Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

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

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  1027  1028  1029  1030  1031  1032  1033  1034  1035  1036  1037  1038  1039  1040  1041  1042  Next

Comments 51701 to 51750:

  1. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    Sphaerica, Good explanations. Thanks. I'm almost there. One last thing will clinch it for me. You explained very well why the ice in Antarctica is colder than the Arctic. However, why is the stratosphere over the Antarctic colder than the stratosphere over the Arctic?
  2. It's El Niño
    Frankly, I would think you would pounce on the opportunity to rip this particular ’skeptical’ argument apart, to present a clinical, blow-by-blow refutation of it. It is (still in MY opinion, though) the most robust, cohesive skeptical argument AGAINST an anthropogenic and FOR a natural cause of global warming out there. And it’s getting more and more traction amongst ’the skeptical crowd’. So it is indeed a real, important and relevant skeptical argument. It is an easy to grasp argument, mostly descriptive actually, and does not make use of any models or sets of novel assumptions, only available data. The physical mechanisms at work and their effects are readily observable through space and time and well known and described in the geophysical literature. In a way the argument explains itself once you understand the processes at hand and simply track the energy through the Earth system by looking at the various sets of data. If you’ll let me, I would be happy to give you a compendious summary of the argument.
    Moderator Response: [DB] As noted by Phippe and KR below, the skeptical thing to do would be to first address those questions already put to you on this thread. Those genuinely interested in advancing the scientific understanding should feel that to be an imperative.
  3. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    JoeT, Please note that this geographic and mechanical difference in the two systems (ocean surrounded by land in the north, land surrounded by ocean in the south) are at the core of the above post (i.e. the apples/oranges aspect of the whole thing). The differences are very dramatic and important.
  4. Renewables can't provide baseload power
    The island of Hawaii used to obtain much of its electricity as a byproduct of sugar cane agriculture, with crushed cane (bagasse) burned as a fuel source. With the demise of sugar cane the cane processing plants were closed and generation moved for a period of time to the ultra-primitive combustion of bunker oil. So with the advent of PV, wind and geothermal power Hawaii is clawing its way back to replace the biofueled generation it used to enjoy, thereby eliminating the wretched compromise of fossil hydocarbons. My brother is just now having a 9.5kW array placed on his roof. There's a third party involved that finances this installation and sells electricity to Helco. Customers still pay a bill but it's vastly less than before; even with fairly scrupulous attention to waste and solar DHW my brother's electric bill has typically hovered around $400/month. Electricity rates would have been going down on Hawaii thanks to all the modern generation capacity being installed but the remaining paleolithic combustion systems are drastically affected by bunker fuel costs, which have skyrocketed thus erasing savings. There's a lesson for all of us in that. The Big Island's Hawaiian Electric Company (known to locals as "Helco") publishes quite a bit of information about integrating modernized power generation with the old gear, for the curious.
  5. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    JoeT, It's a little more complicated than that. I'm not claiming to be an expert, but... First, yes, it is colder at the South Pole, because Antarctica is a land mass with mountains, surrounded by ocean. The ice is piled on top of this land (snowfall there accumulates), and as you know temperature decreases with altitude. Thus, much of the ice there has no chance of melting, because even under the 24-hour summer sun, it doesn't get above freezing. By contrast, the Arctic is an ocean surrounded (for the most part) by land. As such, snowfall accumulates in the winter, but being at sea level it has the chance to melt back (more or less) in summer. At the same time, in summer the land masses around the Arctic heat and cause weather systems that push north. The oceans around Antarctica cause an entirely different (and more moderated) dynamic. This major difference in geography results in drastically different mechanics at the two locations, and much lower temperatures in Antarctica, which allows polar stratospheric clouds to form, which help to catalyze ozone depletion. My comment about Antarctica being a "closed system" was simply an analogy to the fact that the stronger polar vortex in the south (a result of the difference in land masses and temperatures) helps to contain things (temperatures, CFCs) over Antarctica in contrast to the Arctic, where the more moderated temperatures also allow for more of an exchange of air masses (what become winter storms for those in North America and Europe, but have the equal-and-opposite reaction of injecting warmer air into the Arctic itself). As far as CFCs being emitted in the north... I can't find a reference, but I would doubt that is much of a factor. Like CO2, things released into the air are going to wind up, over time, dispersing fairly evenly. What is of more importance is the creation of the right conditions (very cold temperatures and polar stratospheric clouds in the Antarctic) to allow CFCs to do their dirty work.
  6. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    Sphaerica, I'm not following your argument. Most of the CFCs were released in the north, so if Antarctica is a closed system, why is there an ozone hole in the south? A quick internet search to my question comes up with an answer that CFC affects ozone at very low temperature and a larger ozone hole is over Antarctica because it is colder there. The question then is moved to -- why is it colder to begin with? It looks like a positive feedback system would also be set up --- if it starts out colder, then the CFCs destroy more ozone. And since ozone is responsible for making the stratosphere warmer than the troposphere, the extra cold would have an even bigger effect. Sooooooo ---- why is the south pole colder to begin with?
  7. Skeptical Science now an Android app
    OK, first off, I am an old dog trying new tricks and thought I should finally download the app using a barcode scanner. The link to Droid apps doesn't work, but this link will: http://www.androidzoom.com/android_applications/qr+scanner I decided to download the QuickMark app. Doing this requires logging in with your Google or facebook account. OK, I used my facebook account. After that, it was very easy, and I soon realized that I didn't need to "expand" the barcode on this page. My phone squawked at me when it captured the barcode, which made it easier somehow. I think the app works very well!
  8. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    Although the increases in Antarctic ice maximums in no way balances the Arctic ice minimums, a visual study of the ice area/extent graphs does appear to show a link between these two events. Antarctic maximums in 2007 and 2012 correspond (in kind if not extent) with Arctic minimums. Recent explanations of Antarctic maximums ignore this link. Until until a physical link or a statistical anomaly can be shown this will continue to be a crutch for climate miss-informers (I don't believe there is such a thing as an informed skeptic!). Looking at the graphs I believe that there is a link that is not understood at present.
  9. Renewables can't provide baseload power
    The Los Angeles Times had this newspaper article in November 2012 discussing solar power in Hawaii. They have installed a lot of solar in Hawaii since their electricity is very expensive. The island of Hawaii gets as much as 44% of power from solar and the other islands get a lot of power from the sun. They had a target of 40% solar by 2030 and have already achieved that!! With rapid building of solar there are some problems. Each island has a separate grid. Since the grids are so small, it is hard to balance power output. A single big thunderstorm can significantly affect power generation. They have issues of how much to pay for solar power. They are looking at running power lines to connect the islands together to increase grid size. It appears that Hawaii will be an experimental site looking at large scale solar power production. They will have to solve the problems and the rest of us will be able to watch and learn. If anyone sees a technical article on Hawaii solar post a link here.
  10. 2012 SkS Bi-Weekly News Roundup #2
    I see no hope that cap-and-trade is going to solve anything. It haven't produced any results for 15 years but ending up as a speculation object. We have found a way to base our market economy on stealing from the future. Until the market reflects the true cost (including that to future generations) the market will only work against a solution, not towards it ... until it's too late. The only viable solution is (as James Hansen suggests) a 100% revenue neutral carbon tax with public dividend. Preferably the tax should be imposed on the source of fossil fuels: Where it's pulled from the ground. That should be easier to administer and the effect will ripple through the marked. ALSO: As opposed to cap-and-trade this can be put into place without initially global agreement. Simply impose penalty taxes on goods from countries without such a system. Of course it would be most effective if the US and the EU did this together, but we won't need China and India to do the same thing. It should pay of for them to do it simply to (re)gain access to our markets. It's important that this tax is revenue neutral. If it doesn't go 100% back to the public any part of it can only be spent to make it obsolete - like investing in carbon-free infrastructure.
  11. Heat from the Earth’s interior does not control climate
    Martin @25: It is wrong to call all that "solar", the 238.5 number you provide must be IR losses to space, not solar. When it comes to climate change, you need to focus on radiation change. The net IR change related to doubling CO2 is about 4 W/m^2. How much do you think the 0.09 W/m^2 geothermal heat flux has changed? How important is that compared to 4?
  12. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    JoeT, In effect, part of what made Hurricane Sandy into what it was is the same thing that is minimizing ozone depletion in the north.
  13. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    JoeT, There is greater air exchange between the pole and mid-latitudes in the North Pole than the South, I think primarily because of the differences in land masses. The end result is that ozone depletion is greater at the South Pole (the southern polar vortex creates more of a closed system over the South Pole).
  14. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    +1 on wanting to see more discussion of why the temp gradient would be increasing - and speeding up winds - in the SH, but decreasing - and causing the giant looping whorls in the jet-stream - in the NH. My assumptions are similar to mercpl's, but I had also believed the Antarctic ozone hole was slowly but significantly repairing. Given that in NH it's generally pointed out that the equatorial rate of warming is slight compared to the dramatic heating of the pole, a not-much-warmer equator and a slowly-healing Antarctic ozone hole would not at first glance appear to make for a steeper temperature gradient. Also: volume!
  15. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    Like JoeT, I was also struck by the statement that the temperature gradient between the Equator and the Antarctic is increasing. This is at opposite of what's happening in the Arctic is it not? I have also read recent reports of the warming of the Antarctic penisula. So are we only talking about the Antarctic Stratosphere? I understand that that has cooled because of the decline in Ozone which is in itself a powerful greenhouse gas. But then again I thought that Ozone levels were increasing because CFCs have been banned. So you could say that I am a bit confused. So here's my take of the explanation. 1. Ozone depletion causes the Antarctic Stratosphere to cool. 2. Cooling Stratosphere causes stronger west to east winds. 3. Stronger winds cause the ice to drift north, opening up more gaps. 4. These gaps encourage formation of new ice resulting in more ice area.
  16. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    A question about the ozone hole: Why is it predominantly over Antarctica? Why not over the Arctic as well? What's curious is that the temperature gradient is increasing in the southern hemisphere, but decreasing in the north.
  17. The Apples & Oranges of Arctic/Antarctic Sea Ice Trend Comparisons
    See also http://www.climatecentral.org/news/changing-winds-the-smoking-gun-in-antarcticas-growing-sea-ice-15246 over at Climate Central. Tamino had an extensive series of posts on this as well.
  18. Heat from the Earth’s interior does not control climate
    I'm a bit late, but I'd like to take issue with the statement about heat from the Earth's core: "The effect on the climate is in fact too small to be worth considering." Net solar heat flow is 341.3 - 101.9 - 238.5 = 0.9 W/m2 Heat flow from the core is 0.09 W/m2. That's 10% of the net heat flow. That's significant. Net gain from solar and core together is 0.99 W/m2.
  19. Fred Singer - not an American Thinker
    bahamamamma @12 - The other major difference is that GISS has ~99% global coverage, the older HadCRUT3 data in that graph has only about %80 coverage, with particularly poor coverage over the poles, which have seen most of the warming since 1998. This causes a significant cool bias in HadCRUT3 data. See this article and this article.
  20. It's El Niño
    Sphaerica - "Put another way, ENSO has been around for thousands of years" ENSO has been around for millions of years. There are enough people responding to Kayell, so I'll stay out of this.
  21. It's El Niño
    Kayell - "...claiming that the NINO3.4 index does not fully account for ENSO as a process..." I find this a very curious strawman argument. The NINO3.4 index is one measure (of many) of an acyclic process - consisting of wind driven changes in ocean overturn and hence heat exchange with the atmosphere. That index is not the process. I cannot think of anyone who has claimed it is (hence the strawman). It is, rather, one measure of that process, much as GDP is one measure of economic activity. If the ENSO index is insufficient to track the process, then what ENSO aspects does Tisdale think have changed in the 1970's? And why? How would he measure that, in a statistically significant fashion - where is his evidence? His favorite measure, sea surface temperature changes in various regions, is actually part of the NINO3.4 index; he's presented nothing new. As I said at the start, attacking the index is a Strawman Fallacy. The ENSO can be measured/tracked with trade winds, with atmospheric pressures (Southern Oscillation Index, SOI), or with sea surface temperatures (as in the NINO3.4 index). If Tisdale thinks these are insufficient, it is on him to present evidence of supportable process changes that have diverged from historic behaviors. He has not.
  22. It's El Niño
    Kayell - Tisdale's argument appears to be that the ENSO is not symmetric, that La Nina absorbs more energy than El Nino releases, and thus the heat content of the Earth rises in 'steps'. Problems with his hypothesis: * Why would the ENSO be asymmetric now, when it hasn't been for the last few hundred years - effects require causes and mechanisms, and he has proposed nothing plausible in that regard. * The oceans and the atmosphere have warmed, especially over the last 40 years - and given the Stefan-Boltzmann relationship of emitted power with temperature, if the atmosphere was radiatively unchanged we would have a negative (cooling) top of atmosphere (TOA) balance. The evidence shows a postive balance (less leaving than arriving), thus contradicting Tisdale. This is a major problem with any number of 'skeptic' theories. * His evidence (what there is of it) consists of extremely short "step" changes of sea surface temperatures - and as has been discussed here and elsewhere (as in the Escalator graphic), those are artifacts of noisy data and statistically insignificant short term trends. * Observed warming (25*10^22 Joules over the last 40 years in the top 2000 meters of the oceans) has occurred in a fairly steady rise. Not by "steps". * His statistics, if you can call them that, are terrible - he doesn't know enough to numerically support his hypotheses, and what he presents actually contradicts his ideas if you actually know what the numbers mean. --- In short, Tisdale's hypotheses consist of handwaving over statistically meaningless short periods and changes. None of it has been peer-reviewed, he is clearly not familiar with the body of peer-reviewed science and data on the issue, it's unsupported and unsupportable pixie dust. And it's rather frustrating to see such nonsense taken seriously by anyone, let alone be pushed repeatedly by Tisdale in his insulting and accusatory terms (multiple accusations of deception, conspiracy, data manipulation, etc). Hence the impatience from those who know anything about the ENSO and global warming...
  23. It's El Niño
    Presumably Tisdale shows that ENSO's influence has become far more extreme over the past few decades, that it is unleashing astounding quantities of formerly stored and hidden energy? Does he explain how that works? Or does the hypothesis only work if explained in isolation from other evidence? For instance, the overwhelming balance of evidence indicates that Arctic sea ice is going through area excursions and persistent volume loss in a way that's very unusual and likely not to have taken place for many thousands of years. For this to happen requires some input of additional heat energy to the Arctic Ocean and indeed other measurements confirm that's the case. Given the timeline of Arctic sea ice behavior, integrating these observations of sudden change with Tisdale's approach requires some mechanism that could sequester energy for many thousands of years and then suddenly release it. How does that work? As we all know, energy in the form of heat is very difficult to keep in one place. So what's the storage mechanism for Tisdale's energy?
  24. It's El Niño
    Kayell, I'm not paying good money to Tisdale to read his nonsense. Period. [snip] [Why do you think it is that no-one except for WUWT regulars are paying any attention to his theory?]
    Moderator Response: [Dikran Marsupial] Discussion of motivations snipped. Please lets just keep this to the science, and wait and see if Kayell can come back with a more substantive description of the argument.
  25. 2012 SkS Bi-Weekly News Roundup #1
    Another approach to the topic of Arctic methane than the one in the lead article above: http://www.facebook.com/photo.php?v=10151086189821330 Arctic Methane: Why The Sea Ice Matters With James Hansen, Natalia Shakhova, Peter Wadhams & David Wasdel... (Thanks to prokaryotes at RC for the link.)
  26. It's El Niño
    Wow, that was really quite an aggressive response, I must say. Where did that come from? You keep calling his ENSO argument 'crap' and 'nonsense'. And yet you admit you haven't actually read what he says, what his argument in full is all about. Sounds like pure reflexive dismissal to me. If this is such a nutcase piece of hypothesizing, then it should be exceedingly easy to actually show specifically where it fails. Your 1st law of thermodynamics counter-argument is of course only based in you not having read what he says of the matter. You know, I know and he knows where the energy is coming from. You know, I know and he knows how the Pacific uptake of solar energy varies wildly between La Niña and El Niño conditions.
    Moderator Response: [Dikran Marsupial] Please can EVERYBODY keep the discussion even tempered, or I will start deleting posts.

    Kayell: I suspect the tone of the reply was prompted by the rhetorical tone of your initial post "In my opinion, this site would not be complete without such an article. ". If you keep your posts purely scientific and avoid rhetoric you will find you get a much better response. If you want an argument addressed, then at least provide a link to where the argument is presented. If you know where the energy is coming from, then you ought to be in a position to debunk the argument yourself.
  27. It's El Niño
    Kayell, If any real people took Tisdale's argument seriously, then this site would tackle it. This site is not, however, required to tackle every bit of nonsense generated by every person on earth. The fact that Tisdale's cr@p gets play on WUWT is meaningless (and says a lot about WUWT and its readership). Those people are lost, and will stay lost. For what it's worth, however, Tisdale's entire collage of nonsense fails on one basic point, the First Law of Thermodynamics. From where does the energy come that allows ENSO to heat the planet? Put another way, ENSO has been around for thousands of years. Why, suddenly, now, does each successive El Nino warm the planet (which is actually the opposite, La Nina's warm the planet), while La Nina's have no counteracting effect? Why is heat suddenly accumulating now due to ENSO, yet never before today? What's changed? What is the physical mechanism at work? And before you ask, no, I haven't paid good money to read his cr@ppy theories, and I won't. If you'd like to send a PDF of his nonsense, and if I decide I'm willing to waste a chunk of my life looking at it, then it can maybe discussed (although, really, I'd rather spend my time looking at real science that is going to affect the course of policy, not sideline nutjobbery that is really of no consequence to anything). Short of that... no, I don't see the need for SkS to debunk every bit of Galilean look-at-me-I've-got-it-I'm-a-genius nonsense that exists in the world.
    Moderator Response: [Dikran Marsupial] Please keep the discussion to the science and avoid inflamatory terms, regardless of the perceived provocation.
  28. It's El Niño
    I would like to see an article where the ENSO argument of Bob Tisdale is being countered. The ENSO argument presented here is not the main skeptical argument on ENSO, after all. Tisdale is going further, claiming that the NINO3.4 index does not fully account for ENSO as a process. He purports to show that when the entire set of processes involved in the progression of the ENSO phenomenon is included, the ENSO IS able to explain global warming since the mid 70s. I would like to see you tackle HIS argument to show specifically where it fails. In my opinion, this site would not be complete without such an article.
  29. 2012 SkS Bi-Weekly News Roundup #1
    This article in Conversations by Stephan Lewandowsky is worth mentioning in this roundup. I haven't seen Stephan speaking so decidedly and loudly about the denialism yet. His scientific articles are opbviously toned as apropriate but the popular news does not need to be... And I think Stephan realy knows what he's talking about because he's been researching cognitive science for quite a while.
  30. What the 2012 US Election Means for Climate Change and Denial
    Re, my comment at 21? Stay tuned....I may well be changing my tune on my prior opinion of CD.o.
  31. 2012 SkS Bi-Weekly News Roundup #1
    BWTrainer @ 1 I agree with the spirit of your interpretation of Peak Oil as 'it is progressively becoming less economically feasible to use oil'. The peak originally referred to the greatest volume of production attainable with current technology, but it could also be the peak we allow to be produced, if we place a limit on our consumption in order to rein in AGW. Eventually, oil production/consumption will cease when the Energy Return On Energy Input (EROEI) equation approaches unity: when it takes the energy from a barrel of oil to recover a barrel of oil. Arriving at that point implies that we would have recovered/burnt all accessible oil in the meantime, which would only be possible under pretty much a business as usual scenario. Clearly, humanity needs to decide that it has a prudent limit to the amount of oil that should be recovered, irrespective of whether more could be recovered. In other words, we should decide that we have already recovered most of what the biosphere can absorb before tipping the climate and ocean acidity over the edge of an environmental cliff. I have a low opinion of humanity's proclivity to making wise choices, however. I rate our chances of making the prudent decision as very low. Our only hope is for some unforeseen calamity to befall the world's oil wells, terminating oil production. Without fossil oil to power mining operations, recovery of coal would also drop dramatically. At a stroke, this would eliminate the major drivers of AGW. The resulting food shortages and anarchy would kill off a good proportion of humanity as well, thus solving the over-population quandry at the same time. Failing the loss of oil supplies, I see little chance of us avoiding major changes to the climate, which will also result in food shortages and anarchy. If there is any intelligent life in space, now would be a good time for smart aliens to announce themselves and show us how to escape from the grave we are digging ourselves. But then, perhaps we are not worth saving.
  32. Fasullo and Trenberth Find Evidence in Clouds for High Climate Sensitivity
    Will … Thanks for your comments More recent work, eg. Reisinger et al (2011) suggests GWP for CH4 of ~86 this century and I think this value is broadly accepted. I was just being conservative by sticking with the IPCC value of 72. I agree with your analysis and concern about the adequacy of monitoring CH4 emissions and regional atmospheric concentration in the Arctic. Regarding emissions, I note that recent descriptions of plumes emerging from the East Antarctic Continental Shelf are based on reliable eye-witness accounts. I also note that Dr Shakhova and others have repeatedly called for improved, continuous monitoring of CH4 in the Arctic, particularly along the Russian coast. To-date, her calls in this regard appear to have been ignored, though I predict that as CH4 emissions increase, as they will, this will be rectified.
  33. 2012 SkS Bi-Weekly News Roundup #1
    One of the interesting issues with melting of the clathrates is how much will be solvated into the ocean, which is not saturated in methane. At 0 C, the solubility is about 0.04 g/kg water or, 0.04/16 moles, but there is a lot of water! Slow melting with currents bearing the saturated water away may not be so much of a problem.
  34. Dikran Marsupial at 03:41 AM on 17 November 2012
    It's a climate shift step function caused by natural cycles
    @sphaerica, yes, that is very nice way of explaining the issue as well!
  35. It's a climate shift step function caused by natural cycles
    Dikran, I personally like the John Nielsen-Gammon approach, illustrated in this animated GIF: If you use separate trend lines for El Nino, La Nina, and ENSO-neutral periods, there is clearly no step-change.
  36. 2012 SkS Bi-Weekly News Roundup #1
    I don't know that the idea of peak oil has "gone up in flames". Maybe I'm in the minority here, but I always interepreted it as 'it is progressively becoming less economically feasible to use oil'. After all, true "peak" oil was the point before humans took any of it out of the earth. Just because we've discovered more oil doesn't mean there is more oil. We've been drawing down a finite resource since day 1. What oil remains will be harder to extract than in decades past, so it will cost more to do so. And this doesn't even factor in the environmental costs that continue to mount and will hopefully become fully internalized in the price of oil. The price has been rising and will continue to rise until consumers are no longer willing to bear the burden.
  37. Dikran Marsupial at 02:40 AM on 17 November 2012
    It's a climate shift step function caused by natural cycles
    One way to show that the apparent step change is perhaps an optical illusion is to delete the 1998 El-Nino spike The data then resembles a steady rise at a more or less constant rate, with some variability superimposed on top. It certainly doesn't look like there has been a step change. The eye is easily fooled, which is why we have statistics.
  38. What the 2012 US Election Means for Climate Change and Denial
    "Speaking of Judith Curry, she has been included on a Dutch government initiative to get a 'full range of views' on climate science via...'Climatedialoge.org', where she has written her views on the decline of arctic sea ice." Indeed, and, like others here and elsewhere, I was concerned that CD.o would be just another lame attempt at 'false balance,' i.e., another Intertubes 'tone troll,' of sorts. Reading along with it, it seems not to be so much: Curry's assertions of "uncertainties abound" have been met with robust data, well-spoken and *decidedly* non-ad hominem comments, from real scientists in the matter. I have hope for CD.o!
  39. Fred Singer - not an American Thinker
    bahamamamma @12 - perhaps the difference you perceive is that Figure 8 is an 11-year running average.
  40. It's a climate shift step function caused by natural cycles
    Except for those trying to downplay the magnitude of climate change, I don't see a reason for trying to analyse the temperature record without first controlling for ENSO (at the very least). It's pretty hard to claim anything hopeful about the temp record once you start removing the noise. That's why JoNova et al like to play up how "little we know" about ENSO. ie because BOM was surprised by a turnaround in certain indices, FR2011 is suspect. I call that "drawing a long bow".
  41. It's a climate shift step function caused by natural cycles
    BillJ - "Some of his 'steps' had only 6 data points, so, although he may have got highly (statistically) significant 'steps' he probably used 'low' detection settings; and they were probably meaningless." That's actually the point - there have been various 'skeptic' claims of step changes in the climate, but those are just not supported by meaningful changes. They are often just statistically insignificant short term variations in the data driven by a system that has enough inertia to not be capable of such instant changes. Tamino was demonstrating (as you seem to have reinforced with your comments) that 'skeptic' claims of frequent short term step changes are not supportable. Your criticism is better applied to those unsupportable claims from the deniers. "There actually were steps in the series, in the 1940's; 1970's and around 1990's." Tamino has looked at this in his Changes post, and found significant changes around 1975, 1940, and 1920. There are not any such major changes in the 1990's - if you look at the trends since 1975, including the last 15 years results, if anything, in a higher trend than earlier in the period, from 1975 to 1997. Skeptic claims of a major change in the 1990's mostly appear to be short term insignificant trends starting from the El Nino in 1998 - see the discussion of this fallacy here. --- What I found astounding in all of these "step change" arguments is the apparent lack of physics behind them - the ocean heat content image above shows what's actually happening with the energy content of the Earth's climate, and that has an inertia that simply will not make sudden 90° turns. Shorter term changes in the atmospheric temperatures can (and do) occur, but those represent only a tiny fraction of the energy changes in the oceans - those changes are primarily driven by the ENSO and relatively small changes in ocean heat acceptance rates.
  42. We're heading into an ice age
    qwop, it never was about the absolute temperature. It's about the rate of change. Go back through the data and see how many periods you find that feature a 3C global temp increase over 300 years. You might check out the PETM event for starters. Of course, that event was 24x slower.
  43. 2012 SkS News Bulletin #4: Hurricane Sandy & Climate Change
    Interesting development about insurrance claims vs. classification. Big monies drive it, no doubt. And who should dig it to pay for the damages? Insurances, which will drive up the future re-insurance and premium rates, or the unlucky victims? Regaredeless of money, the storm deserves a classification of its own rather than simply hurricane, whatever it means for the claims is not important in the big picture emrging. The superstorm colliding with arctic cold front is something unprecedented in recent history. So the precedent requires new name. And still more like that is likely to come, as the warming continues.
  44. Dikran Marsupial at 21:02 PM on 16 November 2012
    It's a climate shift step function caused by natural cycles
    BillJ wrote "Step-changes can be created by random sequences" this is incorrect, random sequences can appear to have step changes in them, but that is not the same thing at all. Whether or not a time series actually does have a step change in them depends on whether there was a change in the physical process that generates the data. If not, the apparent step change is merely a meaningless artefact of random variation. The point of performing a test of statistical significance it to try and determine whether it is reasonable to believe that there has been a change in the underlying physical process, rather than the observations merely being an artefact of random chance. If a procedure detects step changes in randomly generated data, then that shows that the procedure is flawed and unreliable (the eyecronometer that is the most frequently used procedure is particularly bad in this respect). That is the point.
  45. The View from Germany: Tackling the real questions
    Related post by Peter Sinclair, 15. Nov: Germany’s Energiewende: Watching the Future Unfold
  46. We're heading into an ice age
    Depends on your definition of bad. Global sea level was many metres higher during the last interglacial, the Eemian, despite global temperatures being equivalent to either, the mid-twentieth century, or perhaps 1-2°C warmer than now. When one considers the amount of infrastructure put at risk by such a rise in sea level, I'd classify that as bad. And that is but one consequence of a future warmer world.
  47. It's a climate shift step function caused by natural cycles
    Bill, your remarks "probably meaningless" and "possibly none at all" are assertive without being demonstrative. Naturally they beg the response "don't just claim-- show us." Would you please do that?
  48. What the 2012 US Election Means for Climate Change and Denial
    Speaking of Judith Curry, she has been included on a Dutch government initiative to get a 'full range of views' on climate science via a website 'Climatedialoge.org', where she has written her views on the decline of arctic sea ice. Not surprisingly, she finds a lot of 'uncertainty' in the conclusions.
  49. We're heading into an ice age
    This is very interesting. In the past there were short and "very warm", but now we are in a semi long "warm" phase. According to the chart global temperatures were way higher in the past than they are now so the heat doesn't seem so bad compared to back then.
  50. There is no consensus
    Why do you say 95% in the intermediate response, when the basic says 97%, and your sources (Doran 2009, Anderegg 2010) both say 97%? Please be consistent with the message. "around 95% of active climate researchers actively publishing climate papers endorse the consensus position"

Prev  1027  1028  1029  1030  1031  1032  1033  1034  1035  1036  1037  1038  1039  1040  1041  1042  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us