaged' for political purposes.
  29. Students sprout creative communications on climate change Inside the Greenhouse
    Would not receive a good grade from me in Visual Communications
    Moderator Response: [Sph] Please make a comment that adds substance to the discussion. A drive by statement of your personal opinion is of no value.
  30. Climate skeptic claims prebunked by Keeling
    I don't know what to say. It's incredible there is (still) a need to debunk well established stuff like this. Sad.
  31. Graeme Rodaughan at 19:46 PM on 20 August 2012
    Climate skeptic claims prebunked by Keeling
    It strikes me that given that Mauna Loa provides a 50+ year instrumental record of CO2 concentration that it provides pretty much the gold standard for CO2 measurement in the late 20th century/early 21st century scientific record. Personally - I don't see how anyone could retain credibility and also claim that CO2 has not risen within the 20th century - at the very least.
  32. Climate skeptic claims prebunked by Keeling
    Here we go, one of my prouder moments ;) It's amazing where forum discussions can go! http://rabett.blogspot.com.au/2009/10/ian-plimer-is-con-artist-one-of.html http://scienceblogs.com/deltoid/2009/10/25/plimer-the-plagiarist/
  33. Climate skeptic claims prebunked by Keeling
    Brilliant. When I learned about d13C measurements, and TA carbon fluxes and looked at the CO2 pumhandle here I thought people knew about this stuff since ~1980, as pumphandle starts from there. It turns out Charlie knew that since 1960... Big time hats off to him. And big time scorn at denialists who keep agnoring such exceptional piece of science.
  34. Climate skeptic claims prebunked by Keeling
    I have an email from Piers Tan from the Mauna Loa observatory debunking a claim regarding this issue made by Plimer in his book. I'll dig it up after work, Eli Rabett picked up on it and has a post about it on his blog somewhere.
  35. Sea Level Isn't Level: This Elastic Earth
    Keep them coming, Rob. Big subjects deliverred in easily digested, bite sized chunks is just what we laypersons are looking for.
  36. Climate skeptic claims prebunked by Keeling
    I tend to think that the measurments from Cape Grim might go someway to debunk this meme as well!
  37. Global Warming - A Health Warning
    Xterrajack expresses two views doubting that AGW contributed to the Moscow heat wave (2010) and questioning the possibility of a 1-2m sea level rise by 2100. Both points have been responded to by Kevin C (9) and witsend (11) and I thank them for that. I would note that Coumou and Rahmstorf (2011) and Hansen et al (2011) come to the conclusion that AGW contributed to the Russian heatwave of 2010 and as noted above, there is growing evidence that in the absence of AGW it was unlikely to have occurred. See http://www.columbia.edu/~jeh1/mailings/2011/20111110_NewClimateDice.pdf Recent data suggests SLR of 0.75 – 2m. by 2100. Hansen and Sato come to the view that SLR in the order of 5m by 2100 is a possible outcome of CO2 emissions continuing on a business as usual basis, a view which I accept. For the purposes of this blog on health, I have opted for the lower estimate. See http://www.skepticalscience.com/sea-level-rise-predictions.htm
  38. Book review: Language Intelligence by Joe Romm
    I have been using much the same:
    "The world is warming and mankind is the cause of it."
  39. actually thoughtful at 11:59 AM on 20 August 2012
    Book review: Language Intelligence by Joe Romm
    Myers-Briggs identifies this problem (communication between rational/analytic and the rest of humanity). Those who are iNtuitive (as opposed to those who are Sensors) - see the world in concepts. This is 25% of the population. 75% see the world concretely - thus the power of metaphors. I repeat the following clear thought as my signature on any internet site I post on (excepting SkS) - "The world is warming; man is to blame". It sometimes starts a conversation. I encourage anyone who posts in areas with signatures to find a similar simple statement to increase the amount of repetition of message. You are certainly welcome to use the sentence I use.
  40. Global Warming - A Health Warning
    I have often tried to frame AGW in terms of rates of change and the limited ability of populations to cope with current rapid change. I think that the same thing is starting to show up in our infrastructure, which has been premised upon a stable climate. Who would have thought that heat waves could derail trains or effect nuclear plants? It also seems like a lot of the health hazards are rather cynically directed at the already-vulnerable, like children. I read about some decent adaptation/mitigation strategies - in Chicago they had public air conditioned facilities, which probably helped a lot of homeless people. But it seems like the resources invested in adaptation and mitigation could be better invested if we just cut our carbon habit. We didn't have those facilities here in the NC triangle, and it was pretty awful. I wrote about a lot of my thoughts on this here: http://topologicoceans.wordpress.com/2012/07/24/global-warming-killed-my-friends-dog/
  41. Global Warming - A Health Warning
    There is also the this direct effect which should be mentioned..... Global warming: Future temperatures could exceed livable limits ... www.sciencedaily.com/releases/2010/05/100504155413.htm 5 May 2010 – Wet-bulb temperature is equivalent to what is felt when wet skin is exposed to moving air. ... The team used climate models to compare the peak wet-bulb temperatures to the .... Part of the iVillage Your Total Health Network ...
  42. Global Warming - A Health Warning
    There's also mental health. Which is going to impact developed nation more because of the greater relative effect..... http://www.forbes.com/sites/davidferris/2012/03/31/is-climate-change-a-mental-health-emergency/
  43. Global Warming - A Health Warning
    It's my understanding that the IPCC predictions for SLR account for thermal expansion but not melting ice, since there is too much uncertainty in models. Given the speed with which ice is actually melting, it seems more than reasonable to assume that SLR will be much more substantial than IPCC projections. (a good summary of arctic ice is here: http://neven1.typepad.com/blog/2012/08/asi-2012-update-9-stormy-weather.html) The Smog Blog has excellent graphs for US air quality: http://alg.umbc.edu/usaq/
  44. Global Warming - A Health Warning
    There is a terrific current ozone data report at http://airgraphing.pscleanair.org/ It covers the Puget Sound Region around the Seattle area. One can track particulates, NO3 - really you can make your own reports. It really is terrific - and other regions should have similar tracking. For instance, See Aug 17th select ozone in the location Enumclaw - or any area. Select Average or hourly measure. Some bad ozone that day - it was 95 degrees, sunny, low wind and lots of combustion pollution. (cough, cough)
  45. Global Warming - A Health Warning
    Xterrajack: You may want to compare Dole et al with Rahmstorf and Coumou (2011), and then read Otto et al (2012). This post at Real Climate is also relevant. The literature and methods on attribution of extreme events is developing quite rapidly at the moment.
  46. Global Warming - A Health Warning
    While there are certainly issues associated with climate change, there are errors and assumptions in this post. For instance, a paper by Dole, et al, 2011 concluded that the intense 2010 Russian heat wave was mainly due to natural internal atmospheric variability. Dole is employed in the Physical Sciences Division of the Earth System Research Laboratory at NOAA. And, for a 1 to 2 meter sea level rise to occur by 2100, it would require the average annual rate of SLR to increase by a rate of 3.7 to 7.3 times the current rate. Those numbers are well above the current upper bounds projected by the IPCC.
  47. Sea Level Isn't Level: This Elastic Earth
    error: should be fig.2 !:=)
  48. Sea Level Isn't Level: This Elastic Earth
    thank you for the super informative post and the illustrations ... I am especially thankful for the animation in fig.1 ...
  49. Global Warming - A Health Warning
    Thanks RPauli and DaveW. Sphaerica, you can download the book (for free!) as a pdf in dropbox here: http://www.deadtrees-dyingforests.com/pillage-plunder-pollute-llc/ I wrote it precisely so that there would be a compilation of sources - peer-reviewed, published science - with links and illustrations. Scientists have in fact been studying the effects of ozone on plants for many decades and the conclusion is that plants are more sensitive to ozone than people or animals. According to Peter Cox of MIT, 40 ppb is the threshold above which ozone damages plants, which absorb it through stomates in foliage and needles. In many parts of the world, particularly in the Northern Hemisphere, 40 ppb is now the persistent background level of tropospheric ozone, while localized peaks are far above that. Even remote areas are impacted as precursors travel across oceans and continents, which has been tracked by satellite. It's well-established that the first impact is to roots, as plants are forced to allocate more energy to repair injury at the point of entry. Hence plants - including trees, perhaps especially since they are exposed to chronic, cumulative damage - are more vulnerable to drought and wind. By the time injury is visible on foliage (which is common by midsummer) internal damage has already occurred. Another well-established effect, observed in both field work and controlled fumigation experiments in both the US and Europe, is that outbreaks of insects, disease and fungus opportunistically attack plants and trees that are weakened by ozone. Hence many uninformed foresters and others who prefer not to blame industrial civilization for the global trend will blame biotic factors for the decline in forest health.
  50. Sea Level Isn't Level: This Elastic Earth
    BC - that's not something I have looked into. Presumably giant ice sheets have accumulated on North America, Greenland and Scandinavia because of the gulf stream - water evaporated off the warm Atlantic sea surface and then transported north. Siberia is not endowed with such a 'moisture conveyor'.

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