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Comments 106451 to 106500:
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michael sweet at 10:49 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Frank, On Nevins blog we had a discussion earlier this summer about the Polar Hole (the unshaded area at the center of ice pictures) having an unprecedented amount of open water this year. See nevins polar hole image. This area roughly corresponds to your above 80 degree area. Perhaps you can explain why there is so much open water at the pole when the temperature seems to be "cooling". Since the water is about -2C, while the surface of ice floes is closer to 0C, that would acount for the decrease in temperature that you observed. The ice was insulating the atmosphere from the colder water. With the ice now melting, the atmosphere is exposed to the cold water and gets slightly cooler. Do not worry, once the ice is completely gone the water will heat up and the air will go up too. It is interesting to find instances where warming results in transient cooling for odd reasons like the exposure of cold water to the air. Cryosphere Today adjusts their sea ice area for open water at the polar hole. Does anyone know how to get a record of how much they have had to adjust for that and how much this year was over the average? -
FLansner at 10:43 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Wops, heres the grid: http://hidethedecline.eu/media/BLANDET/dmi2010.jpg -
FLansner at 10:38 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Hi Peter Heres grid for 2010. average just under 0,4 C. vertical lines are days, i have estimated each day and summed up. What do you get for 2010? K.R. Frnak -
Albatross at 09:56 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
KR @89, I would if I had the time ;) -
Albatross at 09:51 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Peter @84, If I may make a humble suggestion. I would be interested to see the results of your calculation of the trend in temperatures north of 80 N from 1958-2009 (or 2010) for the period JJA, and/or JAS. I think important to consistently use the same time window (rather than the variable melt season) and to us all the grid points N of 80 N (i.e., "Is it possible that your pixel counting process is introducing bias"). One can then try and fit a OLS model to the data (if appropriate) and test the null hypothesis for zero slope (beta=0). I agree, something does not add up, there are some pretty major differences between your analysis and that of Frank's. Sorry, no ideas as how to deal with the "jumps" in the records when they changed products. kdkd or someone else more familiar with stats might be able to offer to ideas as to how one can homogenize the data. -
DMI and GISS Arctic Temperatures: Hide the Increase?
I attempted to download the DMI data, in order to determine how many days of >= 0C there are on a yearly basis (to look at the length of the summer melt season), but can't seem to get access to it. I would be curious to find out if the length of such a nominal 'melt season' increases over the years since 1958. Is anyone with access to the data willing to take a look? -
Albatross at 09:30 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Frank, Talking of humor, funny that you seem to have completely ignored the data and content of the papers that I presented in my post #72. I say that that because I provided data for all seasons and annual, and all the seasons show warming during the summer going back to 1979, and most of the ice loss has occurred during that time. Anyhow, despite your unsubstantiated allegations, no-one is trying to ignore or "hide" temperature changes over the the summer period as evidenced by the three papers that I cited. You are the one who chose to focus on the short summer period and ignore the rest of the year. In the interests of clarity and honesty, please insist that Anthony Watts change the title of you post at WUWT to: "DMI polarECMWF reanalysis datashows coolersuggests little change inArcticsummer temperatures north of 80 N since 1958" Although to be honest, I would even contest the validity of that statement until seeing the results Peter's latest analysis. Frank "and there fore I think it is relevant to compare todays Arctic conditions with the almosr "human-CO2-free" period 1925-45 with todays conditions." I am not going to let you detract from the misleading title and content of your WUWT post which is under discussion here. Please take your discussion about the 1925-1945 window to a more the appropriate thread. -
archiesteel at 09:11 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
@FLansner: do you have a link to the data you used for your graph? The link you provided pointed to the graph again. "To me this supports the NASA finding that the ice retreat after year 2000 is to some degree result of special wind pattern rather than only warming." I thought that was a Russian research? Do you have a link to the NASA study? -
Waste heat vs greenhouse warming
RSVP - And you completely ignored what I said here, that the sign of the TOA radiation imbalance completely disproves the waste heat theory. As to that 1% accumulating - well, it's been 1% for as long as the 99% greenhouse gas forcing, the CO2 side effects of that energy use, which is actually the major cause for warming. RSVP, you have continued to hold to this theory over >300 postings on multiple threads, despite numerous examples of why you are incorrect. I can only conclude that you have non-rational reasons for clinging to it. Given that, it's simply not worth the time to discuss it any further with you. -
archiesteel at 09:04 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
@FLansner: "Archiesteel: The summer temperatures 80-90N in 1991 was at all time highest since 1958. there after ther summer temperatures trended down to all time minimum 2010." I'm interested in the actual temperature delta. According to figure 2 above this is about 0.5C over 14 years, or 0.36C per decade. "So the trend dive is the largest possible for this data type." How do you know this? Are you arguing the fact that, because this is the largest dive in the instrumental record, then it's the largest *possible*? Think about it. "What more do you want?" A sense of perspective would be nice. Compare the 0.36C/decade cooling with the annual warming of about 2.5C over the same 14 years, or 1.8C/decade. Note that this is an *annual* trend, so it includes the colder melt season temperatures. To claim the Arctic is cooling, as is often done on WUWT and other such sites, is simply wrong, even if there has been a slight cooling melt season trend in the past decade. "Its so funny, all the time we hear you warmies say we have to focus on SUMMER conditions in the Arctic" Two things here: using the term "warmies" doesn't make you very convincing. To the contrary it tends to decrease your credibility. Second: who among us "warmies" said we had to focus on summer temperatures? What we check in summer is not temps (since it's relatively stable above the melting point, as explained above), rather we check sea ice extent and volume. The only ones focusing on summer temperatures are the "skeptics" at WUWT and such. "but then a data set comes by that tells a colder story for the 80N-90N area in summer time. And bingo, you demand FULL YEAR FULL YEAR." It's always been about full year for temperatures. "You may not see the humor, but I do :-)" I guess it's good to be able to laugh at oneself. -
Peter Hogarth at 09:03 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
FLansner at 08:47 AM on 22 October, 2010 At the moment I only have DMI data through beginning of Summer 2010. ERA Interim I can get more easily but this runs a few months behind anyway. -
Waste heat vs greenhouse warming
RSVP >The market is saturated, so the oranges are not shipping Listen carefully: this is physically IMPOSSIBLE in thermodynamics. There is no such thing as "saturation" when we are talking about how much energy a particle emits. The rate of output will always grow to exactly match the rate of input. Not some of the input, ALL of it. Your constantly accumulating surplus cannot and does not exist. -
Peter Hogarth at 08:59 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
FLansner at 07:49 AM on 22 October, 2010 I think you are comparing concern about ice extent minimum or summer ice melt, which requires thermal energy but not necessarily localised temperature rise (the ice is melting, but it stays at zero degrees C) and summer temperatures, which don't vary much for the same reason. The trends indicate that the Arctic sea ice is also reducing in extent for any given month of the year and and the temparature is rising on average throughout the year. I am also just presenting the data, just more of it. -
SRJ at 08:52 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
# 81 FLansner What I meant, is the data online in file format? Eg. as txt, csv, xls or whatever. The numbers. Then I can calculate the trend with errorbars. Or you could do it yourself. -
Bibliovermis at 08:51 AM on 22 October 2010Waste heat vs greenhouse warming
If anthropogenic heat flux radiates, how does it accumulate? -
FLansner at 08:47 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Hi Peter, its hard to say, but I did several checks. What value do you get for 2010? K.R, Frank -
FLansner at 08:42 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
SRJ: Heres the data in question. Due to melting conditions in summer time the temperatures are kept within a more narrow range than the rest of the year. the 1991-2010 dive is a few times bigger than the general noise: http://hidethedecline.eu/media/GlobalIceExtend/fig1.jpg To me this supports the NASA finding that the ice retreat after year 2000 is to some degree result of special wind pattern rather than only warming. K.R. Frank -
Peter Hogarth at 08:39 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
FLansner at 07:58 AM on 22 October, 2010 I have looked again at your “cooling” chart, and I hope you do not mind me reproducing it below. I have double checked and compared with the chart below generated from the official DMI numerical data (the dark line is 5 year average), and though I have not yet updated through 2010, I am concerned that there appear to be significant discrepancies in the period you say shows cooling. Is it possible that your pixel counting process is introducing bias? There is something not quite right here. -
RSVP at 08:34 AM on 22 October 2010Waste heat vs greenhouse warming
#259 Of course anthropogenic heat flux radiates, along with, and indistinguishably from solar heat. However the baseline temperature is referenced from the situation where this heat source is non-existent. The addition of this heat source increases outgoing radiation while at the same time raises the average global temperature. -
skywatcher at 08:28 AM on 22 October 2010Do critics of the hockey stick realise what they're arguing for?
BP - Albatross has provided a better explanation than you could hope for in the explanation of your stomatal paper link. cynicus' last comment is distinctly relevant. You have to be very creful when you base your whole argument on cherry-picked sections of a single dataset, especially if you do not consider the uncertainties or come to the same conclusions as the authors. But what it ultimately comes down to is the fact that every climate change requires a forcing, and to date there is no coherent evidence for large internal variations in climate, let alone large internal variation that just so happen to occur when we are forcing the climate which a factor that even at the low end ought to produce substantial warming. -
Bibliovermis at 08:22 AM on 22 October 2010Waste heat vs greenhouse warming
You have yet to explain why anthropogenic heat flux does not radiate from the planet. Your analogies, the train & the orange grove, are flawed in that they assume a unchanging emission rate. This assumption is not valid when discussing a radiating body, e.g. the planet. Outer space is not saturated with energy. -
RSVP at 08:18 AM on 22 October 2010Waste heat vs greenhouse warming
Bibliovermis #257 As an analogy, situate yourself at an orange grove that takes in oranges for packing and export from other groves in the vicinity. (This represents heat input and output from the Sun.) Every year, 100,000 oranges are brought in from surrounding groves, and 100,000 oranges are shipped to other locales. Not a single orange is left over. BUT! Since the grove began, 100 trees have begun to produce fruit. They are leaving 5000 oranges which either have to ship or rot. The market is saturated, so the oranges are not shipping, however, since the quality of what is coming in from other groves never was really perfect, some of what grows in the local grove does go out. However the 5000 surplus that cant sell remains in the grove. These are not necessarily oranges that grow in the grove, but at any rate 5000 oranges are now added to a rotting pile every year. This represents global warming. -
FLansner at 08:15 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Albatross, you write "Anyhow, here is a paper on polar amplification using the ERA-interim data." Look, There is no doubt that polar amplification happens. But this polar amplification happened around 1925-45 too - before humans CO2 emissions exploded - and there fore I think it is relevant to compare todays Arctic conditions with the almosr "human-CO2-free" period 1925-45 with todays conditions. For instance, the 20 year period 1990-2010 has NOT yet reached an average temperature on Greenland that matches the average temperature on Greenland 1925-45. 1925-45 was warmer than 1990-2010 on greenland. And yet some scientists screeeeeems about the warm Greenland. And the present ice melt as though heat in 1925-45 did not melt ice. But Albatross, perhaps you think that because of the polar amplification, then there physically cannot be an area 80N-90N that is cooling one degree Celsius while far larger areas of the Arctic warms several degrees in the summer. As I wrote: I dont know. But I think its obvious that the areas of Ice retreat that has suddenly open waters releasing heat directly op in the air must have a far warmer trend than the ice coveres areas, for example 80N-90N. And all over the world, there has been more precipitation in later years (perhaps due to Solar minimum + warmer temperatures) and more precipitation in the Arctic ONLY has an albedo/cooling effect in areas with no open waters like 80N-90N. But buttom line: I just presented the data, and then you can considder them or not, its a free world :-) K.R. Frank -
Joe Blog at 08:14 AM on 22 October 2010Do critics of the hockey stick realise what they're arguing for?
e at 05:16 AM on 22 October, 2010 No, energy distribution plays a massive role in climate, that is all the malankovitch cycles do... the younger dryas episode is believed to be the direct result of the slow down of oceanic energy transport. These things matter, and would need to be quantified to calculate sensitivity. I would hate to think what the inferred sensitivity would be using this method on the holocene climate optimum... Or the massive negative feedback inferred from the younger dryas... Ok so we can calculate malancovitch cycles effect through changes in solar distribution, how about the oceans? So currents are going to be driven by variable salinity and energetic state, and atmospheric interaction, driven by variable convection, with pressure systems being affected by stratospheric interactions with variable UV... Its not a case o co2 is this, there fore the average T is thus.. you need to know how the energy is being distributed around the globe, and whether this is affecting the inferred climate of the reconstructions. You need to know all the variables. -
SRJ at 08:12 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
# 76 FLansner "Very significant dive" should be presented as a trend estimate with uncertainty, and maybe also t-value. So what is the trend (and uncertainty) in the DMI summer data since 1991? If the time series is online I could easily do this. And actually, if I understand you correct, the trend was positive until 1991, and negative since 1991. I.e. there is a changepoint. Is that changepoint statistically significant? -
Bibliovermis at 08:01 AM on 22 October 2010Waste heat vs greenhouse warming
RSVP, Please explain how anthropogenic heat flux is different than solar heat flux. Why will AHF build up rather than radiating away from the planet? -
Waste heat vs greenhouse warming
RSVP, We are not "adding energy" by burning fossil fuels, we are temporarily slowing the rate at which energy is released into space, causing a build up of heat. -
FLansner at 07:58 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
KR you write: "Your narrow focus on summer implies some incorrect conclusions - that Arctic temps are declining, that the icecap isn't shrinking." No i certainly dont. The icecap HAS been shrinking, obviosuly, and the shrinking icecap has opened waters that has to be accompanied by heat released to the atmosphere and thus warmer temperatures in large areas. I wrote exactly about the ice covered area 80N-90N in the melt season, no more no less. NO ONE can say that the Arctic ice cap hasnt been shrinking. (honestly, its only some of you alarmist that for some reason reads my words that way, as far as I have seen). K.R. Frank -
Waste heat vs greenhouse warming
RSVP, Please try and understand what is being explained to you. Waste heat is released at a constant rate, it is included as part of the equilibrium input and output. When we are at equilibrium, then that means every unit of energy added by waste heat each year is being output into space. This is the definition of equilibrium, energy in equals energy out. There is no "excess" energy anywhere in the equation. If we increase the annual rate of waste heat release, then in the short term yes energy accumulates. The reason for this is it takes time for equilibrium to be restored. But restore it shall, and once it does energy once again stops accumulating. The reason waste heat doesn't add much to the equation is because the rate isn't growing; it's relatively constant so the earth has had plenty of time to reach equilibrium with respect to waste heat. The analogy to the train is off-base. Imagine instead a train that automatically grows or shrinks itself depending on how many get on or off. This is how thermal equilibrium works. Just keep these two critical concepts in your mind when you think about this: 1. In the long term, energy in MUST equal energy out (waste heat counts as energy in BTW). 2. The rate of thermal radiation is directly proportional to temperature. The faster you heat you add to an object, the faster it radiates that heat. -
RSVP at 07:52 AM on 22 October 2010Waste heat vs greenhouse warming
Energy FROM THE SUN comes in. Energy FROM THE SUN goes out. Add some "CARBONATED" energy from dead dinosaurs for 200 years and you get global warming my friend. -
FLansner at 07:49 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
"archiesteel at 03:56 AM on 22 October, 2010 @FLansner: define "very significant dive," please, then compare that to the annual temperature increase rate." Archiesteel: The summer temperatures 80-90N in 1991 was at all time highest since 1958. there after ther summer temperatures trended down to all time minimum 2010. So the trend dive is the largest possible for this data type. What more do you want? Then some of you guys compare the oscillations in summer melt temperatures with the HUGE oscillations that occur when we have much colder temperatures. Obviously temperatures are kept within a small margin when we have melting consitions in summer time, so to compare just like that with the big oscillations for - 20, 30, 40 Ceisius nonsense. The years back to 1958 shows what oscillations we normally see under melt conditions, and the dive 1991-2010 is as big as anyone could possiblly demand (!!!!!!) Its so funny, all the time we hear you warmies say we have to focus on SUMMER conditions in the Arctic, but then a data set comes by that tells a colder story for the 80N-90N area in summer time. And bingo, you demand FULL YEAR FULL YEAR. You may not see the humor, but I do :-) K.R, Frank -
Bibliovermis at 07:47 AM on 22 October 2010Waste heat vs greenhouse warming
Energy comes in. Energy goes out. When the energy coming in equals the energy going out, equilibrium is reached. Equilibrium does not mean no outgoing radiation. -
RSVP at 07:40 AM on 22 October 2010Waste heat vs greenhouse warming
Bibliovermis "The energy does not remain present in the planetary climate. It radiates out from the planet into space" When the train leaves, and all the seats are taken, you cant get on the train. The hockey stick handle was flat. This implies equilibrium. Any excess energy is excess energy and WILL accumulate. End of story. -
Bibliovermis at 07:37 AM on 22 October 2010Waste heat vs greenhouse warming
RSVP, A value can only be integrated if it remains in the system. Your steadfast refusal to acknowledge that anthropogenic heat flux radiates out from the planet does not change the reality of the situation. -
Doug Bostrom at 07:33 AM on 22 October 2010Waste heat vs greenhouse warming
Hopefully someday, a paper will be passed around with my idea so you can come into the constructive "fold". Usually found on a roll, sometimes folded, sometimes crumpled, never "passed around." -
Peter Hogarth at 07:29 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
FLansner at 20:27 PM on 21 October, 2010 If the moderators will forgive a small diversion on UHI: See chart below on Central England Temperature trend compared with "rural" Armagh temperature trend. Since 1900 the measured 100yr temperature trends are indistinguishable, which casts doubt on claims on some skeptical websites that UHI may have affected the Central England record. These same websites suggest Armagh is unaffected by UHI. -
archiesteel at 07:27 AM on 22 October 2010Waste heat vs greenhouse warming
@RSVP: yes, it *is* consistent. I'm not saying you should stop posting, I'm simply wondering why you said you'd stop posting, and then continued. Since you are so obviously continuing, then I would like a link to that map. @Bibliovermis: yes, he is being obtuse. That's his schtick. -
RSVP at 07:19 AM on 22 October 2010Waste heat vs greenhouse warming
KR #242 "You do understand that the AWH is 1% of the forcings from greenhouse gases" I dare not say, "et tu Brut?" but here we are again. As I asked CBDunkerson. How do you rationale the destruction of this .01 value integrated over 200 years? Multiply 200 by .01, and you get 2. -
Bibliovermis at 07:19 AM on 22 October 2010Waste heat vs greenhouse warming
RSVP, Are you intentionally trying to be obtuse? The energy does not remain present in the planetary climate. It radiates out from the planet into space. -
RSVP at 07:14 AM on 22 October 2010Waste heat vs greenhouse warming
CBDunkerson 241 "If I light a match the energy released by that action does NOT remain present in the climate system for the next 50 years. Indeed, it won't even last the day." I was taught that you cant destroy energy, neither with words or wishful thinking. There are two kinds of people. Those that think and those that point to a committee signing off agreement on papers they never read. Hopefully someday, a paper will be passed around with my idea so you can come into the constructive "fold". -
Peter Hogarth at 07:02 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
FLansner at 03:30 AM on 22 October, 2010 In the DMI data, the ERA-40 data series stops in late 2002. It is replaced by an operational model with slightly higher resolution, T511. There are two more subsequent changes to newer models, the most recent in Jan 2010. These changes are discussed briefly in the advanced article. Here is a zoomed plot of the actual ERA-40 and T511 model data from DMI in the overlap period of Summer 2002. There is a small bias difference. This will cause a small downwards step in the "Summer values above zero degrees C" (zero is dotted line) in 2002. I do not have overlap data for the other transitions. This is one possible cause of small changes in Summer values at around this time. -
cynicus at 06:59 AM on 22 October 2010Do critics of the hockey stick realise what they're arguing for?
In response to BP and Albatross I'm reading a follow up paper from the same authors: Van Hoof et al 2008. I still notice a +/- 10 to 20ppm difference at times between the ice core and stomata data which the paper partly blames on smoothing of the ice core data. The authors also argue for a larger role and acceptance of stomata proxies as a decadal to millenial resolution proxy by the IPCC. They appoint the 13th century increase to massive forest clearing in Europe and the 14th century decrease to reduced human activity after the black death outbreak. Antropogenic changes as such. They then note (which will please BP so he can claim 'bad data'): The presence of high-amplitude CO2 fluctuations as documented by stomatal frequency studies may falsify the IPCC concept that preindustrial temperature variability is constrained by relatively stable atmospheric CO2 levels. But, hold on, don't get exited yet... They also note: A higher degree of CO2 variability during the last millennium must have resulted in a more prominent role for CO2 as a forcing factor of air-temperature changes. So BP's victory over the flatness of the ice core CO2 records is of the Pyrrhic kind which fits perfectly to this threads subject: "Do critics of the of ice core CO2 records realise what they're arguing for?" -
t_p_hamilton at 06:40 AM on 22 October 2010Climate cherry pickers: Falling humidity
JohnD is confusing radiation, radiation forcing and feedback. Solar radiation is not a forcing. Change in solar radiation is a forcing. In other words, if the average solar radiation was the same year after year (it is easy to understand it is location and season dependent) the climate would not change. Forcings by definition are changes not derived from the climate system. Feedbacks by definition are changes derived from the climate system. CO2 increase today is not due to climate, but burning carbon, hence is a forcing. The average increase in water comes about from the changed climate. -
Waste heat vs greenhouse warming
RSVP - Sorry, my link to TOA radiative decreases should be Harries 2001; I had snagged the wrong reference. This is further confirmed as on Is the CO2 effect saturated; namely Griggs 2004 and Chen 2007. It's not waste heat. -
Do critics of the hockey stick realise what they're arguing for?
pm, Personally I don't find hand-waving over "natural internal oscillations" particularly convincing. Whether it technically counts as a "forcing" or not is somewhat beside the point. If the temperature is changing then there must be some underlying physical process responsible for the change. If the MWP was warmer than it is today, then there are two ways this can be squared with current knowledge: a) Sensitivity to known forcings is higher than predicted. b) Some as yet unknown or misunderstood physical process is responsible for the MWP and LIA Most skeptics obsessed with the MWP seem convinced that option b is automatically implied by a warmer than expected MWP. In reality, the only convincing evidence of option b would be a explanation of what this mysterious process is exactly combined with robust empirical evidence that it functions as hypothesized. I have yet to see a single skeptic scientist provide anything close to this. Given the fact that known forcings already recreate the general shape of the temperature trend (the MWP and LIA), option a would fit better with the current evidence. -
Doug Bostrom at 04:44 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Come to think of it, this issue reminds me of the choice of whether to buy a large or small pizza. Purveyors of pizza have good reasons to flog small pies while purchasers should give serious consideration to larger sizes. Use method acting to play both roles while imagining you're also Euclid. In this case, leaving aside the "value proposition" of an 8" versus 16" pie, we're not even sure how much cheese or sauce we're getting. Caveat emptor. -
pmiddents at 04:35 AM on 22 October 2010Do critics of the hockey stick realise what they're arguing for?
Sorry about the broken link. I'll try again. Judith Curry makes an interesting statement in the comments over at her place “This argument about strong MWP and LI implying strong sensitivity drives me nuts. It implies that the MWP and LI are forced. If they are natural internal oscillations, then this would imply lower sensitivity to CO2.” She promises a series on climate sensitivity next year. Paul -
Albatross at 04:34 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Frank @68, Whoosh, look at those goal posts move. You mention the ERA-reanalysis data. Actually the ERA-interim is superior to the ERA-40. Anyhow, here is a paper on polar amplification using the ERA-interim data. Their Fig. 1c shows a warming trend North of the Arctic circle for summers between 1989 and 2008 (trends significant at the 99% confidence level), with a peak warming trend near 80 N. You can also find a discussion here on SS. A previous study by Graversen et al. (2008) looked at ERA-40 data over the Arctic between 1979 and 2001. They too found a warming trend over the high Arctic in the summer months (see their Fig. 1c) over that time. Bekryaev et al. (2010) looked at temperature data poleward of 60 N and calculated trends by season and annually. Here is what they found: Trends from 1959-2008 (C/decade)north of 59 N: Annual: +0.364 Winter: +0.381 Spring: +0.467 Summer: +0.234 N. Hemisphere annual: +0.232 Also look at their Fig. 6 for trends in temperatures in the latitude band 65-75 N since circa 1958. Is the rate of warming during the JJA period over the Arctic slower than observed for the other seasons? Yes, no argument there. But the data from multiple sources agree that there has most definitely not been a cooling trend during the summer as you keeping trying to mislead people into thinking. Why do you choose to ignore the data for the rest of the year Frank, and ignore the rate of change in annual temperatures over the Arctic? I think I know why-- but John or the moderator would probably not let my post through. -
archiesteel at 04:13 AM on 22 October 2010Waste heat vs greenhouse warming
@RSVP: I too am waiting for that map showing how UHI effects "trail away" from cities. Also, I'd like to know why you've come back on your word: "I have tried here to help, but cannot afford to spend time writing things that get deleted. So this is my very last post." Why are you still posting? -
Doug Bostrom at 04:08 AM on 22 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Hmmm. I've not really had a dog in this fight, but on the one hand I see what might be an increase of temperature in some slice of the atmosphere in the upper 10 degrees of latitude of the Arctic, on the other a massive, extended plunge in volume and extent of Arctic sea ice. From a scientific perspective, the DMI data for summer seems quite interesting but from another it seems quite irrelevant. This tension is evident in WUWT's treatment of the summer DMI data, where a failed attempt is made to change everything we know about successive melt seasons so as to be coherent with the DMI data. The struggle to do this leads to depressingly familiar dark mutterings about "adjustments," etc Also, somebody's probably already pointed this out but purely as a matter of geometry it's worth thinking about how the area of the upper 10 degrees of latitude compares with the roughly 24 degrees remaining before hitting the Arctic Circle.
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