Arguments
Recent Comments
Prev 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 Next
Comments 96501 to 96550:
-
adelady at 09:41 AM on 8 February 2011Crichton's 'Aliens Cause Global Warming'
I've always held the view - call it a prejudice if you feel unkind - that much of the pseudo-scientific criticism of climate science is driven largely by a 19th century view of science. It's supposed to be about incontrovertible 'hard' facts. The idea that science is really about complexities and uncertainties is very hard to swallow for those of this persuasion. Crichton certainly exhibits this and many comments on blogs also display a plaintive underlying tone of 'why isn't this easy to understand'. People accept 'the science' to a much greater extent in mysterious invisible areas like endocrinology or cosmology. When it's something we feel that can see or touch many people think understanding it should be just as simple. It never is. That's why it's a field of scientific endeavour rather than a description of the colour yellow. -
RickG at 09:39 AM on 8 February 2011Global Warming and Cold Winters
Mozart: ...the heat island effect needs to be considered. One thing you may not understand is that when you see temperature representations that they are reported as anomalies to a specific base period. In other words its the change in temperature that matters not the actual temperature. You might also look at the discussion on the heat island effect here and here on this site. -
mozart at 09:35 AM on 8 February 2011Global Warming and Cold Winters
Fair enough Daniel, but I just sense the welcome is a little cold (if you'll forgive the word). Skeptic, as a term for those who need more proof, seems to understate things a little bit on this site. Heretic seems closer to the truth, when I weigh this little string. No matter I'll soldier on, from time to time. You chaps need a little debate and above all a little humour. Regards. -
Marcus at 09:27 AM on 8 February 2011Articgate: perpetuating the myth that Arctic sea ice has recovered
What I notice from figure #2, now that I can see it clearly, is that 1989 had an unusually low *maximum* extent for the 1980's (by about 0.5 to 1 million sq. kilometers), which is probably why they've chosen that over-say-April 1988 vs April 2008. This is, again, no different from choosing 1998 as a baseline for recent climate change-because it was an unusually hot year for the 1990's. As I said above, the dishonesty of the Denialists is just beyond the pale, yet look how quickly they prosecute even very honest mistakes by the other side! -
Rob Honeycutt at 09:10 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
apiratelooksat50 @ 49 said... "I'm on record of saying that I am willing to consider CO2 as a contributor to global warming." So, you're willing to consider basic, well established, 150 year old physics? That's a good start. You'd be surprised how many can't even get that far. -
mozart at 08:54 AM on 8 February 2011Global Warming and Cold Winters
Sorry old chap, but reading that data, they aren't denying that heat island effects exist. They are simply saying it doesn't affect the global record. That record is of modest temperature increases.....I accept that. But the effect on local records can be significant even if hard to quantify. Look at it this way.....nothing is influencing local minimums down....but according to the very article you site the heat island effect can influence local maximums up. Sufficient reason to be careful.Moderator Response: [Daniel Bailey] Let's start over: Welcome to Skeptical Science! Newcomers typically are urged to Start Hereand then read the Big Picture, after which I urge them watch this. Skeptical Science is an immense resource for those coming here to learn about the science of climate, climate change, the human attribution of it and skeptic's arguments against it. In that regard, you are encouraged to use the Search function in the Upper Left corner of every page. Why? To save everyone time. Chances are there's already a post on one's question and a thread discussion of it. After using the search function, if you still have questions, post them on the most relevant thread & someone here will answer it in due time. Thanks! -
Albatross at 08:43 AM on 8 February 2011Global Warming and Cold Winters
Mozart @119, I was addressing your claims, let us deal with those OK? No need to obfuscate or turn this into a "he said, she said". re: "....pinch of salt because of cherry picking of measurement sites. Many, for example are airports, where the heat island effect needs to be considered. In this subject treating data as factual, is a mistake." Absolute nonsense. That myth and fallacy has been addressed by Menne et al. (2010), as well as by the CCC group. Please stop perpetuating myths and insulting us all here with long debunked (and oftentimes unsubstantiated) contrarian speaking points. -
Global Warming and Cold Winters
mozart - I strongly recommend using the "Search" box. For example, a quick run with "heat island" produces this link, while Temp record is unreliable is even listed on every page of this site, on the left border. If you post on the appropriate page a proper discussion can occur - otherwise we get a scattershot on all threads, and it's difficult to actually follow the issues. Incidentally - both skeptic arguments are incorrect. -
mozart at 08:30 AM on 8 February 2011Global Warming and Cold Winters
Albatross I am no more cherry picking than Sweet is by mentioning Greenland. You will note in my posting above I point out it has no significance. Furthermore these record highs have to be taken with a pinch of salt because of cherry picking of measurement sites. Many, for example are airports, where the heat island effect needs to be considered. In this subject treating data as factual, is a mistake. But there I go off subject again.... -
Global Warming and Cold Winters
mozart - Each and every one of your claims about highs and lows is answered here. -
mozart at 08:26 AM on 8 February 2011Global Warming and Cold Winters
Well KR I'm working off today's energy usage and temperature so today's Co2 seemed more relevant. But I gather I'm off topic, so it's moot. Apologies and regards to all. -
Albatross at 08:23 AM on 8 February 2011Global Warming and Cold Winters
Mozart, you are cherry picking by showing data for 2011 to date, it is only early February for goodness' sakes, those data are not even representative of the boreal winter (austral summer), never mind the meteorological year. Look at 2010, and report back what was observed. That said, to do this properly one has to look at the trends over many years. As demonstrated by Meehl et al. (2009) the ratio of record highs to record lows in increasing. note that the ratio is changing, no-one said no new record minimums will be set, just fewer. Michael sweet, 19 all time national record highs were set around the globe in 2010, not 17 (see here). -
muoncounter at 08:06 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
#47: "these questions remain to be answered" I'm not buying it. Those questions are answered numerous times on SkS, often in discussions in which you've participated. Yet you continually return to the unsubstantiated 'natural cycles' hokum. Perhaps you should be the one answering the questions: what natural cycles are you proposing? what are the 'natural forcings'? Have they already been considered in the models that require an anthropogenic forcing to match the temperature record? Do they stand up to scrutiny? Or do you propose 'magic clouds' a la Spencer? "if we've only had 0.8 degree C warming in the past 150 years" It's the 0.8 degree since 1965 you should be concerned about.
#49: "climate has regularly cycled through glacial and interglacial periods."
Not relevant to the current situation. You're a science teacher, stay on task.
-
Global Warming and Cold Winters
mozart - "So I conclude a doubling of the CO2 extant today, is a long, long way off." The proper term for that line is moving the goalposts. The discussion on this is doubling CO2 from pre-industrial levels, not from what they were yesterday. Secondly, folks, temperature record discussion belongs on Record high temperatures versus record lows. Moderator(s) - I believe this CO2 offshoot is well off-topic? Any suggestions for a more appropriate thread?Moderator Response: [muoncounter] Tried that here; Mozart apparently feels he can dance to his own tune. Move CO2 discussion to a CO2 thread, please. -
mozart at 07:57 AM on 8 February 2011Global Warming and Cold Winters
Sweet...show me where I said they were national records. I haven't seen any national records yet for 2011. So we expand it to a much broader data base of global cities. And please don't say "cherry picked" when I produced the entire list. -
mozart at 07:54 AM on 8 February 2011Global Warming and Cold Winters
Well KR I appreciate those comments, but to me it seems reasonable to believe two things: 1) We will become more carbon efficient in our energy needs, motivated primarily by economic forces. 2) The oceans will continue to absorb 50 to 55% of atmospheric CO2. So I conclude a doubling of the CO2 extant today, is a long, long way off. But that's just my guess. I could go on about the trade-offs but then scadden would discipline me again, and who needs that. -
michael sweet at 07:47 AM on 8 February 2011Global Warming and Cold Winters
Mozart, My original post was 17 national all time records. You have not posted any national records. Who has temerity? -
michael sweet at 07:46 AM on 8 February 2011Global Warming and Cold Winters
Mozart, Quickly scanning your site I see that none of the points you cherry picked are national records. Since it is currently winter in the Northern Henisphere and all the records are land based you would expect more cold records than warm records to be set in the past two weeks. There is more land in the Northern Hemisphere. Your hand picked records do not compare to the 17:1 ratio of All time National hot versus cold records set in 2010, and the yearly record is not biased hot versus cold. I ask you again: what does the ratio have to be for you to be convinced it is not natural: 25:1, 100:1 or 1000:1? -
mozart at 07:43 AM on 8 February 2011Global Warming and Cold Winters
Sweet your counter example was an example of one....Greenland. How you have the temerity to criticize a straight data pull that notes places in 5 different countries is astonishing. -
Bob Lacatena at 07:40 AM on 8 February 2011Articgate: perpetuating the myth that Arctic sea ice has recovered
Here's figure 2, with the contrast slightly improved (and a bad case of jaggies to go with it):
-
Global Warming and Cold Winters
mozart - The 4.15 ppm/year rate with 80% industrial expansion discussed in my previous post assumes that the same percentage of CO2 produce (just under 50%) is absorbed by the oceans. If oceans are limited to absorbing 2ppm/year as they currently are doing, then the rates by 2050 (again, using your numbers) will be 5.75ppm/year increase in CO2 for 80% increase in industrialization - still 2.3ppm/year with no change in industry whatsoever. We only need an additional 165 ppm to reach a doubling of pre-industrial CO2... -
SNRatio at 07:35 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
To me, Spencer's "challenge" indicates lack of insight in scientific processes. As long as we don't have complete descriptions, it is rather inappropriate to "rule out" anything. What we are doing, is looking for the models with the greatest explanative power relative to complexity. We also challenge these best explanations by testing the models in new situations, checking consistency in every possible way etc. It is rather futile to spend time "ruling out" possible explanations that are neither made explicit enough to be tested nor seem to be necessary. So, with Spencer's position, the challenge is, really, on him: To produce tests where the consensus models should be able to perform well, but they fail utterly. It is not enough to present special situations they have not been designed to model well, and where they therefore may fail considerably. Null hypotheses are usually picked as the "simplest" or "most natural" models, and hypothesis testing is mostly about rejecting the null hypothesis. Testing that is intended to provide support for the null hypothesis may be problematic, as the power of the test may be too low. Lots of denialist arguments rely on this, like "with this cold winter/high snow cover/seemingly falling temperatures/...., AGW must be minimal or non-existent". In the case of global warming, when the first null hypothesis of no warming has been rejected, the next step is of course to see if the effects established so far may explain the phenomena adequately. In this respect, Spencer's wishes are in a sense granted, in that "natural" factors, like solar irradiation, volcanism, aerosols and gases are taken into account. And so far, models which have included greenhouse gases have very often performed significantly better than models leaving them out. Thus, the initial null hypotheses of "no effect" are rejected, but this doesn't rule out the possibility that an entirely different modeling approach could lead to other results. But in a situation where the models work well, and rather easily include "new" phenomena, believing in entirely different explanations kicking out the well established factors looks like wishful thinking to me. -
mozart at 07:34 AM on 8 February 2011Global Warming and Cold Winters
Well I apologize for not providing a link, I assumed the herrera site was familiar to most serious students of the topic. But here you go: http://www.mherrera.org/temp.htm -
Global Warming and Cold Winters
mozart - We certainly don't need to double industrial energy use to double CO2 levels. They are increasing now at ~2.3ppm/year, an ongoing rate, any additional industrialization will increase that rate. At current rates (with no changes whatsoever in industry levels) we'll hit a doubling of CO2 over pre-industrial levels in ~70 years, and expected additional industrialization will make that time-frame shorter considerably shorter. Given your numbers, by 2050 we'll be increasing CO2 by an 80% higher rate, 4.15ppm/year. -
mozart at 07:25 AM on 8 February 2011Global Warming and Cold Winters
Now scadden you and I differ on the likely course of CO2. You refer me to a site with wildly varying estimates, most of which are hopelessly out of date following the Global near depression. No doubt those prognosticators that find their estimates within one standard deviation of the mean, feel they are being pretty "conservative". But read the US Energy Information Administrations stats on the growth of energy and you come up with the following: Energy usage from all sources will increase 48% by 2035, off a 2007 base. Taking that to 2011 and extrapolating to 2050....you get a linear trend number of 67%. Call it 80% to allow for compounding. So, even assuming we can't drive any efficiencies in carbon per unit of energy....we don't double carbon output from man made sources. And man made sources constitute a fraction of total CO2 production. Given this and the relatively small rise of 23% in CO2 since 1900, I find your confidence in these wildly differing estimates, bemusing to say the least. -
How We Know Recent Global Warming Is Not Natural
apiratelooksat50 - "I am not misrepresenting your argument..." You certainly misrepresented Dana in this post "Are you stating those forcings are not factors now?" and Dikran here "...are you of the position that only CO2 from human combustion of fossil fuels is the driving force?". Neither they nor anyone else I know of with reasonable knowledge of the subject has asserted that CO2 is the only forcing involved involved in climate. Just that it's the dominant one right now raising temperatures, which would otherwise have declined over the last 50 years. I think I'm fully justified in calling those posts strawman arguments. As to attributing current changes to "natural cycles", I suggest looking closely at the graph muoncounter provided. Current climate behavior (change rates) matches nothing seen in the Holocene or any previous interglacials, except perhaps the PETM event. -
Albatross at 07:15 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Pirate @47, That is what people have been trying to tell you for ages now. That said, you forgot to include this part immediately below those questions: "Paleoclimatology offers help in answering each of these questions. Several of the paleoclimate studies reported in this web document have begun efforts to attribute past climate change to both natural and human causes, and to estimate how much of the current warming is due to humans (i.e., greenhouse warming). The best estimate is that about 50% of the observed global warming is due to greenhouse gas increases. The paleo record also tells us how much temperature change occurred in the past when carbon dioxide levels were different. Studies show that the 100 ppm reduction in carbon dioxide during the last glacial was accompanied by a 3°C cooling in the western tropical oceans. This amount of temperature change is consistent with the change predicted by numerical climate model simulations. Changes at higher latitudes were much larger and included the growth of large ice sheets." That was back in early 2009, and the contribution from GHGs is going to increase with time as GHG levels continue to escalate. Pirate are you suggesting that we should only take action if we have "complete" confidence? That would be absurd. The 95% confidence limits for expected climate sensitivity for doubling CO2 have been published (e.g., Annan and Hargreaves 2009) and calculated to lie between +1.5 and +4 K, with a most likely value of +3 K. -
michael sweet at 07:07 AM on 8 February 2011Global Warming and Cold Winters
Mozart, I posted 17 National all time hot records records for 2010. The data you have posted cannot possibly be national records, since I see many that are duplicate. Please weed through the chaff and see if any of your temperatures is a national record. I notice that you have not added any of the record tempertaures in Greenland and Northern Canada, no surprises there. You can continue to post your cherry picked data, but when we get to the final data you will see that January was a pretty average month around the globe. A handful of single data point cold records doesn't amount to anything next to 17 all time hot records for a country. -
Jeff T at 07:03 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Dana, Thank you for this useful summary. However, there is one statement that bothers me: "Another human fingerprint is the higher rate of warming at night than during the day." This statement is presented as if it is obvious. It's not. Can you explain why "greenhouse gases are able to make more of a difference in the surface temperature" at night? Braganza 2004 and Alexander 2006 do show that nighttime warming has been greater than daytime warming. Braganza also shows the change in diurnal temperature range (DTR) as predicted by GCM simulations. The predicted change is negative, but is almost consistent with no change. The observed change in DTR is also negative, but it is approximately 3 times as large as the predicted change. With that sort of discrepancy between the data and the model, one can't credibly claim that the data support the model.Moderator Response: [Daniel Bailey] This prediction goes all the way back to Arrhenius in 1896, was confirmed by (among others) Dai et al 1999, Sherwood et al 2005 and is discussed in detail here. -
apiratelooksat50 at 06:58 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
KR @ 43 I am not misrepresenting your argument. I'm asking a clarification so I do not do just that. The Earth's climate has regularly cycled through glacial and interglacial periods. There has to be a force or forces to cause that. Those changes are observable. Milankovitch cycles have been proposed as one of the possible forces. Through other postings on this site it is evident that CO2 lags temperature, though they do appear linked otherwise. I'm on record of saying that I am willing to consider CO2 as a contributor to global warming. -
mozart at 06:54 AM on 8 February 2011Global Warming and Cold Winters
Well Michael "wild" it may be, but it's not unsupported. In Herrera's definitive site you will find the following: Kaikohe (New Zealand) max. 40.6 Bayanbulak (China) min. -49.6 Woomera (Australia) max. 48.1 Salmon Gums (Australia) max. 46.3 Pecos Ranger (New Mexico,USA) min. -35 Ruidoso (New Mexico,USA) min. -32.8 Safford (Arizona,USA) min. -15 Chihuahua (Mexico) min. -16 Ciudad Delicias (Mexico) min. -18 Durango City (Mexico) min. -11.5 El Carrizo (Mexico) min. -2.5 Los Mochis (Mexico) min. -1.5 Guasave (Mexico) min. 0 Timaru (New Zealand) max. 40.3 I make that 10 new minimums and 4 new maximums. But let me hasten to say, I attach no importance to these empirical observations. There are many more new maximums in the past years, which is consistent with slowly rising temperatures. No need to apologize.Moderator Response: [Daniel Bailey] Actually, you were asked to provide a link to the sources you've used to base your claims on. You still have not done so. -
dana1981 at 06:48 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
apiratelooksat50 #36 - see my comment #35 garythompson #39 - as other comments have noted, climate scientists have examined the coupling of natural forcings with anthropogenic ones. My favorite example is Meehl et al. (2004), which I believe is the source of Daniel Bailey's figure in comment #44. Albatross #46 - thanks! I agree, Spencer's challenge is implying that other climate scientists ignore natural forcings, which is clearly not the case. Good reference to Norris too. -
apiratelooksat50 at 06:43 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Muon @ 45 From the NOAA website from where you pulled that graph. "For example, these questions remain to be answered with complete confidence: •How much warming has occurred due to anthropogenic increases in atmospheric trace-gas levels? •How much warming will occur in the future? •What other changes will occur with future warming?" To have some common ground where we can discuss what is happening to the climate, this gives us a good basis that I think we can both work with. Also, has the data used to generate that graph been used elswhere? It doesn't look to scale, especially if we've only had 0.8 degree C warming in the past 150 years. -
Bob Lacatena at 06:33 AM on 8 February 2011Articgate: perpetuating the myth that Arctic sea ice has recovered
This graph from Peter Gleick's site is also great for highlighting the cherry pick: Misrepresenting Climate Science: Cherry-Picking Data to Hide the Disappearance of Arctic Ice
http://images.huffingtonpost.com/2011-02-07-Arcticgateimages1A.jpg
-
Albatross at 06:14 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Dana, you have exceeded your usual high standards with this post. Regarding Spencer's challenge. It is iMHO very underhanded of him and probably an effort to fabricate "debate". It also just reinforces pre-conceived notions by some that the mainstream climate science ignores natural variability (which is most definitely does not, start reading the IPCC report here) or that the warming can me attributed to some mystical, hitherto undiscovered driver. The scientific literature abounds with example of papers investigating the role of natural variability on regional and global temperatures and precipitation. Spencer's "challenge" really does smack of desperation and wishful thinking. Regarding clouds, that is a tricky one. As Norris (an expert in the field) data issues are a limiting factor in elucidating the role of clouds (see Norris and Slingo (2009). That said he has tried, very hard I might add, to identify trends in low clouds and their possible contribution to the observed temperature changes. His recent paper in Science (Clement et al. 2010) finds evidence for a positive feedback, with warming leading to decreased low-level cloud cover which in turn causes more warming. In a presentation made by Norris in 2009, he made the following statements after considering all the best available data: And from Norris' "summary": • cloud changes since 1952 have had a net cooling effect on the Earth He also of the opinion that: "internal climate variability is unlikely to produce cloud trends occurring over the length of 46 years • anthropogenic or natural external forcing is unlikely to directly produce the observed cloud trends • an internal response of the climate system to external forcing could produce the cloud trends • there is not yet enough information to attribute the cloud trends to anthropogenic global warming" -
Miriam O'Brien (Sou) at 06:11 AM on 8 February 2011Crichton's 'Aliens Cause Global Warming'
This is an 'aha!' moment for me. I'd occasionally wondered why some people switched from being semi-illiterate to being able to put words into a properly formed sentence. This post explains it. They were quoting random bits of Crichton verbatim. (These same people make no more sense quoting Crichton than when they use their own words.) I'll now have a reference to check. -
Chris G at 05:54 AM on 8 February 2011The 2010 Amazon Drought
Eric, I think we may have misunderstood each other. You cited a reference that infers a link between the droughts and the variability of ENSO. I wasn't sure what connection you were drawing, but most commonly I've seen skeptics use ENSO in the context of a pre-existing variability, and inferring that is all there is occurring now. I was countering by pointing out that El Ninos are getting warmer, in the sense that yes, there are waves, but that doesn't mean the tide isn't rising. And the energy for this extra warmth has to come from somewhere; it isn't produced by the water itself. Since you Also, I think our interpretations of "...we cannot attribute the recent ENSO shift..." might be different. I think they mean that their research was on how the shift in SST patterns affect rainfall over land patterns, and not directly on the causes of the SST changes. The research of others that they read was ambiguous on the matter; so, they are simply stating that they are not taking a stand on that aspect. I get the impression that you think they mean something more like, "..recent ENSO shifts can not be attributed...", which would be something else entirely. In any case, we know humans are changing the thermodynamic properties of the earth, and ENSO, winds, and rainfall are just means of distributing energy within the earth system. So, it would be silly to think that we aren't changing the pattern of when, where, and how much it rains. This study of the Amazon is just a quantification of the symptoms to date. -
muoncounter at 05:52 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
#30: "no measurable, testable, empirical difference" Both redundant (empirical = measurable and tested) and incorrect. The 'difference' is obvious to those who can open their eyes and see the red line at the right-hand end of the graph.
The 'natural cycle' should be sending temperatures lower. Measurements show temperatures are increasing. Hence that natural cycle isn't driving any longer. Your argument vanishes.
This is the science and it's really not that difficult; it's actually harder to cling to the 'no it's not' philosophy.
-
JMurphy at 05:48 AM on 8 February 2011CO2 lags temperature
PS The above paper has already been seen-off in the following Skeptical Science thread : The Dunning-Kruger effect and the climate debate Perhaps that would be the best place for any replies or further discussion, especially comments that would highlight that effect ? -
JMurphy at 05:44 AM on 8 February 2011CO2 lags temperature
Well, rather than go round and round in circles once more, all I have to do to kill two birds with one stone (so to speak) is this : 50 YEARS OF CONTINUOUS MEASUREMENT OF CO2 ON MAUNA LOA, by Ernst-Georg Beck, ENERGY & ENVIRONMENT, VOLUME 19, No. 7 2008 (I can only find the full paper on ICECAP.US, so I won't link to it) (Note also that I have copied the title, etc. straight from the source - I am not shouting !) The above paper suggests that CO2 levels were 400ppm in 1942 (i.e. they were higher than they are now), and this paper appears in a certain little list. Now, does this mean that CO2 lags temperature, according to this particular paper ? Or has CO2 been falling while temperatures have been rising ? Or temperatures will soon be falling, to follow the so-called fall in CO2 since 1942 ? Or what...? Can we trust this paper or anyone who uses it to try to claim...whatever they're trying to claim ? -
Daniel Bailey at 05:44 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
@ garythompson (39) and apl50 (41) This has been looked at before, in great detail, by very sharp and knowledgable minds:Only the anthropogenic contribution completes the picture, explaining the warming we can empirically see and measure in the absence of other forcings. Else we would be measuring a decades-long cooling trend. Which we aren't. -Edit-: Dana's comment below reminded me I forgot to source my graphic above (yes, Meehl et al 2004). My bad. BTW, Meehl has an extensive publication record (listing here). -End Edit- The Yooper
-
Bob Lacatena at 05:41 AM on 8 February 2011Articgate: perpetuating the myth that Arctic sea ice has recovered
John Cook, The light blue oscillating "monthly ice extent" in Figure 2 is I think too light. I didn't even notice it when I first looked, and to me it's the most important part of the graph. It's the orchard, that makes it very clear from whence the cherries were picked. Interestingly, they're not even max extents, but obviously very arbitrarily chosen matches. Could you darken that color? May make it royal (dark) blue, and instead make the currently royal blue yearly average black). -
MarkR at 05:38 AM on 8 February 2011A Flanner in the Works for Snow and Ice calculations
#35: A bigger Y means that you 'need' less warming to re-establish equilibrium. Bigger Y means less global warming, yes. But make sure you track the sign, positive feedbacks reduce Y and people flip signs in the equations regularly. So long as you're consistent it's not a problem! Assuming Y is constant (which it will be for small changes within a stable regime) then if F slows down its increase, then temperature rise will slow. In the real world we expect accelerating temperature increase because whilst CO2 forcing is logarithmic with concentration, concentration has risen faster than exponentially with time. Even if it was 'just' exponential then you would expect accelerating global warming because the time taken to return to equilibrium doesn't increase at the same rate as the final expected warming does. -
How We Know Recent Global Warming Is Not Natural
apiratelooksat50 - "Are you stating those forcings are not factors now?" Strawman argument! Please read the topic and discussion on CO2 is not the only driver of climate. CO2 accounts for most of the temperature change of the last 50 years, but not all. Nobody has claimed otherwise. Again, the question is one of evidence. There's plenty of evidence that our CO2 emissions are changing the situation, and no evidence that undefined "natural cycles" are doing so. The well defined and understood natural forcings and cycles cannot account for recent climate behavior - natural forcings plus our greenhouse gases do. Claiming these undefined, untestable cycles are responsible, rather than well established physics, is the equivalent of claiming it's leprechauns or (as I have phrased it), the lawn gnome Illuminati. It's quite irresponsible. -
Dikran Marsupial at 05:29 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
apiratelooksat50@37 wrote "Before I formulate a hypothesis, can you state your hypothesis for AGW?" I did not ask you to formulate a hypothesis, I asked you to provide an example of an observation that would falsify the hypothesis in Dr Spencers challenge that you asserted to be valid in post 25. I am mainstream on AGW, my view is in accord with that presented in the IPCC WG1 scientific basis report. "Also, are you of the position that only CO2 from human combustion of fossil fuels is the driving force? " No, the IPCC don't make such a claim and neither would I. -
apiratelooksat50 at 05:23 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Gary @ 39 I think we agree with each other. The natural forces didn't just go away because humans and fossil fuel combustion showed up. And, CO2 whether from humans or the Earth contributes to the greenhouse effect. So, yeah, they most certainly could be coupled. -
RSVP at 05:10 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
"For example, some scientists have studied the climate response to recent large volcanic eruptions, which can have a measurable impact on global temperatures." ...and these caused abrupt cooling over the course of just a few years. Somehow, animal life adapted and survived these abrupt "natural" changes. -
garythompson at 05:09 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Conversely, if one generates an hypothesis that is impossible to disprove because it is all encompassing that doesn’t mean that the hypothesis is true. If I propose that leprechauns are causing increased snowfall, decreased snowfall, increased drought, increased floods, higher temperatures, colder temperatures, melting sea ice, increased number of hurricanes (but only in some places), tree ring divergences (only in the north), increased species extinctions (everywhere), rising sea levels, changes in cloud cover (increased and decreased), etc. then it would be hard to prove me wrong. you have to admit that there should be some research showing how natural forces are at least coupling with AGW to produce the warming. Are we afraid to ask the question? -
WheelsOC at 05:01 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
I pointed out when his challenge hit WUWT that it's somewhat underhanded for Spencer to demand only peer-reviewed literature to use against him when he refuses to even attempt publishing in peer-reviewed venues anymore. Refereed letters journals like Geophysical Research Letters (the only outlet he chooses besides his own website) are not sufficient by themselves as a platform to credibly fight off full-fledged papers in Science or Nature. I also mentioned that Spencer himself has obligations to live up to in establishing the validity of his own "null hypothesis" if he wants to play the game. -
apiratelooksat50 at 05:01 AM on 8 February 2011How We Know Recent Global Warming Is Not Natural
Dikran @ 27 Before I formulate a hypothesis, can you state your hypothesis for AGW? Also, are you of the position that only CO2 from human combustion of fossil fuels is the driving force?
Prev 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 Next
