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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 80301 to 80350:

  1. Trouble Brewing in the North
    At the moment, this post says "Posted on 14 July 2011 by MarkR". Does this mean we have the time machine Tom Toles suggested as the fix for global warming? :-)
  2. 2010 - 2011: Earth's most extreme weather since 1816?
    Dikran Marsupial @ 236 I will attempt to answer: "Norman, take a GCM, which embodies our knowledge of climate physics. Apply CO2 radiative forcing, and observe an increase in rainfall frequency and intensity. Does it then become science?" Here is the Wikipedia definition of science which is similar to other definitions. Science Definition. "Science (from Latin: scientia meaning "knowledge") is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the world." The testable explanations would be the mechanisms I have been asking for. The mechanisms that drive extreme thunderstorms are well established and predicatable. Meteorologists can look at initial conditions and predict with high degree of confidence the severity of thunderstorms that will develop. Now for your question. It would be a science if the models have known mechanisms for explaining why the preciptiation will increase (such as, increased evaporation caused by a warming earth due to CO2 forcing) and then if they had predictablitly. If the model forcasts a given increase in frequency and intensity of rainfall over an area during a specified period of time, and the actual rainfall in the area comes close to the model's prediction over a given number of areas (one correct prediction would not be enough to qualify the model as science) then I would say the model is now a science. It has achieved the goal of predictability that is necessary for it to be considered a science. In the example you provided it goes back to what one considers extreme. In your example 40 mm a day is considered extreme. "Extreme rainfall is chosen as precipitation greater than 40 mm/day chosen on the basis of prior research indicating that rainfall at this intensity has the potential of causing soil erosion and flooding." I don't think any farmer in my area would consider a 1.57" rainfall in a day an extreme amount. I would doubt such a rain would lead to flooding unless the soil was highly saturated and it all fell in a really short time.
  3. German Energy Priorities
    peter prewett And the residence time of CO2 in the atmosphere is...? It boils down to the lesser of two evils, every time.
  4. The Planetary Greenhouse Engine Revisited
    Re Michele Well then. Where is it the physics inconsistency? Radiation doesn't behave just like water flowing under gravity, but borrowing your analogy anyway, what you've forgotten is that evaporation doesn't only occur in the valley, it occurs on the hill as well. In fact there is more evaporation, per unit area, on the hill than in the valley (the analogy gets tricky here as to why, but we could say it is because the wind is stronger on the hill. Actually it is by said evaporation that the water reaches the valley as well as space, and here the analogy falls apart almost completely. So please consider radiation physics.)
  5. Dikran Marsupial at 05:41 AM on 5 July 2011
    2010 - 2011: Earth's most extreme weather since 1816?
    Norman@235 In post 231, I asked you a specific question, that you ought to be capable of answering directly. Sadly all to often discussions of climate science with skeptics end up with the skeptic unwilling to state his position clearly and unambiguously. I have learned that that is usually the indicator that no further progress will be made and it is a waste of time to continue. That modelling extreme events involves uncertainties does not mean it isn't science.
  6. A Detailed Look at Renewable Baseload Energy
    Mark Harrigan Thanks for your thoughtful response. First, I obviously agree with you on the (to some) surprisingly 'safe' nature of nuclear (see #101 for another way of looking at this: sum total plant operating history over last 40 years = 11,255 years; 18 INES rated incidents over this period, only Three Mile Island, Chernobyl and Fukushima 1 rated above INES 4). But the risk/hazard question is real, although it pays to remember that Generation III plant is inherently far safer than Generation II. Also, those who fret most about terrorist threats to reactors and waste transport know least about reactor containment vessels and Type B transport package specs. The best way to keep operators on their toes is continuous, unscheduled, independent inspection with absolute power to require access and disclosure. Nothing less will do. And yes, I can see it being a big problem with the Russians and the Chinese and other contrarians, but that's a political fight worth having and frankly I'd be very happy with somewhat ill-tempered Chinese and Russian teams picking over US and EU plant really looking for something wrong. We would of course be doing the same for them. Even so, this is where it gets hard. If you ask around on this site about the risk/hazard analysis of AGW, you will get a variety of answers, mostly high/high or worse. That's the policy bullet to bite. What infuriates me is that only Hansen and Lovelock actually criticise the massed ranks of anti-nuclear activists among the climate concerned for getting in the way of a difficult but necessary decision to expand nuclear. Anti-nuclear sentiment is Janus-faced; its other aspect is ill-founded renewables advocacy. The policy 'missing link' is the frankly naive claim that western democracies will somehow turn to austerity and energy poverty and deindustrialise to make it all work. It's wishful thinking on a par with AGW scepticsim - and similarly dangerous. Mike Hulme was correct to classify AGW as a 'wicked problem'. This sort of thing is exactly what he was talking about.
  7. 2010 - 2011: Earth's most extreme weather since 1816?
    Dikran Marsupial @ 231 Here ia quote from a very long report on climate models. The report is very long and detailed so I have not had to time to read through all of it. It seems climate models are fairly good at reproducing some climate effects based upon the actual events and they do continue to improve and evolve as more knowledge is gained and added. "Modeling of extreme events poses special challenges since they are, by definition, rare. Although the intensity and frequency of extreme events are modulated by ocean and land surface state and by trends in the mean climate state, internal atmospheric variability plays a very large role, and the most extreme events arise from chance confluence of unlikely conditions. The very rarity of extreme events makes statistical evaluation of model performance less robust than for mean climate. For example, in evaluating a model’s ability to simulate heat waves as intense as that in 1995, only a few episodes in the entire 20th Century approach or exceed that intensity (Kunkel et al. 1996). For such rare events, estimates of the real risk are highly uncertain, varying from once every 30 years to once every 100 years or more. Thus, a model that simulates these occurrences at a frequency of once every 30 years may be performing adequately, but its performance cannot be distinguished from that of the model that simulates a frequency of once every 100 years." Quote from this report: Climate models report.
  8. Eric the Red at 04:29 AM on 5 July 2011
    Great Barrier Reef Part 1: Current Conditions and Human Impacts
    jmsully, I was about to link to that article when I read your post. The bleaching appeared to be a short-term occurrance, similar to that observed in the Caribbean and elseware.
  9. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 219 I did as you suggested. I sent a query to Munich Re about what criteria they use to determine a dissater in their charts. I will have to wait and see if they answer it.
  10. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 232 I was reading up on the formation of preciptitaion events and what determines their severity. The thunderstrom you describe is known as an air-mass thunderstorm. Generally they are the least severe and the rain will cool the updraft and destroy the cycle. Even these need the one common factor in thunderstorms. You need a layer of unstable air (one where if you move a parcel of ground air to a higher level it will end up being warmer than the surrounding air and so continue to rise). I looked at some weather links to determine what causes the most severe thunderstorms. Moisture in the air is the definate fuel for storms but there are many factors that go into determining the intensity of a thunderstorm. I do not know if the 4% increase in moisture content of the air will make much difference (will continue to research this). Here are some links. Atmopheric stability and storm formation. Factors that determine the intensity of a thunderstorm. Stability of the atmosphere is one of the major factors in determining the severity of a thunderstorm. The less stable the more likely an intense storm will develop. Also upper wind variation is really important or the storm will choke itself off. The upper wind moves the region of downdraft away from the updraft allowing the storm to continue and intensify. Other factors are how fast the overall storm is moving. A strong strom that moves rapidly will not be a likely to produce flooding as a similar strong storm that moves much slower over an area. Will global warming create more regions of unstable air? Will these regions of unstable air be more unstable because of global warming? Will wind shear become stronger as the earth warms? If these questions can be determined to be a yes then I would agree with the hypothesis that global warming will increase the number of severe storms, more rain, hail, wind and tornadoes all with the potential to increase damage to target areas. In the US the term used is severe weather. An extreme weather event would be one significantly worse than normal severe storm events.
  11. It's the sun
    Well, I didn't understand the figure. Of course, because the IPCC didn't adopt it the right way from the original (Stott et al (2006b)). In the original work it is as I told that it has to be: while the global dimming the only natural caused temperature is higher than the total (anthro+nat). So what did the IPCC do, or at least the authors that wrote the chapter?! (Possibly this may be the reason why the link to the corresponding appendix is now broken in the IPCC documents. Who knows...) Ok, I'm again off topic. Back to it. The first paper you've linked is a good chance to get enhanced knowledge about another part of Sun's influence. But, if you are aware of it, this is in addition to the solar components that were used so far (TSI and SSN) and it is surely not the only parameter that may be of importance. Perhaps it will come up to the IPCC documents in the future (I hope so). As to Hansen, I will have a closer look at it. But obviously he didn't know about the global dimming because in Fig.1 (base of the whole work) the net forcing is steadily rising (except the volcanoes) what definitely would have disabled a cooling that was observed. I'll come back to it (in the right topic, of course).
  12. Mark Harrigan at 02:05 AM on 5 July 2011
    A Detailed Look at Renewable Baseload Energy
    @BDD on the nuclear issue You say "We need to get past the all-consuming anti-nuclear bias and accept the unpalatable facts as they stand. Then formulate energy policy that makes sense." I agree that too often the nuclear question gets submerged by emotionalism. The question is what unpalatable facts do we need to consider? Despite the problems associated with the issues in Japan the fact is Nuclear has a far better safety record per MWh generated than any fossil fuel by orders of magnitude. The deaths per TWh for various energy sources are here Deaths per TWh Energy Source Death Rate (deaths per TWh) Coal – world average 161 (26% of world energy, 50% of electricity) Coal – China 278 Coal – USA 15 Oil 36 (36% of world energy) Natural Gas 4 (21% of world energy) Biofuel/Biomass 12 Peat 12 Solar (rooftop) 0.44 (less than 0.1% of world energy) Wind 0.15 (less than 1% of world energy) Hydro 0.10 (europe death rate, 2.2% of world energy) Hydro - world including Banqiao) 1.4 (about 2500 TWh/yr and 171,000 Banqiao dead) Nuclear 0.04 (5.9% of world energy) I'm not sure about the veracity of the energy splits but taking this data at face value then Nuclear appears to be very safe. BUT (and it's a big but) I think to consider the nuclear issue we must first examine safety in its two component parts. Risk (chances of something going wrong) and Hazard (impact of something going wrong). With nuclear technology (even older technology such as at Fukushima) the risk is actually vanishingly small - but the hazard is enormous. The question is can we manage the hazard? So far Fukushima suggests this is a major problem. IF something goes catastrophically wrong (which clearly can happen) we simply cannot cope. So the issue of hazard is huge. Perhaps this is acceptable though if the risk is so tiny? After all we accept airline travel as commonplace and it is somewhat analogous (the risk of an accident is about 1/60th of car travel) although it can be argued the hazard is high (plane crash = almost certain death whereas it is not certain with a car accident) Until recently that was my view and I was a passionate advocate for Nuclear as the "obvious" solution to AGW. The technology is CO2 free in operation (yes I've heard the tired arguments about life cycle but they've been comprehensively refuted). It works and is proven as a reliable 24/7 base load/peak demand supply (as opposed to almost all renewable alternatives which - whilst promising are not yet proven). It's relatively cost effective and whilst waste management issues are real they are not beyond solution or management (as existing countries with an extensive nuclear history show). And the risk of something going wrong is tiny - even better if you site it somewhere geologically appropriate. So far so good for the technology - especially when you consider that new designs are way better. But the problem is the risk is not just in the technology. What makes it worse is where the human factor comes in. I think what Fukushima amply demonstrates is not so much that the problem with Nuclear is in the technology but in how it is managed. The management has been exposed to be one of avoidance of responsibility and cover up of what had really happened. This clearly increased the risk (made it more likely for things to go wrong) and has unquestionably exacerbated the hazard. I think most people sense this intuitively and hence that is why the "fear" of nuclear is so high. The hazard is enormous, sometimes unmanageable and there is simply not sufficient trust in fallible human management (which wants to avoid accountability) especially when it is profit motivated. So where do we weigh that up? I don't profess to know the answer I'd still like to think that we shouldn't be taking the nuclear option off the table. If we could improve our human management I think it has a role to play. But I can very much understand and empathise with why people are so distrustful of it as a viable alternative. It's hard to have an honest dispassionate debate about it because of the emotional factor but I hope some of this post helps. BTW in the interests of disclosure I am Atomic Physicist by training (not the same as nuclear but I have some knowledge)
  13. Mark Harrigan at 01:09 AM on 5 July 2011
    A Detailed Look at Renewable Baseload Energy
    Ouch! Looks like I've stepped into the middle of a nuclear debate! I'll come back to that @BDD #123 & #127 I think Mark D's contribution is a positive one EVEN if he is wrong - because it is focussed on what we need to do. You might want to consider the issue of right and wrong here On Being Wrong watch the video - it's enlightening and humbling Re the issue of gas fired turbines - you make an excellent point about just how fast they can spin up. But this seems to me a problem that some good thinking might overcome rather than a fundamental unsolveable problem We should invite some expert comment on this? My limited understanding is that gas turbines have a longer start-up time than conventional engines but no worse than coal or other existing "base load" technologies - all of which have to be "on" to provide power. I also gather gas generation is relatively slow to respond to changes in power demand - but that is all relative I'm told this is improved somewhat by Simplified Combined Cycle because of the pre-mixing steam and fuel before injection into the combustor. This enables a faster start possible because steam can be injected in the gas turbine as quickly as it is produced, avoiding steam turbine warm-up requirements.. The critical question is - how rapidly can this be done versus what is needed. I really don't know on what time scale this sort of demand management matching is required but I think it sounds like a technical challenge rather than a fundamental one. For example - momentum alone would ensure that the power from a wind turbine wouldn't suddenly drop to zero. What's more (and I don't know if this is done) surely a little bit of intelligently designed anemometry could be used as a short term predictor and signal to the grid that the wind turbine/farm was about to drop the load and spin up a gas turbine ahead of time. Perhaps there is someone who reads this site who could advise on the time scales required? Can we advance the debate by seeking solutions to the problems of renewables?
  14. Monthly Climate Summary: May 2011
    Michael, Thanks for this-- well, I think....pretty depressing actually. And "skeptics" actually believe that we "warmists" find cheer in these findings? No.
  15. Trouble Brewing in the North
    A wall of ice of that weight would be 300 feet tall and 300 feet wide. This is less than the 1/3 volume of the iceberg that came off of Petermann Glacier last year, they could have just chopped this up. It is one seventh the volume lost from Jakobshavn each year.
  16. Arkadiusz Semczyszak at 23:53 PM on 4 July 2011
    Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Perhaps[ -snip -]
    Moderator Response: (Rob P) Re-posting dubious links that have previously been debunked is considered trolling. Please desist.
  17. Trouble Brewing in the North
    New article this week: http://www.sciencedirect.com/science/article/pii/S092181811100097X "There has been a rapid acceleration in ice-cap melt rates over the last few decades across the entire Canadian Arctic. Present melt rates exceed the past rates for many millennia. New shallow cores at old sites bring their melt series up-to-date. The melt-percentage series from the Devon Island and Agassiz (Ellesmere Island) ice caps are well correlated with the Devon net mass balance and show a large increase in melt since the middle 1990s. Arctic ice core melt series (latitude range of 67 to 81 N) show the last quarter century has seen the highest melt in two millennia and The Holocene-long Agassiz melt record shows the last 25 years has the highest melt in 4200 years. The Agassiz melt rates since the middle 1990s resemble those of the early Holocene thermal maximum over 9000 years ago."
  18. John Brookes at 22:40 PM on 4 July 2011
    Glickstein and WUWT's Confusion about Reasoned Skepticism
    Nice post - thank you.
  19. Trouble Brewing in the North
    The Penny Ice Cap is one of the key ice caps on Baffin Island and its outlet glaciers are certainly in retreat in response to the mass loss, which generates thinning.
  20. peter prewett at 17:23 PM on 4 July 2011
    German Energy Priorities
    There is a posting on the BBC's web site on Nuclear: A tortuous timescale at:- http://www.bbc.co.uk/news/science-environment-13993997. There is a link on that page to the decommissioning of Oldbury Nuclear power station, the timeline is horrifying as the work will not be completed for another 100 years. That is if there is the manpower and oil to drive the equipment needed.
    Response:

    [DB] Fixed html in broken link.

  21. German Energy Priorities
    The future of energy is in renewables plus renewable nuclear. The current nuclear power plants use nuclear FISSION of either Uranium (specifically the U-235 isotope) or Thorium (actually Thorium-232 initially reacts with a neutron to form U-233, that unlike Th-232 is fissible): They are obtained as Uraninite-Thorianite ores (ThO2-UO2) or Cerium Monacite ores((Ce,La,Nd,Th)(PO4)) that must be mined and then processed. This means that there is high use of energy in the process of extraction and processing, and also huge amounts of waste are produced. The process for nuclear fuel is the following: Among the residues are the mill tailings, the depleted uranium (U-238) and most important, the highly radioactive (unlike the original U and Th) spent fuel.
  22. The Planetary Greenhouse Engine Revisited
    @ Patrick … (what physics could cause two radiating levels independent of composition and at odds with temperature) … For the radiative sweeping of the wasted energy, we have two spatial locations defined by the thermal orography of the planetary atmosphere. If we analyze the temperature profile we can view very well its likeness with an unique closed drainage basin (Venus) or with two closed basins (Earth), divided between each other by a watershed (stratopause) where the showered water converges to a single/double bottom valley lake which behaves as a sink and disposes of the collected water by evaporation (phase transition) and where the level of the water will be determined by the balance of the incoming/outgoing mass. Well then. Where is it the physics inconsistency?
  23. Lindzen Illusion #4: Climate Sensitivity
    "... still show climate sensitivity less than 1°C for doubled CO2." How much less, may I enquire? We've already had 0.8C for a 'mere' 40% increase in ppm CO2. By my reckoning, less than 1C must mean 0.97, 0.9, 0.85, 0.88, 0.85. Looks to be coming up pretty soon. Probably before 50% increase in concentration. Has anybody ever asked him directly how he could explain getting past 1C increased temp with 50% or less increase in CO2 concentration? (Even 60 or 70%.)
    Response:

    [DB] "Has anybody ever asked him directly how he could explain getting past 1C increased temp with 50% or less increase in CO2 concentration?"

    It's a kind of magic...

  24. Google It - Clean Energy is Good for the Economy
    Camburn "...one area close that has no dams on it right now. Yellowstone River. In my travels, I know the Missouri could have more dams." Why do we need power generation to always trash the environment it's taking total advantage of? Surely run-of-river would be a more sensible, multi-use option than dams sacrificing farmland, forest or wilderness. (Should point out I'm presuming that these rivers actually flow at a reasonable pace rather than wander leisurely across a flat landscape the way our River Murray does.)
  25. German Energy Priorities
    Err... that should be EROEI not EREOI.
  26. German Energy Priorities
    # JMurphy, If you look at the Sovacool piece and in particular Table 1 - Disadvantages of Nuclear Power, it reads more like a hand waving anti-nuclear polemic than anything else. For example:
    The energy intensity of the nuclear fuel cycle and energy pay back and declining reserves of high- quality uranium result in a low energy pay back ratio, whereby plants must operate for decades before they produce any net energy.
    Which sounds truly horrible, but is it in fact true? This piece suggests that EREOI has been steadily improving for nuclear power, not declining as Sovacool is implying. This should come as no surprise with the move from gas diffusion to centrifuge enrichment or the advent of new designs such as the Westinghouse AP1000 that are smaller and require a lot less steel, concrete etc. You can also take a stab at estimating the EREOI for nuclear by looking at the low whole life cycle emissions assessments, which are simply incompatible with poor EREOI assuming (very reasonably) input energy comes from fossil fuels. Table 1 is riddled with highly questionable assertions which very much look like fuel for debating points rather than anything else.
  27. German Energy Priorities
    Agreed, Dana. The world's politicians and lobbyists are using Germany as an example of how switching to renewable energy works and how effective it is (or is not). The better an example they set, the sooner places like Australia, Canada and U.S.A. might take real action.
  28. actually thoughtful at 12:19 PM on 4 July 2011
    Google It - Clean Energy is Good for the Economy
    Camburn in your post #32 you claim sensitivity is 1.0C - this is not within the currently accepted range and demonstrates you don't understand the physics. Will you kindly get of this thread (about the advantages of switching to clean energy NOW via a carbon tax) and get your confusion dealt with on the correct thread? It makes no sense for people to clog up EVERY single thread with the same tired, oft debunked claims. Frankly, Lindzen's claim that "what we've seen so far" suggests sensitivity is no higher than 1°C for doubled CO2 could not be further from the truth. Why don't you go to that thread, post all your credible facts and published papers that justify 1C - and if your ideas survive there, THEN bring them into general discussion, otherwise, you are just polluting the threads with debunked claims. You state some malarky about the status quo - YOU are the defender of BAU - which tanks the economy, and life as we know it. You are projecting to claim that that is somehow my position. It is a false claim. You would do better to not assume you understand (or question) my motives. Camburn if you only HAD an alternative view! All you do, on thread after thread, is post the same debunked claims about sea level, about 1C sensitivity - things we KNOW are false. PLEASE start presenting an alternative to BAU. As for your Chamber of Commerce level rah rah for North Dakota - Here is an article pointing out that EACH fracking well uses over one million gallons of water North Dakota Fracking Here we see North Dakota is not even in the top 10 for renewable energy production. Camburn do you have anything credible to add to the discussion?
  29. Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Pardon my ham fisted typing - that should have read AIMS.
  30. Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Rob - Spot on there! The AMS hardly starts from a pristine base.
  31. Google It - Clean Energy is Good for the Economy
    Actually thoughtful: I will point you to the differences in the IPCC WG1 report. My position is well within that range. The 3.0 is an AVERAGE of the ranges, and is no more credible than any number used within the report. I am not here to try and convince you that that magic 3.0C is the right number, as it is within the range of presented numbers. Each and every number "could" be correct. I have my reasons to understand a lower number, you have yours to understand a higher number. If you want to present a number that is not presented there, then we have the need for a mutual discussion. But, as I have observed from your comments on this forum, I feel there is no need. I understand the physics veryyyyy well as I have been studying this issue for over 30 years. Even a lemming cleans something in that period of time. You seem to be here to present the status quo as you understand it. I am here to present solutions that I know are viable and very doable, and without any uncertainty. I live in a state that has abundant, to say the least, fossil fuel energy. Yet, we are a leader in renewables as well. Doesn't that strike you, from your view, as being in a leadership position? We are a conservative state that watches the dollars, live the land, breath the air. The nature of placement provides us with extreme weather on an annual basis. It also provides us with weather cycles. Example is Devils Lake. If you don't think we understand this issue, I can only say you are sadly mistaken. We are also a state that is very well educated and at the forfront of practical research. Energy & Environment Research Our coal gasification plant has, and is, investing more in carbon capture. IF the rest of the world took as much interest, care, and preservation of the environment as ND does, there would not even be a need for this discussion. I do think you attitude towards someone who presents an alternative view needs a bit of refinement.
  32. Rob Painting at 11:38 AM on 4 July 2011
    Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Stevo/Chemware - I must admit I'm very biased against these sorts of survey results - they are contrary to what I've observed here in New Zealand too. Although we don't have coral reefs, I've witnessed a degradation in the local marine environment. Yet fisheries scientists assure the public that things are hunky dory and fish stocks are sustainably managed. It's preposterous - who do I believe them, or my lying eyes? It may be that fish stocks have been hammered down to a certain threshold and haven't plummeted any further -yet. That's a lot different to sustainably managed. I can dive in areas in there once existed vast schools of fish 20-25 years ago; now they're gone. Up and down the local coast we have proxy indicators for overfishing - kina (sea urchin) barrens. Crayfish and snapper feed on sea urchins, but in many areas vast armies are marching toward the shoreline stripping seaweed, which is a vital nursery for juvenile fish. It's a pretty good clue snapper and crayfish populations have been thrashed. I don't expect it helps at all to have such backward-thinking elements in ocean ecology research. Shouldn't we be making comparison to a healthy ocean state, rather than a grossly degraded one?
  33. It's the sun
    Perhaps you better have a look at this paper - note the authors = for latest on solar forcing before leaping to conclusion that solar is underrated. It also appears that you do not understand IPCC figure that KR posted. Noone expects (it would be utterly improbable) that temperatures follow the multimodel mean. You might want to look at this posting at RC for further explanation. Finally, a close study of Hansen et al 2011 might be useful. Especially note the comments on model handling of aerosol forcings in light of Argo data.
  34. German Energy Priorities
    btw I just updated the post. Germany has recently passed laws to increase its share of renewable energy production from 17% to 35% of total production by 2020. That's not quite enough to replace all nuclear power (about 23%), however. I suspect they'll be replacing come aging coal plants with natural gas over that period as well.
  35. Google It - Clean Energy is Good for the Economy
    scaddenp: I can think of one area close that has no dams on it right now. Yellowstone River. In my travels, I know the Missouri could have more dams. The wet cycle has been present for 20 years, and is projected to last another 60-100 years. Might as well take advantage of that. The dams would not have to be huge. A 100 MegWatt dam here, another there, and pretty soon we are talking major energy production. No one up here puts a fuel oil furnace in anymore. Most have gone to high eff LP or natural gas if available. Depending on location, (high ground water), a lot of geothermal have also been installed. North Dakota has been promoting this for a number of years. North Dakota Eduction
  36. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @225, please follow the logical steps: 1) Increased temperature implies increased specific humidity; 2) Increased specific humidity implies more water condenses as a result of cooling due to updrafts or frontal systems; 3) More water condensing implies more latent heat released; 4) More latent heat released implies a stronger updraft generated which: 4a) Results in greater cooling, with more water released; and 4b) Results in more air being drawn into the updraft, carrying more water with it. Please note that there is no contradiction between 4 and 4a. Although more heat is released, the updraft cools the air rapidly as it rises. The consequence is that where updrafts form, the moister the air, the stronger the thunderstorms that result, as in stronger winds as more air is drawn into the updraft, more intense rainfall as more water is precipitated out in a single column, more hail as precipitated water is carried to a greater height by the strong updraft before falling, and larger drops (and hence hail) as condensation is more rapid so fewer seeds are used, and more drops coalesce by collision. That is an observable pattern in weather systems quite independently of any considerations of global warming. It also makes the prediction of more, and more intense thunderstorms a straightforward consequence of global warming. There are complications relating to changes in weather patterns making some areas drier. There are also complications relating to the spawning of the most damaging convective storms, ie, tornadoes and hurricanes/typhoons/cyclones. The increased strength of convection is why the increased rainfall for the most intense 5% or 1% of rainfall events is expected to be much larger than 4% for a 4% increase in specific humidity. Turning to your height analogy, which I like, but which should be used cautiously; if the average height increases but variability remains unchanged, then the occurrence of more extremely tall people by the old definition of extremely tall will increase. Indeed, this effect will occur for any definition of "extremely tall" which is greater than the increase in average height. Consequently it does not matter whether you use a definition of 2 SD deviations above the original mean height, or 4 SD. Both are expected to increase. The only significant difference is that the 2 SD definition gives you a larger sample of "extreme tallness" to test for any increase. That is a crucial point. The effect of insisting on the more extreme definition is only to reduce your sample size, and hence make the data noisier. As it is, weather bureaus have definitions of "extreme weather" based on a simple metric - is the weather such that people should be warned about a risk of loss of life or property. If it is, its extreme. If it isn't, it isn't. That is a low bar in terms of return periods, but it is very practical for people receiving forecasts. Somebody receiving an "extreme weather warning" does not care how many standard deviations from the mean, or what the return interval is. They care about whether they should get their car under cover, or whether they are at risk from flash flooding. Well, global warming predicts that "at risk" episodes due to weather will increase. That is the hypothesis. For statistical convenience for some types of events (precipitation, thunderstorms) it is convenient to look at changes in return intervals to test that theory. For others (tornadoes and hurricanes), you just count the tornadoes and hurricanes and their relative intensity. Given that global warming predicts an increase of "at risk" episodes, defining "extreme" to mean "at risk of major catastrophe" episodes only reduces your statistical sample. It is a ploy to hide from the evidence. Nothing more. And on a side note, I (and I suspect Bérenyi Péter) are not experts in statistics (although Bérenyi is certainly much more competent than I am in that area). In contrast, Dikran is a genuine expert on statistics. To the extent that I am expert on anything (which I do not claim for anything) it would be logic and the use of words to convey meaning (philosophy of language).
  37. German Energy Priorities
    It will be interesting to see how the Germans do. I really wish they would prioritize phasing-out coal first. If they can accomplish a phasing-out of both coal and nuclear at the same time, more power to them (no pun intended), but I'm skeptical (as is Chancellor Merkel).
  38. Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Back in 1967 my dad and I went for a drive from Cairns up to Port Douglas (which was then a run-down fishing village) along the coast. I remember seeing corals that came right up to the shore. However, when I repeated that trip in the mid 2000s there were no corals along the coast.
  39. Great Barrier Reef Part 1: Current Conditions and Human Impacts
    Looking forward to the second part of this series. Agricultural runoff and overfishing have both done great damage - prawn trawling methods used on the central Queensland coast can be likened to clearfelling of the sea bed and harm biodiversity due to large amounts of bycatch. Add warming and acidification into the mix and I can't see a rosy future.
  40. Climate's changed before
    Thanks Stephen Baines for your encouraging reply. I replied on this threat because that’s where E Sat’s post appeared. I will take the advice of the moderator, make some changes to the post, and place it on the infographic thread. Thanks moderator! A final thought, however, on the ‘climate’s changed before’ argument. By using the term ‘natural climate forcings’ for what we can observe in the past as opposed to ‘man-made’ global warming now, we reinforce the division between man and nature that has helped precipitate the crisis. (Anthropocentric is better word technically but doesn’t avoid the problem.) It seems important to stress that man’s activities are as much a natural force as any other. We are the volcanoes of the age. It is because we are an intrinsic part of nature that we can have such a profound impact on the planet. By accepting language that separates man from nature we are, conceptually, partly buying into the denier illusory worldview.
  41. German Energy Priorities
    JMurphy #5 A very broad statement. Which I very cautiously agree with. But we are a long way from talking about renewables displacing nuclear. And it's not something that will wait.
  42. A Detailed Look at Renewable Baseload Energy
    Moderator #122 Apologies for overstepping the mark. I took my measure of what is acceptable from this:
    I get enough irrationalism on this site from the deniers. I don't need another source as well.
  43. German Energy Priorities
    Nothing IS off the table, which is why nuclear must take its place as we move away from oil and coal. But nuclear is NOT the future, either : renewables are and will be. The sooner we can move to 100% renewables, the better. How we do that is an ongoing struggle.
  44. German Energy Priorities
    JMurphy We both want the same thing: rapid global decarbonisation. Let's debate the fundamentals reasonably. Nothing off the table.
  45. German Energy Priorities
    JMurphy Quoting Savacool #2
    Any rational investor, regulator, and citizen would choose instead to invest in the deployment of technologies that require little to no energy inputs so as to harness free and clean fuels widely throughout the world. Policy makers should peek beyond the smoke-and-mirrors Kabuki dance used to obscure the obvious advantages of renewable technologies and the obvious costs of nuclear systems. Any effective response to electricity demand in a world facing climate change involves enormous expansion in our use of renewable technologies and a steady abandonment of nuclear power.
    This would be true if there was a convincing argument that renewables provide a more efficient path to rapid decarbonisation than does nuclear.
  46. German Energy Priorities
    Another, more up-to-date, article from B.K. Savacool makes interesting reading too : This article judges modern nuclear power and renewable electricity technologies according to six criteria: cost; fuel availability; land degradation; water use; climate change; and safety/security. It concludes that when these criteria are taken into consideration, renewable electricity technologies present policy makers with a superior alternative for minimising the risk of fuel interruptions and shortages, helping improve the fragile transmission network and reducing environmental harm. As does this article, from him too - The ªSelf-Limitingº Future of Nuclear Power" : Any rational investor, regulator, and citizen would choose instead to invest in the deployment of technologies that require little to no energy inputs so as to harness free and clean fuels widely throughout the world. Policy makers should peek beyond the smoke-and-mirrors Kabuki dance used to obscure the obvious advantages of renewable technologies and the obvious costs of nuclear systems. Any effective response to electricity demand in a world facing climate change involves enormous expansion in our use of renewable technologies and a steady abandonment of nuclear power.
  47. Dikran Marsupial at 07:27 AM on 4 July 2011
    2010 - 2011: Earth's most extreme weather since 1816?
    Norman, take a GCM, which embodies our knowledge of climate physics. Apply CO2 radiative forcing, and observe an increase in rainfall frequency and intensity. Does it then become science? The obvious google search gave this example. I suspect there are more.
  48. Google It - Clean Energy is Good for the Economy
    Well Camburn, the point of carbon tax is to change the economics of things like oil-central heating versus non-carbon alternatives. That is the crux of its effectiveness. Biofuel is the other alternative for long range transport. Beside small-scale stuff like sewage-farm "cogen", capturing CO2 from steel-making and pushing that into algal diesel is an interesting idea. 2nd gen crude oil from wood might be interesting too. While these arent economic against current oil price with carbon tax, I doubt carbon tax will be necessary within 10 years. Hydro is major component of our electricity industry (75% renewable and growing) but sadly I am not so sure about its viability in much of US. The crucial element of being able to create a high fall with high water flow seems missing for much of US topography but it would be great if I was wrong.
  49. German Energy Priorities
    This is well put:
    Thus from a logical and scientific standpoint, Germany should first phase-out the use of more dangerous and environmentally damaging fossil fuels before pursuing a phase-out of nuclear power. Unfortunately the German public has its priorities backwards, phasing-out the energy source which poses less of a threat to both public health and the global climate.
    It's worth bearing in mind that Germany is already barely coping:
    The four German TSOs have indicated that the nuclear power moratorium is having a significant impact on the German electricity supply system. Sufficient security of energy supply may not be guaranteed in southern Germany on very cold winter days with concurrent low wind power generation. Section 11(1) of the German Energy Act (EnWG) obliges transmission system operators (TSOs) to operate a secure, reliable and capable energy transmissions system without discrimination. Furthermore, they are obliged to maintain the system, to optimize it in line with demand, to strengthen it and to expand it, to the extent this is commercially reasonable. However, as unbundled TSOs do not generate the electricity, and as recent shutdowns are limiting German generation capacity, the German TSOs are facing a challenge to comply with their obligations. As a result of the Fukushima moratorium and scheduled revisions, only 4 of the 17 German nuclear power plants are currently online. Favourable conditions (low network load, strong solar, but rather low wind power input) and system operator interventions have so far made it possible to maintain network stability, the TSOs pointed out. Assuming no unusual events, the situation shall presumably be manageable also for the summer period, the four TSOs (Amprion GmbH, 50Hertz Transmission GmbH, EnbW Transportnetze AG and Tennet TSO GmbH) said. However, stability will require using every possibility form of redispatch measures, interventions in the electricity markets, to postponing urgent grid maintenance and expansion projects as well as power plant revisions, they added. The TSOs also indicated that the free electricity market will be suspended for considerable periods of time. Still the risk of power failure has increased, the TSOs said. In case input capacity remained reduced by 8,000 MW after the end of the 3-month nuclear power extension moratorium (on 15 June 2011), TSOs foresee problems in particular for the coming winter months, as the possibilities for interventions were largely exhausted. In (industrial) southern Germany the electricity demand might not be satisfied on cold cloudy winter days with a low wind power input in northern Germany. 2,000 MW of secure generation capacity would be missing in southern Germany. Demand might also not be covered by electricity imports if other countries consume their electricity output themselves. As a consequence the risk for large power outages will increase, the TSOs warned.
  50. Dikran Marsupial at 07:18 AM on 4 July 2011
    2010 - 2011: Earth's most extreme weather since 1816?
    Norman@227 Yes, that is the point, it was you that was mistakenly talking about proof. In the case of linking mechansims, these are well known to hydrologists. Knowing the mechanisms however does not mean that you can accurately predict something. You can write down the physics of a double pendulum on a side of A4, but you can't predict it exact course. Does that mean we can only have opinions about double pendulums, but not science? Of course not. You appear to have a rather unusual definition of science.

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