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Comments 106801 to 106850:

  1. Despite uncertainty, CO2 drives the climate
    #18 You need to google the term Capacity Factor. If you want to compare Wind to Nuclear, take the Wind number and divide by 5. In the U.S., at least, wind turbines run at 20% of capacity and nuclear plants are in the high nineties.
    Moderator Response: Reminder to everybody, please do not delve into issues of competing energy technologies here on Skeptical Science.
  2. Throwing Stones at the Greenhouse Effect
    TOP, JMurphy linked to the section of this site that answers your question, but here it is more explicitly. Links for 'Greenhouse effect has been falsified' One of those links is to Jennifer Marohasy's blog where she talks about "fictitious atmospheric greenhouse effects".
  3. Despite uncertainty, CO2 drives the climate
    #21 As I have already said (#12), the problem was with dana1981 reproducing the graph without the caption explaining in the first sentence that the baseline was 1950-80. Dana1981 made the graph proofy by using Figure 3 instead if Figure 1.
  4. DMI and GISS Arctic Temperatures: Hide the Increase?
    muoncounter, regarding, "Lots of red except in the summer, where one would have expected the most red. " You'll want to be careful not to confuse temperature anomaly with absolute temperature. If the baseline is -30 C, a plus 5 C anomaly is still colder than a +1 anomaly on a -1 C baseline. I would expect the Arctic to show a greater anomaly in the winter than the summer. The frozen Arctic Sea has a very high albedo; this means that less of the light in the visible spectrum and above will be converted to infrared in comparison to other, non-ice-covered parts of the world. CO2 acts on infrared (and a some microwave), not visible and UV. Albedo means nothing in the dark. You might also consider that an enhanced greenhouse effect results more in higher relative nighttime temperatures than in higher daytime temperatures, and the arctic winter is more or less one long night.
  5. Despite uncertainty, CO2 drives the climate
    @muoncounter: considering there are 8760 hours in a year, 150 billion KWh (or 150 TWh) gives approximately 17 GW or power, not 17 MW. 150,000,000,000,000 ÷ 8760 = 17,123,287,671.23
  6. Throwing Stones at the Greenhouse Effect
    Also: "The sun's powerful high frequency ultraviolet radiant energy can easily pass through the windows to warm the house" Not all windows let through UV rays. However, since a lot of the radiated energy is transmitted through visible light, your overall point still stands.
  7. Throwing Stones at the Greenhouse Effect
    @Roger (20): "Why are nearly 75% of Americans, American news media, and American politicians deniers?" Take comfort in knowing that, outside the US, the proportions are pretty much reversed.
  8. It's the sun
    I'm sorry, Ken, can you explain this to me in layman's terms? This site does a great job at explaining concepts in everyday language, you should follow that example.
  9. Throwing Stones at the Greenhouse Effect
    Just out of curiousity, who is disputing the Greenhouse Effect to point where it is in dispute?
  10. Throwing Stones at the Greenhouse Effect
    "By comparing the Sun’s heat reaching the Earth with the heat leaving it, we can see that less long-wave radiation (heat) is leaving than arriving (and since the 1970s, that less and less radiation is leaving the Earth, as CO2 and equivalents build up). Since all radiation is measured by its wavelength, we can also see that the frequencies being trapped in the atmosphere are the same frequencies absorbed by greenhouse gases." This is not accurate. One needs to compare the sun's and the earth's radiant intensities across their respective spectra. I can imagine the earth as a converter of higher frequency, shorter wavelength solar photons into lower frequency longer wavelength terrestrial photons.
  11. Throwing Stones at the Greenhouse Effect
    It seems a simple question, but teh question of the Moon's temperature does come up. It usually takes the form: "You tell us that without the greenhouse effect, Earth would be -18C average temp. But the moon has no atmosphere and is roughly the same distance from the sun. Its temperature varies wildly from extreme cold to extreme heat. Earth would be the same if it had no atmosphere, so the greenhouse effect must be false". SoD has a long explanation involving averages and heat capacity. Is there a shorter explanation for the non-physics major?
  12. Throwing Stones at the Greenhouse Effect
    Overall, this is a good post. Yet oddly, after making its basic point so well, the post suffers from a fit of diffidence that deprives it of much of its potential vigor. I refer to the 'might' in "What the Earth might be like without an atmosphere that sustains the greenhouse effect". 'Might'? Isnt' the whole point of the post that the greenhouse effect has NOT been falsified? Isn't the whole point that there is no serious doubt about it? For this reason, it should read 'would' not 'might. Look yourselves at how much more vigorous it is with this change (and a minor tense change, too): "We only have to look to our moon for evidence of what the Earth would be like without an atmosphere that sustains the greenhouse effect. While the moon’s surface reaches 130 degrees C in direct sunlight at the equator (266 degrees F), when the sun ‘goes down’ on the moon, the temperature drops almost immediately, and plunges in several hours down to minus 110 degrees C (-166F). "
  13. Despite uncertainty, CO2 drives the climate
    Joel, I have the opposite problem from you. I think the baseline should be set at 1850 so that the rise reflects all the temperature increase from the start of the idustrial era. We can compromise by choosing the time frame when the graph was originally started, say 1950-1980. That corresponds to when I was a child so it makes sense to me. Oh wait, that is what they did.
  14. Throwing Stones at the Greenhouse Effect
    Strangely enough, one of the best resources on the greenhouse effect is on Dr Ray Spencer's blog. He is a skeptic, but only on feedbacks, not on the greenhouse effect. See here
  15. Roger A. Wehage at 01:56 AM on 19 October 2010
    Throwing Stones at the Greenhouse Effect
    My subterranean house has no furnace or air conditioner, but relies on natural means such as solar heating and energy storage to maintain comfortable temperatures year round. Its many south-facing windows have high incoming solar heat gain and high resistance to outgoing heat flow. What does that mean? The sun's powerful high frequency ultraviolet radiant energy can easily pass through the windows to warm the house, but the house's and my low frequency infrared radiant energy cannot easily pass back out through the windows to make us feel cold. Since a significant percentage of energy transfer is by radiation, how can one teach energy transfer concepts without introducing the radiant energy concept? Maybe replacing "radiation" by "energy transfer through electromagnetic wave propagation" would be useful. The whole issue is, what happens as different electromagnetic waves propagate through mass. Most of us know what a microwave oven does to water. It's electromagnetic energy excites the H2O molecules and warms them and the food containing them. Other electromagnetic waves are no different. Higher frequency/higher energy ultraviolet waves from the sun have little effect on CO2 molecules, but they do excite most solid and liquid atoms and molecules in the earth. These excited atoms and molecules, in turn, emit lower frequency/lower energy infrared waves that do excite CO2 molecules, causing them and the atmosphere to heat up. The real issue for debate ought to be, does every CO2 molecule have the same chance of being heated by the outgoing infrared electromagnetic waves? That is, if 10% more CO2 molecules are added to the atmosphere, will 10% more energy be absorbed with a similar change in atmospheric temperature, or will a smaller or larger percentage of energy be absorbed with less or more effect on temperatures? The answer to this question might hinge on the percentage of infrared energy currently being absorbed by CO2. If that percentage is low, then one might expect increasing CO2 levels to have a higher impact on atmospheric temperatures. If that percentage is high, then increasing CO2 levels would likely have a smaller impact on atmospheric temperatures.
    Moderator Response: The "real issue" you raised is addressed in the Argument CO2 effect is saturated.
  16. Throwing Stones at the Greenhouse Effect
    The Inconvenient Sceptic, have a look at two of the pages on Skeptical Science here and here (as suggested by Tom Dayton) - although the second page appears to have quite a few spurious links, for some reason. Read the so-called skeptical 'arguments' and wonder. Also, see this paper from Gerlich & Tscheuschner, and this blog post from Roy Spencer.
  17. Throwing Stones at the Greenhouse Effect
    An underused feature of this Skeptical Science site is the collection of links to claims for and against the existence of anthropogenic global warming, categorized into Pro, Skeptic, and Neutral. Click the "Links" link in the blue horizontal bar at the top of this page. The red numbers are the number of skeptic articles linked. Additions to the list are very welcome.
  18. Greenhouse effect has been falsified
    Tom #65 The Mythbusters experiments sufferers the same problem than invalidates many Mythbusters experiments. The lack of replication and randomisation of placement of the treatments. I'd love to see someone do the experiment properly, but none that I have seen on the internet so far come close to a properly controlled, replicated and statistically analysed experiment. It's odd really. You'd think that every natural history museum in the World would have this sort of thing as a permanent installation.
  19. It's the sun
    archisteel 3691 "TSI is warming the planet. How could radiated energy cause the planet to cool?" Its called IR cooling from S-B equation proportional to T^4. In 2005 at about minus 2.8W/sq.m. due to a 0.75degC warming since AD1750. IR radiating temp is currently about 255degK. Which was 254.25 degK in AD1750. The sum is roughly (255/254.25)^4 x 240 = 242.8W/sq.m where 240W/sq.m is the original IR outgoing from the planet. Hence IR outgoing increases proportionally with (T2/T1)^4.
  20. Throwing Stones at the Greenhouse Effect
    I teach climate change science to college undergraduates, and give climate change presentations to interested public groups. I have had success explaining the 'Greenhouse Effect' as the 'blanket effect'. Most people understand that blankets impede the movement of heat from your skin to the cold room and raise your skin temperature, and making the analogy between carbon dioxide levels and the thickness of a blanket seems to provide many people with a mental image they can work with. Also, I have found it useful when explaining the greenhouse effect to avoid the word 'radiation', as in 'solar radiation', as anyone not a physical scientist is likely to associate 'radiation' with nuclear decay, and not electromagnetic radiation. As soon as you say 'radiation', you have lost a large part of the audience. I am a great fan of Skeptical Science's work to present complex scientific concepts in a way that makes those concepts accessible to a wider audience. I steer people to this website often. My thanks to John and all the contributors to this site.
  21. It's the sun
    KR #692 I pulled out a chart of CO2 concentration from AD1750 and used the IPCC quoted equation to calc the forcing F.CO2 for a range of dates: F.CO2 = 5.35ln(CO2*conc/280) W/sq.m where CO2*conc is the well mixed global concentration in ppmv at any point in time. F.Solar in W/sq.m is from IPCC 2007 Fig 613. Here are the numbers: Date/CO2*conc/F.CO2/F.Solar AD1850 / 290 / 0.18 / 0.2 AD1900 / 295 / 0.28 / 0.1 AD1950 / 310 / 0.54 / 0.4 AD1975 / 335 / 0.96 / 0.4 AD2000 / 370 / 1.50 / 0.45 AD2005 / 382 / 1.66 / 0.4 (estimated) Until circa AD1950 the F.CO2 did not overtake the F.Solar and in AD2000 it was 3x and only in AD2005 had it reached 4x. Again it is the area under the curve which represents the total available energy from both sources and both add together as I have calculated elsewhere back to AD1750. S-B radiative cooling has grown to -2.8 W/sq.m to date as a climate response to 0.75 degC warming.
  22. The Inconvenient Skeptic at 00:39 AM on 19 October 2010
    Throwing Stones at the Greenhouse Effect
    Craig, I apologize for causing you to feel insulted by my feeling insulted. :-D I suppose that this website would see plenty of claims that the GHE isn't real. I accept the need for articles like as a result. Three cheers for Calculus!!!
  23. Throwing Stones at the Greenhouse Effect
    TIS #3 A quick Google search pulls up 31,000+ pages with people claiming that the greenhouse effect is bunkum because (they claim) it violates the second law of thermodynamics. I feel insulted by your pretence at feeling insulted.
  24. Despite uncertainty, CO2 drives the climate
    #18: See the graph here. Projection for China's nuclear energy in 2020 is given as 150 billion kwH; this works out to 17 MW of generating capacity.
  25. Throwing Stones at the Greenhouse Effect
    TIS #3: Your lack of awareness of people who deny the greenhouse effect is not the same as them not existing. It is an exceedingly common claim amongst 'skeptics'. Indeed, I thought you'd been on some of the threads where people were claiming that the greenhouse effect contradicts the first and/or second law of thermodynamics. If not, just do a search on 'thermodynamics' and you'll get more than your fill. Might have been something to try BEFORE accusing the author of making up an "inaccurate" straw man argument that no one really uses.
  26. Throwing Stones at the Greenhouse Effect
    Thanks for the excellent example: MOON ... it is just striking, and actually it would be nice to know about the distribution of temperature on the surface of the moon. Does anybody know where to find those data? What is the heat capacity of the rocks of the moon? Anybody knows??
  27. The Inconvenient Skeptic at 23:29 PM on 18 October 2010
    Throwing Stones at the Greenhouse Effect
    I am not aware of anyone saying there is no greenhouse effect. I certainly agree that there is a greenhouse effect. The atmosphere certainly keeps the Earth much warmer than it would be otherwise. It is the importance that CO2 plays in the greenhouse effect that we disagree about. The total greenhouse effect includes all energy going into the atmosphere. Convection and evaporation also play an important role in transferring energy into the atmosphere. I will gladly mock anyone that says the atmosphere doesn't insulate the Earth and keep it warmer. However, this article is inaccurate as I am not aware of anyone claiming that the atmosphere doesn't have an effect. This article seems intentionally written to insult people that disagree with the theory that the currently increasing CO2 is going to significantly alter the Earth's climate. They are separate and independent issues in every way.
    Response: Sadly, there are many who deny the greenhouse effect and there have been many comments on this site to that effect. Just the other day, someone emailed me an article purporting to disprove the greenhouse effect. There are various levels of climate skepticism and unfortunately, we have the job of addressing them all.
  28. Roger A. Wehage at 22:45 PM on 18 October 2010
    Throwing Stones at the Greenhouse Effect
    JMurphy, there can be only two ways of life: What we do and what we must do. Unfortunately what we do makes us feel good and what we must do does not. Why are nearly 75% of Americans, American news media, and American politicians deniers? Because acknowledging the truth would make us feel guilty for not doing what we must. Make us feel guilty for condemning our offspring to unimaginable futures. But that's not all. What are the other 25% of non deniers doing? Mostly a lot of lip service and hand waving? Are we really changing our lifestyles, or could we even if we tried? What significant changes and sacrifices are we making to lead the way? 350.org is a great concept, but it barely scratches the surface. The world will need thousands of proactive groups like 350.org if we are to overcome the momentum of life as it is.
  29. Despite uncertainty, CO2 drives the climate
    Joel wrote: "I'm currently reading "Proofiness" by Charles Seife and one of his first example of a misleading graph is setting the index at a place where the reader doesn't expect it." Which is entirely subjective. Most readers expect the baseline for temperature anomalies to be an average over the timeframe of the data series or some portion thereof. Your apparent expectation that it would be the average over the year 2010 (which isn't over yet... so, what, recalculated daily?) is highly anomalous. Your claim that a graph which doesn't conform to YOUR assumptions is intentionally "misleading" says alot more about you than it does the graph. In short, you're looking for excuses, and incredibly thin excuses at that, to find fault... so, of course, you will.
  30. Throwing Stones at the Greenhouse Effect
    I still can't understand how anyone could dispute such basic science facts, unless it's a trend among some to reject all science unless they themselves can prove results by personal experience alone. Some even seem to think that they are more intelligent than anyone else and are able to discard scientific proof because they know the 'true facts' - as opposed to the facts produced by 'elitist' scientists who are only out to enrich themselves and help governments enslave us all, apparently. The reality is, of course, that such people - deniers of any science they don't like, not just AGW - are arrogant, self-deluding and blind to reality.
  31. bgood2creation at 16:02 PM on 18 October 2010
    DMI and GISS Arctic Temperatures: Hide the Increase?
    "In the Arctic Summer when the surface ice is melting, it is known that the air temperature close to the surface is limited by this ice melt temperature to just above zero degrees C, (Rigor 2000)." This basically has to do with the heat of fusion, right? Anyway, regardless of the Arctic Summer temperature trend, the length of the melt season grew longer by an average of 6.4 days per decade from 1979 to 2007, according to NASA. http://www.nasa.gov/topics/earth/features/longer-melt-season.html
  32. Climate Change Impacts on California Water Resources
    There's already a lot of acrimony over trying to keep Californian River flows high and cool enough for salmon. Regardless of scenario, I guess it's good-bye to California's salmon.
  33. Despite uncertainty, CO2 drives the climate
    archiesteel #15 - you didn't miss anything, the baseline is completely unimportant.
  34. Despite uncertainty, CO2 drives the climate
    This discussion may be trending off-topic. Nevertheless... The advent of of natural gas production from shales, made possible through the improvements in drilling and hydraulic fracturing technology, has radically altered the notion of "peak oil". The resource potential of shales is immense. Electricity generation from natural gas results in approximately 37% less carbon emissions than coal, for an equivalent amount of energy... but that's still 63% more than zero. At this point, energy supply is driven by market economics (not quite "free"-market!), and coal remains an economically viable energy resource. Even if world oil production begins to decline, there's still plenty of fossil carbon available to generate energy... and... .er.... CO2 as a by-product. Environmentalists who were counting on "peak oil" to reduce the rate of carbon emissions will likely be disappointed, despite the environmental benefits of natural gas. It will require some sort of artificial "meddling" in the marketplace to substantially alter this trend.
  35. Despite uncertainty, CO2 drives the climate
    muoncounter @13... That's interesting that China is shooting for 75MW (surely they mean GW) by 2020. They're shooting for 230GW in wind by the same time.
  36. Despite uncertainty, CO2 drives the climate
    Oil's part of the problem, Joel, coal is the biggest. Here's some data on where coal is headed: From United States Energy Information Administration Notice that population does not track coal consumption; your correlation is specious. The swerve you see post-2002 continues; for 2008 production was 7,271,249 thousand short tons. There's lots more coal available, dirtier going forward, but plenty to burn unless we choose to do otherwise. This business of changing the baseline seems simply an exercise in politically correct thinking.
  37. Despite uncertainty, CO2 drives the climate
    Joel, Take a step back and try to understand that you are not the first person to understand the problems with extrapolating current trends into the future. BTW, isn't this what you are doing by predicting a date for when China will have more nuclear plants than coal plants. You should also realize that does not mean that they will have less coal plants than they have now. Also try to understand that there is more than one scenario in AR4. These predictions of the future are much more, 'If A happens, we can expect B to be a result.' than they are a prediction that 'A will happen'. Lastly, please explain your math. Pre-industrial levels of CO2 were about 287 ppm. Currently we are at about 388 ppm. So, we are about 1/3 of the way to a doubling already. The levels are increasing by about 2 ppm currently. Even if the current levels of production stop growing immediately, at the current rate, we'll reach a doubling by around 2010 + ((287ppm*2) - 388ppm)/(2ppm/yr) = 2103. Wow, that is _so_ far off from 2100. However, if you look up the levels of CO2 in the atmosphere, there is every indication that the rate of increase is increasing, and not decreasing. So, there is every indication that a doubling will be reached before then, and no indication that any reduction will occur without some form of intervention. Peak oil will happen; it's just a matter of when, but there are plenty of other sources of fossil fuel around. Incidently, if you look at US Department of Energy predictions, there is no reduction of fossil fuel use expected. Regarding, "there shouldn't be any need to reset the baseline". Umm, you are right, and most of the baselines were established 30 years ago or more. Then again, as has been pointed out repeatedly, if the audience can read a graph, why does it matter?
  38. Despite uncertainty, CO2 drives the climate
    Uh, maybe I missed something, but what difference does it make where the baseline is?
  39. Despite uncertainty, CO2 drives the climate
    If you set up the spreadsheet correctly, there shouldn't be any need to reset the baseline. You should be able to set it up to draw the X and Y crossings corresponding to the current date. An alternative would be to have the spreadsheet draw a symbol at the current date. Sort of like the You are Here symbol on a mall map.
  40. Despite uncertainty, CO2 drives the climate
    #10: "since it assumes it is actually possible to triple out production of fossil fuels. ... Ever hear of peak oil?" Have you ever heard of coal? China is #1 in CO2 emissions (total, not per capita) for the past few years, primarily due to their most abundant source of energy: Coal. Coal's CO2 emissions per kwh of electricity generated is much higher than petroleum. See Table 1 here. As far as China's nuclear industry, they are shooting for 75 MW by 2020, up from 9 MW now. That's still a drop in the bucket, especially if you go with per capita energy needs for a 'developing' nation.
  41. Despite uncertainty, CO2 drives the climate
    #8 When I looked at the reference you gave, Figure 1 explained in the first sentence what the baseline was, so saying that scientists don't have to explain that seems kind of spurious. Why don't you use the graph that explains explains the baseline?
  42. Despite uncertainty, CO2 drives the climate
    Incidently, Stephen Schneider at one point thought that particulates would dominate the effect of CO2 and that cooling would prevail. This was one source, if not the main source, of the media splash on 'global cooling'. Not very much later, he retracted that position with the admission that he'd gotten some of the math wrong. This was in the 1970s. So, it's not an easy determination to make, but more is known now than it was then.
  43. Climate Change Impacts on California Water Resources
    http://www.onlineopinion.com.au/view.asp?article=11063 provides information on the findings of the GRACE satellites. Although the importance of California’s Central Valley to US agricultural output seems over-stated, the fact is that dwindling water supplies have already resulted in population/agriculture competition for the inadequate supply available. Outcome to date is that population needs are being met. Those of agriculture are not. Aquifers are already being pumped at unsustainable rates in a bid to overcome shortage of water for agriculture and yields are falling. This is happening in 2010. With predicted population growth and the effects of climate change by 2050, agriculture in its present form will no longer be possible. As in Australia, farmers will have to learn to use water in a more cost-efficient and effective manner, growing those crops which provide the best returns, given the price of water. Farmers do not have until 2050 to learn how to make best use of water. They must do so now. Those that do not will go out of business and crop yields will fall further as population increases.
  44. Despite uncertainty, CO2 drives the climate
    #4 & #5 lets me use another section of "Proofiness" that the author call "regression to the moon". The example was some scientists that analyzed men and women sprinting records and did a linear projection and concluded that women would beat the men in the 100 meter in 2154. This paper actually got published in Nature. Doing a linear projection of carbon emissions for 10 year would be fairly reasonable assumption. For 20 years, not so much. For 90 years, it is gibberish. The way I see it, we have three kinds of countries. Developed countries Developing countries, and not so developing countries. In rough numbers, since I'm too lazy to look it up, call it 2 billion developed, 2.5 developing and 2.3 NSD. The developed counties are all at ZPG or below. The developed countries have fairly flat carbon emissions per capita and they will have less people by 2100, so their carbon emissions will be flat or decrease by 2100. The NSD counties will have a lot more people, but they won't be able to use a lot more fossil fuels, because they don't have the money to buy or the infrastructure to use a lot more fossil fuels. If fuel prices go up a lot, then they might actually be using less. Developing counties eventually become developed counties, like former developing countries like Taiwan, Korea and Singapore. I figure China gets there about 2040 and India by 2060. At that point their emissions per capita flatten out and their population decreases. China is already at ZPG and India should be there in 10 years of so. Above is rather simplistic, since it assumes it is actually possible to triple out production of fossil fuels. Does anyone actually think we will producing three times as much petroleum in 2100? Ever hear of peak oil? We would be extremely lucky to maintain our current production. Part of this will be addressed by tar sands and shale oil, but at much higher prices. This also opens opportunities for renewables to grab part of the market and makes hybrids and electric cars a reasonable purchase without tax subsidies. There is also a reasonable case that we can't triple our production of coal either. China has already started importing coal, but the are limits to how much coal they can practically import. China has a nuclear power program that is growing by leaps and bounds. They will have more nuclear plants than the United States by 2025. By 2040 nuclear plants will be displacing coal plants. That is about the year when China estimates that the CO2 emissions will flatten out. A few years after that it will start go down.
  45. Despite uncertainty, CO2 drives the climate
    There are a few requirements to define the baseline for the temperature anomaly, the first being that it cannot be any single year. Being it an average over 30 years, it's better if temperature didn't change much over that period. Finally, you want the best data possible, and this excludes any 19th century period. The three decades 1950-80 look very appropiate.
  46. Despite uncertainty, CO2 drives the climate
    Joel, I find your argument that something which is the norm and which everybody is accustomed to is "misleading" very hard to swallow. Anyway the figure is from a peer-reviewed scientific paper and used in an Intermediate level rebuttal. In both cases the audiences should know how to read a simple graph, and if they don't, they can always ask.
  47. Despite uncertainty, CO2 drives the climate
    Not to sound overly reactive, but how often should we reset the baseline, Joel? Every year? And by your recommendation, why should the baseline not be set to any arbitrary year we choose, as opposed to 2010? What's so special about 2010 in the statistical record? The cynic in me imagines that trying to shorten the longitudinal perspective this way has an objective of comfort as opposed to cold-hearted assessment.
  48. Despite uncertainty, CO2 drives the climate
    #3. I know that is a common convention and it is always misleading, especially when you clip the graph out of context, so we don't know what the 0 degrees represents. You said "Note that even with the lower climate sensitivity, the model shows the planet warming 3°C by 2100 in this emissions scenario.". Did you mean 2010 or 1950-80? Most people reading it weren't born in 1950 and a lot of them weren't born in 1980 and are going to assume that you meant it was going warm 3 degrees between 2010 and 2100. If you can't re-normalize the data to the current year, then at least mark an X and label it 2010.
  49. DMI show cooling Arctic
    HumanityRules at 01:18 AM on 18 October, 2010 Thanks, I have corrected this now.
  50. DMI and GISS Arctic Temperatures: Hide the Increase?
    The Inconvenient Skeptic at 22:27 PM on 17 October, 2010 Atlantic Multidecadal Oscillation (AMO) is derived from detrended North Atlantic SST variation. So your point is regional SST and Surface air temperatures correlate? We would intuitively expect some correlation, but what is driving the SST in this area upwards (as we see if we leave the trend in) and what is driving the multidecadal variations? SST in the North Atlantic appears to be driven by a combination of atmospheric forcing and possible meridional heat transport. What is the source of this underlying increasing thermal energy in both cases? You may consider the facts that the North Atlantic SST variability is strongest at the surface and is also strongest at higher latitudes. I will try to get time to dig out recent work in this area, but here is some more inconvenience for you, as it does not appear that AMO leads surface temperature. If anything the reverse looks likely, though I would be cautious here. The AMO is de-trended North Atlantic SST from NOAA ESRL and I have de-trended the HadCRUT3 surface temperatures also to allow comparison.

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