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Comments 64101 to 64150:

64101. Bernard J. at 17:50 PM on 12 February 2012
       The Year After McLean - A Review of 2011 Global Temperatures
       And Doug H, I feel your pain. Often even the simplest answers appear to be so only in hindsight, and the answers to those questions above don't immediately jump out for many people - sometimes even for people are supposed to understand statistics! Of course, the whole underlying issue completely sails over the heads of the Denialati, no matter how many times it's explained to them - and it's been explained to them repeatedly. When Bolt commented on the Santer et al paper he thought that it meant that because it required 17 years of data to detect statistically significant warming rather than 10 years (according to the paper of Santer et al), it meant that scientists wouldn't know until 2018 (2011 + 7 more years) if the planet was warming. That's either very stupid mind, or a very ignorant mind, or a very mendacious one - or some permutation of any or all of the preceding. And Girma Orssengo certainly didn't ever figure it out - if you read the Matthew England thread you'll see that his answer, when it eventually came, is completely and utterly clueless.
64102. Bernard J. at 17:15 PM on 12 February 2012
       The Year After McLean - A Review of 2011 Global Temperatures
       Doug H. There are simple ways and there are more complicated ways to derive answers to those questions. KR has already directed you to Santer's et al work, and Foster and Rahmstorf consider the problem too. There's an abridged version of the latter at Open Mind, but remember that this analysis removed the influence of exogenous factors such as ENSO, where Santer et al didn't. Thus, Santer's minimum-required time period for statistical significance is a little longer.
64103. owl905 at 16:50 PM on 12 February 2012
       A prelude to the Arctic melting season
       From Camburn #17: "1. There seems to be a solar influence concerning Arctic Ice flucuations." The opposite - ice-extent reductions have increased sharply in a period that the pro-pollutionists raved and ranted was dominated by low solar activity. "2. Black Carbon, an anthorgenoponic emission, is also responsable for the current decline in ice." Sure, ABC shows up for a serious influence in this decade - that's the current picture. But the Warsaw Pact Cloud didn't have the same effect in the 70s/80s. And the clear decade of the 90s didn't produce a recovery. "3. Increased temperature is also responsable for the decline in Arctic Ice." Very true, except for the weak phrase "is also". The places to start with understanding the disruption of the Arctic ecosystem is heat conveyers - through the winds, via ocean currents north, and from freshwater runoff into the Arctic Ocean. As for the St. Roch reference - it is anecdotal. There's no metric, no baseline comparison ... it's just an amusing arctic-summer observation.
64104. Tom Curtis at 16:17 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       Norman @39, you say I provided a good challenge, and then you do not take it up. The challenge was to show both global figures for groundwater recharge and withdrawals. You point to a paper which provides both of those figures, but you only discuss the differential in basins in which withdrawal exceeds recharge. For what it is worth, the paper you link to estimates a global recharge rate of 15,200 km^3 per annum, and a withdrawal (abstraction) rate of 734 km^3 per annum. So withdrawal is only 5% of recharge globally, according to this paper. So, despite your continued cherry picking of the data, you have still not shown evidence that supports your claims, let alone establishes them. If you wish to discuss the depletion rates of aquifers used for irrigation, than regional data confined to those parts of the Earth suffering from depletion is relevant, but your entire discussion is then off topic in this thread. If we want to discuss the effect of the global water balance for aquifers on sea levels, then discuss the global effects, and stop this transparent cherry picking. Finally, I notice that you have neither explained nor apologized for your blatant cherry picking as detailed at 34 above. In view of this there is no point in further conversation with you until you do. Somebody capable of unapologetic cherry picking in so blatant a manner is not interested in rational conversation, or in finding the truth of things. They are only interested in deceiving people with half truths. Such people should be exposed, not debated with, and your continued cherry picking has certainly exposed your intentions.
64105. Rob Painting at 15:58 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       Agnostic - in regard to the Asian High Mountains - 2010-2011 saw hundreds of billions of tons extra snowfall. If the study had not included those years it would have shown a dramatic loss of ice. What it shows is that, rather than being stable, as erroneously reported elsewhere, even the high plateau is warm enough to sheds lots of ice annually. Are they likely to get such snowfalls in the future? There are decades of warming yet to come, how will that affect the region?
64106. Riduna at 15:46 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       GRACE provides a good indication of the magnitude and area of ice loss but, because it has difficulty in detecting smaller areas where loss is occurring, it should be regarded as providing an understatement of land ice loss. For example, physical inspection shows that glaciers of the Sierra Nevada are in retreat. Similarly glaciers in Glacier National Park are mostly in retreat, yet neither of these is detected by GRACE - or are they detected but the data is not used to show these losses? The reason I ask is because 2009 data provided by GRACE did show depletion of groundwater in the Central Valley of California over a 6 year period but now it purportedly shows nothing – or at least nothing it reported in respect of this area. Nor is anything reported on the state of glaciers in the numerous Russian mountain ranges, thought many are known to be in retreat. GRACE detects gravity changes arising from the movement of water whether in the form of ice, snow or liquid. If glacier ice melts in the Himalaya mountains and is stored as natural lakes, then GRACE will show no loss since there has been no change in gravity. GRACE can not measure the different forms water is present in an area, only the extent to which it has moved into or out of that area. Rob Painting makes the valid point that … “under conditions, such as the recent La Nina-dominant period … a much warmer western tropical Pacific intensifies the Asian Monsoon, and dumps more snow on the high plateau.” This does not appear to have occurred during the reporting period, though it may have occurred more recently. Had it done so, GRACE would have recorded the resulting change in gravity – unless of course increased precipitation was largely balanced by loss of water from the region. What is clear is that if GRACE shows net loss of 500 gigatonnes/annum, there is only one place most of it has gone – the oceans. It puts me in mind of James Hansens prediction of decadal doubling in the rate land ice loss throughout this century. Anyone who thinks that will have no effect on RSL needs to give cogent reasons for their thinking.
64107. Rob Painting at 15:39 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       layzej @87 - Well, I'll just stick to the CO2 fertilization effect, and ignore all that utterly dire stuff about ocean acidification then. First up let's be clear, the argument that John Nielsen-Gammon makes is that extra CO2 will be beneficial in the next few decades. To test that we need to look at what the observations reveal. Again, I point out that we (SkS) don't dispute that CO2 fertilization is a real phenomenon, but the point is, will this effect be enough to counter the negative effects of a warmer and perhaps drier (for many regions) world? We know that the carbon cycle models used in the last IPCC assessment report expect this CO2 fertilization effect to be huge in the 21st century. Those models simulate a dramatic draw-down of atmospheric CO2 by land vegetation. But they also assume no nutrient limitation - which seems a glaring omission. - no evidence of CO2 fertilization leading to increased biomass in a Thai tropical forest: - Long-term increases in intrinsic water-use efficiency do not lead to increased stem growth in a tropical monsoon forest in western Thailand - Nock (2011) - no CO2 fertilization net benefit in a Costa Rican rainforest - Annual wood production in a tropical rain forest in NE Costa Rica linked to climatic variation but not to increasing CO2 - Clark (2010) - no CO2 fertilization net benefit in a Canadian forest - Testing for a CO2 fertilization effect on growth of Canadian boreal forests - Girardin (2011) - and crucially, no global CO2 fertilization effect net benefit in the last 40 years - increased water-use efficiency during the 20th century did not translate into enhanced tree growth - Peñuelas (2011) they write: "Location A global range of sites covering all major forest biome types. Main conclusions These results show that despite an increase in atmospheric CO2 concentrations of over 50 p.p.m. and a 20.5% increase in iWUE (intrinsic water-use efficiency) during the last 40 years, tree growth has not increased as expected, suggesting that other factors have overridden the potential growth benefits of a CO2-rich world in many sites. Such factors could include climate change (particularly drought), nutrient limitation and/or physiological long-term acclimation to elevated CO2. Hence, the rate of biomass carbon sequestration in tropical, arid, mediterranean, wet temperate and boreal ecosystems may not increase with increasing atmospheric CO2 concentrations as is often implied by biospheric models and short-term elevated CO2 experiments." And the real clincher is that the tropical regions, despite the huge deforestation occurring there, are actually by far the largest land-based carbon sink, and they happen to be the most threatened, because tropical trees most likely exist near a thermal tolerance threshold. This meme by John NG is extremely disappointing coming from a climate scientist who should know better. But to adequately de-bunk it (yes, there is a great deal more peer-reviewed science to debunk it) requires perhaps a two or three-part blog post/rebuttal. I've added it to my to-do list.
64108. Jose_X at 15:29 PM on 12 February 2012
       Monckton Myth #17: Debate vs. Denniss, Part 1
       ..quickly, let me apologize for the grammatical and spelling mistakes in the earlier comments. I think one can make out what I intended to say, but they are a bit annoying to read. Also, the part contrasting measurement+observations against just modeling was way drawn out and a little inconsistent as worded. ..Whatever.
64109. Camburn at 15:20 PM on 12 February 2012
       Climate change policy: Oil's tipping point has passed
       Sphaerica@68: I don't know why anyone needs to drive a tank for mundane tasks. And I sure don't know why anyone would drive to get one loaf of bread. I also have a hard time with that....as we make our own bread, have our own garden, etc. 2. I am very concerned with ocean PH. I think that is the largest downside risk to higher levels of CO2. That is also the most demonstrateable risk....it just can't be ignored. 3. Temperature records are a very poor metric to use concerning climate. A desert can have a temp of 110F and have less heat content of the air than a Mississippi swamp at 75F and 90%SH. I have always maintained...forget temperature, it doesn't demonstrate anything. Even the "Texas Heatwave" of last year had less heat content than the normal climate there because the air was dry. 4. Mediation: a. I have been a staunch supporter of nuclear for over 30 years. I find it senseless that we have NOT invested and directed investment to this precious resource. b. Solar is great where practical and competitive. In North Dakota, USA, it will never work. c. North Dakota has wind. However, there are drawbacks to wind which I am learning. I live approx 14 miles from an approx 180MEG wind farm. Through my co-op, I own part of it. It is not working out very well, unfortunately. And when the geese get done flying through it, makes me sick......so I have become not too keen on wind anymore. I don't think anyone denies climate change, as the evidence of climate change is certain. Where you will find the arguement is the sensativity of climate to CO2, and that is very debateable. You will also see folks deny the effects of the sun who are ardent AGW supporters. That should never happen, but I read it all the time. There is too much literature out there showing hydrological effects from sun variations over wide drainage areas. This gets back to clouds and sun. There is an established relationship there that can not be denied as it is evident in drainage basin studies. From a moral perspective, FF should be saved as much as possible. Plastics, high HP needs etc are well met by FF. They really do enhance our lives. How do we achieve reductions in FF use? 1. Educate people without the constant "fear" factor. 2. Stop government meddling. Remember, the light bulb, the telephone, so many things that we use daily were invented by private industry. That industry did not have to worry about a government funded institution owning the pattent. 3. Get fed/state/local spending under control so that people, at least in the USA, have the resources to make "smart" decissions. The current projections show that an economic breakdown is only a few years away, which will completely hault an orderly transition. Just a few ideas. Moderator: I looked for a different thread as this has moved a bit off topic and didn't find one. I don't want to get banned again as I feel I have a perspective to offer this forum that at times I feel it lacks. Please delete my note to you before allowing this to be posted or delete the post at our discretion. Thank you.
64110. Tom Curtis at 14:57 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Layzej @80, the time frame considered in the response is just the next century, and as such is determined by "skeptical argument" it is rebutting. Where the so-called skeptics nuanced enough to argue that in the sort term, net benefit to agriculture from global warming is positive, but in the medium term it is uncertain, and in the long term under BAU it will be significantly negative in most areas, and negative overall globally, I'm sure the response would have discussed the different effects over different time periods - and largely agreed with them. I'll also note that had the myth it is rebutting been more geographically nuance, I'm sure some of the geographical nuances would also been reported. One of those is the fact Camburn is benefiting from, ie, that the Northern USA and Canada will probably get higher yields for some time to come (possibly for the next century even with BAU). Unfortunately their good fortune in that respect does not generalize to the rest of the world.
64111. Philippe Chantreau at 14:56 PM on 12 February 2012
       A prelude to the Arctic melting season
       Camburn, B.S. Anecdote, per Webster dictionary: "a short account of an interesting, often biographical incident." Any biographical incident has little bearing to the bigger picture. It is an individual occurrence. The St Roch's account is no more telling than the swim over the pole. How long did it take to cross the Northwest passage back in these days? 3 years. Recently, it was done by a small sailboat in a few weeks. This argument is so ridiculous I don't know why anyone would even put it forth. As much as 40% due to black carbon. That leaves 60% or more (could be much more) to other factors. Gee, I feel so much better knowing that. Looking back at your history here it seems you have no more to say than you ever had before.
64112. Bob Lacatena at 14:42 PM on 12 February 2012
       Climate change policy: Oil's tipping point has passed
       67, Camburn, Then with limited fossil fuel resources that is all the more reason to preserve those reserves for the situations where it is difficult to find other power sources (e.g. high HP and jet fuel). So why do we squander it by driving SUV's with one person in them to the store to buy one loaf of bread? Why do we use fossil fuel to generate electricity for light and power in homes and buildings? Why does our entire power infrastructure revolve around fossil fuels with no visible effort to make the necessary transition? We have three hugely compelling reasons to stop this: 1) FF are a limited resource which will cause economic upheaval when they begin to run short (and many say that time has arrived, as the above post explains). 2) FF are generating greenhouse gases which will inevitably cause economic, behavioral and physical harm, for which the only solution will come from a new, viable power source that not only replaces fossil fuels but also would provide the accompanying energy that will be required to adapt to climate change. 3) FF are dramatically changing the pH of the oceans, which will result in a lack of food availability in the greatest farm this planet knows (the oceans)... and the chances of finding a viable solution to that growing problem, no matter what power source is discovered, is virtually zero, so every day's delay is another step towards disaster. So why do people continue to find every reason they can to deny climate change, ocean acidification, and the inevitable economic downside of a fossil fuel economy, when a three-barreled gun is staring us in the face?
64113. KR at 14:36 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       Norman - There are two separate conversations going on here, and a certain lack of recognition of that issue. First: Deep aquifers are being depleted at high rates in many ares. This is definitely bad - leading to numerous agricultural issues and relocation costs. Current practices will not be sustainable in many areas. But the best data available indicates that a roughly equivalent amount of water is being sequestered elsewhere, changing the current availability of said water in considerable detail without affecting total runoff. While I don't want to minimize this very important issue, it's not the center of this thread. This thread is on the climate change effects on the cryosphere, on ice melt in areas >100km^2 as measured by GRACE. It is very useful, however, that the GRACE data also supplies some information about aquifer changes. Second: Sea level rise due to anthropogenic is not greatly affected by terrestrial/anthropogenic usage. Milly et al 2010 shows that in considerable detail (with numerous reference of their own). --- So: Aquifer level changes, recharge rates, etc. - all of those are off topic here. Assertions that anthro water usage affect sea level are not supported by the full set of data, your cherry-picking of single numbers from Milly 2010 notwithstanding. Moderators - Perhaps side topics such as aquifer changes need to go elsewhere?
64114. Philippe Chantreau at 14:34 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Camburn, "it is established" requires real substantiation, put up the references. This statement leaves a lot to be desired: "By having larger root balls/mass the plant has a larger structure to overcome normal potential weather variations." Provide references to studies showing that it actually does allow them to overcome. Without it, this is nothing but wishful thinking. When they were trying to break the sound barrier, engineers though that a generously reinforced structure would enable a onventional airplane to go there and back safely. It wasn't quite so. If you're so worried about going broke you need to adress the factors that make prices so volatile. They belong with the banks and the speculators trying to profit from commodities markets, good luck going after that. I live in the 40's latitudes too and I was battling mosquitoes on my outing to the falls today with the kids. Never seen them yet in this place at this time of the year. If you are in a place that already was on a Northern margin, then probably you're safe, and warmth in your area is indeed beneficial. I'm sure the ones who live closer to the Southern margin have a different take. Of course, if we stick purely to the capitalistic risk/benefit analysis, in your individual case you're not supposed to personally give a dam* about the problems of farmers who live in other places. In fact, the more they suffer, the better you're likely to make out: production decreased on their part, increased on yours, if the overall production is down, you'll really make a killing without having to do anything special. More power to you I guess.
64115. Camburn at 14:32 PM on 12 February 2012
       A prelude to the Arctic melting season
       As presented above: 1. There seems to be a solar influence concerning Arctic Ice flucuations. 2. Black Carbon, an anthorgenoponic emission, is also responsable for the current decline in ice. 3. Increased temperature is also responsable for the decline in Arctic Ice. The loss of Arctic Ice is a multifaceted issue.
64116. Norman at 14:30 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       KR and Tom Curtis Here is another report which gives even a higher figure for unsustainable water use (being withdrawn at higher rates than replenished meaning it will increase the surface amount by that volume since it is no longer present in the location it had been). Fresh Water Chapter 7. In this book you can scroll down to page 175 and view Table 7.4 In this table they give the World non-sustainable water use. Ranges from 391-830 km^3/year (Note Tom Curtis, even replenishable aquifiers can be pumped at rates exceeding their recharge rates). If you use the highest value for non-sustainable water use it would be a very significant player in SLR. (830/61=13.6)....(13.6 x 0.17 mm SLR for 61 km^3 H2O=2.31 mm). Current SLR rate is 3.4 mm/year so this water use could account for over 50% of the current rate of SLR if the higher figure is used. I am not saying this would be valid. I brought it up to make a point that you should not discount water mining as one possible source of SLR, it may be larger than you currently accept.
64117. Camburn at 14:30 PM on 12 February 2012
       A prelude to the Arctic melting season
       Philippe: The observation from the Captains log are not anecdotal. They are reported observations. Observations are 1st hand, anecdotal are 2nd hand. The following paper from DMI is worthy of consideration to explore all avenues that affect Arctic Ice. It has been established that "Black Carbon" may be responsable for 40% of the current temp/melt. Ref link to Schmidt/Shindell posted above. DMI East Greenland Ice
64118. Camburn at 14:17 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       Norman@41: AT the rate of depletion of fixed aquifiers, the problem will come to an end in approx 18 years based on the latest information I read. Not a very comforting thought at all.
64119. Norman at 14:14 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       KR @35 Your link does state that ground water mining will result in a positive increase in SLR of 0.25 mm/year. My problem is with the huge difference in calculating the amount of unsustainable water removal from deep aquifiers. The listed total amount of deep water used in irrigation is 545 km^3 per year. As Tom Curtis pointed out, this amount does not indicate a recharge rate of even the deep water wells. I did find another source that points out that of this amount above, 234 km^3 (in the year 2000) is unsustainable meaning it is not going back into the deep aquafier storage but being removed and added to the total surface water amount. Section 8.4.3 in your linked article are what I question. How are their numbers so much lower than other sited sources? If you use the other value of 234 km^3(which was a 2000 number and may be higher today with expansion of deep water mining) instead of 61 km^3/year that your link uses, the amount of SLR due to deep water mining of fossil aquifiers is closer to 1/5 of the total amount and is a valid player in the SLR equation.
64120. Camburn at 14:14 PM on 12 February 2012
       Climate change policy: Oil's tipping point has passed
       Sphaerica: I was talking about large HP needs. When it comes to cars, I am 100% behind you. I have a couple of friends that have a hybrid. Yes, in winter they don't work too well, but for 70% of the year, they work very well. My next car purchase will be a hybrid. I have a hard time understanding why anyone wouldn't buy a hybrid for transportation needs of a few people. And the costs are not high in comparison to many alternatives. The practicality when it comes to large HP needs tho is that many times the large HP needs don't shut off for days and pontentially weeks at a time. There is no time to recharge, and the price of having batteries large enough to supply the power over extended periods of time just does not compute.
64121. Philippe Chantreau at 14:11 PM on 12 February 2012
       A prelude to the Arctic melting season
       Camburn, how am I supposed to be impressed in any way by a record reporting no ice in sight in late August and September? In the anecdotal area, do you remember about the guy who was swimming in open water at the North pole a couple of years ago? Shall we put this up in the anecdote contest? Please... This anectodal record is of very little interest. This winter ice area and extent are low so far. We'll see how it turns out in late September, which is the metric that matters the most. I note that the January extent is so exactly on the linear regression of the overall decline of the month' extent that it's almost as if the ice had been rehearsing. I find the ice area graph at Cryosphere today even more concerning, it's showing the same pattern as last year, but 250k sq. Km lower. In any case, we're nowhere near the 1979-2000 average, in either metric.
64122. Camburn at 14:02 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Sphaerica@86: 1. It is established that cereal plants respond well to increased CO2. 2. It has also been established by root studies that plants develop larger root mass with the presence of CO2. 3. By having larger root balls/mass the plant has a larger structure to overcome normal potential weather variations. 4. You indicate more volatile precip and temperature patterns. I don't know if you can get much more volatile than the climate I live in. An old saying in the upper plains of the USA is "If you don't like the weather right now, wait 5 mins and it will change." The higher levels of CO2 that increase plant mass that I have read are up to approx 850ppmv. What happens after that, I don't know. The studies done by the Ag community reflect the potential levels that "may" be obtained. The element of risk in production ag is so large, that a small addition of a potential benifit is viewed positively. The upper plains of the USA, and I live very near the 49th parallal. One of the areas that is suppose to be most affected by climate change. At this point and time, there has not been any variation from the long term norms of just right, to too wet, to too dry. From too cold, frost in 2005 in August, to to warm.....that hasn't happened since 1988. I read studies of anything pertaining to production ag with a very critical mind. A small change can be the difference between being profitable, and going broke. And worst of all, not having a crop, as my desire is to feed people. Warmth in my area is benificial to production as most of the time we are on the edge of being too cold. Precip patterns are within the boundaries of a 80 year wet/dry cycle in the Central Corridor of the USA that is part of a longer 400 year cycle: 400 year cycle of precipitation of Great Plains of NA Shorter cycle within the longer cycle:
64123. David Lewis at 13:52 PM on 12 February 2012
       Global Sea Level Rise: Pothole To Speed Bump?
       Hansen, in a 2005 editorial essay cited Kienast et.al.2003 and said "In melt-water pulse 1A... sea level rose about 20m in approximately 400 years" which "is an average of 1m of sea level rise every 20 years". Which is about 0.14 mm per day. This would be a catastrophic rate for people living near the sea. He noted that the ice sheets disintegrating at the time "were at lower latitudes than the ice that remains today and the period of rapid ice sheet disintegration was undoubtedly preceded by a period in which the ice was preconditioned for collapse". But, he points out climate forcing today far exceeds the forcing that drove melt-water pulse 1A. And, he said, sea level rise doesn't have to add up to 20 m to obligate scientists who expect it to happen to warn that an event anything like it would "wreak havoc" on civilization. Hansen has said in the past that if the planetary energy imbalance is about 1 W/m2 and all that energy was going into melting ice it would raise sea level by about 1 m per decade. Obviously, an armada of icebergs shooting off Antarctica wouldn't have to melt to raise sea level. Pfeffer told a story at the AGU this year about how the sea level rise threat isn't being fully grasped even by those he would have thought must be exposed enough to the data to get it. He said MOMA in NYC exhibited a model showing a New York that by 2100 had protected itself from 2m of sea level rise. He asked the designers, what was the plan for the ongoing steady or possibly accelerating rise after that - how was their design going to cope with another meter and another one after that? Blank stare.
64124. layzej at 13:47 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       muoncounter @77, Fact 1 and 2 are off topic on this thread and moreover not areas where JNG has suggested that SkS has fallen down. Michael sweet @78, I'm not sure what you are getting at. The JNG post was written after considering this very SkS post and finding it wanting. Rob @79, No doubt there are many reasons to reduce CO2, however JNG has suggested that this particular item is a litmus test to determine whether the person you are listening to is honest and knowledgeable. A bold statement and one that I am grateful to see addressed by you and the S(k!)S team. Tom Curtis @80, thanks for the thoughtful and thorough response! Your points are all well taken, although I'm not sure it's a good idea to consider policy turn around time when writing a post. I would like to think of SkS as a place that cuts through all the BS and provides the facts - warts and all.
       Moderator Response: [JH] The auditions for SkS Moderator candidates were held last week.
64125. Norman at 13:45 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       
64126. Norman at 13:44 PM on 12 February 2012
       NASA Mission Takes Stock of Earth's Melting Land Ice
       Tom @34 You provide a good challenge "Note that I do not know the recharge rates. Globally they may also be trivial. But you need to either cite them to establish that, or to cite a peer reviewed source to that effect." I did some research into this and found this Nonsustainable grounwater sustaining irrigation: a global assessment. I did sight the 545 km^3 from deep water mining from the other link. I have not found a correct current amount of nonsustainable water mining (fossil aquifiers) so I am not sure what it is in 2012. In 2000 it was found to be 234 km^3 (from the link above). From the abstract: "Results also show that globally, this contribution more than tripled from 75 to 234 km3 yr−1 over the period 1960–2000." Nonsustainable water mining tripled from 1960 to 2000. In 2000 it was estimated to be 234 km^3/year. In 2012 if may be higher than 2000 but probably not as high as the 545 km^3 given in the other article. Nonsustainable means the this water is being removed and not replenished. Here is the general description of aquifier types: "There are two types of aquifers: replenishable and nonreplenishable (or fossil) aquifers. Most of the aquifers in India and the shallow aquifer under the North China Plain are replenishable. When these are depleted, the maximum rate of pumping is automatically reduced to the rate of recharge. For fossil aquifers—such as the vast U.S. Ogallala aquifer, the deep aquifer under the North China Plain, or the Saudi aquifer—depletion brings pumping to an end. Farmers who lose their irrigation water have the option of returning to lower-yield dryland farming if rainfall permits. In more arid regions, however, such as in the southwestern United States or the Middle East, the loss of irrigation water means the end of agriculture." source. Here is another describing fossil water water 75,000 years old in Libyan aquifier.
64127. muoncounter at 13:44 PM on 12 February 2012
       A prelude to the Arctic melting season
       skywatch#9: Polyak 2010 was discussed here. analysis of several hundred indicators of past Arctic sea ice extent tells us that recent losses appear to have no parallel in records going back many thousands of years (Polyak et al).
64128. Bob Lacatena at 13:42 PM on 12 February 2012
       Climate change policy: Oil's tipping point has passed
       60, Camburn,

       Note the "at present there are no economic alternatives."

       Bullsh*t. There are no "economic alternatives" because we continue to invest more and more in the existing infrastructure and comparatively ignore other "uneconomical" potentialities. We keep things that way with our behaviors. Hybrid cars have been feasible and economical for a decade. Only the lack of true massive-scale production keeps their costs high. Our dependence on a rickety and failing fossil fuel infrastructure is primarily hampered by our continued investment in that same, dead-end infrastructure. The denial crowd has done a wonderful job of keeping the lack of "economic alternatives" a reality, and on our current course they will continue to do so for several decades until (as you say) the necessary transition comes with a cultural and economic shock. It stuns me that you are unable to see this or, despite your own admission of the problem, to use your foresight to move past it.
64129. Bob Lacatena at 13:35 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       85, Camburn,

       The types of plants that feed the world have repeatedly demonstrated increased productivity from higher levels of CO2.

       Do they similarly react well to increased temperatures, increased or decreased moisture, and more volatile precipitation and temperature patterns? Do they demonstrate an unending improvement for higher and higher levels of CO₂, without limit or eventual negative result? Are you in a business where you can afford to simplistically look at and focus on a single variable, with complete disregard for other factors?
64130. Camburn at 13:32 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Tom@83: I am in production agriculture Tom. The "quarter" I am most interested in is feeding people. As most of the worlds food stocks are annual in nature and derived from grasses, the area of research most intersting is the responses to co2, etc. The types of plants that feed the world have repeatedly demonstrated increased productivity from higher levels of CO2. Rob@84: I will have to re-read Lobell (2011). There were problems with that study that a farm paper talked about. When I have time to read it and reference it, I will comment on said link. Thank you for the Link.
64131. KR at 13:30 PM on 12 February 2012
       The Year After McLean - A Review of 2011 Global Temperatures
       Doug H - You might then be interested in the Separating signal and noise in climate warming thread. The answer appears to be a minimum of 17 years for any trend to be statistically identified in the presence of observed climate noise. Others (ahem) might want to read that as well. Decadal trends are just not enough to identify any trend, whether it's plus, minus, or flat.
64132. Tristan at 13:06 PM on 12 February 2012
       Climate change policy: Oil's tipping point has passed
       The first major impact of a significant increase in oil price is probably famine in Africa. I'd suggest that it is non-trivial for Africa to switch from oil-dependent farming.
64133. Camburn at 12:55 PM on 12 February 2012
       Northwest passage has been navigated in the past
       JMurphy: The Voyage of 1944 was not quite as difficult as you maintain. Capt Larsen was a skilled Captain. At times there was heavy ice, at times there was no ice to be seen. To have accomplished this without the benifit of satillite images is really a feat in and off itself.
64134. Rob Painting at 12:54 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Camburn - you are misinterpreting what I wrote. Young forests, which are not nutrient-limited in some other way, can indeed benefit enormously from more CO2. The FACE trials indicate that mature forests don't - there's only so big trees can grow and therefore a limited capacity to soak up CO2. Young forests on the other hand have a large capacity for growth and drawdown of CO2. It makes perfect sense. In the real world, however, many areas are nutrient-limited - phosphorus, nitrogen and especially water. That's perhaps why the CO2 fertilization effect (a global increase in plant biomass due to more CO2) has not been found. All the extra CO2 seems to be going into forest re-growth. This tallies with global estimates of growth in pastural coverage- they have plateaued in recent decades. As far as corn is concerned, that too is under threat see SkS post: Maize harvest to shrink under Global Warming - based on Lobell (2011)
64135. Tom Curtis at 12:48 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Camburn @82, I know you enjoy looking at a very carefully selected quarter of the picture. Just don't expect us to be mislead by your propensity. In other words, read the main post. If you can't rebut the points it raises, you have nothing worth saying.
64136. Camburn at 12:46 PM on 12 February 2012
       A prelude to the Arctic melting season
       JMurphy: I did not suggest that the voyage was benign. I am showing what was in the log. They also encountered a lot of ice in places. The point I was trying to establish is: resolution. I will read your link forthwith. Thank you.
64137. Camburn at 12:43 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Tom@80: Elevated CO2 benifits C3 and C4 structured plants. All cereal grains are grasses, so this study has a very strong relation to wheat/corn/ etc. NASA study on C3 and C4 grasses with elevated levels of CO2 It is also well known that enhanced CO2 promotes larger "root balls". Because of this, the plant is more efficient at using the available nutrients/water in the soil. With enhanced levels of CO2 there are indications that farmers will be able to reduce the N input and achieve the same yield. This would allow 3rd world countries to increase the mass of their food production. From a plant perspective, higher CO2 is good. Most plants evolved when CO2 was higher on earth and have not seemed to have lost that desire. But, even with enhanced bio-mass, the lowered PH of the oceans is a mighty concern that MUST be taken into account in the balance.
64138. JMurphy at 12:39 PM on 12 February 2012
       A prelude to the Arctic melting season
       Camburn, you will find further details about the St. Roch's Northwest Passage voyages, written by myself, on Skeptical Science here. Things were not as benign as you seem to be suggesting.
64139. JMykos at 12:33 PM on 12 February 2012
       Zero Carbon Australia: We can do it
       Sapient. I wouldn't consider Cinas population small. China implemented a one child policy in the cites not rural areas. China recognized their population was going to exceed the resources of their land and did something quite controversial about it. A two child policy from the outset might have been more palatable. Quite the contrary, if china didn't have the one child policy, today under the per capita basis they would be entitled to more of the CO2 budget, they would have been rewarded for their population growth. Shouldn't all countries manage their population level to the food and water and other resources their land can provide? By the same thinking the amount of land would factor into the CO2 budget. Not merely the population number.
64140. Camburn at 12:32 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Rob: There is no question that CO2 enhances plant growth. This is documented in this Wisonsin Study. Tree growth with elevated CO2 As far as temperature, the temperature, at least in the main corn growing areas of the USA would have to elevate by over 4.0C to be a growth hinderance. This would have to occur at precise times as well, as corn is sensative to higher temperatures for approx 2 weeks time in the growing season. Outside of the pollination and early fill window, higher temperatures help with the conversion to starch in the ear and can allow greater kernal depth. This is benificial. However, the lowering of PH of the oceans as a result of higher levels of CO2 is a huge concern. The lower PH benfits some crustaceans, but in my humble opinion, the overall benifits do not outweigh the potential negatives. Woods Hole Study of PH
64141. Tom Curtis at 12:19 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Layzej @76, among the interesting things John N-G writes is:

       "As long as the climate effects are small, they don’t matter much, but to the extent that climate changes faster than plants can move around to keep up with it, climate change will be bad for native plants. Worse, in the tropics, the climate may change into something with no existing analogue on Earth and thus no pre-adapted species ready to move in. Computer models with an interactive biosphere generally agree that incremental increases of CO2 help plants overall, and most say that the global ecosystem will continue to gain biomass through 2100. In other words, the better growing conditions due to more CO2 outweigh adverse conditions due to the changing climate for the foreseeable future. The crossover point, where net global growth is actually inhibited by the combination of CO2 fertilization and resulting climate change, is poretty much the most poorly known number relevant to climate policy. Certainly as the climate changes there are concerns about the extinction of species and the loss of the ability to grow adequate crops in some areas. But in the meantime, as long as one is not concerned about the fate of individual vulnerable species, CO2-induced climate change is a net positive for plant growth. This is true based on the most basic numbers of the man-altered carbon budget."

       By my reading, that is in complete agreement with the more detailed discussion above. His objection to this post seem to come down completely to the absence of a sentence saying that despite these grave concerns, for the future, there will be a short term (20) year benefit for plants in general, although not necessarily for crops. Given the turn around time of climate change policy, and the even longer turn around time for any action to start reducing growth in global temperatures, I do not think pointing out a possible short term benefit is either necessary or helpful. Still less so as it is not certain that that short term benefit exists. As noted by Steve Bloom in comments at John N-G's blog, his method of estimating the benefit to plants is indirect, and necessarily includes aquatic as well as land plants. More generally it potentially shows in increase in plant life, not in human agricultural productivity. It is of scant benefit to us if over the coming decades Net Primary Productivity (ie, the total global growth of plant life) increases if that increase is in the form of algal blooms and weeds. Further, I say talk of a potential increase, as even John N-G mentions a possible mechanism whereby the observations of increased carbon take up are compatible with decrease plant growth, ie, a larger decrease in plant decomposition. Although he dismisses that possibility, a recent study (whose title and authors I can't remember unfortunately) showed that production of oil and coal generating strata peak in periods of high CO2 content. Production of fossil fuels requires the burial of organic carbon without decomposition, so that study suggests that high CO2 content may indeed lead to reduced rates of decomposition, primarily by promoting anoxic conditions in warm waters. It seems to me that John N-G would have done well to read the title above. "If only it were that simple". Because of that complexity, Dawei's conclusion was, "The global increase of CO2 is thus a grand biological experiment, with countless complications that make the net effect of this increase very difficult to predict with any appreciable level of detail." That is, he has neither endorsed claims of benefit or of harm to plants from CO2, but merely drawn attention to some of the many complicating factors. In the end, difference between his and SkS's discussion of the topic is that we did not rush to a simplistic conclusion.
64142. Camburn at 12:16 PM on 12 February 2012
       A prelude to the Arctic melting season
       The paper presented is worth getting a copy from the local library: Bowhead Whale Historical Range in the Canadian Archipelago What this provides is evidence of Hisotrical Arctic Ice extent. One can then look at historical climatic patterns during the times of limited ice extent to understand what may lie ahead for our planet.
64143. Camburn at 12:07 PM on 12 February 2012
       A prelude to the Arctic melting season
       Tom@8: Ice loss is a regional item in the Arctic. On the whole, there has been ice loss on an annual basis. I am not confident that there are aduequate records of ice extent prior to satillites with enough resolution to provide the degree of certainty that is currently exibited. I have to logs of the St. Roch voyage in 1944. There were times when no ice was evident as far as the eye could see. This log is not in the public domain so I can't post a link to it. I can however post this: Page 92: Aug 22, noon. Barrow St. No Ice in sight. Page 93: Sep 3rd 6:pm Princess Royal Is. No ice in sight. RCMP 1945 Reports and Other Papers Realating to the Two Voyages of the R.C.M. Police Schooner "ST. Roch" This is first hand observations by the ships Master. Also, after reading the logs it is very apparant that the currents in the Arctic Sea play a huge role in ice transport etc. There is no doubt that the ice since Satillite measurements has been in decline. The reasons for said decline can be partially attributed to Global Warming, but a very significant part are the result of black carbon. Nasa Aerosols May Drive Arctic The long term picture is a complicated one that deserves much more research.
64144. Rob Painting at 12:01 PM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Layzej - John NG needs to bone up on the latest research. No one is suggesting that increased levels of CO2 won't benefit plant growth - all things being equal. But that's just it, they are not equal, and recent studies find little evidence for it on a global scale. We (SkS) know that the carbon cycle models used in the last IPCC (2007) report expect a CO2 fertilization effect, a huuuuge CO2 fertilization effect. But isn't it interesting that previous work on historic forest growth in North America over the last few centuries found no evidence for it? The latest global forest inventories show that the uptake of CO2 by land plants is occurring because of forest re-growth, (forests chopped down and allowed to grow back) not because plants are lapping up the extra CO2. The prime areas of reforestation are in the former Soviet Union, China and in the tropics. On a global level there seems to be little evidence of the CO2 fertilization effect. This makes perfect sense, re-growth areas can chew through a fair amount of CO2 as they grow into mature forests and incorporate the extra CO2 into plant mass, but mature forests have a limited capacity for further growth. " I had looked at the site...unfortunately they can't bring themselves to admit that the evidence, while complex, does point to a net overall benefit to plant growth for the next few decades." Or perhaps the correct answer is that John Nielsen-Gammon is conflating forest re-growth (areas where forest has been allowed to re-establish) with the CO2 fertilization effect. I get the impression he can't be bothered accurately researching this topic. Maybe he needs to consult Stephen Pacala? As far as the consequences for human agriculture - which is the subject of Dawei's post, that doesn't look too flash either. Many human crop foods will be negatively impacted by rising temperatures and drought over the next few decades, including main staples such as corn and rice. And what about ocean acidification? Global warming's evil twin? Dude, there are many reasons to limit CO2 emissions, focusing on one tiny detail blinds one to the 'big picture.'
64145. skywatcher at 11:40 AM on 12 February 2012
       A prelude to the Arctic melting season
       #4, and yet when the full context of the whole Arctic ocean is considered with a broad range of historical and proxy evidence (and not just the seas marginal to Russia), in this thorough review by Polyak et al 2010, they find:

       The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities.

64146. Doug Hutcheson at 11:40 AM on 12 February 2012
       The Year After McLean - A Review of 2011 Global Temperatures
       Bernard J @ 12 I am frustrated by my lack of the maths knowledge to answer your questions, but they seem to me to be interesting.

       can you tell us what period of time is required to discern from the short-term noise in the global surface temperature record, a warming signal of, say, 1.0 C/century? What period of time would be required to discern a signal of 0.75 C/century, and what period of time would be required to discern a signal of, say, 1.25 C/century? Conversly, and importantly in the context of your fixation with periods of approximately a decade, what rate of temperature change would be required to discern a signal from noise over a period of ten years? What rate of temperature change would be required to discern a signal from noise over a period of five years, and what rate of temperature change would be required to discern a signal from noise over a period of fifteen years?

       I imagine the answers would involve quantifying the average magnitude of the observed noise over the periods in question and then establishing the magnitude of signal required to skew the slope of the total data (noise + signal) by a statistically significant amount. It is so frustrating to be able to frame such problems, but not have the education to address them. If only I could go back to about year 10 at school and have teachers who could inspire me with the enthusiasm for math and physics that I have now, in later life. As it is, I have to rely on other minds to spoon feed me. So much to learn, so little time. To put me out of my misery, are those questions valid and are there answers to them? (And where can I go on the web to study high-school math and physics at my own pace ... I wish.)
64147. Tom Curtis at 11:40 AM on 12 February 2012
       A prelude to the Arctic melting season
       Camburn @4, the abstract of your cited paper reads:

       "Examination of records of fast ice thickness (1936–2000) and ice extent (1900–2000) in the Kara, Laptev, East Siberian, and Chukchi Seas provide evidence that long-term ice thickness and extent trends are small and generally not statistically significant, while trends for shorter records are not indicative of the long-term tendencies due to large-amplitude low-frequency variability. The ice variability in these seas is dominated by a multidecadal, low-frequency oscillation (LFO) and (to a lesser degree) by higher-frequency decadal fluctuations. The LFO signal decays eastward from the Kara Sea where it is strongest. In the Chukchi Sea ice variability is dominated by decadal fluctuations, and there is no evidence of the LFO. This spatial pattern is consistent with the air temperature–North Atlantic Oscillation (NAO) index correlation pattern, with maximum correlation in the nearAtlantic region, which decays toward the North Pacific. Sensitivity analysis shows that dynamical forcing (wind or surface currents) dominates ice-extent variations in the Laptev, East Siberian, and Chukchi Seas. Variability of Kara Sea ice extent is governed primarily by thermodynamic factors."

       (My emphasis) How small are the long term trends, to 2000, can be seen by noting the ice extent trends across all all four Russian Arctic seas of -0.5 thousand km^2 per decade. That means, averaged across all four seas Arctic sea ice extent fell by about 5 thousand km^2 over the twentieth century. In stark contrast, August Arctic sea ice extent has fallen by approximately 2.3 million km^2 over the last three decades: That is not an apples and oranges comparison in that it compares the entire Arctic to just the four Russian Arctic seas. Comparing summer Arctic extents over the 20th centuries show those seas to have been unusual in their limited reduction in August sea ice. That calls into question your extrapolation from a regional study to the full Arctic. Never-the-less the full comparison still shows Arctic summer sea Ice Extent to have fallen almost as much in the 21st century as it did throughout the twentieth. It is interesting to note that all of the fall in the twentieth century is post 1950. In other words, the clear pattern is that while NAO may influence Arctic sea ice extent, that influence is now imposed on an unprecedented (in modern times) long term decline in sea ice extent which is a consequence of global warming. Put differently, the difference between the 2011 and 2012 sea ice extent near Novaya Zemlya may be due to the NAO, but the difference between 2012 and the 1976-2006 mean is due to global warming:
64148. michael sweet at 11:28 AM on 12 February 2012
       CO2 is plant food? If only it were so simple
       Layzej: You have come to the right place for answers. All you need to do is read the opening post for the thread you have posted on and you will find Skeptical Sciences response to your question. If you have any more questions after you have read the opening post feel free to post them.
64149. muoncounter at 11:25 AM on 12 February 2012
       CO2 is plant food? If only it were so simple
       lazej#76: Curious that you omit Fact #1: A small concentration of CO2 is a big deal. and Fact #2: The fraction of CO2 molecules in the atmosphere that were produced by man is different from the fraction of CO2 molecules in the atmosphere that are there because of man. He goes on to say that man-made CO2 is indeed causing warming. Both of these are part of the same litmus test. If you hear or read somewhere that the amount of carbon dioxide in the atmosphere is so small that it must be unimportant, your source is either too naive to know better or trying to deceive you. ... If you hear or read somewhere that the amount of man-produced CO2 in the atmosphere is only a small fraction of the total CO2 in the atmosphere and that therefore man is having a small effect, your source is either too naive to know better or trying to deceive you. Further comments on JNG's post take issue with his dismissal of SkS' argument.
64150. muoncounter at 11:10 AM on 12 February 2012
       A prelude to the Arctic melting season
       I'm curious to know what the pro ice-watchers think of this: NASA Finds Russian Runoff Freshening Canadian Arctic Increasing freshwater on the U.S. and Canadian side of the Arctic from 2005 to 2008 is balanced by decreasing freshwater on the Russian side, so that on average the Arctic did not have more freshwater. Here blue represents maximum freshwater increases and the yellows and oranges represent maximum freshwater decreases.

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