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Camburn at 04:35 AM on 25 June 2011Linking Extreme Weather and Global Warming
Albatros@206: We are in a global ag market with 3 grains being the main ones traded. Soybeans/Corn and Wheat. Brazil is a major player in Soy/corn.....Agentina soy/wheat. The US is a major player in all of them. Rainfall affects production in Brazil/Arg just as it does in the USA. All of this affects the world markets prices. That is how it affects my business. -
Paul D at 04:34 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Norway is I believe almost totally hydro-electric which isn't practical for most nations/regions. Power generation is not the only issue as Okatiniko says. We are talking about system design from generator to home or factory. The load(s) have to be balanced with the power source(s) otherwise the grid/mains frequency starts drifting. In fact one of the key ways that a smart grid would work is buy monitoring the frequency so that intelligent appliances can alter their use of energy. -
Eric the Red at 04:24 AM on 25 June 2011Linking Extreme Weather and Global Warming
JMurphy, Of course, we in the North know that adage well. A few notes on your post. Heavier snowstorms occurred in wetter winters sounds self-evident, and has no relation to temperature. The Changnon study was restricted to heavy snowstorms. Their graph of snowstorms (which may or may not correlate with seasonal snowfall) shows that snowstorms were lowest in the three decades from 1920-1950, and highest in the 1910s, and 1960-1980. Roughly corresponding to the high and low temperature decades (the exception being the 1990s). The heaviest snowfall occur when the temperature hovers around freezing. Colder temperatures tend to result in lower snowfall totals. The report did not mention total seasonal snowfall. -
Tom Curtis at 04:06 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric (Skeptic) @102, David Archer has studied this issue extensively. He shows that if we release 2000 Gigtonnes of CO2 into the atmosphere, then in a thousand years, atmospheric concentrations will still be elevated by 29% of that value, and by 14% after 10,000 years. He also shows an interesting graph correlating global temperatures with sea levels from geological records: (As adapted here) -
Bibliovermis at 04:05 AM on 25 June 2011Linking Extreme Weather and Global Warming
My guess would be that is where his planting stock comes in from. -
actually thoughtful at 03:52 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Okatiniko - You say that Norway already has 100% renewable energy, then you say computer simulations that say you can run a country on 100% renewable are wrong. Can you clarify your point? -
Albatross at 03:51 AM on 25 June 2011Linking Extreme Weather and Global Warming
Camburn, A long time ago you stated in a discussion with me that: "I am most interested in Argentina/Brazil as weather patterns in that area directly affect my business." With you being a farmer in N. Dakota, how does rainfall in Argentina/Brazil directly affect your business? -
SouthWing at 03:51 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
“The very first step should be for climate scientists to make a conscious effort to read some of the documentation appearing in the more respectable sceptic weblogs,” he argued. Hmm..."respectable sceptic weblogs"... Nope, sorry: can't think of a single one. -
Composer99 at 03:44 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
okatiniko: {citations needed} -
rocco at 03:43 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
okatiniko: Your contribution here will be much more valuable if you actually bother to read your posts and make sure they make sense before you hit the submit button. -
Tom Curtis at 03:42 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
michael sweet @105, given sufficient low entropy energy, in principle everything is reversible (except perhaps plate tectonics). We could even resurrect the dinosaurs in principle, although it would probably take fifty years research to develop the correct techniques. We would certainly be able to resurrect all of the many species expected to go extinct over the next century - if we where prepared to devote enough resources to it. Should we desire, we could even spray sulfates in the upper troposphere above greenland, and "crop dust" the surface with fresh water to recreate the ice sheet and glaciers. What we can't do is reverse anything except the smallest changes cheaply. We can't reverse anything significant except at a far greater cost than the cost of preserving it in the first place. And what is more, given the likely impacts of BAU, in fifty years we won't have the spare resources to even think about reversing anything. Contrary to Eric's claim that he was responding to you when he made his comment about reversibility, it was actually a response to my claim that effective action had a used by date of 2020 @86 (see his 87). As such, it was an empty rhetorical sally to divert attention from my point and should be allowed to die a quiet death. -
Composer99 at 03:41 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
The "Galieo Gambit" in action. What climate science "skeptics" (along with anyone else who attempts to score rhetorical points with this gambit) forget is that it is not enough to espouse a position contrary to the consensus of experts. One must also be right. The contrarians have manifestly failed in this latter regard. Indeed, they are not even persecuted the way Galileo was (that fate is, it seems, reserved for climate scientists). -
Albatross at 03:25 AM on 25 June 2011Linking Extreme Weather and Global Warming
JMurphy You are quite right about what constitutes "precipitation". -
Albatross at 03:25 AM on 25 June 2011Linking Extreme Weather and Global Warming
EricS and Camburn, While management of river flows and dams is obviously critical in these situations and sometimes bad decisions are made. Have either one of you paused to actually consider why we have all this water on the ground to manage in the first place? This cannot mostly or all be blamed on officials guys, the primary reason for this situation is that the Northern Great Plains have been receiving record-breaking rains at a time when the soils are saturated, dams are full and rivers swollen. But yes, let us ignore those very real and critical factors and take our anger and frustration out on officials. And both of you seem to be forgetting that rivers are breaking previous records on the order of metres. No, no, nothing unusual going on here at all. I have stated before that people in denial about AGW can and will be knee deep in water and still be claiming that 1) It is OK, this happens all the time, nothing unusual here, or 2) This is happening because of something else unrelated to AGW. With all that said, Camburn, keep safe. PS: Camburn earlier I gave you the Chagnon details to look up trends in thunderstorms and associated phenomena, but you seem to have used it to go on a very different tack. -
okatiniko at 03:24 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Norway has already a 100 % renewable electricity , and other countries such as Iceland as well, and other such as France have an almost carbon free nuclear power. The issue is not only power generation, but power USE. Computer simulations may prove that it is possible to use only electricity and biomass - reality proves that computer simulations are wrong. -
JMurphy at 03:19 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red wrote : "I find no one in the Hansen report were he says that the amount of CO2 added to the atmosphere today is enough to raise sea levels 5m." Why were you looking for such a scenario in that report ? -
actually thoughtful at 03:08 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
I applaud Skeptical Science's work on debunking these myths that state, in essence, "there is nothing we can do about it anyway". There is, and many, many individuals and companies are taking steps on their own initiative, in light of the global failure of governments to respond. -
Albatross at 03:07 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
EricR @96, "The IPCC predicted that it would take a 5.5C temperature rise to melt Greenland, and it would take several centuries. Recent studies show that the melt rate is significantly less." That statement is demonstrably wrong. Your biased interpretation of the papers (which you don't seem to really understand) have been addressed by Michael and Skywatcher, and you did not recognize your error, ignored their insights and just tried to re-frame your argument and shift the goal posts @100. Doing so is incredibly ungrateful, people are trying to help you understand this better, but you appear to have too many mental hurdles/blocks (and no I am not saying you are dim or anything like that) in the way I doubt you even followed the link to Tamino's statistical analysis of Arctic sea-ice volume. Monthly Arctic sea-ice volume anomalies: September Arctic sea-ice volume anomalies with quadratic fit: Source] -
michael sweet at 02:38 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, What about my questions about reversibility here?? You have chosen one of my comments and ignored the rest. You claimed that nothing is irreversible. What will reverse the flooding, drought, fires and ocean acidification that already exist? Your claim that all is reversible is not supported by showing that it is not yet known how much sea level will rise in the next few decades. It may just as well be true that sea level will rise more than 2 meters by 2100 as that it will be less than 1 meter, uncertainty cuts both ways. Your choice of only the most optimistic models is unlikely to hold up. -
Albatross at 02:36 AM on 25 June 2011Sea Level Hockey Stick
BP @94, "Anyway, this GIA thing only gives a -0.3 mm/year contribution to sea level rise." Well there you have it folks, BP agrees with the University of Colorado, and refutes the ridiculous assertions being made here. -
Albatross at 02:27 AM on 25 June 2011Sea Level Hockey Stick
BP, I commend your obfuscation efforts @80. On the surface of it, and ignoring your unsubstantiated hypotheses and musings, you may (or may not) have a out about the GIA correction. Can we look forward to you writing up and submitting a formal rebuttal to the journal, or are you simply here to grandstand? But before that, perhaps we should show what they actually say in the paper: "A constant rate of subsidence (with no error) was subtracted from the Sand Point (1.0 mm/y) and Tump Point (0.9 mm/y) records. These rates were estimated from a US Atlantic coast database of late Holocene (last 2000 y) sea-level index points (13, 15). Use of a constant rate is appropriate for this time period given Earth’s rate of visco-elastic response (14). The resulting records are termed “GIA-adjusted,” expressed relative to mean sea level from AD 1400–1800 and visually summarized by an envelope (Fig. 2C)." So a constant correction was applied to all the data, and just as if a temperature sites has a systematic bias, that systematic bias/offset does not affect the trend.Moderator Response: [Dikran Marsupial] Please can we all dial back the tone of the discussion a notch or two, and keep things on a constructive a level as possible. -
pbjamm at 02:26 AM on 25 June 2011Sea Level Hockey Stick
Camburn@74 It is right there in the OP: "IPCC AR4 showed that local sea-level trends differed by up to 2 mm/y from the global mean over AD 1955–2003, which implies deviations of up to ±10 cm at some locations (but ±5 cm along most coastlines) as the sum of forced and unforced effects. This analysis suggests that our data can be expected to track global mean sea level within about ±10 cm over the past two millennia, within the uncertainty band shown for our analysis." So if I am understanding it correctly, this regional proxy is average when compared to global proxies. Not everyone can be a unique snowflake! On the Bell Curve someone has to be average. -
Berényi Péter at 02:13 AM on 25 June 2011Sea Level Hockey Stick
The only process that has a measurable effect on ocean basin volume is GIA (Glacial Isostatic Adjustment). Currently volume of ocean basins is increasing at a 100 km3/year rate, because vast continental areas that were once covered with miles of ice, having got rid of this weight, started rising. It can only happen if mantle material (which behaves as a high viscosity fluid) is sucked in from below the oceans to support rising rock. That is, ocean basins next to previous ice sheets (like the Laurentide and Fennoscandian one) are getting progressively deeper. All other processes like plate tectonics or sedimentation operate on much longer time scales and their contribution is negligible to millennial rates of ocean basin volume change. Anyway, this GIA thing only gives a -0.3 mm/year contribution to sea level rise. As for ocean water volume changes, relative sea level measurements at continental margins (tide gauges) are not representative, because continental margins themselves are sinking on average. There are two reasons for that. One is still GIA, because sea level is some 120-140 m higher now than it was twenty thousand years ago. This additional weight of seawater is slowly pushing continental margins down (relative to the true geoid). The other one is ground water depletion which (through decreasing pressure in water table) induces sinking of sedimental layers in many coastal regions. Therefore part of sea level rise as measured by tide gauges is in fact (coastal) land level decrease. Volume of sea water can change in two ways. One is steric when water mass is unchanged and only its volume changes due to decreasing (or increasing) density, mainly because of changes in heat content. In this respect sea level behaves as a thermometer. Not a terribly good one though, because volumetric thermal expansion coefficient of seawater depends heavily on both temperature and pressure, so the addition of the same amount of heat can produce quite different sea level changes depending on which part of the ocean absorbed it. As volumetric thermal expansion coefficient is increasing with both temperature and pressure, while water temperature decreases with depth, there is a layer at about 1000 m below the surface where absorption of heat has the least effect on sea level. Expansion due to the same amount of heat absorbed increases both below and above this level (the former because of increasing pressure, the latter because of increasing temperature). The other way to change sea water volume is to change its mass, that is, to add some more water to the oceans or subtract it from them (and store it elsewhere). The main processes here is melting of land based ice (or snow accumulation), water storage in reservoirs (negative contribution) and groundwater depletion. These processes do not have much effect on heat content of the climate system. The last two has simply none, while melting ice uses almost a hundred times less heat to produce the same sea level change as (steric effect of) heat absorption by water. ( -Snip- )Response:[DB] Off-topic unsupported conclusions snipped.
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Albatross at 02:08 AM on 25 June 2011Sea Level Hockey Stick
"When dot-cloud radar scanners can penetrate 3700m of seawater and measure the bottom to an accuracy of 0.1mm, we could determine if the bathtub is growing or shrinking in volume. If the bottom was rising 1-2mm per year - there is your SLR." Surely they jest? What a lovely red herring. Occam's razor applies here, and some would rather have us debate how many angels can dance on a pin head, rather than face the fact that the global sea levels are rising in step with increasing temperatures as they have in the past (and here I mean over statistically significant periods of time). This paper has obviously causing "skeptics" and those in denial about AGW some cognitive dissonance and their posts here show that. Posts such as the one I quoted above are trolling and baiting, and nothing to so with the paper being discussed. It is also a perfect example of how someone in clearly denial can rationlize what they so dearly wish to believe. That is not science either. They are also examples of fabricating doubt, confusion and exaggerating uncertainty, claiming that "we do not know everything so we know nothing" all tricks routinely plied by the "skeptic" and denialist misinformation machine. Can we please get back on track folks. -
skywatcher at 02:07 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, is the trend in sea ice volume or in minimum sea ice extent linear or nonlinear? And please do not insult everyone's intelligence by suggesting that the trends are based on 'one or two points'! These things can and indeed have been assessed properly, and we do not need to rely on your 'anticipation' to evaluate the shape of the current trend. -
Eric the Red at 01:55 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
JMurphy, I find no one in the Hansen report were he says that the amount of CO2 added to the atmosphere today is enough to raise sea levels 5m. -
Eric (skeptic) at 01:51 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
#92, moderator, if went to zero tomorrow CO2 would immediately exponentially decay to half way back to 280 in less than 48 years. There is simply no other possibility considering how much we have put in the atmosphere and how much remains. I posted a simple spreadsheet showing this here: https://www.iwork.com/document/en/?a=p1415598010&d=CO2growth.numbersModerator Response: [Dikran Marsupial] You would indeed get a fairly swift reduction half way back to the pre-industrial level (although 48 years would be an optimistic estimate IIRC), however the decay would not be a simple exponential and the reduction to a quater of the way to the pre-industrial equilibrium would take very much longer. -
JMurphy at 01:15 AM on 25 June 2011Renewables can't provide baseload power
rcglinski, did you actually read the report that the graph came from ? In it, it states this : In 2050, energy demand is 15 per cent lower than in 2005. Although population, industrial output, passenger travel and freight transport continue to rise as predicted, ambitious energy-saving measures allow us to do more with less. Industry uses more recycled and energy-efficient materials, buildings are constructed or upgraded to need minimal energy for heating and cooling, and there is a shift to more efficient forms of transport. Now, straight-faced or otherwise, what are your arguments against that ? For further information, read the report, especially from page 44. -
dorlomin at 01:06 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Great article, lot to digest. -
rcglinski at 00:57 AM on 25 June 2011Renewables can't provide baseload power
The very first graph has global energy consumption peaking soon and then declining. That doesn't pass the straight face test. -
J. Bob at 00:37 AM on 25 June 2011Sea Level Hockey Stick
Ken Lambert @ 89, says "When dot-cloud radar scanners can penetrate 3700m of seawater and measure the bottom to an accuracy of 0.1mm, we could determine if the bathtub is growing or shrinking in volume. If the bottom was rising 1-2mm per year - there is your SLR.". That was my point at the end of #48. There is still a lot we have little knowledge of, including sea floor topography. -
JMurphy at 00:34 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red wrote : "My comments were to counter michael's claims that if we stopped emitting CO2 today that temperatures would continue to rise dramatically, resulting in several meters of sea level rise." Are you referring to michael sweet's comment at 91 ? If so, I can see no use of any form of the word 'drama' and he links to a paper by Hansen et al which predicts a sea-level rise of up to 5m. What would you call 5m, if not 'several' ? Can you specify where your use of the word 'dramatically' comes from (or withdraw it, if you can't), and show how your argument against Hansen et al is backed by peer-reviewed research. -
Eric the Red at 23:53 PM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
All, My comments were to counter michael's claims that if we stopped emitting CO2 today that temperatures would continue to rise dramatically, resulting in several meters of sea level rise. My point was that nothing that has happened to date is irreversible. No one has presented anything to dispute that contention. Speculating that future events will happen does not constitute evidence. What is the best way to predict the future? Simple, by looking into the past. Some may call this optimistic, becasue I am not anticipating acceleration in the trends. Can you actually say something is accelerating based on one or two points? Do you reason to believe that the trend is nonlinear? -
JMurphy at 23:50 PM on 24 June 2011Linking Extreme Weather and Global Warming
Eric the Red wrote : "Overall, AGW predicts greater precipitation, but not snow." Precipitation is precipitation, whether it falls as rain or snow, and others here have already shown how snow can be more likely, depending on local or regional conditions. More information and links available from Jeff Masters : Another interesting result from the Changnon et al. (2006) paper of Figure 2 is the relationship between heavy snowstorms and the average winter temperature. For the contiguous U.S. between 1900 - 2001, the authors found that 61% - 80% of all heavy snowstorms of 6+ inches occurred during winters with above normal temperatures. In other words, the old adage, "it's too cold to snow", has some truth to it. The authors also found that 61% - 85% of all heavy snowstorms of 6+ inches occurred during winters that were wetter than average. The authors conclude, "a future with wetter and warmer winters, which is one outcome expected (National Assessment Synthesis Team 2001), will bring more heavy snowstorms of 6+ inches than in 1901 - 2000. The authors found that over the U.S. as a whole, there had been a slight but significant increase in heavy snowstorms of 6+ inches than in 1901 - 2000. So, there is evidence that the average climate of the U.S. over the past 100 years is colder than optimal for heavy snow events to occur. If the climate continues to warm, we should expect an increase in heavy snow events for a few decades, until the climate grows so warm that we pass the point where winter temperatures are at the optimum for heavy snow events. However, a study by Houston and Changnon (2009) on the most severe types of snowstorms--the "top ten" heaviest snows on record for each of 121 major U.S. cities--shows no upward or downward trend in the very heaviest snowstorms for the contiguous U.S. between 1948 - 2001. And Joe Romm : Research says big snow storms not inconsistent with — and may be ampliflied by — a warming planet -
Tom Curtis at 23:50 PM on 24 June 2011Sea Level Hockey Stick
Ken Lambert @90, "I am not going to check your sums this time Tom, but I do wonder why you present such an array of number facts and then cast doubt on your own sums which are supposed to make your point." Because, KL, unlike you I would rather arrive at the truth than make a point. That is why I can admit my errors, while you give every evidence of being incapable of doing so. -
Ken Lambert at 23:41 PM on 24 June 2011Sea Level Hockey Stick
Tom Curtis #84 Sediments are a very small contributor globally - less than 0.2mm/annum by my rather old sum extrapolating the Yangtze River flow. "Please by all means check my maths as I am notorious for errors in that area, but this simple reality check suggests there is no significant impact on ocean volume by sedimentation" I am not going to check your sums this time Tom, but I do wonder why you present such an array of number facts and then cast doubt on your own sums which are supposed to make your point.Moderator Response: [Dikran Marsupial] Please stick to discussing the science, rather than comments regarding the motives of the participants. As this is an area where you have tended to sail rather too close to the wind with respect to the comments policy, it would be well worth refraining from such comments entirely. As it happens, explicitly stating any uncertainties in ones argument is standard operating procedure in the sciences. "If a man will begin with certainties, he shall end in doubts: but if he will be content to begin with doubts, he shall end in certainties" - Francis Bacon -
Ken Lambert at 23:32 PM on 24 June 2011Sea Level Hockey Stick
Tom Curtis #84 BP#80 BP seems to me making good unanswered points. This whole SLR debate should be reframed as a VOWIO (volume of water in oceans) debate. Because that is the real measure of warming via thermal expansion and ice melt. I did some numbers a while ago on sediments and biomass - and they were one or two orders of magnitude smaller than the 2-3mm/year of SLR. When dot-cloud radar scanners can penetrate 3700m of seawater and measure the bottom to an accuracy of 0.1mm, we could determine if the bathtub is growing or shrinking in volume. If the bottom was rising 1-2mm per year - there is your SLR. -
CBDunkerson at 23:18 PM on 24 June 2011The chief troupier: the follies of Mr Monckton
Ken wrote: "Al Gore's movie "An Inconvenient Truth" was found unfit for use as an educational tool..." More fiction. An Inconvenient Truth continues to be distributed in the UK as educational material. The judge in the Dimmock case (which you presumably refer to) found that it was "substantially founded upon scientific research and fact" and thus allowed for use in schools. The judge did require that a 'guidance' document accompany showing of the film to inform students that a few parts of the film expressed views which were still disputed by some skeptical scientists. Seriously, don't you ever get tired of being lied to? As to Williams... you now argue that he has a closed mind because he didn't read the 'Climategate' letters. That's arguable... but very different from your assertion that he (among others) is guilty of outrageous claims and distortions. For which you have still provided no examples that are not demonstrably false. -
Argus at 23:14 PM on 24 June 2011Sea Level Hockey Stick
#86 ... and also, on the other hand, that many commentators on this site seem to get genuinely happy for every new hockey stick that shows up!Moderator Response:[DB] I'm extremely certain that every single regular poster here would like nothing more than for a "silver bullet" to be found that makes the entire problem of the radiative physics of our fossil fuel emissions "go away". But being human, there is a natural tendency towards elation when we have solid scientific data showing the dissembling of the denialist movement to be exactly what it is: a house of cards built on shadows and myths.
[Dikran Marsupial] Proof that every cloud has a silver lining, even if it is only one atom thick! ;o) -
pauls at 22:53 PM on 24 June 2011Sea Level Hockey Stick
81, okatiniko - I realise this ha been declared OT but thought I'd make you aware of some developments since that 2004 paper. This is a comment on the paper published in 2006 pointing out errors in their methodology. Further discussion here. -
Marcus at 22:36 PM on 24 June 2011IPCC Report on Renewable Energy
Hey Rob, I'm totally with you on this-trust me. I was simply making the point that the coal industry-both in the US & Australia-rarely even *try* to rehabilitate the land they destroy, which is one of the reasons their costs are so low. Now they want to risk polluting our ground water by switching to *fracking*! Time to send this dinosaur of an industry into extinction! -
skywatcher at 22:31 PM on 24 June 2011Sea Level Hockey Stick
Methinks that some around here, and presumably on certain well-known blogs really don't like hockey sticks showing up in different kinds of palaeoclimate records... -
sgmuller at 22:30 PM on 24 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
Where I first heard about the Galileo Movement I immediately thought that we could add a third bit of advice to an old saying. "Never play poker with a man called Doc, never eat at a place called Mom's and never trust a science organistaion calling itself the Galileo Movement." -
skywatcher at 22:21 PM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, from your own linked article about Greenland: "Richard Alley of Pennsylvania State University cautions that Price’s model does not provide an upper limit to sea level rise." Additionally, while I do not of course expect Greenland to disappear within my lifetime, the point is that we are setting up a chain of events that will not just reverse with a slight decrease in CO2. As for sea ice, try this discussion of sea ice volume. Do you think trends in Arctic sea ice are or are not showing accelerating declines. When does the acceleration show most clearly - when ice is thickest, or when ice is thinnest? Do you think you can put a straight line through data points (with no mechanical/physical reason why) and say that this will be the trend in the future? It would be nice to have your optimism, but real physical systems do not operate in the simplistic way you would like them to behave. -
Rob Painting at 22:18 PM on 24 June 2011IPCC Report on Renewable Energy
Land rehabilitation?, what about river and stream rehabilitation? And what the heck does 'rehabilitation' really mean anyway?, it can't realistically be rehabilitated. Those areas will be stuffed for generations. I really do hate it when polluters try to minimize the damage they cause by using weasel words. -
Marcus at 22:12 PM on 24 June 2011IPCC Report on Renewable Energy
Here's an interesting quote to put Quokka's claims about land use into perspective: "Based on current mining techniques, Mr. Nace says a solar thermal plant can produce 18 gigawatt hours per acre of land over a 60 year period; whereas a coal-fired power plant will generate 15 gigawatt hours per acre of mined land . This does not take into account the space required for toxic by-products such as fly ash. Compared to solar thermal, the land footprint of coal is about 20 percent greater." and this:"While in the US mining companies are obligated to perform restorative work after exhausting an area of coal, Nace says that this rarely occurs." Once again I wonder how much more coal would cost if these mining companies *did* have to pay for land rehabilitation? -
Marcus at 22:02 PM on 24 June 2011IPCC Report on Renewable Energy
Many sources of renewable energy are already comparable to subsidized coal on a price per kw-h basis. Small-Scale Hydro, Biomass Gas, Geothermal & On-Shore Wind.....and most of them take up very little land compared to coal. Even CSP & Photovoltaic Power are falling fairly rapidly. Yet Coal continues to have an unfair advantage because-in Australia for example-land rehabilitation & disposal of fly-ash waste are paid for by State Governments, they get free access to roads & rail, they get cheap water & a diesel fuel rebate. Without these subsidies, I doubt they could offer electricity for the price they currently do. I'd also say that subsidies are very important for relatively new industries-if only to help them achieve the economies of scale needed to get price reductions. My question is why should the coal & oil industry-both of whom are incredibly profitable-continue to receive significant tax-payer subsidies when it gives them such an unfair advantage in the energy market? -
Rob Painting at 22:02 PM on 24 June 2011The Last Interglacial - An Analogue for the Future?
Somes_J - just expanding a bit more on Steve's comment: because Earth's orbit was more eccentric (elliptical) back then, it's obliquity (rotational tilt relative to its plane of orbit) greater and the northern hemisphere summer coincided with perihelion (closest part of Earth's orbit to the sun), it meant the NH summer received greater solar heating than today. By contrast the Eemian winter would have been much cooler, so there would have been a greater difference between summer and winter temperatures in the NH (seasonality) this would have had a marked effect of the hydrological cycle at that time, such as the African Monsoon. See Herold 2009 for an examination of this issue. For the Holocene Climatic Optimum (HCO), once again astronomical factors meant a greater warming in the NH summer and a wetter African period. Changing orbital forcing, from the HCO to today, lead to a cooling in the NH and a change to the monsoonal pattern. As pointed out by Steve, the factors in play today are a bit different. Living in the world of the Eemian?, be nice if the world was as we'd like to be but even small changes in the global mean state, can mean drastic changes in extremes, such as rainfall intensity. The models do indicate that a warmer world is a wetter world, but that's an oversimplification, generally dry areas are expected to get drier (the south-western USA for example) and wet areas wetter, but again we expect greater seasonality even in wet areas the rainfall is expected to be in the form of less frequent rain, but much heavier downpours (i.e. bigger floods). Me personally, I'd like to avoid that future world. -
Dikran Marsupial at 21:48 PM on 24 June 2011Sea Level Hockey Stick
To add (very little) to what Tom says, there is also the point that sediment doesn't just sit at the bottom of the ocean, it gets compressed into rock and then gets subducted under continental plates. I suspect the rates of sedimentation and subduction are roughly in equilibrium on geological, in which case sedimentation would only cause a rise in sea level if there was a change in sedimentation rates. If there was a good reason to think sedimentation was an significant issue, you can be sure it would be taken into account in the adjustments made to the raw data. -
Tom Smerling at 21:46 PM on 24 June 2011IEA CO2 Emissions Update 2010 - Bad News
John A small addition might help make this (excellent) post more clear to the reader. When I reread the post this a.m., I noticed this: "Figure 4: Hadley Centre modeled warming by 2100 in various CO2 emissions scenarios (Source) "Right now we're on track with the orange and red arrows in Figure 4. If we continue with this business-as-usual high emissions path, the consequences could be dire. Some of the impacts listed in the IPCC report for global warming of 3–4°C above pre-industrial levels include...." But "orange and red arrows in Fig. 4" lead to + 4-5.2 C and + 5.5-7.1 C warming --- not 3-4 C. It's certainly OK to say "we'll let's just assume we're going to change our ways...and get back down to the "blue arrow" = + 2.9-3.8 C warming. But you should be explicit that you are switching scenarios in that paragraph. Different people might label that your assumption -- that humanity will acts "late and slow" to get back to the "blue arrow" where emissions return to 1990 levels by 2050" -- as either optimistic, reasonable or minimizing (a form of denial). But unless I am missing something here, it is simply confusing. One sentence in the above paragraph, noting why you are "switching scenarios" would take care of it.
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