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Comments 122751 to 122800:

  1. gallopingcamel at 14:59 PM on 9 March 2010
    Senator Inhofe's attempt to distract us from the scientific realities of global warming
    doug_bostrom (#131), Maybe I have been hanging around this site too long as I find myself agreeing with you again. The shift in carbon isotope ratios is convincing evidence that the extra CO2 is from fossil fuels. My quibble was related to the residence time for "new CO2" in the atmosphere. The IPCC went with a high figure which may explain why the CO2 concentration is not increasing as fast as the IPCC predicted. As I said earlier, just a quibble as the CO2 curve is still a genuine Hockey Stick although the blade appears to be straighter than IPCC (AR4) predictions. With regard to the Trenberth vs. Lindzen issue, the number of scientists backing either one is irrelevant. However, if counting scientist heads did matter, your cause would be lost beyond redemption. The opposition already has over 30,000 signed up: http://en.wikipedia.org/wiki/Oregon_Petition Trenberth has credibility problems because he admits recent cooling trends in private while denying them in public. See Inhofe's "Minority Report". Please look at pages 20 and 22 which quote Trenberth denying recent warming thrice. In (#129) I made a typo. It should have read: Lindzen and Trenberth are experts in climate science, yet they disagree; neither of US can claim sufficient expertise to know which of them is closest to the truth. The Inhofe report published last month has already garnered support from 700 scientists. While counting heads is unimportant in hard science it does give politicians a warm feeling to know they are not alone. I was hoping you would scold me for the "First do no harm..." statement in (#123).
  2. Humans are too insignificant to affect global climate
    John said: "The amount of human CO2 left in the air, called the "airborne fraction", has hovered around 55% since 1958." Isn't the Airborne Fraction around 43-44%? Appears that you have it reversed - 55% would be the proportion absorbed by the sinks. Or is there a higher AF since 1958 because of the time lag for the sinks to absorb the large, recent emissions? A
  3. Does record snowfall disprove global warming?
    To illustrate the above point, as an example, compare February snow cover extent numbers with the Arctic Oscillation index (this applies to all winter months as well). http://climate.rutgers.edu/snowcover/files/moncov.nhland.txt http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/monthly.ao.index.b50.current.ascii.table There's a strong negative annual correlation between the two sets of numbers throughout the overlapping time series (snow cover extent goes back to 1967). Strong negative AO -> higher snow cover extent and vice versa. This isn't surprising, because a strong negative AO tends to push Arctic air much further south. With winter precipitation, this means higher snow cover extent over the northern hemisphere. Note the strong downward trend in the AO since 1989 - a time period some "skeptics" use as a starting point to "disprove" snow cover models.
  4. New observations find underwater Arctic Shelf is perforated and venting methane
    Cowboy writes: Methane, 20 times more effective as CO2 with respect to 'greenhouse' effect, has been increasing in the atmosphere for 200 years, but we want to blame CO2 for warming? Overall, the forcing from methane is +0.48 watts/m2 while that from CO2 is +1.66 watts/m2 (see John's post from last year, here). So while methane is a substantial player in the current radiative imbalance, it's definitely of less importance than CO2 at least for now. You're right that there are natural methane sources such as wetlands (175 Tg/year), termites (20-30 Tg/year), and biochemical processes in the oceans (10 Tg/year). However, anthropogenic emissions (from fossil fuel production, landfills, rice paddies, livestock, landfills, etc.) have more than doubled the natural, pre-agricultural background methane flux. See here for more details. Before humans began modifying the environment, atmospheric methane stayed within the range of 400-700 ppb through repeated glacial/interglacial cycles, for at least the past 650,000 years (see Wolff and Spahni 2007). It's now over 1700 ppb. That increase is due to our agriculture, industry, and land use impacts.
  5. New observations find underwater Arctic Shelf is perforated and venting methane
    CBD: I do agree that where there are higher methane levels in the bottom water (incorrectly, I think, labelled "deep water" on the figure captions on this site) the surface water amounts tend to be relatively less in the deeper water furthest from the shore. I guess this is due to greater oxidation of the methane as it rises in the deeper water. The relationship I was looking for, and couldn't see, is more methane in the bottom water in the shallower area, which is what I would expect to see if the water was warming from the top down. However, as you suggest, there may well be currents that complicate the story. I don't doubt the overall thrust here, I'm just struggling to understand it better.
    Response: The label "deep water" was intentional. I noticed in the paper, they label it "bottom water" but in the press release, they call it "deep water". I just went with the phrase that would make more sense to the average person. It's a judgement call - do you go with the scientifically more precise term or the term that makes more sense to the public?
  6. Does record snowfall disprove global warming?
    libertarianromanticideal says: "and all nine predicted that North American winter snow cover would decline significantly, starting in about 1990." Your link clarifies a few things. First, it says that all 9 models predict a statistically significant downward trend, but only over the course of the entire 21st century, with no real change over the 20th century. It also refers to the northern hemisphere (not just North America). Over the 1990-2010 period, it doesn't project much change. Clearly variations in the Arctic Oscillation (such as the recent negative extremes) can create a lot of snow cover extent variation at the decadal level. You can see similar variation in models with the green line in your link. It's why longer periods need to be looked at when making evaluations: http://tamino.wordpress.com/2010/02/18/cherry-snow/ In other words, give it more time. Cherry-picking time periods is something politicians do. As far as a 10-year-old article that is popular among contrarian circles these days, snow does seem more rare and exciting. The recent generation isn't really used to it.
  7. New observations find underwater Arctic Shelf is perforated and venting methane
    "Cowboy at 16:52 PM on 8 March, 2010 On a romp, posting years-old information, cowboy. That article you cited is of course from 2003; the rise in methane long since resumed. Your point? " 1. Methane, 20 times more effective as CO2 with respect to 'greenhouse' effect, has been increasing in the atmosphere for 200 years, but we want to blame CO2 for warming? 2. Obviously, methane doesn't need any man-made global warming to be released into the atmosphere.
  8. Does record snowfall disprove global warming?
    Berényi Péter, I’m still trying to understand your (very interesting) point. Would it be fair to describe it thus: That any significant change in surface warming (and hence snow melt) due to increasing CO2 will have an asymmetric melting-effect about the winter solstice (when examined at temporally “symmetrical” points in the insolation calendar) due to the effects of CO2 being at the red-end of the spectrum (and so greater at warmer points of the winter)? And that this is, in fact, the opposite of what is being observed? I’m not familiar with any of the numbers involved, but how much of the snowmelt is due to the proximal-cause of local insolation, as opposed to the advection of heat from warmer locations (it also presumably having a latitude component)? I’m still digesting the points about soot particles. Do their effects (if significant) on snowmelt show a pronounced temperature- or spectral-bias ? (Yes, I know they may look black, but does that mean they can always be treated as black-body absorbers/radiators?)
  9. Peter Hogarth at 12:17 PM on 9 March 2010
    Does record snowfall disprove global warming?
    Sorry, title of article is: "Global and regional climate changes due to black carbon" Ramanathan 2008
  10. Jeff Freymueller at 12:17 PM on 9 March 2010
    Does record snowfall disprove global warming?
    #58 Berényi Péter. Your explanation is not clear. I'm not sure whether you are distinguishing between snow fall and snow cover -- they are not the same thing. In the meantime, maybe you can clearly explain why the last snow melting earlier in the spring is evidence against overall warming. Bringing up insolation is a red herring, because temperature is not directly related to insolation (I mean in terms of variation of both through the year in the same place). If it was, the hottest time of year would be in late June, and the coldest in late December. However, in many places the hottest/coldest days are shifted relative to the longest/shortest days. You appear to be assuming that more cold = more snow. You get snowfall when warm, moist air gets chilled, right? Very cold air can hold only a little water vapor, so cold air by itself is not enough to make snow. In many places it has to warm up to snow (read the mountain skier's post early on if you want another opinion). Even the assumption that more cold = more likelihood of snow may be correct only when the temperature is close to 0C, and a small temperature change means the difference between snow and rain. However, that just isn't true for non-coastal areas north of something like 50 N. In those places it is colder than 0C all or almost all of the winter. A bit of warming there will make little or no difference on snow cover for most of the winter. If you look at a map, there is a lot of NH land that falls into this category. So the bottom line is that I just can't see how even the increasing snow cover trend in some parts of the years is automatically related to temperature changes at all. The snow cover at that time is more dependent on when snow falls and sticks. But the melting phase in the spring/summer has a much simpler relationship to temperature, and that part of the year follows exactly what you expect from warming. And beyond all that, how you make the leap from this to disproving CO2-driven warming is just beyond me.
  11. Peter Hogarth at 12:12 PM on 9 March 2010
    Does record snowfall disprove global warming?
    Berényi Péter at 08:33 AM on 9 March, 2010 I think you may have misinterpreted my point, or I wasn't clear (which is likely in an off the cuff remark) As you're aware, if you have soot, you have CO2. Historically and recently they are linked, both a result of burning Carbon based fuel, early 19th century wood and then transition to coal mid 19th century (at least in US) if I remember rightly. This was my point in "difficult to separate soot production from CO2 production" - I didn't mean difficult to filter... I'm aware that the ratio of CO2/soot has got better (?) in recent years due to higher efficincy burning, fuel change, and filtering, but it is just that we are burning a lot more than previously...much more CO2, more gas burning, relatively less particulates in recent decade? I take it you are using the timing of the snow falling/laying/melting as counter evidence of CO2 warming, and promotion of soot to prime suspect? Does this explain warming of the oceans as well? Check: http://www.nature.com/ngeo/journal/v1/n4/full/ngeo156.html. Which states "It is important to emphasize that BC (Black Carbon) reduction can only help delay and not prevent unprecedented climate changes due to CO2 emissions." There is a free version, but you'll have to wait a while for me to track it (and a few more) down.
  12. Does record snowfall disprove global warming?
    I agree with Doug less sea ice in the arctic provides a better moisture for early season snowpack which is after all arrayed around the Arctic Ocean. Snowcover extent is more sensitive to temperature during the melt season, March-August, this is when the extents are so negative. Moreover given that we have had no decline in snowcover extent in the winter, the only way to have large snow cover declines during the melt season is for greater melting due to higher temperatures.
  13. Does record snowfall disprove global warming?
    pdt, absolutely correct. I should have said "are not filtered out efficiently" Berényi Péter, "A low temperature stage does miracles by coagulation." still waiting for this miracle and the other one you promised several times of disproving AGW.
  14. Doug Bostrom at 10:19 AM on 9 March 2010
    Does record snowfall disprove global warming?
    Berényi Péter at 10:10 AM on 9 March, 2010 How can the CO2 thing explain the fact that we are getting ever more snow in late fall and less in late winter? I am listening. For my part I tried to understand how increasing atmospheric C02 could explain why my daily newspaper is sometimes delivered into a puddle at my doorstep but I eventually concluded there was no relationship. But with a little more serious intent, perhaps this is similar to the so-called "lake effect" snows in the area downwind of the Great Lakes, on a grander scale involving the ocean? Early winter sees high surface temperatures on the lakes, which gush evaporating moisture into passing cold fronts leading to heavy snow downwind of the lakes. I suppose the same thing could happen as oceans warm up, even if slightly?
  15. Berényi Péter at 10:10 AM on 9 March 2010
    Does record snowfall disprove global warming?
    Diesel engine for cars may be obsolete. On the other hand large diesel engines may have some merit. Due to scale more filtering can be installed cost effectively. As for nanoparticles. A low temperature stage does miracles by coagulation.
  16. Does record snowfall disprove global warming?
    #57 Riccardo at 09:33 AM on 9 March, 2010 "50 nm particles are not filtered out from automotive diesel exhaust" This is not strictly true. A smaller percentage of 50nm particles are filtered than larger particles, but some are. In other words, the filtration efficiency is size dependent. This is one reason that future regulations will have a number-based component. Off topic, but personally, I wonder if diesel engines can really be viable in the future with all the emissions regulations they will need meet, including HC, CO, NOx, and particle number. NOx is particularly difficult in lean-burn engines. Proposals exist for systems with three separate components in the exhaust as well as a tank of urea and a urea injector. The exhaust system in a stoichiometric engine (most gasoline engines) is much simpler and the efficiencies can be quite high when hybridized like the Prius.
  17. Berényi Péter at 09:38 AM on 9 March 2010
    Does record snowfall disprove global warming?
    #56 Jeff Freymueller at 08:39 AM on 9 March, 2010 "it is hard to see how an overall negative trend in snow cover is a smoking gun" I talk about neither snow extent nor snow volume, not even temperature. I am talking about trends in different parts of the year. Late October is usually much warmer in Northern Hemisphere than February. Also, there is more snow in February than in November. But as time goes by we are getting more and more snow in November, less and less in February. Why is it so? There is more heat in the environment to be trapped when it is warmer. Still, late October snow is getting more frequent while in early march it's diminishing. Snow extent decline from winter to summer solstice is much more pronounced than in the other half of the year, although this part is colder (due to temperature lag caused by ocean heat storage). From end of January to veneral equinox there are seven weeks, from autumnal equinox to mid October there are only three. Late February is colder than mid October, but has the same insolation. Still, the trends are reversed. The only conceivable difference is the state of snow. Old snow has larger crystals, the same amount of soot (inside them) causes more short wave absorption. How can the CO2 thing explain the fact that we are getting ever more snow in late fall and less in late winter? I am listening.
  18. Does record snowfall disprove global warming?
    Berényi Péter, 50 nm particles are not filtered out from automotive diesel exhaust and i'd not say that it's so easy ("just matter of regulations") even for cars, let alone power plants. You only have chemical abatement of NOx. Indeed, Euro IV engines are still a problem due to nanoparticle (smaller than about 1 micron) emissions which are still high.
  19. Mars is warming
    ReBar writes: Someone must have the answer to why dust from volcanos and pollution cause cooling on earth and warming on Mars. Read the article again. Lots of dust (in 1977) made Mars slightly cooler, and less dust (in 1999) made the planet slightly warmer. On both Earth and Mars, more dust = cooler. I hope this helps.
  20. New observations find underwater Arctic Shelf is perforated and venting methane
    For what it's worth (not necessarily much) I'd agree with Andy S that the odd N-S directionality in the figures looks like an artifact of the interpolation of sparse data (via kriging, IDW, or whatever). Look at Fig 1A in the paper (which shows the distributions of stations sampled). There's a much greater sampling density along the coast, and along certain N-S or other transects. Meanwhile, there are some isolated points (e.g., 170E, 73N) that seem to have a disproportionate influence on the interpolation results.
  21. Jeff Freymueller at 08:39 AM on 9 March 2010
    Does record snowfall disprove global warming?
    #47 Berenyi Peter: "... does disprove carbon dioxide generated warming." It seems like I have heard that claim before, and it was wrong the other times, too. First, the overall area under the curve is negative (more on the negative side), so it is hard to see how an overall negative trend in snow cover is a smoking gun against warming. SNOW COVER is not SNOW VOLUME, it is area covered by snow. It may or may not tell you anything about snow volume. Over the northern part of North America, a quite large fraction of the continental area*, temperatures are below freezing for a lot of or most to all of the winter (depending on where you are, where I live it is for about 6 months), and the loss of snow cover in spring depends on when the last of the snow melts. What you observe is a negative trend in snow cover during the spring and summer -- that is, the last snow is disappearing EARLIER in the season now compared to previous years. That sounds like exactly what you would expect from warming. It may be that more snow cover is present in winter compared to earlier years, but temperature only controls snow cover when the temperature is close to 0C/32F, so I have to say, "so what?" *-Canada plus Alaska is a lot bigger than the lower 48 US states, and snow cover is very minor in the southern part of the US and in Mexico, so a majority of the area that sometimes has snow cover is located in the north. This is going to dominate the variation in snow cover.
  22. New observations find underwater Arctic Shelf is perforated and venting methane
    Andy S, actually if you compare the sea floor and sea surface maps (it is more difficult with the atmospheric, which uses a different color scheme) I think you will see that the difference between the two IS 'at right angles'. For instance, high concentrations of methane are retained at the surface along the shallow coastline, but drop to lower concentrations (compared to the sea floor values) further out to sea. The only significant exception to that trend being the high concentrations maintained in roughly the middle of the map... to the north and south of an island which likely sits on an elevated ridge. As to the north south banding... my first guess would be undertow currents. Relatively warm water comes in to the coast, flows under, causes the methane to melt, and pushes it northwards.
  23. Berényi Péter at 08:33 AM on 9 March 2010
    Does record snowfall disprove global warming?
    #52 doug_bostrom at 05:13 AM on 9 March, 2010 "snow cover is diminishing" NH snow cover is diminishing between week 5 (end of January) and week 40 (mid October), increasing otherwise. In last week of the year (late December) NH snow cover is increasing on a 60,000 km2/year rate during the last four decades. I was not clear enough perhaps. I have calculated trends for each week of the year (with a correction for the calendar effect). On the figure you can see this trend for each week of the year. In fact these "weeks" are a bit (34'24.46") longer, making 52 of them fit into the average Gregorian year. Since winter solstice is roughly week 51, snow cover increase starts some 10 weeks earlier and ends five weeks later. As you can see, there is a negative delay of 2-3 weeks. Also, summer solstice is about week 25, but maximum multidecadal decrease rate occurs on week 23-24. The overall trend is downward, since late fall/early winter upward snow cover trend is only 16 weeks long, 30% of the entire year. It is also the darkest part of it, so short wave surface absorptivity multiplied by insolation and integrated for a full year goes up considerably. #53 Peter Hogarth at 05:47 AM on 9 March, 2010 "all this soot, from burning what exactly?" I have told you. In early part of industrial revolution it was steam engines and coal (or wood) burning stoves. Now it's mainly diesel engine exhaust, tire wear, biomass burning and unfiltered smoke from coal fired power plants. The soot particles in question are rather small, average diameter 50 nm. They stay in air until precipitation brings them down (quite effectively). "Difficult to separate soot production from CO2 production" No, it is not. There is soot filter for both diesel engines and power plants. Just a matter of regulations. As opposed to carbon dioxide sequestration, it is not prohibitively expensive nor unattainable. Biofuels are forgettable, forests should be maintained (dead wood removed), tire materials redesigned. The best part of it is that there is almost nothing in the "pipeline". As soon as soot production starts to decrease, particles get washed down and we are left with clean air and white snow. Also, filtering smoke has immediate local benefits, no large scale joint operation is needed (UNO & IPCC can be left out for good).
  24. Does record snowfall disprove global warming?
    Berenyi, temperature and insolation are not as tightly wedded as you claim. Temperatures can drop low enough for snowfall well before the Winter solstice in many parts of the NH. Further, January temperatures in many areas are actually COLDER than December despite being further from the solstice (ditto July temps being warmer than June). Also, snow coverage does not follow a simple curve of decreasing temperature to increasing snow coverage... past a certain point low temperatures can actually reduce snow accumulation. Thus, you cannot say that a 'delay in winter cooling' MUST cause the peak of increased snow coverage to come after the Winter solstice. The minimum insolation does not equate to the minimum temperature which does not equate to the minimum snowfall. And again, if soot accumulation is the primary cause why does the peak loss anomaly take place prior to the Summer solstice? Wouldn't the soot continue to accumulate? Wouldn't insolation two weeks after the solstice be just as strong as insolation two weeks prior... but striking sootier snow and thus causing MORE loss? Your argument has no foundation.
  25. Mars is warming
    Someone must have the answer to why dust from volcanos and pollution cause cooling on earth and warming on Mars.
  26. Peter Hogarth at 05:47 AM on 9 March 2010
    Does record snowfall disprove global warming?
    Berényi Péter at 05:07 AM on 9 March, 2010 One quick question... all this soot, from burning what exactly? Difficult to separate soot production from CO2 production, maybe?
  27. Peter Hogarth at 05:19 AM on 9 March 2010
    Visual depictions of Sea Level Rise
    Ian Love at 23:14 PM on 8 March, 2010 Kaufmann made a number of minor corrections, latest Feb 2010 but chart doesn't change much:
  28. Doug Bostrom at 05:13 AM on 9 March 2010
    Does record snowfall disprove global warming?
    Berényi Péter at 05:07 AM on 9 March 2010 That graph seems quite hopeless as a demonstration of increasing snow cover based on area covered by anomaly above versus below the norm. Discussion over distribution of energy versus time or whatever, the picture seems an open and shut case that snow cover is diminishing. Am I missing something?
  29. Berényi Péter at 05:07 AM on 9 March 2010
    Does record snowfall disprove global warming?
    #49 CBDunkerson at 04:05 AM on 9 March, 2010 "your graph seems entirely consistent with CO2 driven AGW" No, it is not. You should observe the phase relationship. If outgoing longwave radiation is blocked indeed to some extent as the CO2 AGW story puts it, then radiative cooling to space is delayed relative to solar forcing. However, what we actually observe is not a delay. Just the opposite. Most of NH snow cover shrinkage occurs before summer solstice. Also, NH snow cover growth starts a week or so earlier relative to winter solstice than it would be expected based on insolation alone. "there is NO way that increasing soot could result in HIGHER snow coverage at any point of the year" Overall albedo still decreases due to less snow in sunny seasons, so some warming is expected. If any of it goes to increase SST (Sea Surface Temperature), more moisture is available to produce snow in the winter. Also, very small amount of soot is needed to decrease snow albedo (several ppb). It would explain why warming began much earlier (mid 19th century) than carbon dioxide levels started to rise. Folks actually enjoyed smoke in those days. Or at least tolerated it better than we do. Watch what Union Pacific 3985 can do. It gets really nasty from 0:41.
  30. Doug Bostrom at 04:15 AM on 9 March 2010
    Does record snowfall disprove global warming?
    CBDunkerson at 04:05 AM on 9 March, 2010 Playing devil's advocated in a slightly twisted way, let me point out that soot will help nucleate precipitation. Available moisture for precipitation in the meantime is on the upswing thanks to warming of the oceans. It seems reasonable to hypothesize that the two phenomena in concert could actually lead to greater snowfall.
  31. Does record snowfall disprove global warming?
    Berenyi Peter, your graph seems entirely consistent with CO2 driven AGW. Warmer temperatures are shrinking the amount of land which is snow covered year round and increasing precipitation is causing an increase in short term winter snow coverage. The net impact is a decreased annual average northern hemisphere albedo from snow. I see no basis for your claim that this chart suggests soot to be the primary cause of changes in snow cover. For instance, there is NO way that increasing soot could result in HIGHER snow coverage at any point of the year. Nor does it make any sense that the greatest downward snow cover anomaly would take place just BEFORE the Summer solstice... if anything the ongoing accumulation of soot throughout the year should mean increasing losses until fresh snowfall in Winter. "Carbon dioxide has no effect on snowcover." Without carbon dioxide the entire planet would be covered with snow and ice year round.
  32. Skeptical Science now an iPhone app
    Is there any chance of getting a Series 40 version? This would let another few dozen million people use the application. (A conservative estimate; all Nokia phones, for example, ship with at least Series 40 operating system.) Also, S60 phones are backwards compatible with Series 40 applications, so this would add another few dozen million potential users.
  33. HumanityRules at 02:44 AM on 9 March 2010
    Does record snowfall disprove global warming?
    I realise John has said that any one record can't be put down to global warming but I wonder whether this even represents an extreme in precipitation. I had a look at NOAA's precipitation records for Philadelphia and Washington Taking John's definition of extreme precipitation as "(over 50mm in a day)" neither of those two records show a single day in Feb 2010 over 50mm. Snow depth is no measure of the actual amount of water that has fallen as density is variable. It worth looking at wikipedia for "snow". There is nothing for or against global climate change here, it isn't even consistent with our expectations, it's weather.
  34. Berényi Péter at 02:41 AM on 9 March 2010
    Does record snowfall disprove global warming?
    This year's snow proves nothing. However, snowfall pattern for the last four decades does disprove carbon dioxide generated warming. Anyone can access Rutgers snowfiles and check the claim. Norhern Hemisphere snow cover extent has a strong upward trend for November, December & January, strongest for December and a downward trend for the rest of the year. Here is NH snow cover trend for weeks of year, in km^2/year units (1972-2009). If cooling is hampered (e.g. by carbon dioxide), one would expect snow trend to lag insolation. But it's just the opposite. On the other hand if trend is due to decreasing snow albedo, exactly the pattern observed is to be expected. Snow cover should increase while insolation is at its minimum, decrease otherwise. In fact snow trend even precedes insolation slightly, because dirt on snow has more darkening effect if snow is melting away (spring) than while it gets covered by fresh snow every now and then (fall). Simple. Snow is getting dirty, mainly because of soot. From diesel engine exhaust, tire wear, biomass burning and unfiltered smoke from chinese, russian & US coal fired power plants. Carbon dioxide has no effect on snowcover.
  35. Does record snowfall disprove global warming?
    #18 The key factor in producing more snow via a northeaster type of storm is ocean temperature. It is above normal sst that will drive higher evaporation. It is not the specific air temperature of the event that is the key. Interesting paper by Hirsch (2001) http://ams.allenpress.com/archive/1520-0442/14/5/pdf/i1520-0442-14-5-882.pdf #37 The main range of the Himalaya is unusual in that the wet season is also the melt season. Thus, for Nepal, Bhutan, Sikkim and adjacent areas of India, glacier loss will not be as important. The main accumulation in this area coincides with the main melt season. http://glacierchange.wordpress.com/2010/01/20/gangotri-glacier-retreat-and-hydropower/ and http://www.the-cryosphere.net/4/115/2010/tc-4-115-2010.pdf
  36. Visual depictions of Sea Level Rise
    Charlie A (#39) and others wonder about AGW and the rises seen in The Jenreva chart in comment #14. There is a striking similarity to the temperature rise in the arctic as in the recent report ( Kaufman et al. Science 2009): the temperatures are found to rise from about 1800, as does the sea-level. The temperature rise is, of course, attributed to AGW. (Sorry for the mishandled tags giving faulty posts above...)
  37. HumanityRules at 22:35 PM on 8 March 2010
    Does record snowfall disprove global warming?
    Which raises the question what would increase humidity near surface or surface temperature?
  38. HumanityRules at 22:26 PM on 8 March 2010
    Does record snowfall disprove global warming?
    Scrap that when you click on near surface on the side of the page you actually get surface temp.
  39. HumanityRules at 22:23 PM on 8 March 2010
    Does record snowfall disprove global warming?
    Surely the temperature scale on the side of figure 1 is wrong for surface temp. You can play with the UAH data yourself , here This is the official site for the data set?? Any idea why they only provide near surface data back to 2003 (it goes back to 1998 for higher altitudes).
  40. New observations find underwater Arctic Shelf is perforated and venting methane
    Evidence that the ESAS venting is a recent occurance, From ‘The Independant’, “The preliminary findings of the International Siberian Shelf Study 2008, being prepared for publication by the American Geophysical Union, are being overseen by Igor Semiletov of the Far-Eastern branch of the Russian Academy of Sciences. Since 1994, he has led about 10 expeditions in the Laptev Sea but during the 1990s he did not detect any elevated levels of methane. However, since 2003 he reported a rising number of methane “hotspots”, which have now been confirmed using more sensitive instruments on board the Jacob Smirnitskyi.”
  41. Does record snowfall disprove global warming?
    Sometimes what is subjectively perceived by humans as a hard winter has nothing to do with cold but everything to do with snowfall (because we need to shovel it). Consider the following hypothetical example: 1) in year "A" we have a winter that is 20C degrees below freezing but only snows once a week (where I live in Canada, there is hardly any snowfall when it is really cold) 2) in year "B" we have a winter that is 5C degrees below freezing but it snows three times a week. People would probably talk about the winter of year "B" unless someone was watching how much wood was burned in the fireplace :-) On a related note, I used to design work for a ground-source heat-pump manufacturer. That company had access to government-provided "degree-day charts" for every major location in the US and Canada going back 50 years (older stats were available). So if we want to compare this winter to others, detailed historical records do exist.
  42. Arkadiusz Semczyszak at 22:09 PM on 8 March 2010
    New observations find underwater Arctic Shelf is perforated and venting methane
    I recommend in Environmental Microbiology ... e.g. - J. J. Moran et. al. 2007. "Methyl sulfides as intermediates in the anaerobic oxidation of methane".
  43. Arkadiusz Semczyszak at 21:29 PM on 8 March 2010
    New observations find underwater Arctic Shelf is perforated and venting methane
    Of course, would be: soil of tundra
  44. Does record snowfall disprove global warming?
    How is one to read the curves in Figure 1? I have a little problem with some of the colours. - First, 13 years - 12 curves? - There are 3 yellow curves (incl. 2010) but only 2 yellow years. - There are 3 violet curves and 3 violet years; which is which? - Blue and green curves/years - which is which? - There is a grey year (2002). Where is the curve? - There are 2 red years, but only one red curve. Also, where are these very low temperatures between -14 and -18 to be found, and how relevant are they to ground temperatures?
    Response:

    It is a little difficult to read so small. I suggest generating the image yourself via http://discover.itsc.uah.edu/amsutemps/ so you can experiment with different years and different altitudes yourself. The UAH webpage also explains the brightness temperature (to some extent anyway).

  45. Arkadiusz Semczyszak at 21:01 PM on 8 March 2010
    New observations find underwater Arctic Shelf is perforated and venting methane
    "Clathrates are irrelevant to the climate" - but this claim is more likely than the opposite ...
  46. Arkadiusz Semczyszak at 20:57 PM on 8 March 2010
    New observations find underwater Arctic Shelf is perforated and venting methane
    Tundra - Schlesinger (1991) and Leith and Whittaker (19975) - the accumulation of C = 0.2 g/y C, content - 21.6 kg/m2. Wetlands - 15.3 g/y and 68.6 kg/m2 (!). Melting permafrost is "good news" for the L.-V. model oscillations: CH4 - biocarbon.
  47. New observations find underwater Arctic Shelf is perforated and venting methane
    Arkadiusz Semczyszak, no question that at current temperature level wetlands are the major contributors. The problem is that in a more distant past, when the temperature was at level toward which we are heading, there has likely been significant contribution from clathrates. The facts the methane from clathrates didn't play a major role at the end of the Younger-Dryas does not allow you to claim that "Clathrates are irrelevant to the climate" tout court.
  48. Arkadiusz Semczyszak at 20:35 PM on 8 March 2010
    Does record snowfall disprove global warming?
    In Poland, the winter lasts longer than 3 months. On Saturday, I noted the minimum temperature: minus 15 deg C. As long as the current winter (in my meteorological station) I noted in 1983. And the current weather is part of the climate, especially when extreme events shows, if we accept the R. Pielke Seniors definition of climate.
  49. Arkadiusz Semczyszak at 19:54 PM on 8 March 2010
    New observations find underwater Arctic Shelf is perforated and venting methane
    Clathrates ... "The CSIRO and other scientists around the world examined ice cores in Greenland and found that during the Younger Dryas event between approximately 12,800 to 11,500 years ago the increase in atmospheric methane of that time was not sourced from clathrates under the ocean "but from ecological sources such as wetlands"" "We know that emissions of methane are increasing now and that some sources might emit even more with warming, causing a positive climate feedback, or amplification. But this finding suggests that the clathrate source is less susceptible than recently feared,” Dr Smith says." "Researchers at the University of California, Santa Barbara have discovered that only one percent of this dissolved methane escapes into the air – good news for the Earth's atmosphere." "We found that the ocean has an amazing capacity to take up methane that is released into it – even when it is released into shallow water," said Valentine." "This lead the authors to hypothesize that most of the methane is transported below the ocean's surface – away from the seep area. THEN IT IS OXIDIZED BY MICROBIAL ACTIVITY." I recommend in Environmental Microbiology a lot of paper about: system - archeons - sulphate bacteria ... Clathrates are irrelevant to the climate - says reviewed science ... A level (practically constant for a circa decade) of methane in the atmosphere is here: http://larvatusprodeo.net/wp-content/uploads/2009/05/new-scientist.jpg
  50. Miriam O'Brien (Sou) at 19:39 PM on 8 March 2010
    Does record snowfall disprove global warming?
    I haven't checked the records here for intensity of precipitation, but it does seem as if when it rains it's heavier than years ago. I have looked at the records for annual and monthly precipitation and, even though this year we've had lots of rain, that's only compared to the last few dry years. Going on longer term averages, the rainfall is still below average where I live - in line with predictions. I'm going to have to get bigger gutters and more drainpipes for our roof, because the current ones can no longer cope with the heavy downpours, even after I've cleaned them out.

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