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16 ^ more years of global warming
jyyh - Given that the AMO (definition here) is a detrended sea surface temperature of the northern Atlantic, it's hugely correlated with global temperatures. Tamino discusses that here; if you look at the difference between northern Atlantic SST and GISTEMP trends, it's not terribly useful:
Global temperatures are really the cause, not the effect, of most of the AMO. Further evidence to this end comes from looking at lead-lag relationships (here's another Tamino post on this), where analysis shows a somewhat stronger correlation with AMO lagging temperatures by a month or two - and a negative delay is a very strong argument against causality. ENSO, by comparison, best correlates with an ENSO leading by 4-5 months, the correct causal direction.
If you attempt to relate AMO to global temperatures, there is a tendency to actually be subtracting the signal from itself, which leads to some very unrealistic estimates of climate sensitivity.
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The PDO may have some influence on global temperatures, but quite frankly we (a) don't have a huge amount of data, and (b) the duration and strength of observed PDO changes don't scale to the rapid and large temperature changes of the last 150 years. I suspect (IMO) that the PDO is at most a minor influence.
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MA Rodger at 00:06 AM on 24 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Bob Loblaw @21 & JasonB @22. The UK Tory party's leader election process is a little odd. It still has the same rules that saw Thatcher unexpectedly ousted as Prime Minister in 1990. That took just 14 days. The rules allow a vote of no confidence in the leader by Tory MPs if 15% of them call for it (and the call is an anonymous one). Losing the no-confidence vote results in a party leadership contest. For the Tories it matters not that the leader is also Prime Minister of the country. To win the leadership you need 50% of the vote of Tory MPs and if that is not achieved, the least successful candidate is eliminated and the vote re-run. Due to tactical voting and backroom deals, this system can throw up unexpected winners like John Major and Iain Duncan Smith. Remember Cameron was far from being the front runner in 2005. If it wasn't for the coalition partners, Cameron today would be very vulnerable to a challenge from the growing number of his dissatisfied right-wingers. Then again, if the coalition agreement didn't bind Cameron's hands, he may well have done a lot more of their bidding including reversing the UKs GHG policies.Moderator Response: [PW] All interesting, folks, but maybe we can steer this back to the topic of the post? Election processes are good to know about but perhaps this isn't *quite* the correct venue to elaborate a lot further on that subject. -
jyyh at 00:03 AM on 24 January 201316 ^ more years of global warming
imho the AMO (and PDO) indexes should be incorporated in areal predictions. it's still imho possible that they are representations of an 'ocean harmonic' with the approximate periods they suggest. is there a third hithero unnoticed ocean index that would fall in between AMO and PDO peaks making these negliglible in the whole system of global heat balance? (the missing heat problem comes to mind, though that was largely solved). i'm also curious of the possibility of such a long period oscillation but thus far haven't found any detailed temperature records for the last 1000 years that would be necessary to state there is a long period harmonic in the ocean. maybe it is just the variations in aerosols (use of unleaded lowsulfur gas f.e.) that makes the 20th century reconstruction hard. One can use log CO2 instead of linear assumption, I've seen that done somewhere (it was probably someone commenting on Tamino) but I don't remember when and did he take things mentioned by Tom and Kevin into account. Of long records, I tried once to create a volcanic record for the last 1000 years but there was a snag in the Carbon dating system and I've still not corrected that. -
Tom Curtis at 00:02 AM on 24 January 201316 ^ more years of global warming
Dikran Marsupial @92, a linear function is a reasonable approximation to the rise in CO2 forcing only since about 1970. Taken since 1850, it overstates the rise in forcing significantly up to then, and significantly understates it thereafter. The following shows HadCRUT4 plotted against 0.5 times CO2 forcing, ie, a transient climate response of 1.85 C per doubling of CO2:
For what it is worth, this crude model shows a strong correlation to global temperature rise over that period, with an r^2 of 0.754. The slope of the scatter plot of observed vs predicted temperatures is 0.72, indicating temperatures have risen faster than is predicted by this model:
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Dikran Marsupial at 23:35 PM on 23 January 201316 ^ more years of global warming
@curiousd As CO2 is rising approximately exponentially with time (which is I suspect responsible for the near constant airborne fraction), there isn't a great deal of difference between taking radiative forcing to be logarithmic in CO2 or taking it to be a linear function of time. Note also the 2 degrees C per doubling CO2 will be an estimate of transient climate sensitivity and that equilibrium climate sensitivity will be higher. -
curiousd at 23:26 PM on 23 January 201316 ^ more years of global warming
Tom Curtis, Thanks for comments! IMO the log CO2 is an improvement on the assumption that AGW is linear with time, especially going back to 1875. If you try to fit a logarithm with a straight line it does not work well. Is it better to assume linearity, and limit data to a really short time period, then fit that with an AMO index, or assume Log CO2 and take advantage of the longer time period and not try to fit something that depends itself on the AGW trend? (BTW the Berkeley Earth folks do use a log fit to their long term temp data). It is not clear to me that the short time period choice is better, and at the same time I anticipate that the paper by Zhou and Tung will become one of the main denialist staples. If it is o.k. I will post my two curves here and see what people think. -
jyyh at 23:25 PM on 23 January 20132013 SkS Weekly Digest #3
It looks like the koeln university predicts the southern Greenland melt of 2013 is under way. Also the SSW (sudden stratospheric warming) event up in the stratosphere might be worth of note (not common in winter).
Ice circulation this winter has been stronger than usual, likely much of it is still (in january) because the melt extent last summer. At least in the Baltic, only when the temperatures start to warm up for the spring the last of the leads close. Anyway
the circulation pattern has been unusual. If there was no GW, that sort of circulation would have been interpreted as building thicker ice, but this year there are still places
where ice may expand I doubt this is happening.
OK, now that I learned this image stuff (again) I'll try to link outside: 'Wipneus' @ Neven's Arctic ice blog has done a great job in extracting ice volumes (from the Piomas model), gridding and extrapolating to (what may be Maslowskij's style) zero. If the extrapolation 'holds water' the result is rather notable.
Much talk there, some going over my head. Anyway here's the image (let's see if it sticks)
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Kevin C at 23:07 PM on 23 January 201316 ^ more years of global warming
To add to Tom's point, a more sophisticated version of the same calculation would be to use the 2-box model with a full set of forcings. This can give you a TCR estimate directly. However I still don't think you would have a publishable result, for the simple reason that the result is totally dependent on the uncertainties in the forcings. You can get pretty much any answer you want. This type of calculation is useful for understanding the likely contribution of different forcings and it can provide a link between uncertainties in the forcings and uncertainty in TCR, but it cannot give us a absolute answer. It is an interesting and useful tool, but only when used within its limitations. -
Tom Curtis at 20:13 PM on 23 January 201316 ^ more years of global warming
curiousd @88, I do not know whether or not the used of digitized data would be a bar to publication, but the use of just log CO2 as the only forcing probably would be. It is well known that there are a number of forcings in addition to CO2. By most analyses, the CO2 forcing has been approximately equal to the sum of all anthropogenic forcings, with negative forcings (aerosols) approximately balancing other well mixed greenhouse gases. However, the uncertainty on the aerosol forcing is large, so that balance is not guaranteed, and nor will it be exact at all times. Consequently, while the use of log CO2 is useful for teaching, it is doubtful that it is useful in a publishable result. One small point, the 2 degree C per doubling of CO2 calculated equates to the transient climate sensitivity rather than the equilibrium climate sensitivity. There is significant variation in the ratio of TCS to ECS in models, but the central estimate is around 0.66, suggesting an equilibrium climate sensitivity of about 3 C per doubling of CO2 from your analysis. -
curiousd at 19:20 PM on 23 January 201316 ^ more years of global warming
I have now done the following: 1. Went to Zhao and Tung again. At one point they show a graph where they have regressed volcanos, solar, ENSO from temperature. I digitize this graph using online manual digitizer. 2. I look up Law Dome and Mauna Loa CO2 and correctly plot the temp, as digitized, versus log Conc/Conc 1875 as Zhou and Tung should have done. 3. Straight line fit yields C.S. of close to 2 degrees C per doubling CO2. (Not small C.S. Zhou and Tung get). 4. I subtract the straight line fit from their temperatures to yield a plot of temperature versus year showing three peaks about 70 years apart. We at present appear to be on top of the last, and smallest, of the three peaks. Question:(a) I think in principle this result is publishable, but it is based on digitizing someone else's result. I have published considerable in - say - Phys Rev, but not climate journals. Is the fact that I used digitized data going to be a killer? (b) If consensus answer to (a) is "forget it" would anyone here be interested in collaborating, someone who knows how to regress volcanoes, ENSO, which I do not? -
jyyh at 15:13 PM on 23 January 2013New textbook on climate science and climate denial
Congrats, John Cook! You'd be the 2nd person I know who has his name on the cover of a Springer book. Did someone from Springer ask you to write this? It looks like it handles the subject very broadly 'Pliny the Elder', 'History of Science'??? There are definitely chapters in there I'd need to read in order not to make a fool out of myself in scientific discussions. I've no influence on what the local university does in it's library, though I've got a couple of friends who might have. Unfortunately one is a mathematician, and the others ecologists. One of them might have good contacts to physics dept, though. I believe the Enviro intro classes still go by the classic 'Understanding the Forecast' by David Archer, but I'd have to ask about that. -
JasonB at 14:46 PM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Tom @17, a much closer approximation would be no electoral college and the majority leader in the House of Representatives is the head of government (Prime Minister) instead of the President, and the secretaries (ministers) are all members of Congress and appointed by the majority leader. (The minority leader would be called Leader of the Opposition, and he would in turn appoint "shadow ministers" who are responsible for keeping an eye on the corresponding minister.) The head of state would still be the President (Queen or Governor General, depending on country) but the role is not a political one, more symbolic (but with reserve power that is rarely exercised). The key difference with this rather than the electoral college is that those choosing the leader are (usually) politicians who's political future depends on the success of their choice, so being Prime Minister is a much more precarious position that can be revoked at any time (as happened to Australia's Prime Minister a couple of years ago) if the members of the ruling party get nervous about their political prospects at the next election. Different parties can have different rules about who gets to vote for the leader of their party and when but members of the party who have been elected to parliament is very common. (The Australian Democrats elected their leader on a popular vote of all party members, if I recall correctly.) The House of Representatives can also effectively dismiss a PM at any time by passing a motion of no confidence. (Technically, the person picked to become PM is the person who convinces the head of state that they can survive motions of no confidence, which would naturally be the leader of a party that happened to have a majority in the House of Representatives but can also be a minority leader if they can get enough other MPs to agree not to support motions of no confidence, such as the current Australian PM.) -
Bob Loblaw at 14:08 PM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Tom@17: ...well, in Canada the executive branch (cabinet ministers) also need to be selected from the MPs (elected) and senators (appointed), and the governing party almost always has a majority in the House, so you don't get the dysfunctional US pattern of a President without support in Congress, and when the government doesn't have a majority the whole government can fall on confidence motions, giving the electorate another chance without having to wait until the normal end of term. And having more than two parties gives more choice, and less polarization (although we're working on that). ...but other than that, pretty much the same. -
calyptorhynchus at 13:10 PM on 23 January 2013New textbook on climate science and climate denial
What does the second volume cover? I can persuade my institution's library to buy vols 1 & 2, but only if the second volume has coverage of the health impacts of global warming. -
Mikemcc at 11:43 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
I have submitted a message to his official communictaions site. I would advise others to do so, but please keep it very polite, we don't want to stoop to the lows of the more outragous deniers! Official Communications site -
Mikemcc at 11:20 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Increased winter precipitation is even mentioned! "Hotter and drier and warmer and wetter The summers are set to get hotter – by an estimated 1.6°C in the 2020s and 2.7°C in the 2050s. They are also getting drier – by an estimated 7% in the 20020s and 19% in the 2050s. The winters by contrast will get warmer and wetter – 6% wetter in the 2020s and 14% in the 2050s. In London we face three major challenges as a result of this changing climate and weather: •flooding •drought •heatwaves. To ensure we stay on top of the threats, we are responding to each challenge with a set of management measures that form part of the London Plan. LinkModerator Response: [PW] Hot-linked reference -
Mikemcc at 11:17 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
His comments don't even fit in with his official policy! “London has an unrivalled opportunity to benefit from the shift to a low carbon economy. The time for trials and experiments is over - we are putting in place large scale programmes that can deliver significant CO2 reductions and billions of pounds of energy savings.” Boris Johnson, Mayor of London http://www.london.gov.uk/priorities/environment/climate-change -
Sceptical Wombat at 10:13 AM on 23 January 2013New textbook on climate science and climate denial
As far as content review is concerned it is worth noting that Salby has published a textbook which includes his theory that the increase of CO2 in the atmosphere is not driven by human emissions. So far he has been unable to publish it in a peer reviewed journal. Of course this is a very small part of a text book that is presumably otherwise accurate. -
Sceptical Wombat at 09:45 AM on 23 January 2013New textbook on climate science and climate denial
I intend to recommend it for my local library. My experience in the past has been that they almost always buy books I recommend - though this one may prove a little pricey. The advantage of doing this is that as well as getting to read it you make it available for other readers. -
Tom Curtis at 09:18 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Bob Loblaw @16, in other words, it is pretty much the same as the US system, except the "electoral college" gets to hang around and be the legislature. -
Bob Loblaw at 09:06 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Phil, Shoyemore: Oh, I agree that the Queen doesn't really have much choice. In Canada, it's the Governor-General that doesn't have much choice. The only time it gets interesting is when one party doesn't have a clear margin of seats, or has lost a confidence vote shortly after an election, and there is a question of coalitions or PMs from the non-leading parties. Then you get the constitutional lawyers arguing about precedents, the pundits pretending they know more than the lawyers, and the public wondering what it's all about. The point is, there isn't an election for Prime Minister. You get elected to the house as an MP, not a PM, and you get chosen (maybe "elected") by your party to become leader. If you become leader of an opposition party, then people can elect your MPs in the hope that you'll become PM. If your party already forms the government, then you can become PM by being chosen as leader, even if the people never had a say. -
shoyemore at 08:40 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Bob Loblaw #13 The British have an unwritten Constitution, or accretions of tradition over the the years. The day when the Monarch could independently choose the Prime Minister are long gone - now the outgoing PM (one who has lost the Party leadership, lost an election, retired or lost a vote of confidence) "advises" the Monarch on whom to call to form a Government - always the leader of the strongest party in the House of Commons. Boris is an eccentric, an endearing one, a true original, but I think pretty shrewd on the inside. He has made quite a competent Mayor of London, and he surely must be looking for his next career move. I think this is a false step on his part, but he might undo it with a brilliant speech somewhere on science. He has been contradictory in the past. I think you are right in that this is not really for public consumption, but a politician saying to a group of potential supporters "I am one of you". Bit off-topic I suppose, but when an ambitious politician starts sounding off on climate, then look out. There is more going on than meets the eye. -
Bob Lacatena at 08:29 AM on 23 January 2013New textbook on climate science and climate denial
What are the chances that I can convince my daughter to take a course that uses that as the text? Then I can inherit her copy... :) -
Phil at 07:56 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
"The PM is chosen by the Queen" In theory, but not in practice. This provides a good explanation. -
rockytom at 07:28 AM on 23 January 2013New textbook on climate science and climate denial
I would like to thank all the readers to this point who have commented on the above textbook. I will contact Springer about releasing a soft-cover version at a reduced price in the near future. I am a firm believer in the "Henry Ford approach." Having worked closely with John on the above textbook, I agree that there must be more than one "John Cook" related to this site. His posts and other works are first rate and he even has time to work toward his Ph.D. GTF -
LarryM at 07:06 AM on 23 January 2013New textbook on climate science and climate denial
My friend the Professor is interested in the book for a possible forthcoming course on climate science, but even for students the price is a barrier because her students are not wealthy (this is a factor with other textbooks too). I imagine Springer has done the research and the math, but I wonder if they ever consider the "Henry Ford approach", namely sell them cheap enough that lots of people will buy them. After looking at the contents I definitely want the book and might even shell out $100 for my own personal consumption, but I've also been discussing another possibility that I'll mention here in case anyone finds it useful. Get together with one or more people and share a book, even a person on the other side of the country or the world because mailing is pretty cheap. The downside is that I'd want to end up with the book to have for reference, plus I'd want flexibility about when and how fast to read it. Anyway, it's just a thought... -
Rob Honeycutt at 07:00 AM on 23 January 2013New textbook on climate science and climate denial
Is there a Cliff Notes version? I say that in jest, but there is a need for a very short version of the same thing. Sort of a pocket climate science, for the general public. -
Bob Loblaw at 06:46 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
dana and shoyemore: Keep in mind that the process of becoming Prime Minister is not at all like the process of becoming President. The PM is chosen by the Queen - traditionally, the choice is the leader of the party with the most seats in Parliament. It is up to the party to choose the leader they want, and if Britain is like Canada, it is up to the party to decide how that selection process works. My understanding is that British parties usually used to leave selection of the leader up to the sitting MPs in the party, which could lead to some quick switches to a new PM when the old one retired. (In Canada, traditionally parties held a huge national convention, with delegates elected from each riding. These days, parties are moving towards a direct vote of the membership.) -
scaddenp at 06:25 AM on 23 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Kevin - please do. I am slowly getting stuff installed on new PC and that would be interesting to have. -
Slioch at 05:59 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Dana I've posted the text of your message on the Telegraph website following the Boris Johnson article, here. It will probably get rapidly buried by other posts, but will at least alert a few to SKS. I thing it is the case that the UK Conservative party, which is signed up to acceptance of the scientific position on global warming, is getting increasingly worried by UKIP (UK Independence Party) whose main stance is in favour of the UK leaving the European Union, but which is also in denial about AGW. So, my reading is that Boris, who is Conservative Mayor of London, has been asked to make these sort of comments so as to slow the loss of support from the Conservatives to UKIP. Boris is a maverick, and something of a buffoon, so if his statements prove problematic for the Conservative Party they can be dismissed, whilst still giving the impression that there is room within the Conservatives for fruitcakes who dismiss the science on AGW.Moderator Response: [PW] Hot-linked Telegraph website URL -
shoyemore at 05:56 AM on 23 January 2013New textbook on climate science and climate denial
I looked up the Table of Contents on Amazon and it looks wonderfully thorough and enlightening. Well Done. My only concern has to be the price. With several climate books on my shelves, shelling out 89 to 90 euros is quite steep, especially as SkS is readily available! Any chance of a paperback edition? Is the target audience the academic community? It does not seem the type of book that will attract your ordinary "popular science" reader.Response: [JC] The target audience is college undergraduates (well, more specifically, college professors teaching undergraduate courses who adopt our book as course material). Unfortunately price is out of my control :-( -
Doug Bostrom at 05:22 AM on 23 January 2013New textbook on climate science and climate denial
This just lends credence to my theory that there are several John Cooks working in closely-spaced iterations of the multiverse, with leakage. -
DaneelOlivaw at 04:28 AM on 23 January 2013Was 2012 the Hottest La Niña Year on Record?
Is interesting to see the 0,16 ºC/decade figure appearing so often and using different methods to filter short term influences from the global temperature data. To me it looks like a fairly robust result. Just one nitpick, would it be possible to have some error bars in those trends? -
MA Rodger at 04:10 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Boris Johnson has made a political career of courting maximum publicity while sending mixed messages. Is he the affable fool or should some part of what he says or does be seen as a the true Boris, a calculating and focused campaigner? This recent Op Ed is not the first time he has made climate denier noises. Last year, for instance, he staged 4 events to discuss 4 imperatives facing London. One of these was The Environmental Imperative. "The question of the environment is often described as the most significant challenge faced by the planet today."" So who gets asked to provide the Key Note speech? One Matt Riley, one of the GWPF crowd. You can see the slides of Riley's presentation here and then ask if Boris is a fool, a dyed-in-the-wool denier, or a consummate politician buttering up the right-wing tories. It makes for an interesting question. -
CBDunkerson at 03:39 AM on 23 January 2013New textbook on climate science and climate denial
danp, I can't speak for this book, but I know from personal experience that the degree of review for textbooks is usually entirely up to the publisher. When I worked for Simon & Schuster many years ago most textbooks would go out to just two or three 'content reviewers' while more than a dozen people poured over layout, spelling, grammar, presentation, et cetera. Basically, if there weren't any obvious errors the content would be approved. Other publishers might not check accuracy at all. Springer is a large and fairly well known publisher, and thus I suspect that maintaining their reputation is an important part of the business model. Thus, some sort of content review seems likely, but I doubt it would be as detail oriented as scientific peer review. Of course, textbooks also tend to cover 'settled' issues rather than cutting edge new research. -
LarryM at 03:09 AM on 23 January 2013New textbook on climate science and climate denial
Congratulations on the fruits of what must have been a great deal of effort! Hopefully SkS visitors will send a link to this article to instructors/professors of climate-related classes whom they may know (I'm doing so now). It's unfortunate that introductory-level textbooks like this are too pricey for a more general audience, because we desperately need more widespread knowledge about climate science in order to make progress on actually mitigating climate change and leaving the next generation a tolerable planet. Thanks for this good work! -
danp at 03:08 AM on 23 January 2013New textbook on climate science and climate denial
I am a long-time reader of this site and find it invaluable for solid, scientifically valid, information. Thank-you. I do have a question regarding the textbook described above. In general, this site (correctly) places a great deal of importance on the peer-review process for papers presented in the technical literature. Could you please explain what kind of review a textbook such as this receives before publication?Response: [JC] My experience with the publishing of this textbook matches that described by CBDunkerson. Springer reviewed the textbook and provided very detailed feedback on required changes to the content. My impression is that it is detailed although not as rigorous as peer-review where a paper is focused on a single topic and reviewers would be experts on that topic. In this case, the textbook is multi-disciplinary and such focus on a single area is not practical. -
shoyemore at 02:49 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
dana1981 #9, After reading Leo Hickman's article, I think that speculation may be correct. The Tory right are nervous about Europe and immigration, and they have the farther-right United Kingdom Independence Party on their case, threatening their turf. The UKIP once had Christopher Monckton as its Deputy Leader! It is more about publicly attacking renewable energy, especially wind farms, an issue with more public traction, than about climate change, but deniers they are. The Tory right-UKIP are a sort of British Tea Party, and Johnson is probably signalling to that wing of British Conservatism that he is willing to be their man. I see the influence of Lord Lawson (an ex-Tory "Grandee") of the Global Warming Policy Foundation in this also, but that is a guess. Politicians are always running for office, and this was more than an off-the-cuff comment by Johnson on the British weather. -
dana1981 at 02:19 AM on 23 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
shoyemore @8 - I've read some speculation that Johnson's comments may be an appeal to conservatives to help him win the PM nomination. But not being familiar with British politics, I don't know how accurate that is. -
Alexandre at 00:48 AM on 23 January 2013Was 2012 the Hottest La Niña Year on Record?
R. Gates at 07:25 AM on 22 January, 2013 Or maybe it could be done with monthly figures, and thus one would not have to categorize the years at all. I don't think it would change the main conclusions, though: under similar oceanic/volcanic conditions, anthropogenic warming rate keep on going. -
Kevin C at 00:27 AM on 23 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Klapper@33 For what it's worth, I've just rerun the Foster and Rahmstorf code using data up to 2012, including the volcanic forcings up to the end of 2010. The volcanic forcings after 2000 make essentially no difference. If you want to try it for yourself, say so and I'll put the code and data on a download site. -
pauls at 23:26 PM on 22 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Tom Curtis, Klapper - Aside from stratospheric aerosol forcing associated with volcanic eruptions, a number of studies have now noted an observed increase in "background" stratospheric aerosol scatter and suggested a likely source being anthropogenic SO2 emissions (Hoffman et al. 2009, Liu et al. 2012 Solomon et al. 2011 calculated an associated forcing for this increase at -0.1W/m^2 for the present compared to 2000, though that may include effects of volcanic activity too, with a possible further contribution of -0.1W/m^2 from 1960 to 1990. It should be noted that none of the CMIP5 (or CMIP3) models prescribe this increase in "background" stratospheric aerosols. Only one CMIP5 model (MRI-CGCM3) includes an online aerosol transport+chemistry module capable of moving SO2 emissions from the troposphere to the stratosphere and producing sulfate aerosols interactively in order to potentially simulate such an increase. This has been demonstrated in the model for transport of SO2 from volcanic emissions, but I'm not sure if it is able to do the same for anthropogenic emissions. -
Tom Curtis at 22:20 PM on 22 January 2013CO2 is plant food
Michael Sweet @20, Albrecht (50 years ago) showed that improved soil fertility results in: 1) Improved water retention in the soil, enabling plants planted in that soil to better resist drought; 2) Reduced water runoff during light and moderate rainfall, reducing the risk (but not the possibility of) flooding; 3) Cooler soil temperatures during the day, and no doubt warmer soil temperature at night - probably a result of improved water retention increasing the thermal capacity of the soil. These are, now, well known and uncontroversial results. Soilfertility, not Albrecht, now appears to claim without any support from Albrecht or independent evidence, that improving soil fertility is an adequate mitigation strategy by itself for the effects of global warming. He has previously appeared to claim that loss of soil fertility is in fact responsible for many of the observed consequences of global warming. Again, this is without evidence and certainly without evidence from Albrecht. Soilfertility's claims are, or course, without merit. He provides no evidence of wide spread loss of soil fertility, and modern farming practices attempt to improve soil fertility. Uncultivated land is unlikely to have either lost or gained soil fertility because it is in a near equilibrium state with its environment. Ergo, Soilfertility has no basis beyond mere assertion for any claim that the increased frequency of floods, droughts etc are due to a loss of soil fertility. Equally he has no basis beyond mere assertion for any claim that improving soil fertility would mitigate the effects of climate change. On top of that, his discussion is plainly off topic; repetitive and amounts for the most part to sloganeering. His wall of text quotation @18 probably does not violate additional comments policies, but is clearly contrary to the spirit of them. -
mspelto at 22:03 PM on 22 January 2013Was 2012 the Hottest La Niña Year on Record?
Well done Dana. Given the number of years in the record, three categories was just right for obtaining a meaningful comparison. Trend similarity is quite striking. -
michael sweet at 22:00 PM on 22 January 2013CO2 is plant food
Soilfertility: Are you serious when you suggest we should throw away decades of climate science based on a paper presented to a bunch of dentists in the 1950's??? You assert that these unreveiwed claims from 60 years ago are worth more than the considered opinion of thousands of scientists in the IPCC report? Why have no current soil scientists stepped to the plate with this data if it is so good??? Please provide an up to date citation or your basic point is useless. You are not being serious with your wild claims that a single scientist, who was not peer reviewed, in 1960 is right and everyone else is wrong. Provide current data to support your wild claims. -
shoyemore at 20:02 PM on 22 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Boris Johnson is a likeable figure, tipped to be Prime Minister one day, and it is a pity he has made a fool of himself in this way. Definitely, puts a damper on his ambtions, IMHO. William Connolley did an analysis of Piers Corbyn's forecasts a few years ago, and found he was no better than 50% correct in his predictions. Corbyn also refuses to publish his "model" for peer-review, and his reputation rests mainly on the hype he gets in the Daily Mail and Telegraph. Of course the "story" writes itself - "Maverick genius proves pointy-heads wrong". Well written, dana. -
Cornelius Breadbasket at 19:49 PM on 22 January 2013Open Letter to London Mayor Boris Johnson - Weather is not Climate
Please do send it to the Telegraph. -
Doug Hutcheson at 17:32 PM on 22 January 2013CO2 is plant food
Soilfertility @ 18, nothing in your post seems to support your claim that scientists are mistaken in any way about the effects of global warming. At last, though, you ask a direct question that can be answered:would the better approach to mitigate the damage caused by these problems be to lower the average temperature of the planet by reversing global warming or to figure out how to restore the lost fertility to the soil?
That's a no-brainer: lower the average temperature of the planet back to what it should be without our insane injection of greenhouse gasses into the atmosphere, by magically removing the excess of those gasses; that way we not only counter the effects on our soils, but also bring other systems back into balance (e.g: stop the acidification of the oceans). Second best choice: hold the current levels of greenhouse gasses, by drastically slowing our emissions. Why? Because we can repair soils in a suitable climate at our leisure, but we can do nothing about them in the climate we are creating. Putting fertility back into the soil will not save us from the future we are creating. -
jyyh at 17:14 PM on 22 January 2013Was 2012 the Hottest La Niña Year on Record?
The other effect La Ninas have achieved is the return of the sea level rise as David Appell succintly cherry-picks: Link. 18mm/year, AAAAAhhh, we're going to drown!! But I'd guess that the floods in various areas of the world will be less because of this.Moderator Response: [PW] Hot-linked reference -
JasonB at 15:33 PM on 22 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
I wrote:If they really did take the standard deviation of the respective differences, as they say, then there would be no point comparing the data to the true global land average first to compute the difference because the standard deviation of the respective differences would be exactly the same as the standard deviation of the original simulated data points, since it's just an offset.
Sorry, that's not quite true — I forgot that they were using 50 different "real" temperatures to compare against the 50 different reconstructed temperatures. In that case they would still need to compute the difference, but the rest of my point still stands: If they are actually computing the standard deviation of the residuals for each month, rather than the RMS, then they can hardly call that "Error". The RMSE is the same as the square root of (the mean error squared plus the standard deviation squared) so it nicely captures both the "uncertainty" and "bias", as Ed called them.
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