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Berényi Péter at 00:24 AM on 4 August 2010Why I care about climate change
John Cook wrote at 08:49 AM: Thousands died in record heat waves in Pakistan and India in recent months And tens of thousands in England because of the cold, each winter. Have a look at the Excess Winter Mortality page of the UK Office for National Statistics, please.
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Dikran Marsupial at 00:11 AM on 4 August 2010On Consensus
Re: nhthinker Loth as I am to do so, I am forced to point out that nnthinker is engaging a rhetorical, rather than scientific argument, in which I am not that keen on participating. DC is right, scientists do need to know about rhetoric; IMHO it needs pointing it out, but it is best just to stick to the science otherwise and not be drawn into the same tactics (I hope I have managed that here). For example, asking for an example of an accurate climate prediction "What is your iconic climate model prediction that has proven accurate by the test of time?" and then when some examples are given, replying "The advocates here seem to fall into the fortune teller's trap. There will always be some accurate prediction of of future events, especially when you have thousands of predictions to choose from. Which rather transparently shows that there was little genuine interest in the answers. There is certainly an element of "having your cake and eating it as well". There is also the point that I have explained more than once that "90% correct is a meaningless term, and nhthinker is still using that term and has not attempted to engage in the point that the internal variability of the climate means that the accuracy of a prediction is not so easily measured as that phrase suggest. The quote from Gavin Schmidt is rather curious, in that in a couple of occasions it mentioned the internal variability ("weather noise") that I raised, here "The implication is that over a short period, the weather noise can mask significant differences in the forced component." and here "Given the noise level, a trend 75% as large, would still be within the error bars of the observation (i.e. 0.18+/-0.05), assuming the transient trend would scale linearly" In other words, the weather noise in the data is large enough over such a period that the model could be very different and still be consistent with the observasions (note it is the error bars of the obervaions he mentions, not of the models). The highlighted bit "Is this 20 year trend sufficient to determine whether the model sensitivity was too high? No." Doesn't say that the model is wrong, just that there isn't enough data to be confident of detecting an error (as the "weather noise" is too large). Which was pretty much what I was trying to explain. Regarding "Broeker's analysis was directionally correct.", that is a little disingenuous as he predicted global warming of 0.8 degrees over the 20th century, and the GISS data show a warming of about 0.82 (judging from the plot). I'd say that was rather more than merely "directionally correct".
If you want to know Gavin Schmidt's views, why not ask him? If you don't want to email him, you could always post a comment on RC marked "FAO Gavin Schmidt".
That will be my last response to nhthinker (chorus: phew! ;o) until he actually engages with the point that "weather noise" means that it is not possible to achieve an arbitrary level of accuracy, even if your model is perfect.
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werecow at 23:48 PM on 3 August 2010Why I care about climate change
I'm not a big environmentalist either, but I do take an interest and I have my share of concerns. That said, for me the reason for getting into this is mostly just my general interest in science, with a particular interest in topics where there are public controversies that don't reflect the state of science. In other words, I love learning new things and enjoy applying my skepticism. It's addictive. I've moved around between different topics in skepticism and my main focus until recently had been on evolution theory, but climate change is an especially interesting case because it's one where you really do have to engage with the material to see through the more sophisticated arguments. It highlights a general problem in skepticism, that it's not always clear to a layman where to draw the line between genuine skepticism and contrarianism. And the debate is so highly politicized that you don't always know who to believe, or whether you can believe anyone at all. But figuring out things like that is what skeptics do best, after all. Plus, as I started reading up on the material, I realized I had been mislead about both the reality and the potential severity of the problem myself. I have to admit, that kinda pissed me off. I don't like being bamboozled, so now I'm trying to learn as much as I can, get a solid foundation, and perhaps push back just a little bit when appropriate. I'm still trying to determine where exactly that line should be drawn, but I'm learning a lot of interesting things about climate science, so at least I'm enjoying myself. -
CBDunkerson at 23:40 PM on 3 August 2010Why I care about climate change
Poptech #52 Seldom have so many laughable ironies been condensed into so few words. I salute you sir. -
chris1204 at 23:22 PM on 3 August 2010Grappling With Change: London and the River Thames
Britain's tides have a noble history - Julius Caesar's first invasion of Britain in 55 BCE was majorly disrupted because his navy could not cope with North Sea tides. Following up from HR's post, I note the link suggests subsidence may also be a problem as is often the case with 'reclaimed' lands. Reclaimed lands are especially vulnerable especially if there's extraction of artesian waters - eg, Venice or Mexico City (which is built on what was once a lake). Meanwhile, major parts of Scandinavia (eg, Norway) are still uplifting following the melting of the ice (while other areas such as Denmark conform more to the estuarine floodplain model). I guess it's all complicated and needs to be looked at on a case by case basis (which is not the same as complacency). However the whole AWG business plays itself out, our concern should be above all for the losers as opposed to a casual winners and losers shrug of the shoulders. I enjoyed this article which highlights in a concrete and immediate way important philosophical questions facing a city we take for granted. The historical backdrop makes it all the more fascinating. Hardly anyone today would think of burying their stock of cheese in the face of catastrophe - we take so much for granted these days in our relative prosperity. Pepys, what's more, was a wealthy man in an influential position. A bit off topic but Pepys' decision to bury his cheese brings to mind a story from my father's life. He managed to get away from what was then Soviet occupied Poland in 1940 to spend his adolescence in Greece under German occupation in a time of famine. His first suit cost three loaves of bread. He was lucky but he does look very skinny in photographs from that time. Similarly, my father in law spent his adolescence in Shanghai (having also managed to get away from Poland in 1939 ahead of the German army). His whole family (four adults plus an adolescent boy) occupied a single room in the Jewish ghetto in rather straitened circumstances. They still employed a Chinese maid. One can only imagine her poverty. It's a calculus difficult to imagine yet it formed part of the lives of real people who right up till 1939 also took their prosperity very much for granted. -
Arkadiusz Semczyszak at 23:03 PM on 3 August 2010The Past and Future of the Greenland Ice Sheet
@Chris - We refresh “a little bit” of literature - references: A. Regarding MIS 11: Sea level 400 000 years ago (MIS 11): analogue for present and future sealevel?,Bowen, 2010; and: Comment on D. Q. Bowen (2010); by Hearty, 2010. B. Most global causes of melting ice in Greenland: Millennial scale climatic variations and bipolar seesaw pattern, Capron et al., 2010: “NorthGRIP records enable us to depict the sub-millennial scale variability during the GIS of MIS 5 and thus, to highlight new type of features (GIS 21, 23) observed also during MIS 3 (GIS 11, 12, 13–14, 16). These new patterns appear as (i) precursor-type events prior to the onset of GIS (ii) rebound events at the end of GIS and (iii) centennial-scale cooling during the long and warm GIS 24. In addition to the internal forcing of ice-sheets on the climatic evolution during these events, we have proposed the external influence of the summertime insolation at 65 N. [!] Disentangling the main processes leading to these sub-millennial scale structures (ice-sheet, insolation, sea-ice, and hydrological cycle forcing) will require dedicated modelling studies. Through our results, we assume that orbital-scale variations play a role in rapid climate change but, also, the millennial-scale variability may hold clues to the long term climatic changes (i.e. Weirauch et al., 2008; Wolff et al., 2009b). Comparing Antarctic and Greenland behaviour over the succession of AIM/DO back to MIS 5 provides a more complete description of the bipolar seesaw pattern. As expect from the bipolar seesaw concept, a linear relationship between AIM amplitude and preceding GS duration only holds for shorter events, while for extraordinary long GS a new heat flux equilibrium between the Northern and Southern Hemisphere is obtained (EPICA c.m., 2006, Stocker and Johnsen, 2003) and the Southern Ocean warming ceases. The conceptual model of Stocker and Johnsen (2003) for a thermal bipolar seesaw is able to represent most of the variability of the north-south relationship depicted in Greenland and Antarctic isotopic records, even at sub-millennial timescale. However, it is not able to depict the delay of Antarctic warming after the beginning of the GS during the periods associated with large ice sheets (i.e. during MIS 2 and the end of MIS 4). It shows that Greenland ice core temperature proxy records cannot be taken as direct proxy for AMOC changes as suggested from the conceptual model. To go beyond our description and the conceptual model of Stocker and Johnsen (2003), the new types of DO events identified during MIS 5 should be studied with more complex models (e.g. Ganopolski and Rahmstorf, 2001; Knutti et al., 2004). This would allow quantification of the influence of insolation, ice-sheet volume, sea-ice and hydrological cycle on sub-millennial-scale variability (precursor and rebound events). This should provide also a better understanding of the response of Antarctica to these types of events.” Influence of solar variability, CO2 and orbital forcing between 1000 and 1850 AD in the IPSLCM4 model, Servonnat et al. 2010: “With a signal-noise ratio (SNR) estimate we found that the temperature signal of the forced simulation is significantly different from internal variability over area wider than ~5.106 km2, i.e. approximately the extent of Europe. ORBITAL FORCING PLAYS A SIGNIFICANT ROLE in latitudes higher than 65° N [! - Greenland !] in summer and supports the conclusions of a recent study on an Arctic temperature reconstruction over past two millennia. [...] The forced variability represents at least half of the temperature signal on only ~30% of the surface of the globe. This study suggests that regional reconstructions of the temperature between 1000 and 1850 AD are likely to show weak signatures of solar, CO2 and orbital forcings compared to INTERNAL VARIABILITY.” Extreme deepening of the Atlantic overturning circulation during deglaciation., Barker et al., 2010: “We conclude that the rise in atmospheric CO2 concentrations and resultant warming associated with an especially weak overturning circulation are sufficient to trigger a switch to a vigorous circulation, but a full transition to interglacial conditions requires additional forcing at AN ORBITAL SCALE.” “The fact that [AMOC] can react in such a way is really exciting.” A team of researchers, led by Dr Stephen Barker from Cardiff University, has investigated how changes in a key component of global ocean circulation are related to significant changes in temperature, which have taken place IN THE RELATIVELY RECENT GEOLOGICAL PAST.” “But the researchers believe the link between the AMOC and DEGLACIATIONS OVER THE LAST HALF A MILLION years is too strong to be a coincidence. It looks like deglaciation may only happen when the AMOC shifts from weak to strong.” “And these changes can have extreme effects. During the Bølling-Allerød (B–A) warm phase, 14,600 years ago, temperatures rose by 9 degrees Celsius over the course OF JUST A FEW DECADES.” Natural forcing of climate during the last millennium: fingerprint of solar variability, Swingedouw et al., 2010: “Then, we focus on the regional climatic fingerprint of solar forcing in winter and find a significant relationship between the low frequency TSI forcing and the NAO with a time lag of more than 40 years for the response of the NAO. Such a lag is larger than the around 20-year lag suggested in other studies. We argue that this lag is due, in the model, to a northward shift of the tropical atmospheric convection in the Pacific Ocean, which is maximum more than four decades after the solar forcing increase. This shift then forces a positive NAO through an atmospheric wave connection related to the jet-stream wave guide. The shift of the tropical convection is due to the persistence of anomalous warm SST forcing the anomalous precipitation, associated with the advection of warm SST by the NORTH PACIFIC subtropical gyre in a few decades. Finally, we analyse the response of the Atlantic meridional overturning circulation to solar forcing and find that the former is weakened when the latter increases. Changes in wind stress, notably due to the NAO, modify the barotropic streamfunction in the Atlantic 50 YEARS AFTER SOLAR VARIATIONS. This implies a wind-driven modification of the oceanic circulation in the Atlantic sector in response to changes in solar forcing, in addition to the variations of the thermohaline circulation.” C. Conclusion: 1st Peak of the last high solar activity (the highest of approximately 8 thousand. years!) was in the 60s of the twentieth century - and thus 40-50 years emu ... ... after about 40 - 50 years will therefore save the Eskimo from “the shackle” of ice? 2nd So the present "unprecedented" melting of Greenland's ice is (mostly) the effect of natural changes throughout the NH, and not without significance here is my favorite LTC-LNO: The complex dynamics of the seasonal component of Earth’s surface temperature, Vecchio et al., 2010: “The dynamics of the climate system has been investigated by analyzing the complex seasonal oscillation of monthly averaged temperatures recorded at 1167 stations covering the whole USA. We found the presence of an orbit-climate relationship on time scales remarkably shorter than the Milankovitch period related to the nutational forcing. The relationship manifests itself through occasional destabilization of the phase of the seasonal component due to the local changing of balance between direct insolation and the net energy received by the Earth. Quite surprisingly, we found that the local intermittent dynamics is modulated by a periodic component of about 18.6 yr [... !!!] due to the nutation of Earth, which represents the main modulation of the Earth’s precession.”Moderator Response: Please reduce the lengths of quotes in your comments. Instead, summarize and provide links or citations to the sources. -
canbanjo at 22:59 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
Poptech, OK so you have added the word 'alarm' to the title of your list. I understand you are not questioning AGW evidence. I would still really appreciate it if you could identify the most persuasive papers that show that we do not need to be alarmed by AGW. Otherwise it is difficult to be convinced. Thanks -
JMurphy at 22:16 PM on 3 August 2010On Consensus
Another good model prediction here ("Quantifying the uncertainty in forecasts of anthropogenic climate change", 1999/2000), particularly Figure 3. This was referred to in a recent GUARDIAN article. -
OPatrick at 22:10 PM on 3 August 2010Why I care about climate change
John, it surprises me that anyone should need clarification of your reasons for writing on climate change - your passion, sincerity and integrity shine through in your posts and in your moderation and speak clearly of your underlying humanity. I'm an atheist and many years ago I'd have held your religion against you, but over the past couple of decades the growing realisation of the impacts of climate change has led me to re-evaluate my world view. I remember one particular epiphany came for me in the consumerist frenzy of pre-Christmas shopping in our city centre. I saw a bloke standing in the midst of the heaving hoards with a placard "God is Love" and realised I had more respect for him than anyone else around me. There is an undeniable connection between climate denialism and the religious right, particulalry in the US, but I believe this has little to do with religion. It is not their religion that informs their politics, but perhaps their politics that informs their religion? I am disturbed when I see someone arguing that we should not worry about climate change because God has given us the rainbow, but I have come to see that this is not the argument of religion, but using religion to make an argument. Climate change has also turned me away from being an environmentalist. When I was in my teens I was aware of climate change but had equal concerns for protection of individual species and forest environments. Now all these concerns are peripheral at best and it is the overwhelming human suffering that concerns me. I used to be staunchly, and probably ideologically, anti-nuclear, but now am only so on balance. My over-riding ethos now is sustainability. My children are of course a focus for this, but sustainability itself is the goal. I discover this in myself through a phenomenological approach. -
chris at 21:42 PM on 3 August 2010On Consensus
nhthinker at 21:08 PM on 3 August, 2010 Making too much of the comparison between the predictive abilities in medicine and climate science is pretty fruitless. One can address such comparisons but we should be much clearer specifically on what we are talking about. Your "fortune teller" jibe is way off base. If we consider models and their predictive abilities (and the Gavin Schmidt quote), we can be much more specific: We have a high degree of certainty that enhancing the greenhouse effect will cause the Earth to warm all else being equal, and have rather strong evidence based on analysis of historical [CO2]/temperature relationships that the climate sensitivity (equilibrium Earth temperature response to doubling [CO2]) is at least 2 oC. The most likely value based on our understanding is 3 oC and there is lesser likelihood that it is above 4.5 oC. Those values are pretty well constrained by a large body of evidence. Since climate models are parameterized according to our best understanding we are not surprised that they have so far done pretty well predictively. A major uncertainty (that Dr. Schmidt is referring to) is the various elements of the climate system, especially the oceans, which result in inertia in the response to forcing. Thus we have higher certainty about the amount of eventual warming, than the temporal progression of warming, although the reasonable success of current models (and even Broecker's 35 year old back-of-the-envelope calculation) indicates that we have a pretty good understanding of the essential energy balalnce of the climate system. One could argue that this compares favourably with many aspects of medicine. If one considers a diagnosis of cancer, for example, and considers an expert prognosis, the predictive elements are not a million miles from those involved in predictive climatology. The specialist may well have a high degree of certainty about the outcome (e.g. a cancer that is a high mortality), but will be less certain about the temporal progression of the response. S/he might be able to give 1 year, 3, yr, 5 yr chances of survival, but there will be a range of possible projections that involve interperson variability (genetics, lifestyle, personality) and other contingent happenings. Much in the way that the a climate projection might be completely scuppered by an unpredictable series of massive volcanic eruptions, so the medical prognosis might be scuppered by unanticipated future events (the patient might be run over by a bus)... -
nhthinker at 21:08 PM on 3 August 2010On Consensus
If a science has lots of models, which even the advocate is not confident in its predictive ability, then the science is clearly not reached a 4.5 to 5 level of confidence. If scientists start saluting a model that produces 90% long range results, then the science is reaching the 4.5 to 5 level. Broeker's analysis was directionally correct. I do not know anyone that is claiming CO2 has no impact: the primary issue is the accuracy of the level of impact. The advocates here seem to fall into the fortune teller's trap. There will always be some accurate prediction of of future events, especially when you have thousands of predictions to choose from. Much of the politics of the issue focus on taking extreme predictions out of context to intentionally scare people. The emphasis for a science to reach the stature of a 4.5 to 5 standard needs to be cold and calculating aspects of the math involved. From Gavin Schmidt's article on Hansen's predictions: But can we say that this proves the model is correct? Not quite. Look at the difference between Scenario B and C. Despite the large difference in forcings in the later years, the long term trend over that same period is similar. The implication is that over a short period, the weather noise can mask significant differences in the forced component. This version of the model had a climate sensitivity was around 4 deg C for a doubling of CO2. This is a little higher than what would be our best guess (~3 deg C) based on observations, but is within the standard range (2 to 4.5 deg C). Is this 20 year trend sufficient to determine whether the model sensitivity was too high? No. Given the noise level, a trend 75% as large, would still be within the error bars of the observation (i.e. 0.18+/-0.05), assuming the transient trend would scale linearly. Maybe with another 10 years of data, this distinction will be possible. However, a model with a very low sensitivity, say 1 deg C, would have fallen well below the observed trends. I'm curious if Gavin Schmidt thinks Climate science has reached the predictive ability of medical science. I kind of doubt it based on what he wrote in the article. Anyone here with enough connections to ask him? -
Stylo at 21:07 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
doug_bostrom, #77, From Doran:An invitation to participate in the survey was sent to 10,257 Earth scientists. ....With 3146 individuals completing the survey, the participant response rate for the survey was 30.7%.
Voluntary response; not a random sample. They also whittle it to 8.5% (climate scientists) + 5% (publish in climate science) of the 30.7% who responded. 12.5% times 30.7% is 3.8% of the original. It's not really surprising that those who have the most to gain from actively publishing in a field promote the scare hardest. -
JMurphy at 21:03 PM on 3 August 2010Grappling With Change: London and the River Thames
The "London Regional Flood Risk Appraisal" link doesn't work, because it contains the Skeptical Science address. It is showing this as the address : 'http://www.skepticalscience.com/%20http://legacy.london.gov.uk/mayor/strategies/sds/docs/regional-flood-risk09.pdf' -
CBDunkerson at 21:03 PM on 3 August 201010 key climate indicators all point to the same finding: global warming is unmistakable
stmwatkins #126 wrote: "My question was about differentiating the anthropogenic forcing from natural forcing, and that appears to be mainly through the GCM's." Again, the point I am trying to make is that this is NOT the case. There is just as much evidence of the degree of anthropogenic forcings (as opposed to natural forcings) from direct measurement and proxy records as there is from GCMs. Take a look at the very next post after this one... which gives ten indicators that the warming is human induced. Notice that the GCM models aren't included. When you can measure an increase in surface IR radiation at the bandwidths impeded by CO2 you DON'T have to rely on a computer model which predicts that you will see that increase... you are observing it directly. When you can find proxies showing that past incidents where the climate was similar to current and then the temperature went up five or six Celsius (over several centuries) as atmospheric CO2 concentration doubled you DON'T have to rely on a computer model which predicts that will happen as humans double CO2 concentrations now. GCMs are nice, but they are NOT the 'main' drivers behind climate science at all. Indeed, it is precisely the other way around... the values we get from direct and proxy measurements of climate forcings are FED INTO the climate models. On the Arctic sea ice fantasy league, hey we have to get our climate fun where we can find it. Yes, 'extent' is a highly weather dependent factor and thus virtually impossible to predict accurately on an annual scale... but that's why its fun. As to a random yearly fluctuation not being a 'scientific victory'... entirely true, and something we've been trying to explain to many self-styled 'skeptics' for a LONG time. In 'skeptic' land any year which does not set a new record high/low indicates reversal of the trend. Thus, for the past two years the sleight increase in Arctic extent indicates a 'recovery'... despite the volume of ice continuing to decline. I for one thus look forward to 'new record' years so I don't have to listen to the butchery of statistics about the 'trend having reversed' for a while. -
adelady at 20:36 PM on 3 August 2010Why I care about climate change
HR The poor should look after themselves? Well it would have been a whole heap easier for remote villages in African or South American forests or the mountain fastnesses of Pakistan if the technology had been routinely available for small scale power generation. I don't believe it's automatically the evil capitalists who deprived them. It's a combination of 19th century govt ideas about big and / or centralised being better and the aforementioned ECs lining up to make money out of that model. Now we have to make up for our own foolish shortsightedness. How many fewer wars might we have had in these last 30+ years if impoverished, ignorant people had been getting an education and making money with their own small businesses in peace and relative plenty. We can do the right thing now. Hopefully it won't be too little too late. -
christianhunt at 20:28 PM on 3 August 2010Why I care about climate change
John, For me, your site demonstrates the internet at its absolute best. Many thanks for your efforts. Christian -
gpwayne at 20:10 PM on 3 August 2010Why I care about climate change
The Ville:The difficult thing is and will be to say to people that they need to do without. I don't think any socialist or capitalist has the guts to say that.
Interesting you should put it that way round - where ideologues are telling others 'they need to do without'. It is the heart of the problem as I see it - the perception that people are telling others what to do - and their motives are either noble and rational (science) or ignoble and manipulative. While we require others to remind us that money cannot buy happiness, despite the eternal quest to prove this adage wrong. We cannot evolve society while so many of us think our very value, our worth, our achievements and our legacies are all measured by what we own, what we throw away and what we bequeath after we are gone. We need reminding how unhappy we are when we measure ourselves using such a poor metric as consumerism,the current religion of the masses. While this is true and we subsist on the treadmill forever wanting more, we have to be 'told' what's good for us. It is about time we figured this out for ourselves. -
HumanityRules at 20:10 PM on 3 August 2010Why I care about climate change
32.adelady My form of social justice does not lead me to think we should look after the poor and weak but that they should be empowered to look after themselves. I don't feel sympathy for them but empathy toward them. I think at the very least we should be supporting the likes of India and China to industrialise their societies. Taking John's example of the flood effects on Pakistan, it has always slapped me firmly in the face that flooding (or other natural distasters) in developing countries lead to huge losses of life while in the industrial West this is generally not the case. This is not because of climate change but due to the lack of resourses and wealth. This lack of wealth is not because of climate change but because the free market demands these conditions to exist. The recent focus on climate change as the greatest problem facing the worlds poor ignores the real problems underlying the society we live in. (Just to be clear my anti-religion stance comes from being raised a catholic and having little time for the hypocracy of organised religion. I'm happy to tolerate the full range of human beliefs although I do think we can all show a little love to our neighbour without the need to resort to a god figure) 31.Stephen Baines. I can't look at climate science without knowing there are political agendas at work as well. Only today this innocuous paper got me boiling because I see intention in the way the results are interpreted. I can't say what motivates the authors of this paper to draw the conclusions they do but I can't help thinking they are flawed. It should be a simple case of science showing one thing or another but it isn't. -
Dikran Marsupial at 19:54 PM on 3 August 2010On Consensus
nhthinker As I have explained "90% accuracy" is pretty much a meaningless phrase in terms of climate prediction as accuracy can only be assessed relative to the internal variability of the climate as this is the cause of an irreducible uncertainty in any prediction (i.e. it doesn't go away even if the model is perfect). You asked for a model that had proven accurate, and I gave you Broeker's as an example. Dismissing his quantitative prediction of 20th century warming (even though it was accurate) because Broeker wasn't confident is merely moving the goalposts. How about Hansen's 1988 predictions, which get the post 1988 trend broadly correct (scenario B was closest to the observed emissions etc)?
"A good model would define a function that twenty years into the future that would contain all the variables needed to make the prediction. Solar variability, CO2 and other GHG, volcanic activity, etc"
The models used for climate prediction already do include all of those things.
"Then, the twenty years of data is plugged in to see if the model from 20 years in the past can produce a prediction that is 90% accurate. "
That sort of thing is already routinely done (see e.g. here), except that as I have pointed out the "90%" accuracy bit is a meaningless criterion (you have to look at the error bars of the prediction, some of that is an irreducible uncertainty that would affect any prediction, no matter how good the model).
IIRC the IPCC report has a chapter on model evaluation (I'll check when I am next in the office). Perhaps if you comment on the failings of the assessment activities described there we could have a more concrete discussion?
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Doug Bostrom at 19:45 PM on 3 August 2010Why I care about climate change
The Ville: The difficult thing is and will be to say to people that they need to do without. I don't think any socialist or capitalist has the guts to say that. Perhaps I'm just weird (perhaps?) but the older I become the less I seem to want. I still have way more extra stuff than probably 90% of the people on the planet (comes automatically where I live) and I assume my failing inclination for acquiring material things has sharply defined limits. Do any other perhaps slightly 50+ people with creeping arthritis, ~12" optical depth of field, etc. have the same perception? -
Deech56 at 19:36 PM on 3 August 2010Why I care about climate change
As a fellow Christian, I would just say that it's not religion that may drive us, but teachings like "Love your neighbor as yourself." John's point fits in well with the followup question, "Who is my neighbor?" For non-Christians, we are not monolithic. Mainstream churches accept science as the way to learn about the physical world and take our role as mere stewards seriously. Many allies, same goal - to make sure there's something left for the next generation, and not mess up what is not ours. -
macoles at 19:35 PM on 3 August 2010Why I care about climate change
I agree with andrewcodd @43 Except I wouldn't single out "Extreme Atheism", any extreme belief system is bad news for society. Atheists are no more likely to be extremists than others. Atheists are no more likely to be amoral either. Doug Bostram mentioned the "Golden Rule" earlier (go look it up in wiki if you're unfamiliar). The Golden Rule is the basis of all social morality that binds everyone together, and no religion can claim it as their own -
Doug Bostrom at 19:12 PM on 3 August 2010Grappling With Change: London and the River Thames
Hi, HR. I did run across that, and thank you. The pace of formulation and publication of planning documents is pretty swift. Those issues also did not escape the notice of the folks managing floods; subsequent to the analysis from the CSPP language in some of the governmental planning documents was amended to reflect the changing nature of closure events. If you follow the link at the bottom of the graph you'll see what appears to be the latest deconvolution of the reasons for closure, leaving tides as an increasing factor; the graph seems an accurate summary. Helps to note that CSPP's writeup is missing the latest 6 years of data. -
andrewcodd at 19:10 PM on 3 August 2010Why I care about climate change
The fundamentalist comments seem to be from aetheists. We should all be greatful for whatever motivates individuals to become better people be that books like the bible, children or peyote. Extreme aetheism seems to lend itself to hedonism and irresponsable consumption. Not to say aetheists go knocking other people hats off for fun but social darwinism means that we look after our own above all. Beleif systems are tools we have evolved to help us extend the network of who we consider our own. I am agnostic and whatever I choose to beleive has no bearing on how it is I have come to be conscious. No aetheist or religion I have ever encountered can explain consiousness. Deep down its selfless individuals like John that keep me topped up with inspiration to do the right thing on a daily basis. Most sincerly I wish you all the best John. -
adelady at 18:59 PM on 3 August 2010Why I care about climate change
The Ville. "some people are going to have to suffer"? People are already suffering. Needlessly, which is the thing that breaks my heart. I do not see exactly what people in OECD countries will have to do without. Many people don't like change, but that's too bad because there is always change. Getting power from a solar/tidal/geo/wind source is still getting power. Better public transport run by that same power source is still better public transport. More efficient cars and trucks are better cars and trucks. My great regret is that the distortion of development of power technologies means that the poverty stricken regions of the world didn't have access 30 years ago to local power generated by wind or solar. It wouldn't have been wonderful by our standards, but it would have made an enormous difference to people who still have nothing. -
Paul D at 18:57 PM on 3 August 2010Grappling With Change: London and the River Thames
It will take me some time for me to read all your post Doug. London is the iconic city in the UK that will be troubled by sea levels in the future, but it won't be the only place. There are many UK cities that will be struggling. Portsmouth for instance is on an island and will probably be impossible to defend, whilst Southampton is on an estuary and could be defended, at least to some extent like London. How many billions will it cost? -
HumanityRules at 18:53 PM on 3 August 2010Grappling With Change: London and the River Thames
I realise this is a right wing think tank but they raise a good point, it was the first thing I thought when you graphed the historical record for the London Thames Barrier. What if the rules have changed for closing the barrier? It appears they may have. CSSP It looks like they lifted the second quote (and much of the info) from here. -
adelady at 18:46 PM on 3 August 2010On Consensus
Erik, you beat me to it. " A good model would define a function that twenty years into the future that would contain all the variables needed to make the prediction." Why do we need models this good anyway? Governments constantly make decisions and major investments on models from economists, transport analysts and dozens of others. How often do any of them produce anything as good as Hansen? -
Paul D at 18:44 PM on 3 August 2010Why I care about climate change
Ha, I was reading through all the comments here with optimism then came to number 39 and Argus, who seems on the surface to be confused. My interest in science is due to the fact that I want to know how things work. I guess it is an engineers view but it is also one that is fascinating and empowers the mind. I think the fact that climate science is linked to quantum physics and other sciences makes it compelling. You only have to spend some time contemplating the nature of matter and the forces that bind it and then quickly look at the objects around, to see the beauty of science and the world around. Out of the strange alleged chaos of the atom and particles, comes the greenhouse effect, cars and computers. But for me it isn't strange or chaotic, it does make sense. On the issue of this left/right thing. I think most politics of the old variety focuses to much on satisfying human needs and that conflicts with the observation that humans are causing the problems we have, be it climate change specifically or other environmental problems. The difficult thing is and will be to say to people that they need to do without. I don't think any socialist or capitalist has the guts to say that. So although I think 'social justice' is noble and it helps today's populations I think ultimately socialists are going to have to accept that to solve the problems, some people are going to have to suffer. I think it is to late now to protect jobs or wealth because of 'rights'. -
Doug Bostrom at 18:33 PM on 3 August 2010Why I care about climate change
God is love, love to spare, love enough to care for others. Is that sufficiently vague as to be nonthreatening to everybody? I took a moment to look at the scriptural citations John mentioned. I don't think it takes a genius to get the point. -
Argus at 18:09 PM on 3 August 2010Why I care about climate change
If there is a Christian God, who is both benevolent and omnipotent, we should stop worrying about the climate altogether. He can certainly fix the climate if we mess it up a little, and if he really is good, he will do so before anything serious happens. Thus we can continue to live on earth in peace and happiness, burning oil and coal that was given to us to burn. -
Erik J Smith at 18:07 PM on 3 August 2010On Consensus
nhthinker, How about this one: http://www.realclimate.org/index.php/archives/2007/05/hansens-1988-projections/ "The bottom line? Scenario B is pretty close and certainly well within the error estimates of the real world changes. And if you factor in the 5 to 10% overestimate of the forcings in a simple way, Scenario B would be right in the middle of the observed trends. It is certainly close enough to provide confidence that the model is capable of matching the global mean temperature rise!" -
JMurphy at 17:39 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
Poptech asserted : "JMurphy, I have no idea why you keep repeating the same lie about authors protesting the list, as no author has protested the list." It's a shame that these have to be produced yet again : A quick count shows that they have 21 papers on the list by me and/or my father. Assuming that these are Hypothesis 1 type bloggers they'd better change that to 429 papers, as their list doesn't represent what they think it does. Roger Pielke Jr There is nothing in my writing that fits in this category. If they sopport _your_ skepticism then I suggest retitling the post to be: "450 Peer-Reviewed Papers Supporting My Skepticism of "Man-Made" Global Warming" Roger Pielke Jr Re: The 450 papers list I just noticed I’m the lead author on one of the papers on the list. I have absolutely no idea how that paper could be construed as “skeptical of man-made global warming.” I have no idea how it could be construed as saying anything at all about man-made global warming. Harold Brooks But we all know the drill now : Poptech knows better than the original authors. Round and round and round...ad nauseum. -
macoles at 16:55 PM on 3 August 2010Why I care about climate change
Belief affords us all manner of ideology and it allows us to act as we see fit without having to scrutinise every last detail ourselves. Of course it has value to society! How many people would be advocates of AGW if it was a prerequisite to learn all that there is about climate science? Thankfully belief has its place alongside science, without it many would not act at all. Belief is a placeholder for both what science cannot explain, and for what science can explain - but is difficult to understand. Others will argue that belief offers even more, but that is OT... -
gpwayne at 16:28 PM on 3 August 2010Why I care about climate change
Hi John, I was surprised by your remarks about faith, but I do find your views reflect the best of Christianity and what I've always thought it was about - right thoughts, right actions, care for others - differentiated responsibility, as I would name it. The hard question - that others have tacitly raised - is how one fits a religious (belief) based world view with a scientific one, and I wrote an essay about this a while back. My main thought was that we need mystery as well as the hard bright light of science:"At the heart of belief lies mystery; that which our consciousness requires faith to address because all other methods are inadequate. Science would, if it could, eliminate all mystery from our existence, because to do so would not only be the attainment of science's ultimate goal – the theory of everything – but also invalidate belief and faith as tools (which science despises), in favour of hypotheses and rigorous proofs (which science adores). A mystery, tacitly left unsolved, is not seen as an asset to the human condition, but a weakness of mind, a vacuity of intellect or a failure of method. The unknown has no intrinsic value to science; it is merely that for which the appropriate mathematics has not yet been formulated. It is therefore all the more interesting to me that the place where science gets in trouble is the very same junction of the known and unknown that humans find so provocative, and from which we are rewarded so generously – and mysteriously – from time to time...I speak of the small epiphanies, the wonder of it all."
A Mysterious Reduction Small epiphanies - the title of the book in which this essay appeared, and also of my blog, where the essays can be downloaded (free). The balance between the mystery of being aware and the sensible deployment of the rational tools that awareness affords us is one of the most interesting and challenging subjects I write about. -
Ferran P. Vilar at 16:22 PM on 3 August 2010Why I care about climate change
Dear John, As you know, I blog in Spanish exactly for the same reasons. Well, just a (little?) difference. I’m an agnostic, but I’m proud to hold deep ethical values and I’m happy to know that I’m embracing Matthew 25 as you and many readers of your blog are. I discovered the seriousness of the climate change issue almost by chance in 2005. It was in the USA, when I was there in ‘technical’ vacation with my daughter, then 12 years old. I could not conceive to keep my job and do nothing for the world I was leaving to her. Then I saw the deep injustice for the poor people of the world to be directly harnessed by our daily ‘normal’ actions. I was frustrated to see people acting the same way as if nothing was happening, and being really influenced by the denial machine. I felt the instinct to investigate and make it public in Spanish language, where nobody was doing anything at the time. Somebody helped me: I was fired from my job (publisher of an automatic control business magazine) when I wrote an editorial on global warming and the responsibility of the engineering community to deal with. And finally, being trained in system dynamics (I’m an electronic engineer), I understood what the destabilization of the climate system could mean: runaway, a different planet, much less comfortable. Lovelock foresees some 1 billion people leaving at the poles by 2100. How do you reduce 8 billion people in 100 years? I still wonder why the climate system is, with some exceptions, not studied from this point of view. It’s like an engineer analysing a structure by starting with the quantum mechanics equations of every particular material in a bridge. “That’s because climatologists are atmospheric physicists”, I’ve been told by a renowned British researcher. They don’t know control theory? What is the stability threshold of the climate system? Why anybody talks about it? Is it 2 degrees? No, I think it is too much. Do people understand what does it mean if we had already gone through? John, please be careful. I deeply resonate with your cartoon. I admire your productivity - mine was higher some months ago. Two couples left me because of what they consider an excessive involvement (with zero income), and “you’re not going to save the world”. None of them was the mother of my lovely daughter, but if yours is, remember that anything better for a child than to have both parents at home. But it would also be difficult to find anything better for all of us than your independent and clever blogging. -
muoncounter at 16:21 PM on 3 August 201010 Indicators of a Human Fingerprint on Climate Change
#41: "a doubling of CO2 would only cause 1.1-1.2C of warming," CO2 has been increasing at an average of approx 1.5 ppm/year for the last 50+ years. Keeping that constant you'd expect to double (say from 330ppm to 660ppm) in 220 years. Some people argue for locally higher rates of global temperature increase, but one figure you often see is 0.13C per decade. So 22 decades gets you 2.9C hotter. Unfortunately, the rate of CO2 increase is edging up towards 2ppm/yr. -
canbanjo at 16:16 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
Poptech you have already confirmed your list is not about quality. Its a numbers game. Very clever mind if what you seek is attention. -
apeescape at 16:09 PM on 3 August 2010Why I care about climate change
miekol, if the composition of the molecules in the atmosphere is proportional to the effects of global warming, that means all molecules behave similarly. When I put a dash of salt (unlike dried basil) on my steak, it tastes so much better even though it's only 0.003% of the mass. @ 0.005%, maybe a tad salty :) I grew up in an a-political, a-religious environment, raised under immigrants; so the only real "value" that were installed in me, were to work hard and be nice to others. I'm also young, so I feel that I may take the fruits of intense capitalism too lightly. At the same time, I've been exposed to its side effects from childhood (mental health, environment). "Happiness" is only a saturating function wrt wealth, and a sustainable lifestyle is truly appealing (1 steak / yr not withstanding). Global warming is a top-dog issue, and it's very hard not to get involved with it. -
Doug Bostrom at 16:00 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
GC, it never fails to astound me how gullible those folks are. Perhaps they should spend a little less time backslapping and a little more reading papers, such as Doran's for instance. "76 self-selected" zooming round the world nearly at Big C, or at least as fast as the packets can be crammed through fiber and routers. Tsk-tsk. -
gallopingcamel at 15:45 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
Great work! At last you got WUWT to acknowledge your existence: http://hockeyschtick.blogspot.com/2010/08/97-consensus-is-only-76-self-selected.html -
Doug Bostrom at 15:45 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
Stylo, are you speaking of Doran? Would you mind rephrasing your objections from a survey methodology perspective? You can find Doran's paper here (full text pdf). -
barry1487 at 15:41 PM on 3 August 2010Why I care about climate change
John Cook, thanks for the post. I have no religion, respect yours, and feel just the same way you do re social justice. Having no children, I sort of adopt everyone else's in my mind and I am concerned for what we leave the following generations. -
Stylo at 15:29 PM on 3 August 2010Visually depicting the disconnect between climate scientists, media and the public
robhon #21:...the response rate of the questionaire would have no bearing on the poll results. The sample size is large enough...
It's not the sample size, but whether it is random. It is not random. Once the participants can decide who is qualified to answer, and the authors can decide which views are in and which are out, it becomes an merely exercise in propaganda. Anyhow, you burst your own bubble when you said that art quality can be objectively agreed upon by consensus. Maybe in Communist countries where a board of culture decides what's right; but not here in the West. -
James Wight at 15:26 PM on 3 August 2010Why I care about climate change
Interesting post. It prompts me to reflect on my own motivations. Like many other commenters, I’m an atheist, so it’s not religion that motivates me. And although I do have a political view on the issue, I wouldn’t exactly say that it’s what motivates me either. It’s more the other way round: I developed firmer political views from looking into the science. My main motivation is to counter denialism (or contrarianism, or whatever you want to call it). I’m against denialist movements of all stripes, and am incensed when I see anti-science and pseudoscience wielding so much influence in the world, especially on an issue as important as global warming. I think it is vital that the public, media, and politicians understand the issue so that policies can be based on evidence, not ideology. Also, I can’t help pointing out the obvious link between creationism (particularly young Earth creationism) and climate change denial. If you already believe that the scientific community can be so wrong, yet so certain, on one issue, it’s not too much of a stretch to extend that to others. And if you believe the Earth is only a few thousand years old, then you’ve already discarded most of the paleoclimate record in one swoop! On a more optimistic note, I have to agree with Stephen Baines @30: “If this thread has done anything I think it highlights how people from a wide range of backgrounds can reach roughly the same conclusion simply through an honest effort at following the evidence.” This is how it should be. Science relies on empirical evidence and so should transcend ideological boundaries. Unfortunately that doesn’t always happen in the public sphere, but this site demonstrates that it can. I think this is largely thanks to John’s politically neutral, fact-based approach. -
chuckbot at 15:21 PM on 3 August 2010Has Global Warming Stopped?
Great post! My only question is about the technical details of assessing a confidence level for the presence of a warming trend- how is it done? I've googled a bit but everything I've found is a bit opaque. I imagine it goes something like this: a set of data {(x1, y1), (x2, y2), ... (xn, yn)} has a linear regression y = m*x + b. the 'range of the data' is Dx = xn - x1. the 'spread of the model' is calculated Dy = m*Dx. Dy represents the amount of change in the regression over the sample range. Dy is compared to the standard deviation of the data, std(y1, y2... yn), to gauge the confidence level of the observed trend (for example, 2 standard deviations = 95% confidence). Am I on the right track? -
adelady at 15:19 PM on 3 August 2010Why I care about climate change
@HR "humanist, left-wing with a strong sense of social justice" Amazing. Almost a match for me, but I'm atheist rather than anti-religious. I half get it when I see union officials with an obvious commitment to social justice - for their members - arguing for certain industries or practices to continue despite being socially destructive. But a general commitment to social justice takes me to John's view. That we have to look out for the poor, weak and vulnerable, whether we're likely ever to know them or not. As Stephen said, presuming you can predict another's position on the science by labels like left, right, religious or anything else is futile. I suppose anyone can have a general distrust of academia regardless of political orientation. But this one perplexes me. -
frankride at 15:09 PM on 3 August 2010Has Global Warming Stopped?
Get educated. Educate yourself about global warming. The more facts that you have as to what mainstream science says about it, the more you can persuade others to make simple yet effective changes in daily behavior. Energy-saving techniques either are initially expensive (for example, solar power) or take extra time (for example, recycling), so many people need to be convinced that their efforts matter.[9] Always keep in mind that you are aiming to demonstrate the benefits of these activities and highlight how each person can play a vital role in helping to reduce global warming. Remember that "[c]ivil society does not respond at all well to moralistic scolding."[10] Use education to enlighten, not frighten. 2Vote and influence your government with telephone calls, e-mails, letters and meetings with those who represent you in government. Learn as much as possible about the policies that you advocate before doing so; solving one problem often creates others. For example, replacing incandescent light bulbs with compact fluorescent light (CFL) bulbs has increased the hazard of mercury contamination in homes and landfills. Fluorescent light bulbs are still preferable to incandescent bulbs (see below), but one must be careful to recycle them and to not break them, releasing the mercury. The push to grow corn for ethanol has contributed to higher food prices while saving little energy, if any at all. http://www.globalwarmingsurvivalcenter.com/ -
Stephen Baines at 14:59 PM on 3 August 2010Why I care about climate change
@ HR...You make my point perfectly! Simple stereotypes need not apply! One question...You refer to the politics of climate change. What about the science of climate change? Does your background affect your opinion about that? -
apeescape at 14:57 PM on 3 August 2010Has Global Warming Stopped?
Dikran @ 16, I think you meant 1 - beta is the power? I get about 80% power for 12~14 data points when 2009 is the latest year for GISS (albeit w/ a few caveats). fydijkstra @ 20, an n-1 polynomial can fit a dataset of n points, so R^2 is really not a valid measure of comparison in any situation. The adjusted-R^2 may be a little better. Also, your degrees of freedom goes down with increased predictors, which decrease power. IOW, if you pick a different range of dates (even w/ same sample size) to do the same analysis, your results won't be as robust. Babyak. (2004) What You See May Not Be What You Get: A Brief, Nontechnical Introduction to Overfitting in Regression-Type Models In general, I think it's very hard to extrapolate / predict a future without including at least some physical structure to the models. I've noticed most people who predict a near-future cooling go by purely statistical arguments or really broad-brush physical observations. The people who do predict significant warming are the attribution guys.
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