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Comments 50951 to 51000:

  1. Latest summary confirms death of Chacaltaya glacier, and acceleration of global glacier shrinkage in the 2000s
    Kiwiiano asks about reduced snowfall. The critical factor in the demise of Chac' was cloud cover reduction since about 1980. No cloud means no snow replacement during the short snow season but crucially it means no shade from the intense tropical sunlight which, at that altitude drives very rapid sublimation of ice to water vapour. Sunlight warming peripheral rocks of the glacier would also have caused more melting than in earlier times. There isn't a weather station in the Chac' valley but near-by monitoring stations showed only margin warming and certainly not enough to melt ice significantly. One has to be careful to read widely and take into account all the variables and even then it is hard to draw solid conclusions. Sorry I've lost the link to this information now but it was from Bolivia,-The Monday Morning Newsletter or something like that and mostly written in Spanish.
  2. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    Tom Curtis@13 In baseball terms you just smacked a hard line drive that fracture the center-fielder's hand and bounced into the stands for a ground rule double; this, happening with two outs in the ninth, destroyed climateadj's no hitter. All that effort he put into his web site and you just shot him down in under a 1000 words. What is it they say about lies, damn lies, and inaccurate statistical interpretation with bias limits and false equivalency?
  3. The Latest Pre-Bunked Denialist Letter in Lieu of Real Science
    DSL@43 You can read the snipped text since it has only been commented out in the HTML. View the page-source. Sorry, can not contribute anything else of use to this thread.
  4. AGU 2012 - Solving the Climate Problem
    Eidolon, I'm not going to touch the population and immigration comments. However, for your heat argument, go here, read the main article, and then post any related questions or comments in that stream. Someone will respond. The combined comments stream is watched quite closely.
  5. AGU 2012 - Solving the Climate Problem
    Last night, I used the stove to make dinner. I then had a hot shower and, as it was cold last night, I put on the electric blanket. In other words, I was producing heat. If 7 billion other people are also producing heat on a regular basis then maybe global warming has little to do with CO2 output and more to do with billions of people simply producing heat and releasing it into the atmosphere.
    Moderator Response:

    [DB] No. You are off-topic on this thread. If you wish to continue this line of thought, please first read the post and all of the comments on this thread before commenting further. If so, please do so there, not here.

    Thank you DSL, for your sage advice and guidance to Eidolon.

  6. The Latest Pre-Bunked Denialist Letter in Lieu of Real Science
    Dang - I missed Brian's argument. I'm guessing it was Heartland par for the course: blah blah hoax blah blah liberal commie blah blah.
  7. Brian G Valentine at 07:47 AM on 12 December 2012
    The Latest Pre-Bunked Denialist Letter in Lieu of Real Science
    [Unproductive insult snipped]
    Moderator Response: [d_b] Please contribute comments at Skeptical Science to the extent you're able to further the conversation in a productive manner. If you're not able to be a useful part of the conversation, this is not a good place to spend your time writing comments.
  8. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Jim Baird - While a heat pipe avoids nutrient exchange, it's still a heat transfer in order to extract energy: cooling surface waters (increasing radiative imbalance) and warming deep waters (speeding deep ocean energy accumulation). As to the diurnal cycle, heat loss and gain are dependent on the gradient - more energy will be absorbed by a cooler ocean surface during the day, less emitted at night, and again an amplification of the radiative imbalance. OTEC may not be able to provide the warming mitigation you claim. This is, however, completely off topic for historic sea level rises. I would suggest a thread actually on geoengineering, such as this one.
  9. AGU 2012 - Solving the Climate Problem
    Ok, found the link on those colorful small banners... http://www.skepticalscience.com/climate_science_history.php
  10. AGU 2012 - Solving the Climate Problem
    SLATE has this nice little "very telling" graph on GW studies LINK Could someone here please point me to the SkS animation (with the bubbles) which does the same? Thanks.
    Moderator Response: [RH] Hot linked URL that was breaking page formatting.
  11. AGU 2012 - Solving the Climate Problem
    Thanks for the links to videos from the meeting. I haven't had a chance to watch Pierrehumbert's yet, but I hear it's excellent.
  12. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Doug it isn't likely we would ever be able to draw down the total 3C excess seen in the Atlantic this summer. Some of this heat will continue to radiate towards the poles and into space. OTEC would however convert a small portion of this heat to mechanical energy and would dump 20 times as much as we generate to the depths where it would be diluted in an environment where the coefficient of expansion is about half that of the surface. To the extent you draw down the surface heat you would diminish the strength of storms like Sandy that move heat into space and towards the poles, where it is melting the icecaps and the methane trapping permafrost. The TWHs not converted to mechanical energy are conserved but in a colder environment where they would do less damage in terms of sea level rise. KR, I advise using a heat pipe rather than a massive cold water pipe which moves cold water to the surface. Hurricanes use phase changes to move heat rapidly as does a heat pipe. The difference being the hurricane has the stratosphere as the heat sink as opposed to the abyss. As to radiative forcing the sea surface is subject to a diurnal heat cycle. It warms by day and cools by night. OTEC operates around the clock and removes heat from the surface by night as well as by day. Each morning therefore, IMHO, the surface would begin to warm from a lower base that without OTEC and since the same volume of water is being warmed by the same heat source, it seems to me, the diurnal high temperature should be less as well? Chriskoz, IMHO using a heat pipe rather than cold water pipe overcomes many of the environmental problems associated with OTEC and reduces the cost as well because for a 100MW plant you need a 1 meter diameter pipe rather than one of 14.5 meters. I have a patent pending for a system that uses a counter-current heat flow and metering system for the capture and governing of the return of the latent heat of condensation back to the surface both to limit the impact on the Thermohaline as well as maximize the amount of energy the ocean can generate. My thinking is in the long run it is best to convert as much ocean heat to work as possible, which requires the capture and return of the latent heat, but during hurricane seasons it is best to move as much surface heat to the depths as possible. OTEC can not be implemented on the scale I would like to see overnight. In the course of building it out we would have plenty of time to learn of the ramifications before doing any significant damage. I believe though it has potential for geo-engineering because it the process we would be producing all the carbon free energy we need. The input of those on this sight far more technically skilled than myself is appreciated.
  13. New research from last week 49/2012
    Thanks Ari!
  14. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    KR@18, OTEC would not necessarily worsen GW. You considered just the TOA energy imbalance. Let's consider carbon cycle feedbacks. Perhaps speeding the deep ocean circulation would increase the rate of CO2 intake, even speedup silicate rock weathering by 2 orders of magnitude to 100y timescale:) But I'm skeptical about OTEC feasibility. We know so little about the effects of such invasion into the ocean circulation, that we must learn alot before attempting such geo-engineering.
  15. AGU 2012 - Solving the Climate Problem
    And Real Climate has 5 videos from the AGU meeting Some AGU highlights 5 videos from AGU meeting im SF http://www.realclimate.org/index.php/archives/2012/12/some-agu-highlights/
  16. AGU 2012 - Solving the Climate Problem
    Some of the video'd talks are on youtube. Here are two I think you did not mention. A summary of the current science by Sir Bob Watson: Sir Bob Watson at AGU 2012 And what seeemed to be a high point for a lot of people - Ray Pierrehumbert on Succesful Predictions (and some unsuccessful ones) in Climate Science. Prof Ray Pierrehumbert at AGU 2012
  17. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Jim Baird - I'm a bit puzzled, here; how would bringing cold deep water up to the surface (to provide the temperature gradient needed for power generation) help with global warming? That would essentially bury warm water, reduce surface temperature and infrared radiation to space with surfaced cold water, and overall increase the radiative imbalance and the accumulation of energy in the climate. It would in fact increase the warming of the deep ocean while simultaneously increasing the rate of energy accumulation in the oceans as a whole. In other words, I suspect OTEC would (to a small amount - current energy use is 1% of the greenhouse imbalance) worsen global warming.
  18. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Not to be a jerk but how does the energy moved around by OTEC get transferred into space, Jim? I see your point and fully agree about mobilization on a large scale but it seems as though the Manhattan Project of OTEC would end up simply changing the respective profiles of the bulges in surface and ocean temperature we're creating. All the TWH are conserved, on Earth after all.
  19. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    Further to this, I noted ray pierrehumbert commenting on this issue at Realclimate (and attacking GWP as hopelessly broken). He points to this for analysis of coal versus of shale gas.
  20. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    That is interesting to know Tom. Not done in any mine I have had connection with, and I'd say impossible for any opencast coal mine.
  21. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Doug, Paul Curto, former Chief Technologist with NASA, recently pointed out, OTEC's impact on reducing the surface water temperature over time would be on the order of one degree F per decade at a power level of 2.5 terawatts. Sea surface temperatures running at over 3C above normal along the Atlantic coast from Florida to Canada where the driver for hurricane Sandy. Global warming is estimated to have contributed about 20 percent of this heat which would not have been available had we been producing 2.5 terrawatts of OTEC power the past 10 years. Kevin Trenberth points out, "With every degree C, the water holding of the atmosphere goes up 7%, and the moisture provides fuel for tropical storms. Five terawatts of OTEC power each decade would negate this increase. Five terawatts requires a lot of infrastructure but then so did the Manhattan Project and war efforts in general. I prefer to think that we should be on a war footing where global warming is concerned and so did over 70 percent of other Canadians in a poll a while back.
  22. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    scaddenp @11, some coal mine methane is extracted and used to generate power, or indeed, simply flared. While still lost to the atmosphere, it is as CO2 rather than CH4, and hence has a lower greenhouse impact.
  23. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    Son of Krypton @10 The current emissions of subcap methane are small when compared to some other human and natural sources, perhaps contributing less than 1% of total emissions today. Where the subcap methane releases may become significant is in the transient phase of permafrost deterioration, as pent-up methane is released when the permafrost sealing layer thaws and becomes perforated. I'll speculate on this in part four.
  24. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Pete@1: That was indeed an interesting read. Thanks for posting it!
  25. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    Not fun trying to measure CH4 emissions from coal mining either but its pretty easy to conclude that you have 100% loss of coal bed methane to atmosphere during the mining and processing. Before screaming too loudly about fracking I would like to some decent comparison of CO2e per GWh for coal versus shale gas.
  26. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    "Walter Anthony and her colleagues estimate that subcap seeps (seeps of fossil, thermogenic methane through discontinuous permafrost) may be currently emitting as much as 2 Tg of methane per year. This compares to an estimated seepage of 3-4 Tg per year for the rest of the world from surface seeps (excepting mud volcanoes)." Well, that certainly is disconcerting. Given that this rather enormous amount doesn't even take into account biological permafrost methane, one would think that it might just justify the IPCC including the permafrost carbon feedback in the AR5. Absolutely stunned me to learn that it was being left out
  27. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Jim, you'll want to compare the current volume of water being moved via routine overturning circulation w/the possibilities of OTEC. Down the road I suppose it's conceivable that overturning might become so sluggish as to need help but as it stands now the volume in play is quite astounding, about 575,000km3/year or ~1km3/minute for the Atlantic. Not sure if the Pacific is larger or smaller but let's assume bringing the Pacific into play doubles that number. A lot of infrastructure would be necessary to obtain a useful boost on those numbers.
  28. DIY climate science: The Instrumental Temperature Record
    thanks kevin I had not realized that they hadsst3 data only through 2006 :-b ... good to go on enjoying your wonderful application..
  29. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    The poles are warming faster than the rest of the planet because of energy in the atmosphere that is carried to the poles through large weather systems. The consequence is we have the threat of methane releases from the permafrost and icecap melting. These systems are driven in the main by sea surface heat which can be sapped to produce energy with OTEC. The more energy produced the more the ocean surface is cooled. Part of this heat is converted to mechanical energy in the process but the bulk, 20 times the energy produce, is moved to the deep water heat sink that has a lower coefficient of expansion. Kevin Trenberth, points out in a paper, "An imperative for climate change: tracking Earth's global energy", "The warming required to produce 1 mm SLR if the heat is deposited in the top 700 m of the ocean can take from 50 to 75 1020 J, or 110  1020 J if deposited below 700 m depth. In other words you can move heat from the surface to the depths with OTEC to counter 50 percent of current sea level rise due to thermal expansion. By sapping the heat of hurricanes you also diminish the amount of heat that would be moved from the tropics towards the poles and thus forestall melting. This is the lesson of Hurricane Sandy, no one apparently cares to learn. Disclosure - patents pending
  30. DIY climate science: The Instrumental Temperature Record
    Thanks Peter! I don't know if Javascript will handle the sheer size of the ISTI data, but I'll certainly give it a try if the data format is manageable.
  31. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    KR, I stand corrected. I did not go far enough back in her publicaton record.
  32. DIY climate science: The Instrumental Temperature Record
    This is really good stuff. We just released the second beta version of the databank for ISTI. See this blogpost which describes it. And earlier posts that characterize the first beta release which isn't a million miles different. At around 35,000 stations its a substantive increase in station numbers over what already exists. It would be interesting to see how it compares in the different ways of slicing and dicing here. Using just our default formatting this seems to show a greater warming trend than GHCNv3 (raw vs. raw - we'll be working on creating a new homogenized GHCNv4 product off the databank once its frozen in first release form in Jan). That difference seems not primarily to be down to sampling new areas of the globe. I aim to write something on that this week if I get the chance.
  33. DIY climate science: The Instrumental Temperature Record
    DOOMDAYS: Are you using the HadSST3 data? That only runs to 2006. The results will get truncated to the shorter running of your land and ocean data. (Hadley are being a bit slow on this one, given that HadCRUT4 is now monthly.) Caerbannog: Thanks for the comments. Your work inspired some of the features. You're also a lot more effective at reaching a diverse audience with your results than me. But there's room for lots more people to join in. We really want instrumental temperature record apps Windows, Mac, Linux, Android and Ipad. Also different methods, like Nick Stokes'. I've got some of the code for my version in python as well as javascript which could be a base for the PC versions.
  34. It's El Niño
    @ skywatcher #180: Excellent summary of why Tisdale's dog will not hunt. Thank you for all that you do.
  35. It's El Niño
    Bob Tisdale #158-163, thanks for at least making an attempt to answer my questions. Unfortunately, despite the verbose nature of your responses, you are still under the mistaken impression that you have a unidirectional energy imbalance driven by ENSO. You appear to conveniently highlight when heat is stored, while neglecting that heat is released during other phases of ENSO. Additionally, you completely avoid providing any sort of an explanation as to why ENSO would have fundamentally changed in the past century. This is, in fact, really important, as without this you are arbitrarily claiming that a unidirectional natural process magically came into being just in time to coincide with large industrial emissions of CO2. Your answer in #162 is almost comically poor, as it makes no attempt to come up with the necessary process or supply any evidence, it just verbosely dodges the question. I understand that the hordes at WUWT are rather easier to please, but it is actually necessary to have a physical mechanism that works beyond the last 30 years of data - as Kevin C has tried to show you. You top it off with some entertaining approaches to greenhouse physics. We observe less heat is escaping to space, at GHG-specific wavelengths (these are the same long-lived greenhouse gases that make Earth habitable), and more longwave radiation is observed to return to the Earth's surface, also at these GHG-specific wavelengths (e.g. Harries et al 2001, Philipona et al 2004 etc). Where is this heat going? You cannot escape this question by implying that the heat vanishes from the system simply beause longwave radiation does not penetrate deeply into the ocean directly! You're implying that all this energy is not accumulating in the Earth system, so it must, logically be escaping somewhere, in your world. Where? We can see it's not going into space. You seem to want to wish away the observed energy gain we see as a result of greenhouse gases (coincidentally what we have expected from a century of radiative physics), and you want to wish into existence a mysterious new unidirectional process causing the oceans to warm because of ENSO. But sadly, your answers are long on words, and short on physical mechanisms, and ultimately disappointing for those of us who want to be able to explain the full body of empirical evidence.
  36. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    And there's also the small matter that a 10 metre sea level rise would not manifest in isolation from other, extremely serious impacts... Oh, and there's the other small matter that if it gets to the stage of a 10 metre increase in sea level, it's not likely going to be stopping there. And if we've pushed the system that far, the final equilibrium point described by those aforementioned other, extremely serious impacts isn't one in which there will exist on Earth anything resembling a Western-style human society. Indeed, if it reached that point there'd likely not exist any society where even printed words and reticulated water supplies were in use.
  37. Weighing change in Antarctica
    Yes, GRACE doesn't help at all for the ice shelves since there is no mass change in the column when a *freely floating* block of ice melts. GRACE could be used to help remove any sea level component from altimetry, but that depends on good snow densification models for the altimetry, as well as a good GIA model for GRACE. And it's a small signal. For now, I think the most useful thing about the ice shelves is that we can use GRACE measurements over them to tell us something about the accuracy of the GIA models near to the regions of grounded ice.
  38. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    climateadj @9: 1) You commented, and I criticized your comment on the cause of the increase in losses due to climate related phenomena. That increase is not adequately explicable in terms of increased population, property values or the locations people choose to live (although they are relevant factors) as is shown by the two graphs I showed. Your pseudo explanation in terms of people living preferentially on the coast was just that, a pseudo explanation. 2 You have changed the subject away from the original point on which you commented, which as a defence of those comments tacitly concedes that my criticism was correct. 3 As proof of your careful thought about these issues, you provide us with the link to a website purporting to show an analogue of the Power Dissipation Index of "northeastern land falling tropical storms". Your analogue of PDI is just the wind speed cubed. The actual PDI is the maximum sustained wind speed cubed integrated over time. Hurricane Sandy lasted three times the duration of the two Hurricanes in 1869 that dominate your list. The actual power dissipated by a Hurricane (PD, as opposed to PDI) is also integrated over area. Hurricane Sandy was the largest Hurricane by diameter ever measured, with a diameter of 1,800 km. The two hurricanes you note in 1869 where quite small, with one being only 97 km in diameter at landfall, and the other not significantly affecting Massachusetts though it made landfall in Maine. That suggests Hurricane Sandy dissipated somewhere in the order of 50 times the power dissipated by those two storms combined. Your "index", however, would not show this; and does not even include Sandy on the list. I should note that the size of Sandy alone shows it to not be the old normal. Whether it is a new normal remains to be seen. Consequently, while evidence of a willingness to do some calculation, your site hardly constitutes proper analysis. To your credit, the work you have produces might well be the sort of graph that would appear on Roger Pielke Jnr's site, but is not the sort of work I would expect from a professional. 4 The most interesting feature of your site was the list of North East landing tropical storms. It shows that about 10% of such storms arrived as late in the year as, or later than Hurricane Sandy. The latest landfall was November 28th, 1888. It is not apparent that any of the approx 10 late land falling tropical storms hybridized with a cold front thus forming a "frankenstorm", although certainly they had the potential to do so. Ergo the lateness of Sandy in no way suggests that this is a new normal. 5 Nobody speaking though fully would suggest that global warming "caused" Hurricane Sandy. There are too many factors involved, most of them meteorological rather than climatological, in the formation and development of a Hurricane. But increased Sea Surface Temperatures are positively correlated with Hurricane power (PDI), and increased sea levels will increase the final depth of storm surge. It follows that global warming has contributed both to the destructive force and the magnitude of the storm surge of Sandy. Without global warming, an equivalent storm would have been less damaging. Whether Hurricanes of such large diameter could have existed without global warming is another matter. As it happens, none with a diameter greater than 750 miles has been recorded prior to 1996, although that may just be a matter of the inability to record storm diameter prior to reliable flight.
  39. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    climateadj, You don't seem to realize that you are missing at least one key issue here. Namely, that the "cold" unequivocal fact that weather systems today are developing in what has become the new norm, a warmer and more moist troposphere. It is this more energetic setting that is a cause for great concern, an apt analogy is weather on steroids. Trenberth (2012) spoke to this very issue, "All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be." What is more, this new norm includes higher ocean temperatures and higher sea levels that further compound the issue. Think of cumulative effects. To deny that storms are now developing in a new norm, or that this won't have consequences, one has to deny that the atmosphere and oceans are warming, that (consistent with the Clausius-Clapeyron relationship) the atmospheric water vapour content is increasing and that ocean levels are rising.
  40. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    It is noteworthy that currently it is very difficult to actually measure fracking contributions to methane and/or leaked natural gas. Several attempted studies in my old stomping grounds (Pennsylvania and New York states) have been quashed or unfunded due to industry and local resistance to on-site measurements. "Drive-by" measures show methane levels more than 3x regional averages - but on-site counts are simply not available.
  41. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    michael sweet - "Sea ice" has 21 hits on Curry's publications (from that online list). Most of those articles are pre-2005, but include the like of Liu, Curry and Hu, 2004: Recent Arctic sea ice variability: connections to the Arctic Oscillation and the ENSO, and among others Holland and Curry, 1999: The role of different physical process in determining the interdecadal variability of Arctic sea ice. I believe such articles are relevant to Curry's knowledge - a decade will have some impact on currency, but not on familiarity with the basics of the field. As is (more recently) Dr. Curry's emphasis on "uncertainty monsters", if only by very puzzling contrast.
  42. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    This is the old "more stuff in the way" argument. There are a variety of metrics you can use to measure this and Tom has pointed out a couple. There are lots more and if anybody would have a real interest in figuring it out, the global insurance industry certainly does. Google Munich RE for what a big reinsurance company thinks.
  43. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    Agnostic, I acknowledge that the issue of fugitive emissions from shale-gas operations is not yet settled and that in some instances there may well be significant gas leaks. As far as I can tell, contra to your link, the apparently leaky gas fields in Queensland are coal-bed methane fields, which are typically shallower than shale gas fields and are not artificially fracked. Not that the climate system cares where the methane comes from... One source of GHG emissions from some shale-gas operations that is incontrovertible is the deliberate venting of carbon dioxide from some fields after it has been separated out from the produced methane to make it saleable. For example, in some shale-gas fields in British Columbia, the produced gas contains 11% CO2. It would be relatively cheap to sequester this gas (much of the cost of CCS is the separation cost, which is already sunk in this case), but this has not been mandated by the provincial government.
  44. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Further to Magnus and Tom, maybe as so often is the case "it depends," in this case on what we mean by "our society." If you live in Norway it's reasonable to suppose 10m would not effectively collapse society. For Bangladesh a different story; most of Bangladesh is below 10m, with the capital Dhaka at 4m. It's hard to imagine most of the ~150M population of Bangladesh making a move to the <20% of the country left dry by a 10m rise in sea level and in any case they'd be confronted with the problem of what to eat after virtually their entire inventory of arable land was lost. There are a number of other countries in the world that live in a similar "deltaic mode."
  45. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    Tom Curtis @6 "Or perhaps there just are some people who will say anything to avoid actually thinking about the data." Actually, I've thought about the data, closely: https://sites.google.com/site/climateadj/home/noreast-pdi There's no evidence that Sandy like storms are the new normal. We are in a period of high activity which is the old normal. God forbid if the 1869 hurricane season repeated itself, with the storm tracks a couple of hundred miles south. There's a name for people who refuse to look dispassionately at the data. It starts with an "a".
  46. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    I should note, with regard to Magnus claims (@4), even a 10 meter sea level rise would not, by itself, be enough to cause the collapse of our society, or even significantly impoverish us. In particular regions, sea level rise is likely to be devastating in terms of lives lost and financial costs, but primarily by worsening the impacts of storm surges. A very small percentage of the total land surface will be lost to inundation. Consequently, except in low lying deltas, the cost of adaption will be met simply by moving major cities about a kilometer inland - something certainly within our economic ability.
  47. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    chriskoz @8, I think you are completely correct on this. A 5 meter sea level rise per century would be equivalent to melting a third of the combined West Antarctic Ice Sheet (WAIS) and the Greenland Ice Sheet (GIS) within a 100 years, which is IMO not credible. Hansens formula of 1 mm of sea level rise in 2005-2015, doubling every ten years results in the complete melting of all ice sheets by 2175, a 70+ meter sea level rise in under two centuries. Plainly the doubling time (if it exists at all) must terminate rather quickly, and is very likely to do so at, or less than, the Heinrich event rate. Being fair to Hansen, his point appears to be, not that sea levels will rise by five meters in this century, but that far more rapid rises than is allowed for by linear increases are possible, so that the likely rise is significantly above linear projections. He may be right in that. I would not exclude a two meter rise, although I believe the 1 to 1.2 meter range to be far more plausible.
  48. Past 150,000 Years of Sea Level History Suggests High Rates of Future Sea Level Rise
    Thanks DB for the link to Hansen 2012. The claim therein, of exponential, 7y doubling, IS desintegration is from the curve fitting to GRACE data, as seen on its Figures 8a-d. With such curve fitting, it finds the SLR as high as 5m by 2100 possible. I find the practice of such curve fitting questionable. Especially, if it arives at the improbable conclusion of dSLR 50mky-1 (5mcentury-1), not seen in last 1500ky, far in excess of Heinrich events. On top of that, it must be remembered that strong negative feedbacks on melting rates do exists, like ice flow rates and cooling of the upper ocean. And there is simply not enough ice (far less than the emount of Laurentide IS than triggered Heinrich events) to sustain the exponential rate. So Rahmstorf 2007, being a conservative, semi-empirical linear model, concluding 1m SLR in 2100 is more realistic.
  49. Newest Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
    Michael, a term search for "Arctic" on her publications list turns up 54 hits. Those hits will include the 2 hits for "Antarctic". Clearly the majority of her polar related research has been related to the Arctic rather than the Antarctic. A search for "Ice" turns up 49 hits. I gather she has researched the meteorology of the Arctic, including ice formation in clouds more so than sea ice extent. "Sea ice" returns only 21 hits.
  50. Subcap Methane Feedbacks. Part 2: Quantifying fossil methane seepage in Alaska and the Arctic
    Doug H A number of Papers have been published recently on fugitive emissions of natural gas, variously estimating them at between 2%-5% of total production. There are indications in Australia that fracking may result in much higher emissions, though it is unclear if these are from the ground above the fracked area or the well head area. Andy S notes that … leakage and other environmental consequences of fracking have been exaggerated … However, preliminary (non peer reviewed) research undertaken by the Southern Cross University in Queensland indicates that methane concentration in the atmosphere above areas where fracking gas mining has occurred are around 3 times higher than the global average. http://www.istockanalyst.com/business/news/6155419/fracking-blamed-for-methane-releases As pointed out by scaddenp significant venting of methane also occurs during coal mining. With introduction of the carbon tax, it is expected that several of the most “gaseous” mines in Australia will find it is no longer economic to continue operating and will close.

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