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Comments 120101 to 120150:

120101. johnd at 09:23 AM on 4 May 2010
        What causes Arctic amplification?
        I understand that this topic deals specifically with the Arctic, but to be put into perspective with regards to Global warming, then should it not be compared to what is happening concurrently at the Antarctic, or perhaps more accurately, what is not happening at the Antarctic? The average temperatures and trends of each hemisphere are very different with an obvious warming bias in the northern hemisphere and closer to no change in the southern hemisphere. Warming due to CO2 is supposed to be global but if each hemisphere, and each polar region are examined individually, then obviously there are other factors to be considered, like long term cycles that will reverse over time. Certain factors may be in play in the Arctic to produce amplification, but what is happening at the Antarctic that either enhances or offsets them that will be reflected in the global situation?
120102. Riccardo at 08:21 AM on 4 May 2010
        Where is global warming going?
        suibhne, infrared photovoltaic detectors work like photovoltaic solar panels and could in principle be used to produce electricity. Whatever the type of IR detector used, radiation from the atmosphere can, and indeed is, measured. It's energy, no doubt.
120103. suibhne at 08:10 AM on 4 May 2010
        Where is global warming going?
        KR You made my point for me, the "back radiation" cannot do any work. This means it cannot be described as heat. I see you followed my version of the Alamo at Deltoid. Two reasons for the pause in my contributions; 1. The article by H=>Z has still not been published. 2. While you can have a rational discussion with Sylas, Arthur Smith and Stu there are others on that site who simply want to hurl abuse behind the safety of the internet. Thank goodness for a site like Skeptical. While I have not fundamentally changed my position it is not the same as it was say two months ago. All the best.
120104. KR at 07:49 AM on 4 May 2010
        Where is global warming going?
        To clarify my previous comment: the EPA document, Volume 3, Comment 3-45 and Response 3-45 on page 38 is a direct response to the issues in Gerlich and Tscheuschner (2009).
120105. KR at 06:50 AM on 4 May 2010
        Where is global warming going?
        suibhne, take a look at the EPA response, particularly Volume 3, Comment 3-45 and Response 3-45 on page 38. You're welcome to take it up with the EPA, but the vast scientific consensus is that G&T are full of, um, hot air... As to the 324 back radiation discussion, AGAIN!!! - I would love to put that energy to work, preferably in my car. Unfortunately, that's part of the sea-level radiative balance, and there are no cold sinks to divert it to, no opportunity to extract work from it. See the definition of "work", under "Zero work", for this situation. 'Nuf said, suibhne. We went around and around on this under the "Is CO2 a pollutant" thread, you've had the same argument on other blogs, and in each case you've repeatedly refused any physics not from G&T, changed the subject, or just left the discussion midstream when it became clear that nobody found your arguments persuasive. You seem to have a basic misunderstanding of 'zero work' situations of steady state systems, and repeated raise issues of 'work' when there is zero net energy flow. That's really a freshman physics error, and if you don't/won't get it, there's nothing anyone here can say to you... My apologies for the harshness of my reply; I'm more than willing to have a discussion, but you haven't shown a willingness for that. It's quite frankly not worth my time.
120106. Chris G at 05:31 AM on 4 May 2010
        What causes Arctic amplification?
        Frank's post has been pretty well covered already, but I'll add, or restate, a couple of points in ways that I think are simpler. Others can correct me if I'm too far off. We are talking about an amplification of warming. Frank seems to be proposing some mechanism that moves more heat into the arctic region when the region is warmer, than it did when the region was relatively cooler. That is counter-intuitive for me. The primary factor we are looking at is ice loss and regain. Frank's post is all about temperature, but in a phase change, there are large changes in energy with little or no change in measured temperature. When ice melts in the summer, there can be large changes in energy with very little change in temperature. This energy is released as the water freezes, and we see a positive temperature anomaly, in the fall/winter, compared to historical points when the water was already frozen in that place and time of year.
120107. suibhne at 05:24 AM on 4 May 2010
        Where is global warming going?
        KR Yes Ive read Arthur Smiths paper and still prefer G&Ts version of reality. One thing for me sums up the departure of AGW advocates from reality is the figure of 324W/m2 Back Radiation. Why is this huge magnitude of photons not put to some useful work? If this could be shown I would have to reconsider the whole issue.
120108. Philippe Chantreau at 05:06 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        I've dealt with METARs a lot during my days as a pilot and flight instructor. They are automated reports from stations that rely on sensors. Pilots learn to not rely too extensively on reports from unmanned stations, especially for some indications. The station "looks" at a rather small extent of sky, so sky cover may be different from reality. Visibility is ground visibility (normally measured in a direction parallel to the runway axis from the station location) and may not be the same as the slant range visibility that matters when looking for the runway treshold in an instrument approach. Some stations have a precipitation discriminator (type2 if I recall, it usually figures in the remark section of the aviation METAR), others don't. Even the ones that have it can experience temporary malfunctions of the sensor. Some types of precipitation are more likely to "confuse" the sensors, like heavy fog that falls as very fine drizzle (especially below freezing), or freezing rain. The stations are a great tool, but they're only robots and ill-equipped to give an accurate rendition of what goes on in complex weather situations. You could have a cold layer near the ground just a couple of hundred feet thick, with layers of various and higher temperatures as altitude increases, leading to all sorts of variations in precipitation. What was described by Geo-Guy certainly reflects one of these types of situations evolving over time, seen from the ground. It's all weather. I would not put too much trust in such minute amounts of precip as were reported in the METARs linked by John and other posters.
120109. KR at 04:56 AM on 4 May 2010
        Where is global warming going?
        Take a look at the Arthur Smith paper. I've spent a number of hours on G&T (sigh - time I'll never get back, time that would have been better spent with a decent beer); Smith's paper is only 9 pages and very clear. G&T say that there is no such thing as a radiative greenhouse effect. They are quite simply wrong. The magnitudes and numbers for heating via LW radiation trapping and total radiative imbalances are well established by numerous sources; not much I can add there.
120110. suibhne at 04:38 AM on 4 May 2010
        Where is global warming going?
        KR On G&T ....G&T's major confusion seems to be about "heat radiation", aka thermal radiation, emitted by anything above 0K...... I think G&T have been misunderstood on this point. They say radiation can go from a lower temperature body to a higher temperature body. However they say HEAT cannot go from a lower temperature body to a higher temperature body. This is simply stating the "bleedin" obvious in terms of standard thermodynamics.
120111. suibhne at 04:29 AM on 4 May 2010
        Where is global warming going?
        KR On the thought experiment. Like all these gross simplifications it is fetched pretty far. But then so are calculations about the Earths atmosphere that ignores Oceans and so on. I thought it would be interesting though to get a simple value for the Earths thermal capacity or the amount of energy required to increase its temperature by one degree c. A slightly more realistic one for the Oceans gives 30years for a rise of one degree. Assumptions 10% imbalance in radiative equilibrium and using the value of surface radiation 168 w/m2. Both calculations show a large value of thermal inertia.
120112. Phila at 04:08 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        #4 CoalGeologist "It is a "double edged sword" to use single events as providing proof that AGW is occurring, when certain other rare "events" such as this past cold, snowy winter in the eastern U.S. could potentially be cited as proof that AGW is a "hoax"." Without condoning citing single events as "proof" of AGW, I think the difference is that cold, snowy winters are consistent with AGW. While it may be an error to make too much of, say, a heat wave, it's an error of an entirely different type to claim that if it gets cold in the Northern Hemisphere in winter, then AGW must be a hoax. One results from confusion; the other is an attempt to produce it.
120113. iskepticaluser at 03:48 AM on 4 May 2010
        What causes Arctic amplification?
        A recent technical paper, entitled An Initial Estimate of the Cost of Lost Climate Regulation Services Due to Changes in the Arctic Cryosphere and sponsored by the Pew Charitable Trusts, provides another warning of just how strong the feedback effects of a melting arctic may already be. From the summary: “. . . the combined heating effect from the loss of sea ice and snow and the increased release of methane from permafrost in 2010 is roughly equal to releasing an additional 3 billion metric tons [my emphasis] of carbon dioxide into the atmosphere. For comparison, this equals 42 percent of current annual U.S.emissions of greenhouse gases.”
120114. KR at 03:32 AM on 4 May 2010
        Where is global warming going?
        In regards to G&T's more outrageous points, I find Arthur Smiths rebuttal quite clear. Even a single layer of IR scattering (absorbance/emisison) atmosphere can be very simply shown to produce a greenhouse effect, and a more realistic thick layer with temperature gradients and convection will be even more effective. G&T's major confusion seems to be about "heat radiation", aka thermal radiation, emitted by anything above 0K. In section 3.9.3 their misunderstanding (amazing if it isn't intentional) is quite evident, and leads to their claim that heat radiation and energy flow balancing somehow contradicts the 2nd law of thermodynamics. This is a clear attempt on their part to confuse heat flow (net energy changes) with heat radiation.
120115. Ron Crouch at 03:24 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        I had hoped to do this all in one post but there were some technical difficulties with the Environment Canada website. #10 Berényi Péter Your last point surrounding the Metar report for Alert on Apr 3, 2009. Although the Metar report clearly states rain with no accumulation it is unsupported by either hourly reports from Alert airport which only reports ice crystals, or Alert Autonomous which shows a trace of snow.
120116. Geo Guy at 03:13 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        Interesting post and just goes to show that climate doesn't always fall into neat organized categories. In 1973 I was working in Uranium City in northern Saskatchewan (north shore of Lake Athabasca). At 8:00 pm on New Year's eve (73-74)it was -40 F (we hadn't switched to metric then). When we left the festivities at about 12:45 am New Year's day, the temperature had sored to +40F! By 10:00 am later that morning it had dropped to about - 10F. I am sure there are many other oddities in the weather, especially in areas that are isolated as in Northern Canada, that go unreported. Certainly rain in April is not that far fetched - it may have happened 20 km away from the weather station in the past but simply went unreported. Having worked in isolated areas of Canada in the past I can assure you that things such as thunder showers in winter happen, although not that frequently. Calgary (where I currently live) has had significant snow falls in August and golf weather in January, all which seem to be linked to where the jet stream is located. I guess what this can tell us is climate and climate change is a multi-faceted process contingent not upon one single parameter but rather it is the result of the interaction of many parameters.
120117. Doug Bostrom at 02:45 AM on 4 May 2010
        Skeptical Science talk at University of Qld on May 7
        RSVP points out that certain organisms with large populations and short reproductive cycles can benefit in certain circumstances from a change of climate, usually by chewing through a local ecosystem ill-prepared for fast changes. From this we are to derive comfort. Thank you, RSVP. I will welcome my case of West Nile encephalitis or whatever little critters may adapt their way into my province as Good News.
120118. Ron Crouch at 02:34 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        My apologies the link to the daily data for Isachsen for June 1975 should point here.
120119. Riccardo at 02:15 AM on 4 May 2010
        Why are there fewer weather stations and what's the effect?
        Berényi Péter, I know Spencer blog posts and they are not related to station drop out nor with your analysis. The replications I was talking about are on the effect of the dropping of stations and they have done it properly, contrary to your analysis.
120120. Ron Crouch at 02:15 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        #10 Berényi Péter While the Metar report you supplied for Clyde River Apr 18, 1973 clearly states rain it also shows no accumulation. In contrast the Environment Canada Daily and the Environment Canada Hourly records indicate no precipitation at all. Now the Metar report you supplied for Pond Inlet for Apr 25, 1985 clearly states "fog,rain,snow" with an accumulation of .1 cm. The Environment Canada Daily and the Environment Canada Hourly records clearly indicate snow on that date with total precipitation registering .6 mm. Moving on to Isachsen on June 7, 1975 The Metar report indicates fog with no accumulation of precipitation. On June 4, 1975 the Metar report does indicate "rain,snow" with no accumulation. So let's see what Environment Canada has to say about those dates on a daily basis. Well June 7 shows rain accumulation of .3 mm and June 4 shows the same with a trace of snow. So moving on to the hourly report for June 7 it indicates drizzle and fog throughout the day. Now on June 4 the hourly report indicates rain and snow changing to rain late in the evening. So yes the claim that June 7, 1975 being the first recorded rainfall at Isachsen is incorrect as it clearly took place three days earlier on June 4. So we'll have to give David Phillips at least an "E" for effort on that one. Now for the final item which is May 1988 in Alert. The Metar record supplied shows a total of 4 cm precipitation for the month and shows no precipitation on the 21st and .1 cm on the 22nd. So what do the Environment Canada records say. Well it shows a .2 mm accumulation of rain on May 21 followed by a trace of rain on May 22. So in conclusion, seeing that we are dealing with Canadian Climate Records then it is only appropriate when doing an analysis that we use the official Canadian documents from Environment Canada. Other than the small blurb that David had over June 7, 1975 for Isachsen, I'd say the climate record contentions are fairly spot on.
120121. Tom Dayton at 01:45 AM on 4 May 2010
        Why are there fewer weather stations and what's the effect?
        Berenyi Peter, I'll try to be clearer: In the real data analyses, the missing/dropped/discontinued data do not contribute to the overall average trend, because those data are ... missing. In contrast, in your math experiment, the data you dropped did contribute to the overall average trend.
120122. Berényi Péter at 01:42 AM on 4 May 2010
        Why are there fewer weather stations and what's the effect?
        #37 Tom Dayton at 00:16 AM on 4 May, 2010 Every month, more get added as the data dribble in. They do dribble. Records updated in GHCN (v2.mean) between 2010-03-19 & 2010-05-03 according to year:

          2005:    9
          2006:   11
          2008:   13
          2007:   14
          2009:  213
          2010: 1292

        Data earlier than 2005 are not even dribbling.
120123. Juergen Wanninger at 01:33 AM on 4 May 2010
        Flowers blooming earlier now than any time in last 250 years
        If I'm reading the diagram correctly, the botanical spring has moved two or three days forward within the last 250 years. Aren't you aware, that this will show that earth has NOT warmed since that time in any way? Due to earth's axis precession once in 25800 years, the seasons will move completely through our calender in that time. So spring for example should move forward for about 3.6 days in a 250 years period. So I think the result of this paper is the confirmation of a little COOLING of earth within the last 250 years. Quite a good argument for climate scepticals! Isn't it?
120124. Rob Honeycutt at 01:13 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        I have to agree with CO2 (#14). Hail is formed by rising moisture in thunderheads that can sometimes reach over 50,000 feet high. Such storms only form in the presence of warm moist unstable air (summer). One would expect it to be warm at the surface when getting hail.
120125. Tom Dayton at 00:16 AM on 4 May 2010
        Why are there fewer weather stations and what's the effect?
        Berenyi Peter, you are incorrectly assuming that your purely mathematical experiment is an analog of the actual station dropout data. In your experiment, you split the data at an exact midpoint of time, and deliberately and perfectly split lower-trending from higher-trending data. Those choices of yours are what led to--indeed, forced--the existence of the regression to the mean that you found, purely due to the math. You might just as well have removed all the lower-than-average anomalies and expressed shock that the remaining anomalies are higher-than-average. It's the combination of lower with higher that defines the average! In contrast, the real data analyses' station discontinuation point is not at the time midpoint, but long after. Also, the discontinued data are not selected for discontinuation because they trend lower or higher. Indeed, the majority are discontinued only temporarily. Every month, more get added as the data dribble in.
120126. CO2 at 00:01 AM on 4 May 2010
        Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
        CBDunkerson at 04:32 AM on 13 April, 2010 I've used identical arguments when discussing sea ice extent. We also have to differentiate between the arctic and the antarctic. Antarctica's sea ice is unimpeded, the arctic is not. Once the arctic sea ice reaches its limits east and west, the only growth area's are south and north.
120127. CO2 at 23:47 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        HumanityRules #7 Hail is formed in severe thunderstorms reaching great hight. The surface temperature has no more to do with this than creating the conditions that formed the thunderstorm to begin with, which may be 20,30 or 40 degrees C. Are we talking climate change?
120128. Berényi Péter at 23:22 PM on 3 May 2010
        Why are there fewer weather stations and what's the effect?
        #35 Riccardo at 17:13 PM on 3 May, 2010 I cannot see the rationale of the station selection criterion The rationale, as I have already stated, is the fact that dropped stations have slightly higher warming trend prior to dropout than the rest. the very same results has been replicated several times Yes, but all of them have found the right answer to the wrong question. Except Roy Spencer of course, who did something entirely different. He actually collected some more data, which is the proper thing to do anyway. He uses ISH data from ftp://ftp.ncdc.noaa.gov/pub/data/noaa/ but says they are only accessible for ".gov or .edu domains". He may be right. He checks CRUTem3NH against it and finds no serious difference, provided an increasing urban heat island effect is not taken into account. Satellite data are not used in this analysis. However, there ara also several follow-up articles on his website including Spurious Warming in the Jones U.S. Temperatures Since 1973 and The Global Average Urban Heat Island Effect in 2000 Estimated from Station Temperatures and Population Density Data His population density / station warm bias graph is particularly interesting. This effect alone can be responsible for a good portion of "Arctic Amplification" (because population density is pretty low there).
120129. Dennis at 22:39 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        Re: CoalGeologist #4 wrote "It is a 'double edged sword' to use single events as providing proof that AGW is occurring, when certain other rare "events" such as this past cold, snowy winter in the eastern U.S. could potentially be cited as proof that AGW is a 'hoax'." The Eastern U.S. this past winter may indeed be categorized as "snowy," but -- depending on how you categorize "Eastern U.S.," it is debatable to call it "cold" (or, more accuirately, "colder"). While Washington, D.C., had record snowfall totals from December through February, March recorded the forst time since record keeping began that the temperature did not drop below freezing (even overnight). I leave up to the scientists if increased precipitation is linked to a warming world. However, ceteris paribus, higher temperatures are. So, I agree with coal geologists, and have found that the AGW-is-a-hoax crowd have ignored the temperature record int he evidence.
120130. Mythago at 21:34 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        I won't profess to having had time to go through reams and reams of data but to my mind it is possible for all unique or rare or even bizarre events as being nothing more than pure fluke chances of something having happened. Micro-climates exist all over the place. Here in North Oxfordshire we got a massive winter snowfall compared with the last 15 years that I can recall. Is that bizarre? Is that proof that AGW is not happening or is happening? I firmly believe that we have influenced the natural cycles of climate change, which would normally take millennia to occur, by pumping out massive amounts of all manner of polluting gases (AGW gases) and it is obvious that the climate is warming from very basic evidence but I really despair when one-off events are even hinted at as evidence to prove or disprove what is a very obvious trend which is already being proven and is based on global scale, long term evidence. I reckon someone was fishing by putting out the bait and you were conscientious enough to want to genuinely want to answer in as honest a way as possible. However beware the origin of this item. They may seem all interested and curious on the outside but on the inside they are possibly looking for a fight. I bet they try to use some of your article to suggest something alternative and argumentative later on elsewhere. The sceptics are getting desperate for an argument that they can say disproves AGW and will dig as deep as is possible and use whatever tactic is readily available. As the old saying tells us, 'There are lies, damn lies and statistics'. The lists you quote are incontrovertible evidence but they prove nothing unless you try to say they do with some argument, no-matter how well founded, that shows reasonable proof of a pattern or trend. That's when the sceptics strike with counter evidence. Its all a silly game and as far as I am concerned its a waste of time. Lets just put down the charts and tables and get on with abandoning fossil fuels and start being realistic about the planets ability to sustain us as a species. AGW! Its happening. We need to prepare for the worst case scenario and no amount of tables and charts and nit-picking over micro details will stop it happening. Have a nice day. Kev C.
120131. HumanityRules at 21:17 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        Ron, Just to prove I can do something as boring as you in the name of enlightenment I decided to have a look at some of those high Canadian records. I choose Eureka because from the map it looked like the closest to the site of this rain. The max temp in Apr 2010 was -4.7oC (-5.2oC on the weekend in question). So I checked for some other 'high' temps in Apr at Eureka. Here's a few of the balmiest Apr days (year, day in Apr, temp oC) 2010 23rd -4.7 1948 28th -5.0 1951 30th -6.1 1953 25th -3.3 1961 19th -6.7 1971 26th -2.8 1975 28th -5.0 1979 12th -3.1 (these are not all of them, just the warmest in a particular year and I reached my boredom threshold in the mid 80's) While unusual it looks like the temps in 2010 aren't unique. It's a shame the records don't go back further because my understanding is that the 1930's and 1940's were a period of warmer arctic temperatures. Going through the record I noticed all forms of precipitation are rare in Eureka in Apr (average for whole of Apr is 3.5mm). Apr 2010 had 15mm of precipitation. Hope this helps to stop people going off the deep end :)
120132. Berényi Péter at 20:36 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        There is a METAR record for Clyde, Nunavut, 1973 April 18, 20:00 AST (70.48 N, 68.52 W) indicating some rain. Same for Pond Inlet, Nunavut (72.70 N, 77.97 W) on 1985 April 25 01:00 EST and several more on 1995 April 27 Unfortunately Isachsen, Nunavut (78.78 N, 103.53 W) has only reported on 15 & 16 April 2010, so the anecdotic claim about April's rain on 24/25 is not supported by hard evidence. There was some rain there indeed on 1975 June 7 as claimed by the article. However, it could not be the earliest recorded rainfall on that spot, for there was also some rain there three days erlier. And of course there was no rain at all in May, 1988 at Alert, Nunavut (82.50 N, 62.33 W). On the other hand, there was some rain there last year on April 3 (maximum temperature for the day is -32 °C!). That much about reliability of press releases.
120133. JMurphy at 20:13 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        RSVP, your Spanish examples are no doubt uncommon but hardly bizarre, I believe. Barcelona's 'maximum number of snow days in a month' (4) occurred in Feb 1938. Mallorca's maximum, (3) occurred in Jan 1985. The overall picture for the last Spanish Winter doesn't suggest any particularly bizarre events. In fact, the only unusual snow events occurred in A Coruña (Airport), Santander, Madrid (aerodrome of Cuatro Vientos), Toledo, Valencia (Manises airport) and Seville (Airport), where the number of days of precipitation in the form of snow surpassed the previous maximum values for January. On checking those stations, though, you will notice that accurate readings only began in, respectively, 1971, 1945, 1982, 1966 and 1951. (I haven't included Santander because although readings began back in the 20s, it is still showing 1956 as the heaviest year). Since most other places I have checked show a maximum snowfall around the 1930s or 50s, it can be perhaps claimed that the above stations may well have been higher then also, if only accurate readings had been taken at the time. You can check them all here. Uncommon weather indeed but not bizarre, surely ?
120134. wanderers2 at 19:40 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        I was fortunate, as a 19-year-old, to get a job in the Canadian High Arctic (as an assistant carpenter/plumbers/electrician's helper). Yes that meant I visited places like Eureka, Resolute, Mould Bay, and Alert (Weather Station Isaachsen had already been closed by that time). Sighting narwhals from the air (thank you De Havilland Canada for building the incomparable twin otter) was fun. Encountering a polar bear on the ground (me carrying no gun and hiking alone and therefore illustrating the stupidity of my youth) was not. But seeing thousands of nesting murres, or the occasional snowy owl or snow bunting. That experience drove me towards a lifelong pursuit of ecology. Recently I have returned to the arctic, where I consistently see, and hear, from aboriginal persons, hunters, ornithologists, and others: that trends are all congruent with what is expected or projected by climate models. John, you do a great service with this website, and the best part of it is to provide access to the primary literature that others might have a hard time finding. If I had one request it would be to further synthesize some of the recent phenological papers. Thank you.
120135. HumanityRules at 19:36 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        So normal April temps at Resolute and Eureka are -20oC. Apr 24th and 25th 2010 temperature was around -10oC (as high as -6oc). Seems rain wasn't the only strange weather that weekend.
120136. Argus at 19:12 PM on 3 May 2010
        Skeptical Science talk at University of Qld on May 7
        RSVP is right here, of course. Nature adapts all the time, and it works faster than we may think sometimes. I sense a kind of anxiety with many of the debaters on this site. They are always so worried, verything is so alarming all the time, and status quo seems to be the only desirable future.
120137. HumanityRules at 19:08 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        If you want bizarre weather come to Melbourne. One summer day we had temperatures over 30oC followed by an evening hailstorm! How is the rain recorded? What was the temperature on the day?
120138. Berényi Péter at 17:46 PM on 3 May 2010
        What causes Arctic amplification?
        #12 HumanityRules at 12:32 PM on 3 May, 2010 a little sceptical that there is a linear trend There are issues here indeed. Arctic sea ice extent reconstruction for the first half of 20th century at Cryosphere Today is higly problematic. The following book is a must-read for all serious students of the topic (even if it is mentioned at WUWT). Arctic Ice by Nikolai Nikolaevich Zubov, Moscow, 1943 (English translation 1963).
120139. Riccardo at 17:31 PM on 3 May 2010
        What causes Arctic amplification?
        Frank, there is a very good reason for the warm water effect having a larger effect in winter, it's air temperature. Relative to the winter-summer temperature difference, water temperature is almost constant and not far from air temperature in summer. I'd also like to point out that the authors are smart enough to not confuse correlation with causation. Indeed their conclusions don't rely on the correlation but on the physics of the process. The correlation has been properly used to rule out other effects. It always surprises me when people think that reputable scientists (authors and referees) could make such trivial mistakes. Betting on a trivial mistake in a published paper, good chances are that we're missing something.
120140. Riccardo at 17:13 PM on 3 May 2010
        Why are there fewer weather stations and what's the effect?
        In this blog are used to the strong but not supported claims by Berényi Péter. This is just one more example. Indeed, I cannot see the rationale of the station selection criterion nor how any reasonable judgement can be done on the global average temperature trend without proper gridding and averaging. Taking subsets and subsets of subsets is no easy task and the fact that the very same results has been replicated several times using different methodologies makes me think that the only possible conclusion from Peter's mathematics is that his selection criterion is biased.
120141. SoundOff at 16:24 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        Most parts of Canada had an exceptionally mild winter earlier this year. Witness the winter Oympics near washout in Vancouver. It was 25°C on April 2 in my area (Toronto) – the normal is 8°C for that date. That blew away the previous record of 20.6°C in 1967. Incidentally, I wore my winter coat only two days this past winter, unlike every day the previous winter. This anomalous weather must be credited to the recent El Niño, since global warming stopped a while ago according to skeptics.
120142. CoalGeologist at 16:16 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        Several weeks ago, I was enticed into an email "debate" with a AGW "skeptic" who argued that because February, 2010 was the first February on record when there were no tornadoes in the United States, this demonstrated (somehow?) that AGW wasn’t happening. I can’t say I understood his reasoning (if there was any!), but the question raised the issue of the distinction between "weather" and "climate". In this regard, it's best to conform to standard definitions, as appear below in my (overly-long!) post. As shown in the reply by RSVP @#2, using statistically rare "extreme weather events", or even more protracted "extreme climate events" to draw inferences regarding climate change is fertile ground for "cherry picking", and for this reason is best avoided. It is a "double edged sword" to use single events as providing proof that AGW is occurring, when certain other rare "events" such as this past cold, snowy winter in the eastern U.S. could potentially be cited as proof that AGW is a "hoax". Ultimately, climate is a statistical phenomenon. In this regard, single events can be measured in terms of their statistical likelihood, as has been done here. They do not, however, in and of themselves, describe climate, nor climate change, no matter how "bizarre" they may be. The recent flap over whether there has been statistically significant warming in the U.K. since 1995 demonstrates that even multi-year trends can be used to prop up invalid conclusions, if one approaches the topic of climate change with a biased agenda. For reference, the following definitions are from the Glossary section of the IPCC 2007 AR4 Report: "Climate": Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. In various chapters in this report different averaging periods, such as a period of 20 years, are also used. "Extreme Weather Event" AND "Extreme Climate Event": An extreme weather event is an event that is rare at a particular place and time of year. Definitions of rare vary, but an extreme weather event would normally be as rare as or rarer than the 10th or 90th percentile of the observed probability density function. By definition, the characteristics of what is called extreme weather may vary from place to place in an absolute sense. Single extreme events cannot be simply and directly attributed to anthropogenic climate change, as there is always a finite chance the event in question might have occurred naturally. When a pattern of extreme weather persists for some time, such as a season, it may be classed as an extreme climate event, especially if it yields an average or total that is itself extreme (e.g., drought or heavy rainfall over a season). "Climate change" Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer... [the definition continues, but the latter parts are not relevant here.]
120143. Jeff Freymueller at 16:09 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        Very nice detective work! Your last paragraph is well stated. If rain in April starts to be commonplace in these places, that would be empirical evidence for climate change. A single bizarre event, by itself, can be consistent with what is expected from climate change. But you can never be certain that a single bizarre event is really due to climate change, even if climate change makes it more probable.
120144. RSVP at 16:03 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        ...before the Iceland volcano eruption.
120145. RSVP at 16:01 PM on 3 May 2010
        Rain in the Canadian High Arctic in April?
        It was snowing in Barcelona, Venice and Mallorca a few months ago. How common is this?
120146. Jeff Freymueller at 16:00 PM on 3 May 2010
        What causes Arctic amplification?
        Sea ice extent indeed has not changed much in winter (useful graph!), but sea ice THICKNESS has changed a lot at all seasons. The difference between the green curve for year X and the blue for X+1 has been growing over time, and that gives you the area covered by thin first year ice. And as noted in a recent thread here, overall volume is significantly reduced and thick multi-year ice is restricted to an ever shrinking area. Thickness is important because the insulating effect of the ice depends on the thickness of the ice, just like the thickness of the insulation in your house determines its insulation rating (given as Rn in the US, where n is a number). Heat can be transported through the ice in a couple of ways. One is by transport or percolation of water through the ice, but I don't know a lot about how important that is. Even with no water percolating through the ice, heat will be transported through the ice by conduction. The rate of heat flow for conductive heat transport in a uniform material is q = -k*dT/L, where k is a constant that depends on the material, dT is the temperature difference, and L is the distance between the hot and cold sides, in this case the thickness of the ice. The minus sign just means heat flows from hot to cold. If you cut the ice thickness in half, you double the rate of heat flow given the same temperature difference. As the ice gets thinner, the heat flow will be dominated less by conduction, and will approach the heat flow out of open water (heat flow won't go infinite). The thickness of the ice is likely to be a controlling scale for other modes of heat transport as well, but somebody else needs to pick up beyond this because this exhausts my knowledge of heat transport through sea ice. But the bottom line is that in autumn/early winter, there is a lot more open water than before, which then gets covered by thin ice, and the heat transport from ocean to the atmosphere is going to be a lot faster than it used to be throughout the entire winter. Compared to the Arctic atmosphere, the Arctic Ocean is a vast reservoir of heat. Yes, its very cold by ocean standards, but the value of T doesn't matter in the heat flow problem (except for radiation), only the temperature difference (dT). And in the winter dT is large and negative (atmo minus ocean).
120147. RSVP at 15:56 PM on 3 May 2010
        Skeptical Science talk at University of Qld on May 7
        To Philippe Chantreau... Thriving of the Pine Beetle is simple proof that Nature is adapting quickly to the changes.
120148. KR at 12:54 PM on 3 May 2010
        Where is global warming going?
        suibhne - first of all, my apologies, I was thinking of the wrong Trenberth reference. I believe that the "missing heat" thread is discussing that issue. As to your thought experiment of heating the entire earth and the large time constants - crust temperature rises ~20C per kilometer for the first ten kilometers, figure ~200C hotter than the surface 10 kilometers down, when you get to the mantle, where convection currents drop the gradient to 0.3C/kilometer. That means you would only see heating in the top kilometer or so; the rest of the planet is already much hotter, with the upper crust cooling through radiation to space. You won't be heating the mantle, let alone the core (5000-6000C). Warming the crust just slows the cooling of the core, it doesn't heat it. So if you run your calculations with the top 10km (a generous depth) of crust rather than the entire planetary mass, I suspect you will find the time constant for full solar irradiation heating much much smaller. I get a time constant of ~5 years for a 1C temperature rise, not 1080. If you just consider the top 1km, as the crust is 20C hotter below that, your time constant would be six months/degree C; actual thermal conduction speeds in the crust mean that the surface would be much hotter. That makes the 0.7C rise over the last 70-80 years attributable to a very small portion of total irradiance. Incorporating the entire planet in thermal inertia calculations makes no sense when 99.5% of the planet is 200-5500C hotter already. Radiative equilibrium simply describes a steady state situation where incoming radiation matches outgoing radiation - a simple balance of energy. I believe that's what you've described in your last post - an Earth system that cools or warms until it reaches equilibrium. I just have to disagree with your time constants.
120149. HumanityRules at 12:32 PM on 3 May 2010
        What causes Arctic amplification?
        10.Frank I guess the theory goes less sea ice means greater transfer of heat between the ocean and atmosphere. I don't understand how this is greatest in winter and at the highest latitudes. This is both the time and region where sea ice has seen least change. An insulating cover of ice must be present at this time. How does the energy get through the ice? As Frank also mentioned there are questions about the temperature records. No buoy or ship data in winter at the highest latitudes and poor satellite coverage, where are the numbers coming from? (It's a pity the supplementary data isn't working) I'm also a little sceptical that there is a linear trend in winter sea ice over the period (1989-2008). The graph below (from Cryosphere Today) shows that winter sea ice recovered to it's early 20th century norm between 1997-2002. How is the winter sea ice a linear trend?
120150. Ken Lambert at 12:08 PM on 3 May 2010
        Tracking the energy from global warming
        Joe #103 Joe, please convert your kW-hrs to Joules x exponent 10, and we can talk the same language. Interesting proposition with the permafrost, except for the mechanism of channelling all the 'missing heat' there. I don't have a number for the surface area of permafrost on the globe, but is you use roughly 29% land and 71% ocean, and then look at the 29% land and partition the permafrost as say 20% of the land area then you get 6% of the globe surface as permafrost - I think nearly all in the northern hemisphere. Now think about the mechanism gathering Dr Trenberth's global 'Missing' heat residual of 30-100E20 (Av 65E20) Joules into that 6% of the global surface area in a particular part of the northern hemisphere - given the fact that the heat imbalance is global and not directed to any particular spots on the planet.

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