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Comments 122701 to 122750:

  1. 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.
  2. 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).
  3. 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.
  4. Mars is warming
    Someone must have the answer to why dust from volcanos and pollution cause cooling on earth and warming on Mars.
  5. 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?
  6. 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:
  7. 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?
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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.
  14. 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
  15. 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...)
  16. 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?
  17. 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.
  18. 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).
  19. 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.”
  20. 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.
  21. 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".
  22. 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
  23. 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).

  24. 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 ...
  25. 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.
  26. 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.
  27. 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.
  28. 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
  29. 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.
  30. Doug Bostrom at 18:02 PM on 8 March 2010
    Does record snowfall disprove global warming?
    Jeff Freymueller at 17:45 PM on 8 March 2010 I find it helpful to think of glaciers as reservoirs and their possible disappearance as a simple, easily understood extension of that analogy. Try telling an engineer responsible for maintaining year round flow through a water utility that you're going to remove several of his impoundments and he should not worry because the total precipitation available to his utility will be unchanged or even increased and he'll call you crazy, with good reason.
  31. Jeff Freymueller at 17:45 PM on 8 March 2010
    Does record snowfall disprove global warming?
    #34, chriscanaris, "I assume Tibet would be very much the kind of territory dependent on glacial melt for irrigation." Yes, very much so. I recently read a profile in Science that suggested the same was true of the mountainous areas of Nepal. As for Ecuador, it may be true at higher elevation, but not in the lowlands. But it is drier farther south in the Andes, and meltwater from glaciers is quite important in parts of Peru and Bolivia.
  32. Doug Bostrom at 16:56 PM on 8 March 2010
    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?
  33. Doug Bostrom at 16:53 PM on 8 March 2010
    It hasn't warmed since 1998
    Cowboy at 16:42 PM on 8 March, 2010 21 years ago that was the latest news. Almost quaint, but for some reason it's finding a lot of currency in the past few weeks. Here's some more of that same article, helping to provide full context: "Dr. Kirby Hanson, the meteorologist who led the study, said in a telephone interview that the findings concerning the United States do not necessarily ''cast doubt'' on previous findings of a worldwide trend toward warmer temperatures, nor do they have a bearing one way or another on the theory that a buildup of pollutants is acting like a greenhouse and causing global warming. He said that the United States occupies only a small percentage of Earth's surface and that the new findings may be the result of regional variations. ... Dr. Hanson of NOAA said today that the new study does not in any way contradict the findings reported by the NASA scientists and others. He said that his study, in which he was joined by George A. Maul and Thomas A. Karl, also of NOAA, looked at only the 48 contiguous states. Dr. Hanson said that global warming caused by the greenhouse effect might have been countered by some cooling phenomenon that has not yet been identified and that the readings in his study recorded the net effect. ''We have to be careful about interpreting things like this,'' he said. One aspect of the study that Dr. Hanson said was interesting was the finding that the urbanization of the United States has apparently not had a statistically significant effect on average temperature readings. A number of scientists have theorized that the replacement of forests and pastures by asphalt streets and concrete buildings, which retain heat, is an important cause of rising temperatures. Dr. Hansen of NASA said today that he had ''no quarrel'' with the findings in the new study. He noted that the United States covered only 1.5 percent of Earth. ''If you have only one degree warming on a global average, how much do you get at random'' when taking measurements in such a relatively small area, he asked rhetorically. ''We are just arguing now about whether the global warming effect is large enough to see,'' he added. ''It is not suprising we are not seeing it in a region that covers only 1.5 percent of the globe.''
  34. New observations find underwater Arctic Shelf is perforated and venting methane
    2003: (emphasis added) "The National Oceanic and Atmospheric Administration (NOAA) reports that atmospheric concentrations of methane, a potent greenhouse gas, have begun to level out AFTER TWO CENTURIES OF INCREASES. In a November 17 press release, NOAA reports that scientists are still trying to determine what this means." http://www.gcrio.org/OnLnDoc/pdf/methane031117.pdf
  35. It hasn't warmed since 1998

    "Did global warming stop in 1998?" Did global warming START in 1998? U.S. Data Since 1895 Fail To Show Warming Trend LINK WASHINGTON, Jan. 25— After examining climate data extending back nearly 100 years, a team of Government scientists has concluded that there has been no significant change in average temperatures or rainfall in the United States over that entire period. While the nation's weather in individual years or even for periods of years has been hotter or cooler and drier or wetter than in other periods, the new study shows that over the last century there has been no trend in one direction or another. The study, made by scientists for the National Oceanic and Atmospheric Administration was published in the current issue of Geophysical Research Letters. It is based on temperature and precipitation readings taken at weather stations around the country from 1895 to 1987. ...

  36. Does record snowfall disprove global warming?
    gallopingcamel at 15:48 PM on 8 March, 2010 There was no record cold in December or January in the U.S. Just take a look at these reports: http://www.ncdc.noaa.gov/sotc/?report=national&year=2010&month=1&submitted=Get+Report Notice there a no record cold states in Dec. or Jan. Record lows and record highs are a different story because that is just variability in the weather fluctuations. The long-term trend is for record highs to outpace lows as demonstrated by Meehl (2009). The cold weather in Eurasia and in the U.S was due to an extreme negative phase of the Arctic Oscillation. When this happens the surface pressure in the Arctic is relatively high and that allows the jet stream to weaken, and cause outbreaks of arctic air to move into middle latitudes. And the Arctic air being replaced by mid latitude air so the arctic is extremely warm. http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html This similar neg. AO pattern also happend last summer in the midwest U.S. which caused it to be a cool summer. The snowstorms on the east coast are consistent with El Nino bringing more precip up the coast clashing with arctic air which I described with the negative AO. These big precipitation events are consistent with global warming, but you can't say any weather extreme was caused by AGW. The southeast U.S., including Florida, was predicted to have a colder than usual winter this year by NOAA back in October: http://www.noaanews.noaa.gov/stories2009/20091015_winteroutlook.html
  37. Doug Bostrom at 16:30 PM on 8 March 2010
    Senator Inhofe's attempt to distract us from the scientific realities of global warming
    gallopingcamel at 02:03 AM on 7 March, 2010 "Next he posits that man made emissions are causing the rise in CO2. Probably OK but I have some quibbles. Let it go." Whoa, pardner! Hold the phone! That's reflective of a misunderstanding on your part which will leave you bereft of complete comprehension of this topic and unable to construct a useful mental model in your head, one delicious taco shy of a combination plate so to speak. Among other techniques isotope ratios especially tell us beyond a reasonable doubt that the rise in C02 we're seeing is anthropogenic. If you have a quibble with this you'll need to take it up with archaeologists and a number of other disciplines depending on radiocarbon dating methods; the calibrations here are an offshoot of radiocarbon dating refinements having nothing directly to do with climate change. As to lag/lead, that's been treated elsewhere in abundance, as Tom has pointed out. I just wanted to jump in and help you over the isotope matter before you wasted more of your time and effort by missing that fact.
  38. Doug Bostrom at 16:07 PM on 8 March 2010
    Senator Inhofe's attempt to distract us from the scientific realities of global warming
    gallopingcamel at 14:00 PM on 8 March 2010 If Lindzen is in disagreement not only with Trenberth but also a majority of other scientists qualified to discriminate between his work and Trenberth's, it's possible and reasonable to conclude Trenberth's analysis is the better of the two, less possible and less reasonable to form the opposite conclusion. That situation indeed being the case, it seems there is after all little controversy to discuss with regard to Lindzen versus Trenberth.
  39. New observations find underwater Arctic Shelf is perforated and venting methane
    In 2007 Shakhova et al wrote, "Until recently, due to slightly negative annual temperatures within the water column and the lid-type coverage of shelf sediments by sub-sea permafrost, old organic carbon buried on the Siberian Arctic shelf was considered completely isolated from the modern carbon cycle." So it seems fair to say the observed venting is a new phenomenon. Shakova et al 2010, wrote, "The release to the atmosphere of only one percent of the methane assumed to be stored in shallow hydrate deposits might alter the current atmospheric burden of methane up to 3 to 4 times" The East Siberian Arctic Shelf covers a similar area to the Siberian traps which has been linked to a large increase in GHG's in the past. As the potential volume of GHG's from the ESAS is so large, perhaps similar to levels released by the Siberian traps, isn't it reasonable to suggest that the effects of ongoing and near complete venting of ESAS Methane will be similar to the effects of the Siberian traps event?
  40. gallopingcamel at 15:48 PM on 8 March 2010
    Does record snowfall disprove global warming?
    It pains me to meekly agree with almost everything in this post. The recent record cold in so many places in the USA and Europe proves absolutely nothing about climate trends. Given the current SSTs (highest since 1998) it would not surprise if this winter's snow records will be followed by a very warm summer in many places.
  41. CO2 lags temperature
    captain_heroic44: The reverse of what is described in this post's paragraph "As the Southern Ocean warms, the solubility of CO2 in water falls (Martin 2005). This causes the oceans to give up more CO2, emitting it into the atmosphere." Cooler oceans can hold more CO2, so the oceans suck it out of the atmosphere.
  42. CO2 effect is saturated
    Hi Riccardo, Thanks for the answer and links. I have trouble enough keeping on top of the literature in my own field, so it is very useful to come to a place like this and have someone with a good knowledge of the particular issue provide/point me to a summary. I saw a good clip on Richard Dawkin's TV today about how to spot baloney, which is perhaps apropos to this matter. One common form of baloney occurs when someone claims that his/her theory shoots down an existing and better understood theory, based on falsifying only one particular aspect of the better understood theory. The new theory, however, can't explain all the other phenomena that are explained by the better understood theory. Thus, the notion that all the multiple lines of evidence for a human forcing on climate can be falsified because all those silly (and agenda-driven!) scientists overlooked CO2 saturation seems to qualify as baloney. Thanks again, M
  43. Does record snowfall disprove global warming?
    neilrieck: Good point about thermohaline circulation. Jeff: An intriguing post about the earth's oblateness. In relation to both your posts, I assume Tibet would be very much the kind of territory dependent on glacial melt for irrigation. Ecuador would be similar I suspect. Your 1997/1998 experience of torrential rain in Tibet during the great ENSO together with your student's experiences in Ecuador that year is anecdotal evidence of potentially complex hydrological responses to warming in these regions.
  44. Does record snowfall disprove global warming?
    I do not know if the snow fall event in England this January was directly linked to climate warming or not, but it is logical. A number of months back I saw a description of the thermohaline circulation (which transports equatorial heat to North-West Europe) and learned that this current is (in part)driven by temperature differences between the equator and poles. As the poles get warmer, the current will deliver less warmth to Europe. Remembering that Moscow and Glasgow are both at the same latitude (55 degrees N), the people in Scotland could end up receiving harder Moscow-like winters.
  45. Jeff Freymueller at 14:28 PM on 8 March 2010
    Does record snowfall disprove global warming?
    This may be off-topic, but it is inspired by Figure 2 in the post. Here's another question that I have been wondering about after seeing Figure 2. There is a big spike in 1998 (maybe 1997-1999) in water vapor over the ocean. 1997-1998 was a whopping El Nino year, and there was some pretty amazing rainfall in some places that year. I experience some of that in Tibet that August, where we were trying to work (but not having much success) because it was the worst flooding in many years due to the heavy rainfall. One of my students was in Ecuador in early 1998, and they were also getting the worst floods in years. The same time period also shows up as an anomalous when you look at the earth's oblateness (deviation from being a sphere). See this paper for example: http://www.sciencemag.org/cgi/content/full/298/5600/1975 What's interesting about this is that the change in oblateness has the look of an event, a short-term change opposite to the usual trend as opposed to a change in trend, which has made the explanation advanced in the paper somewhat controversial. Since that time, as far as I know, oblateness has continued to decrease following the post-glacial rebound trend. I'm posting this question here because I wonder how many other global-averaged quantities had unusual values that year (global temperature was another)? Just fishing for ideas here and looking for replies about climate-related quantities because I can find the solid-earth ones easily enough myself. Here's the abstract of the Dickey et al paper: Earth's dynamic oblateness (J2) has been decreasing due to postglacial rebound (PGR). However, J2 began to increase in 1997, indicating a pronounced global-scale mass redistribution within Earth's system. We have determined that the observed increases in J2 are caused primarily by a recent surge in subpolar glacial melting and by mass shifts in the Southern, Pacific, and Indian oceans. When these effects are removed, the residual trend in J2 (-2.9 x 10-11 year-1) becomes consistent with previous estimates of PGR from satellite and eclipse data. The climatic significance of these rapid shifts in glacial and oceanic mass, however, remains to be investigated.
  46. Jeff Freymueller at 14:09 PM on 8 March 2010
    Does record snowfall disprove global warming?
    #30 chirscanaris, in many parts of high mountain Asia, agriculture is dependent on glacier melt because of the timing of the rain. The snowpack melts too quickly in spring, and they need the extended runoff from spring melting of glaciers. They can't afford to wait until the monsoon rains come to plant because the growing season would be too short. The specifics are no doubt place-dependent, but they might need the timing of rain to change in addition to the amount of precip. For your sea level question, I think the mass of water vapor that can stay in the atmosphere is small enough that it's a fairly small affect. As for the Sahara and Gobi, that's a good question and I would like to know the answer as well. If precipitation patterns change, some places will come out better off and some will end up worse off (either getting drier, or getting too soggy). I don't know if the winners and losers of that can be predicted with any confidence (the WG2 report of the IPCC is probably the place to look).
  47. gallopingcamel at 14:00 PM on 8 March 2010
    Senator Inhofe's attempt to distract us from the scientific realities of global warming
    Tom Dayton, my point is that the AGW predictions of global temperature trends do not fit the facts. The recent cooling trend baffles the Hockey Team. Simply a case of reality trumping theory. Speculations on why the AGW predictions are wrong are indeed distractions, but interesting none the less. Lindzen and Trenberth are experts in climate science, yet they disagree; neither of can claim sufficient expertise to know which of them is closest to the truth.
  48. oracle2world at 13:59 PM on 8 March 2010
    There is no consensus
    Dear Riccardo My point was that science is not "consensus". Science is Occam's Razor. The least long-winded explanation of a dataset is the current model. Folks in the scientific world who are chicken to speak out, is not "consensus". Stomach ulcers were thought to be caused by emotional distress, the consensus belief. Based on a plausible theory, with no one bothering to be skeptical about it. In 1982 a physician Barry Marshall proposed that a previously unidentified bacterium Helicobacter pylori was the cause. It fit the data better, which led to new treatment, that made some drug companies VERY unhappy. Folks back then thought Marshall was completely off his rocker to challenge "the consensus". Exactly like AGW skeptics today are thought to be unhinged. Actually the only question in the whole of AGW, is whether anthropogenic CO2 emissions account for temperature data better than the random variances inherent in climate. Right now, they don't.
  49. oracle2world at 13:37 PM on 8 March 2010
    Human CO2 is a tiny % of CO2 emissions
    That carbon cycle from the IPCC AR4 graphic? Looks a bit different from another one from our friends at the UN: http://unfccc.int/essential_background/feeling_the_heat/items/3158.php In short, how did 6 gigatonnes a few years ago now become 26 gigatonnes of human CO2 releases?
    Response: The UN graphic uses units of carbon. I use units of carbon dioxide. The difference is fairly simple - 1 gigatonne of carbon equals 3.66 gigatonnes of carbon dioxide. I explain the conversion process in more detail at Comparing CO2 emissions to CO2 levels.
  50. oracle2world at 13:27 PM on 8 March 2010
    Was Greenland really green in the past?
    So let me get this straight. A warmer Greenland was a "local phenomenon", but twelve trees in a Siberian forest suffice to represent centuries of global temperature?

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