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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.

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Comments 129601 to 129650:

  1. It's the sun
    "It is except for AGW, this is faith-based as there is not evidence. " "In parts of the Mesozoic it was not as hot but had higher levels of CO2, There is zero correlation." It isn't that black-and-white - less than perfect correlation is not zero correlation. From the physics, CO2 must have an effect; uncertainties are more from feedbacks; uncertainties are not infinite. Where there are variations that do not correlate, maybe there were other things happening at those times, such as (depending on time scale and magnitude of variations): biological evolution (such as evolution of land vegetation (albedo)), changes in geography (albedo, direct mechanical effects on atmospheric and oceanic circulations, direct thermal effects on atmosphere and ocean, interaction of thermal and circulation changes and other feedbacks). ----- HOW does O2 cause cooling? Effects on the ozone layer? Interesting, but I need some numbers... ------ "It is except for AGW, this is faith-based as there is not evidence. " By the standard you must use for evidence, there is likely no evidence for: millions of years of biological evolution by natural processes generating/sustaining the diversity of life and its interactions Pangea a sizable asteroid hit the Earth ~ 65 Ma by the Yucatan Peninsula the moon landings the (H word; yes, I'll play that card in this case, since I am able to lump it together with these others so that the defining characteristic of the group is not the offensiveness of denial) the expansion of the universe heavy elements are manufactured naturally in stars by nuclear reactions and in supernovae and maybe a few other related processes... ? the Earth is round (because if the space program was faked, then all we have to go on is...) ? quarks
  2. A broader view of sea level rise
    Ron Cram, It's not an ad hominen to reference a quote from the journal's editor: "I'm following my political agenda -- a bit, anyway. But isn't that the right of the editor?" I admire his honesty, but to answer his question: no - not if you want your journal to be respected. Rarely-cited sub-standard journals set up by like-minded skeptics don't carry much weight with the scientific community. It's no better than a self-published reference. What I do know is that the latest peer-reviewed research in the field now renders Loehle one of the last "ocean heat content cooling" holdouts.
  3. Volcanoes emit more CO2 than humans
    ps You don't see the increase because you are not looking hard enough. Everyone admits that it has increased and that is what the articles point out taken collectively. I have not included all because some are just so common place. It's pnly the recently become active (and recently discovered) that make the news.
  4. Volcanoes emit more CO2 than humans
    Re: "The only aspect I don't have an immediate issue with, is that there may be a link between changes in volcanic activity and changes in surface currents (e.g. ENSO)." That was the whole point. But it's not just ENSO. It's the same at every subduction zone where sea floor meets continent. They are all cyclic in nature and the cycles are not uniform. There are at least three major subduction zones in the arctic (there are more but not currently active and therefore not recognized as such but logic dictates their locations by direction of continental movement). And a rifting area at N. E. Greenland. Alaska is currently active. Not from westward movement as the subduction zone is in Asia but along the north continental edge of Alaska. These can be seen on a good quality seafloor floor. It looks like the Canadian Shield is turning clockwise.
  5. A broader view of sea level rise
    Ian, I was not aware of any recent problems so I appreciate you bringing this to my attention. As I read over the link you provided, it appears to be the same problem being discussed twice- a slow internal leak is causing false pressure readings. The first notice indicates a few floats will be greylisted as uncorrectable. For the others, adjustments will be made. The second notice discusses the fact newer floats seem to have this problem in greater numbers. They are working on a more reliable testing procedures but also working on a new style of pressure sensor from a different manufacturer. We will have to wait to see what impact the necessary adjustments will have on the data.
  6. A broader view of sea level rise
    NewYorkJ, I know the reputation of the editor of E&E. I also know E&E has published papers no other journal would publish only to have the findings published in E&E confirmed in subsequent AGU journal articles. One example is the M&M paper on the Hockey Stick. I also know the reputation of Craig Loehle, which is very good. Ad hominem attacks, against a journal's editor or the author of a paper, do not carry much weight with me. If you can find something wrong with Loehle's paper, then you would be doing real science. If you find something, let me know. David, land use/land cover changes can impact temperature as Roger Pielke and others have been pointing out for a long time. But the main impact of land use/land cover changes is not to CO2. If it was, the issue would be more warmly embraced by the IPCC and Roger would not be so adament that CO2 is not the only impact. Contrary to IPCC statements, no one really knows how much of the warming in the last quarter of the 20th century was natural and how much was from 50 years of accumulated anthropogenic CO2. It is a total fallacy to think a few PPMs of atmospheric CO2 in the last half of the 19th century is going to have a measurable impact on the atmosphere or ocean heat content or rising sea levels. You do know that atmospheric CO2 levels change naturally right? You do understand the carbon cycle?
  7. David Horton at 16:00 PM on 14 May 2009
    A broader view of sea level rise
    #13 Ron Cram. There is some evidence, and the proposition seems obvious, that from the time humans started altering the environment on a massive scale through agriculture they were having an impact on atmospheric chemistry. Up until that point, hunter-gatherer humans, like other animal species, were consuming plants that were replacing themselves, leaving CO2 in balance. Agriculture changes the equation by extensive land clearance and the build up of numbers of domestic animals. However the changes are still not likely to be great. It is only in the industrial revolution that we start extensively burning the locked up carbon in coal and oil. And sure, this process accelerates, but from the time it began we started to sow the seeds, unknowingly, of the accelerating disaster we have now. So picking a precise starting point for human effects is somewhat futile. Recognising the reality of the effect is essential.
  8. A broader view of sea level rise
    Ron Cram, Regarding point #2, keep in mind Energy & Environment is not at all a reputable scientific journal. It was set up by like-minded skeptics and is not carried by the ISI. The editor even has admitted to following a political agenda. http://en.wikipedia.org/wiki/Energy_and_Environment
  9. A broader view of sea level rise
    Chris, 1. I'm sorry. I misread you. Now I see what you are saying. However, the real warming happened from 1975-2000, not from 1950. According to Labitzke of UCAR, about one-third of warming from that period was solar. Based on the conclusion of his presentation, solar did increase during this period. That was why I misread you. I was certain you were familiar with this commonly held opinion. http://cedarweb.hao.ucar.edu/workshop/tutorials/2001/Labitzke.pdf 2. The amount of data needed depends on the quality of the data and the physical theories in play. Yes, we can conclude that heat uptake by the oceans has stopped based on Argo data. BTW, one of the reasons I like Argo data is that it is freely available to everyone and therefore less susceptible to arbitrary and unexplained adjustments. Craig Loehle recently updated the Willis study with the latest data and guess what? It shows more pronounced cooling of the oceans. You can download the Loehle paper at http://www.ncasi.org/publications/Detail.aspx?id=3152 3. BTW, Loehle points out some reasons to be skeptical of the Argo data. 4. Where are you getting your numbers for CO2? Have you looked at the amount of human emitted CO2? It is extremely minimal. Any change in atmospheric CO2 during these early periods had more to do with the natural carbon cycle than any human contribution.
  10. Volcanoes emit more CO2 than humans
    Quietman I've tried wading through the 9 pages of comments, and my conclusions so far are: * not a single article you've linked to says what you think it says; none of them certainly support your ideas. * "geologically fast" is still orders of magnitude longer than a human life-span. * You do not understand the magnitude of the global Thermohaline circulation; it will probably overpower the effects of just about all the heat supplied by submarine magmas, and it will certainly smooth out any short term changes in heat supply. * there does not appear to be any evidence that tectonic and volcanic activity are significantly on the rise globally * the significance of planetary alignments on the earth has been falsified conclusively as nothing more than woo; and as soon as someone asserts they understand the fundamental forces of nature better than all the specialists put together, red flags go up anyway The only aspect I don't have an immediate issue with, is that there may be a link between changes in volcanic activity and changes in surface currents (e.g. ENSO).
  11. It's the sun
    ps see "Global warming and natural climate change in the past" This discussion does not belong in this thread.
  12. It's the sun
    not exposed to the air s/b now exposed to the air (refer to the paleomaps)
  13. It's the sun
    Re: "and science is nothing if not evidence-based." It is except for AGW, this is faith-based as there is not evidence. Re: "The peak of the Eocene was perhaps 6 oC warmer than now. Atmospheric CO2 levels were as high as 1500 ppm." In parts of the Mesozoic it was not as hot but had higher levels of CO2, There is zero correlation. Re: "Likewise the warming of the Eocene is linked to high atmospheric CO2 levels and cooling towards the late Oligocene was sequentially reduced CO2 levels." No it's increased O2 caused cooling, not reduction of CO2. One is a cause and the other is a consequent. Re: "We might account for 100 or even 200 ppm of atmospheric CO2 that way, but we're more than 1000 ppm of atmospheric CO2 out. CO2 levels can't have risen in the manner that you suggest - it's incompatible with the evidence." No, it's not when you take into account the massive increase in tectonic activity and bombardment from space of asteroids and comets (from about 70mya through the Miocene). Think just a minute of how much NOx and Methane was being released from former seabeds not exposed to the air.
  14. Arctic sea ice melt - natural or man-made?
    I've now read it. I still don't know what you mean...
  15. Arctic sea ice melt - natural or man-made?
    Re 517 - I haven't gotten around to reading it yet; not sure what you mean...
  16. It's the sun
    Re 359 - when we say that it is only about 0.1 W/m2 (and, actually, I think that's rounded up from maybe 0.08 W/m2), we - here I am assuming what others mean - we don't mean that it is always exactly the same. But it cannot vary much very fast on large (regional and global) scales because much of the heat near the surface had to come from below, etc... a sudden increase in the heat flux would deplete the near-surface heat and it would take time for heat from below to build up the near-surface heat to a point where it can flow out at the same rate... and of course, the rate of radioactive decay within the crust is basically set in stone once the stone forms. Larger changes have to take millions of years... and there are negative feedbacks that would keep it from getting much larger or much smaller than what it would be following a billions-of-years long cooling trend. Re 363 - why, then, should you assume that changes in geothermal heat fluxes and continental arrangements should have any effect? - even though the later obviously and easily could, it would be an assumption (that certain physical laws held for other time periods, etc.) that it ever did... (Of course it (changes in geography) did, and of course CO2 did, etc.)
  17. It's the sun
    re: #361. The PETM obviously didn't have "zero duration". The greenhouse-induced warming took up to 20,000 years with a longer recovery time. It produced a large temperature rise, ocean acidification, and is associated with expulsion of a very large amount of 13C-depeleted carbon into the atmosphere (and oceans). It caused very significant extinctions of marine organisms. #363/364: The science is speaking for itself Quietman, based on careful assesment of evidence....and science is nothing if not evidence-based. The fact is that the PETM is associated with very high atmospheric CO2 levels, and these were 13C-depleted (possibly originating in methane clathrates), and the oceans acidified. These are all characteristics of warming from greenhouse forcing and CO2 uptake by the oceans. Likewise the warming of the Eocene is linked to high atmospheric CO2 levels and cooling towards the late Oligocene was sequentially reduced CO2 levels. We can be scientific and assess the relationship between raised/reduced temperatures and raised/reduced CO2 durng these periods. We can inspect the ice age transitions and observe that the glacial-interglacial transitions were generally associated with a temperature rise of 5-6 oC and raised CO2 of around 90 ppm (180-270 ppm through several of the transitions in the ice core record). Thus a global temperature rise/fall of around 1 oC recruits/sequesters around 15 ppm of CO2 into/from the atmosphere. The peak of the Eocene was perhaps 6 oC warmer than now. Atmospheric CO2 levels were as high as 1500 ppm. It's immediately obvious that such high CO2 levels cannot be due to the physicochemical equilibrium between atmospheric and oceanic CO2 that was responsible for temperature-linked CO2 changes during ice age glacial-interglacial transitions. We might account for 100 or even 200 ppm of atmospheric CO2 that way, but we're more than 1000 ppm of atmospheric CO2 out. CO2 levels can't have risen in the manner that you suggest - it's incompatible with the evidence. And of course the notion that CO2 follows temperature but not the other way round is logically flawed. Any phenomenon/event that releases large amounts of greenhouse gas into the atmosphere must cause the Earth to warm. The Earth warmed rather quickly during the PETM as a result of the massive enhancement of greenhouse gases that has left multiple traces in the sedimentary record. That's what the evidence shows.
  18. A broader view of sea level rise
    for John Cook re my post #9. Sorry for calling you John Cross...I did get it right once in my post! If you want to edit my post and delete this one, you could tidy up my mistake... while I'm acknowledging/confessing my posting errors, I inadvertently failed to close a "blockquote" in a recent post on the volcanoes thread: http://www.skepticalscience.com/argument.php?p=9&t=221&&a=28 and that seems to have been carried through subsequent posts! I usually save my long posts with markups as a .htm for viewing in a web browser to chack that it's all O.K., but an unclosed "blockquote" right at the end of a message doesn't show up!
  19. A broader view of sea level rise
    Re #12 1. Ron, I'm not claiming anything of the sort. Can you clarify where you got that idea?! I pointed out that the evidence indicates the solar cycle results in a surface temperature response of around 0.1 oC of cooling max to min, and obviously 0.1 oC of warming min to max. I pointed out that there has been no warming trend in the solar irradiance since the late 1950's...if anything all measures of solar parameters indicates a small cooling solar contribution during the last two decades. There was very likely a small solar contribution to warming in the early part of the 20th century (1900's-1940's). 2. Well yes. 4-5 years is an extremely small time period in this context. It's not surprising that there are large uncertainty ranges in the measurements...however one cannot cherrypick extrema from uncertainty ranges! The bottom line is that the ocean heat/sea level rise "budget" seems to have been "closed" by analyses published in a couple of papers earlier this year (see my post #7 and papers cited there). The evidence indicates that there has been a steric (warming) contribution to sea level rise during this period. Thus one cannot conclude that heat uptake by the oceans has stopped since 2003, since the evidence indicates that it hasn't. Obviously we'll have a clearer picture (less uncertainty) as time progresses. 3. Fair enough. Unless additional errors appear in the Argo data one may as well assume that the Argo output is accurate. There may or may not be an inconsistency in the Argo data compared to the sea level-mass-steric analysis. 4. Atmospheric CO2 levels rose from ~ 286 ppm - 297 ppm in the period 1850-1900, and from ~300 ppm to 309 ppm from 1910-1940 (the two periods you specified) [see ref. [***} in my post #9]. Within a climate sensitivity of 3 oC of surface warming per doubling of atmospheric CO2 concentration, this should yield warmings near 0.15 oC and 0.13oC, respectively. So the CO2 rise most likely did contribute to warming (and sea level rise) during these periods. Of course no one is suggesting that raised CO2 was the sole cause of warming during these periods. It's likely that there was a solar contribution to warming at least during the period 1910-1940; some of the warming during this period was also due to recovery from high volcanic activity (aerosolic cooling).
  20. Ian Forrester at 01:11 AM on 14 May 2009
    A broader view of sea level rise
    Ron Cram said: "1. So you are claiming changes to solar irradiance can cause cooling but not warming? The solar physicists I know will be very surprised to hear that!" Re-read what Chris said. He said that the drop from maximum to minimum was 0.1 degrees C. Funny that you should completely misinterpret that to "can only cause cooling." Also there are at least two other problems identified in the ARGO system besides the one you mention. See: http://www.argo.ucsd.edu/index.html
  21. A broader view of sea level rise
    David, my comment was linked more to industrial emissions of CO2 than to any historical debate about when the industrial period began. Look up CO2 emissions from 1850 to 1900 and you will see they were miniscule compared to emissions in the last half of the 20th century or compared to natural changes to atmospheric CO2 from the carbon cycle. There is no way CO2 can be blamed for sea level rise during the years 1850-1900.
  22. A broader view of sea level rise
    Chris, 1. So you are claiming changes to solar irradiance can cause cooling but not warming? The solar physicists I know will be very surprised to hear that! 2. My comment was intended to point out the error bars were nearly as large as the supposed change. Anytime I see that I have to become skeptical of any real change, especially when other scientists have already published saying there has been no significant warming. 3. The Argo data is far and away the best observation network we have for the climate system right now. The surface observation system is confounded with many problems, the greatest being the fact it is looking at atmosphere and not ocean storage of heat. Your dismissal of the Argo network because you don't like the data is troubling to me and should be troubling to you. The Argo technology is not that new. The instruments that measure temperature and salinity are very precise and reliable. The only problem the floats had were with the fall rate, so that the numbers being reported were thought to come from a different ocean depth. I do not know anything about the methods of L&W or the other papers you cited, but I do know about the Argo network which began deployment back in 2000. Argo has had global coverage since 2003, take very precise measures and now we know about the potential for fall rate error so it is being watched very carefully. 4. Regarding pre-industrial sea level rise, take a look at any chart of CO2 emissions. Very, very little CO2 was emitted from 1850 to 1900. In fact, CO2 emissions did not really kick in until 1950. CO2 rise cannot explain the increase in global temps from 1910 to 1942.
  23. A broader view of sea level rise
    David Horton, You could even go back a little further than this and link anthropogenic influences to LIA cooling. http://news.bbc.co.uk/1/hi/sci/tech/4755328.stm http://news-service.stanford.edu/news/2009/january7/manvleaf-010709.html ...although others believe natural influences (solar, volcanic) are the key drivers of the few tenths of a degree of global mean temperature change during that period. Regardless, recent warming has been very rapid. http://www.realclimate.org/index.php/archives/2008/09/progress-in-millennial-reconstructions/
  24. Are sea levels rising?
    It's interesting to note that the jump leading into 1998 doesn't lessen due to the Inverse Barometer correction. Likely that jump was largely a result of thermal expansion as ocean temperatures shot up well above the trendline due to the super el Nino. Oceans have had slight cooling in recent years, largely as a result of ENSO values turning negative, yet sea levels continue to rise, indicating perhaps that land ice melt is accelerating. The next moderately strong el Nino could bring a sizable jump.
  25. Are sea levels rising?
    "I have seen the 2mm/year assumption in a lot of places including in the IPCC report of course there listed as 15-20 cm per century. I agree the 6 to 10 meter claims are rediculous! But maybe you better tell Al Gore. The claim in AIG is 20 feet." Common error. AIT doesn't put any timeframe on 20 feet of sea level rise. [I see John Cross already covered this] One could say Gore is being cautious. If you read the latest draft SCAR report, 6 meters is seen as an upper bound by 2100: "Rates of sea level rise at least twenty times the current 3.1 mm/yr sustained over more than a century have been measured for the transition to the current warm period following the termination of the last ice age and during some of the warmer intervals of the last ice age. Until improved predictive capability is achieved, this can be regarded as a reasonable upper bound of Antarctica's potential contribution to global sea level. This maximum rate (62 mm/yr) would lead to a 6-meter sea level rise by 2100, but such rates occurred when there was considerably more ice on the planet." http://www.antarctica.ac.uk/met/SCAR_ssg_ps/ACCE.htm
  26. How to cherry pick your way to Antarctic land ice gain
    "The article then transitions into a discussion of sea ice so smoothly, you barely even notice they're no longer talking about land ice." Yep. This confusion seems deliberate by the author. And it's land ice that has the implication for sea level rise. Also, here's more interesting spin from the Australian article: "Last week, federal Environment Minister Peter Garrett said experts predicted sea level rises of up to 6m from Antarctic melting by 2100, but the worst case scenario foreshadowed by the SCAR report was a 1.25m rise." A potential contribution of 1.25 m of sea level rise by 2100 from just Antarctic ice sheets is big news, yet the author here is downplaying it by comparing it to quotes (or misquotes in this case) by a politician. An excellent debunking of this trashy piece from the mainstream media can be found here: http://scienceblogs.com/deltoid/2009/05/the_australians_war_on_science_38.php Fran Kelly: Today, some positive news. Rather than melting, the science shows that ice is expanding in much of Antarctica and that in parts is getting thicker. ... Ian Allison: We have now new evidence that confirms that on average we are losing ice from both Greenland and Antarctica which is contributing to sea level ... Kelly: ... but you found something that suggests its perhaps not as rapid a melt as we once thought. Can you tell us about what you've found, the difference in the East and West in Antarctica. Allison: ... In East Antarctica there might be a slight increase due to increased snowfall. ... on average West Antarctica is losing more ice that the East is gaining
  27. Volcanoes emit more CO2 than humans
    ps Here's the latest in an ever growing string: "The volcanoes in the central African nation could be about to erupt, threatening Goma, which has a population of more than half a million people, scientists said Thursday. They made their observations on visits to the two volcanic peaks of Nyiragongo and Nyamulagira." - MSNBC Science News
  28. Climate's changed before
    Here is something that you should know already: The Paleogene Period of the Cenozoic Era: 65.5 to 23.0 million years ago The Paleocene (“ancient recent life”) epoch marks the beginning of the Paleogene Period and the Cenozoic era. The sea-level fell to expose dry land in much of inland North America, Africa, and Australia. South America however was cut adrift with its own unique evolving “ark” of birds, mammals, and reptiles. The Paleocene Epoch of the Paleogene Period: 65.5 to 55.8 million years ago The rifting of the North Atlantic cut off North America from Europe, and South America lost links with Antarctica. India and Scotland were home to mountain-building episodes. The sea-level rose and seas invaded much of Africa, Australia, and Siberia. Climates were generally warm or mild worldwide. Tropical palms flourished as far north as the London Basin. The unusual mixture of tropical and subtropical elements in the northern latitudes in the Eocene suggests that the mean annual temperature of these regions was not as high as in the present tropics, but that the flora was maintained by a greater rainfall than occurs in these northern latitudes today, with no pronounced seasonality in its distribution, and by the absence of winter frost. The Eocene Epoch of the Paleogene Period: 38-54 million years ago There was an increase in volcanic activity, and plate tectonic movement, as India collided with Asia. The last remnant of the supercontinent of Gondwanaland broke up as Australia and South America both separated from Antarctica The Oligocene also marked the start of a generalized cooling, with glaciers forming in Antarctica for the first time during the Cenozoic. The increase in ice sheets led to a fall in sea level. The tropics diminished, giving way to cooler woodlands and grasslands. Although there was a slight warming period in the late Oligocene, the overall cooling trend was to continue, culminating in the Ice Ages of the Pleistocene. The Oligocene Epoch of the Paleogene Period: 33.9 to 23.0 million years ago Source: Palæos
  29. Climate's changed before
    Chris Your examples are results of modern education just like these: "This finding has opened new doors in dinosaur research on this part of the continent: "It established that dinosaurs were nesting at this high latitude," said Miyashita. " Science Daily or Live Science "Some dinosaurs (warm-blooded, perhaps) were surprisingly good at withstanding near-freezing temperatures, they say. Witness the team's latest find, a diverse stash of dinosaur fossils laid down just a few million years before the big impact, along what's now the Kakanaut River of northeastern Russia. Even accounting for continental drift, the dinos lived at more than 70 degrees of latitude north, well above the Arctic Circle. " There is no excuse for this poor education. This started in the late 1960s with the long hairs and just went downwards since then.
  30. It's the sun
    ps Ice cores have already proven that CO2 follows temps, not the other way around. This means that regardless of how much CO2 there was, it is irrelevant. It was NOT the cause and only confirms that CO2 increases with increased temperatures some time afterward, that's all.
  31. It's the sun
    Patrick by "blowing smoke" I mean bad science procedures. They assume AGW and try to make the past fit the hypothesis rather than study of the period and let the science speak for itself WITHOUT ASSUMPTIONS.
  32. It's the sun
    had to lasting s/b had no lasting
  33. It's the sun
    Chris The PETM is a spike of zero duration in geologic time. It represents an event that caused a heat peak but not a continued warming as it immediately cooled. The cause of this spike is unknown and as it had to lasting effect is irrelevant. The later climb represents changes in ocean currents in direct response to the Med being cut off from the Pacific.
  34. It's the sun
    Patrick It would be interesting if true, however they are blowing smoke.
  35. It's the sun
    "The geothermal flux is just too small (around 0.1 W/m2 compared to the greenhouse-augmented solar flux absorbed by the Earth’s surface of over 150 W/m2). " Yes and the continents are fixed. This is an old story that isn't true. It is not a constant but a variable.
  36. Volcanoes emit more CO2 than humans
    ginckgo "The term thermohaline circulation (THC) refers to the part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes." This is the wiki definition. It's incomplete, but close. What part do you not understand?
  37. David Horton at 10:50 AM on 13 May 2009
    A broader view of sea level rise
    Ron Cram "The mid-19th century was during the pre-industrial period" is simply not true. The industrial revolution got under way in the middle of the eighteenth century (and arguably could even be traced back to about 1700) and was in full swing by the mid nineteenth. There was then a "second industrial revolution' from about 1880 to 1914 as the technological developments of the first part of the industrial revolution allowed the start of all kinds of new industries. So if you want to look at human contributions to global warming you need to look a long way back. And then observe the acceleration of industrial production as time went by.
  38. It's the ocean
    [In 2005 James Hansen, Josh Willis, and Gavin Schmidt of NASA coauthored a significant article (in collaboration with twelve other scientists), on the “Earth’s Energy Imbalance: Confirmation and Implications” (Science, 3 June 2005, 1431-35). This paper affirmed the critical role of ocean heat as a robust metric for AGW. “Confirmation of the planetary energy imbalance,” they maintained, “can be obtained by measuring the heat content of the ocean, which must be the principal reservoir for excess energy” (1432). ... In 2007 Roger Pielke, Sr. suggested that ocean heat should be used not just to monitor the energy imbalance in the climate system, but as a “litmus test” for falsifying the IPCC’s AGW hypothesis (Pielke, “A Litmus Test…”, climatesci.org, April 4, 2007). Dr. Pielke is a Senior Research Scientist in CIRES (Cooperative Institute for Research in Environmental Sciences), at the University of Colorado in Boulder, and Professor Emeritus of the Department of Atmospheric Science, Colorado State University, Fort Collins. One of the world’s foremost atmospheric scientists, he has published nearly 350 papers in peer-reviewed journals, 50 chapters in books, and co-edited 9 books.] The Global Warming Hypothesis and Ocean Heat I think that this was an excellent point.
  39. Climate's changed before
    ps Volcanos actually causing ENSO is far fetched and yes a bit silly. It's what happens on the ocean floor near the subduction zone where the driver for ENSO resides.
  40. Climate's changed before
    ginckgo Sorry, that was posted for Patrick who was up to speed on vulcanism. The Volcanos thread has the argument presented with links to recent articles explaining the background. I am missing one reference about ENSO and I can't find it again to post a link. When I do it will also be posted in the Volcano thread. John wants us to keep the subject relevance when we can. From your statement I think you have some reading to catch up on. :)
  41. Arctic sea ice melt - natural or man-made?
    Patrick Considering that was a pro-AGW article in the "call for actions" for the greens columns, you don't seem very receptive.
  42. A broader view of sea level rise
    re #9 1. solar irradiance. Ron you are mistaking the longish term trend in solar irradiance (which shows no net warming contribution at least since the mid 20th century and a small cooling contribution during the last couple of decades [*]), and the contribution from the solar cycle. Several analyses indicate that the peak to minimum solar cycle contributes of the order of 0.1 oC of cooling to the Earth's surface temperature (e.g. [**]). In a world warming under a greenhouse-induced radiative imbalance, at around 0.15 oC per decade, we expect the solar cycle cooling to "overpower" the greenhouse induced warming during the downturn (cooling) part of the cycle. Of course in the real world the solar cycle contribution is difficult to pull out since stochastic variation in the climate system (El Nino’s, volcanoes, cloud cover variation and such-like) generally masks the small solar cycle contribution in the surface temperature record. At present, since the solar minimum we’re currently in is somewhat prolonged we’re likely getting the full cooling “whack” from that. 2. steric (warming) contribution to sea level rise. You can’t take the minimum in an uncertainty range and base any conclusions on that whatsoever. After all one could use your “strategy” and state that the steric contribution to sea level rise is as much as 2.5 mm per year! Four years is an extremely short period of time in this context, and reduction in uncertainties requires longer analyses, certainly so if one is attempting to make fundamental, all-encompassing conclusions as you are. 3. As the recent papers I cited show, the evidence indicates there is a steric (warming) contribution to sea level rise during the last few years. That’s not necessarily incompatible with the Argo float data which shows a rather small steric contribution to sea level rise during this period. Perhaps some of the heat has penetrated somewhat more deeply into the oceans. Perhaps some of the Argo data is still flawed. This is a very new technology, and only 18 months ago it was shown that a problem with the Argo data was fooling everyone into thinking that the oceans were cooling: http://earthobservatory.nasa.gov/IOTD/view.php?id=35805 http://earthobservatory.nasa.gov/Features/OceanCooling/ as you said in your post #1 in reference to sea level rise and heat content: “If data shows one going up and one going down, they may have an error in their data somewhere. Within certain margins of error, this data has to correlate”. Exactly so. However the recent papers (see my post #7) seem to have reconciled any dichotomy. Sea levels have risen during the period 2004-2008. Some of this is due to ocean warming (steric) and some (likely more) due to increased ocean mass (land ice melt). Just as one cannot pick arbitrary extrema in uncertainty ranges to try to make a point, nor can one arbitrarily make a personal selection of which of two opposing data sets are correct under circumstances where there is uncertainty. After all the (short!) history of the Argo floats would tend to indicate that it’s more likely that any error (if there is an error) lies there. And we should reemphasise that we are dealing with extremely short periods of analyses! 4. pre-industrial sea level rise The evidence indicates that sea levels didn’t rise significantly during the millennium before the mid/late 19th century (see paper [***] in post #7). The notion that sea level rise is due to recovery from the Little Ice Age doesn’t make much sense in the context of the sea level record. After all, if any cooling forcings pertaining to the LIA were removed, the sea level rise would occur initially with a rapid rate that would decrease as the “recovery” was approached. The record (see John Cross’s figure 1 above) shows the opposite. In any case the “recovery” from the LIA was pretty much complete by the early/mid 19th century: http://en.wikipedia.org/wiki/Little_Ice_Age http://en.wikipedia.org/wiki/File:Sunspot_Numbers.png You specifically suggested (your post #1) that sea levels should “rise at a rate much greater than the natural rates seen during the non-industrialized years”. The evidence indicates that is the case, at least as far as net sea level rises are concerned. There was no significant net change in sea level (as far as we can tell) during the millennium (at least) before the mid-19th century (see my post #7); sea levels rose very slowly from the late 19th century (see John Cook’s fig. 1 above), and the rate of increase has accelerated through the mid-late 20th century. And although the early release of CO2 from fossil fuel use (and land clearance) was smallish in the late 18th/early 19th century, it was quite significant (atmospheric CO2 levels rose from 277 – 286 ppm in the period from the late 18th to mid 19th century [***], and this should have produced a small warming (0.1 oC within a climate sensitivity of 3 oC per doubling of atmospheric CO2). So the initial rise in sea level could indeed “be attributed to anthropogenic CO2”. Maybe it wasn’t of course. But you are making strong assertions that are either contradicted by straightforward evidence, or are only compatible with the arbitrary selection of extrema in ranges of uncertainties. [*] Lockwood M and, Frohlich C (2008) Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature. II. Different reconstructions of the total solar irradiance variation and dependence on response time scale Proc. Roy. Soc. A 464, 1367-1385. abstract: We have previously placed the solar contribution to recent global warming in context using observations and without recourse to climate models. It was shown that all solar forcings of climate have declined since 1987. The present paper extends that analysis to include the effects of the various time constants with which the Earth's climate system might react to solar forcing. The solar input waveform over the past 100 years is defined using observed and inferred galactic cosmic ray fluxes, valid for either a direct effect of cosmic rays on climate or an effect via their known correlation with total solar irradiance (TSI), or for a combination of the two. The implications, and the relative merits, of the various TSI composite data series are discussed and independent tests reveal that the PMOD composite used in our previous paper is the most realistic. Use of the ACRIM composite, which shows a rise in TSI over recent decades, is shown to be inconsistent with most published evidence for solar influences on pre-industrial climate. The conclusions of our previous paper, that solar forcing has declined over the past 20 years while surface air temperatures have continued to rise, are shown to apply for the full range of potential time constants for the climate response to the variations in the solar forcings. [**]J. L. Lean and D. H. Rind (2008) How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006 Geophys. Res. Lett. 35, L18701. This isn’t stated in the abstract, but the analysis indicates a solar cycle (max-min) surface temperature change of 0.11 oC with a one month lag. [***]D. M. Etheridge et al (1996) "Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn J. Geophys Res. 101, 4115 -4128.
    Response: It's a common mistake but my name is John Cook, not John Cross :-)
  43. Wondering Aloud at 06:49 AM on 13 May 2009
    Are sea levels rising?
    Sorry John Thanks for the correction AIG? What the heck? simple typo. I do that a lot. I think the implication in AIT is that this is a likely near term consequence. I know you can find proponents trying to scare us with it being a near term thing. It is mighty hard for people to get frightened over something that might happen hundreds if not thousands of years in the future. Please expand on fractal sketicism. Explain, sounds like fun.
  44. A broader view of sea level rise
    Chris, I can appreciate the quote in the L&W paper: "we find that the sum of steric sea level and the ocean mass component has a trend of 1.5 +/- 1.0 mm/a over the period, in agreement with the total sea level rise observed by either Jason-1 (2.4 +/- 1.1 mm/a) or Envisat (2.7 +/- 1.5 mm/a) within a 95% confidence interval." In other words, the steric rise could be as little as 0.5mm/a over a multiyear period and some portion of this is due to salinity changes. I don't see how this is any different than the finding by Josh Willis that there has been no increase in ocean heat content since 2003. If one understands the impact of "0.85 ± 0.15 watts per square meter" radiative impact spoken of by Hansen, you would expect a much greater than observed warming. If you have been following the debates on total solar irradiance, you will note that changes in solar irradiance are said to be trivial. The lack of ocean heating cannot be traced to solar minimum, at least not by AGW alarmists. Regarding sea level rise centuries ago, yes, you would expect sea level to rise as the planet is coming out of the Little Ice Age. The mid-19th century was during the pre-industrial period and the beginning of sea level rise cannot be attributed to anthropogenic CO2. Regarding the amount of data needed for analysis, scientists will always prefer more data to less and they should. That does not mean that we do not have enough data now to seriously question the theory of AGW and to begin searching for ways the theory may need to be modified. To restate: It is not possible for an anthropogenically caused radiative imbalance of 0.85 ± 0.15 watts per square meter not to show up in warming oceans year over year over year without some observable intervention such as a major volcano. I just do not see how anyone can argue with that very basic observation.
  45. A broader view of sea level rise
    re #1: Ron, I think we can get too carried away with analyses over very short periods, and it’s an excellent idea of John’s to expand his analysis of sea level rise with a historical perspective. However going back to the recent period, the absence of warming in the upper oceans during the last five years can’t really be taken as evidence that our understanding of the effects of enhanced greenhouse gas concentrations is flawed, and it’s certainly not true that “If AGW theory is true ocean heat content and sea level would rise uninterrupted year over year over year.” As for your additional comment that “it would rise at a rate much greater than the natural rates seen during the non-industrialized years.”, the evidence is actually consistent with that assertion . There are a number of points: 1. Global warming theory (that enhanced greenhouse gas levels results in an enhanced global surface temperature at equilibrium, somewhere in the region of 2-4.5 oC per doubling of atmospheric CO2) certainly doesn’t require an uninterrupted rise in heat content/sea level. Obviously one can have periods where the radiative forcing in a warming world is temporally static or reduced (say the few years during which the insolation drops towards the solar minimum such that it opposes the small enhanced greenhouse warming for this period). We might well find no heat uptake by the oceans, and no warming during this period. During the solar “upswing” towards the solar maximum, enhanced insolation will reinforce (rather than oppose) slowly rising greenhouse forcing. 2. The other question is whether heat uptake by the oceans really has stopped during 2003. That conclusion/assumption is actually not fully consistent with the evidence. It’s correct that there has been little heat uptake in the upper (700 metres) of the ocean as measured by Argo floats. However if one considers the ocean heat budget in the manner that you suggest in your post (i.e. the steric, warmth-induced sea level rise and mass rise from land ice melt should be consistent with measured sea level rise determined from satellites), the most recent analyses indicate that there has been some enhanced steric (heat uptake) contribution to sea level rise during the last five years (see references below [*, **]. These papers indicate that 15% (Cazenave) or 40-50% (Leuliette and Miller) of the sea level rise in the period 2004-2008 is steric (i.e. due to heat uptake). 3. Obviously these are very short periods of measurement/analysis. We certainly don’t expect an uninterrupted rise in sea level, and a 4-5 year period with no steric contribution to sea level rise (i.e. due to heat uptake) isn’t unexpected. However that actually seems not to be the case. The oceans likely have absorbed heat during the last 5 years. Obviously even if there is no net heat uptake due to a temporary balance of radiative forcing, we expect the sea level to continue to rise due to mass uptake from melting land ice in a warm world… 4. John Cross has shown that the evidence indicates sea level rise has accelerated since the mid/late 19th century. During at least the 1000 before the mid 19th century, and likely for a further millennium before that, the evidence indicates that there was little if any net sea level rise [***]. [*]Cazenave A et al. (2009) Sea level budget over 2003-2008: A reevaluation from GRACE space gravimetry, satellite altimetry and Argo Glob. Planet. Change 65, 83-88. abstract: From the IPCC 4th Assessment Report published in 2007, ocean thermal expansion contributed by similar to 50% to the 3.1 mm/yr observed global mean sea level rise during the 1993-2003 decade, the remaining rate of rise being essentially explained by shrinking of land ice. Recently published results suggest that since about 2003, ocean thermal expansion change, based on the newly deployed Argo system, is showing a plateau while sea level is still rising, although at a reduced rate (similar to 2.5 mm/yr). Using space gravimetry observations from GRACE, we show that recent years sea level rise can be mostly explained by an increase of the mass of the oceans. Estimating GRACE-based ice sheet mass balance and using published estimates for glaciers melting, we further show that ocean mass increase since 2003 results by about half from an enhanced contribution of the polar ice sheets - compared to the previous decade - and half from mountain glaciers melting. Taking also into account the small GRACE-based contribution from continental waters (<0.2 mm/yr), we find a total ocean mass contribution of similar to 2 mm/yr over 2003-2008. Such a value represents similar to 80% of the altimetry-based rate of sea level rise over that period. We next estimate the steric sea level (i.e., ocean thermal expansion plus salinity effects) contribution from: (1) the difference between altimetry-based sea level and ocean mass change and (2) Argo data. Inferred steric sea level rate from (1) (similar to 0.3 mm/yr over 2003-2008) agrees well with the Argo-based value also estimated here (0.37 mm/yr over 2004-2008). Furthermore, the sea level budget approach presented in this study allows us to constrain independent estimates of the Glacial Isostatic Adjustment (GIA) correction applied to GRACE-based ocean and ice sheet mass changes, as well as of glaciers melting. Values for the CIA correction and glacier contribution needed to close the sea level budget and explain GRACE-based mass estimates over the recent years agree well with totally independent determinations. [**] Leuliette EW and Miller L.(2009) Closing the sea level rise budget with altimetry, Argo, and GRACE Geophys Res. Lett. 36, art # L0406 abstract: An analysis of the steric and ocean mass components of sea level shows that the sea level rise budget for the period January 2004 to December 2007 can be closed. Using corrected and verified Jason-1 and Envisat altimetry observations of total sea level, upper ocean steric sea level from the Argo array, and ocean mass variations inferred from GRACE gravity mission observations, we find that the sum of steric sea level and the ocean mass component has a trend of 1.5 +/- 1.0 mm/a over the period, in agreement with the total sea level rise observed by either Jason-1 (2.4 +/- 1.1 mm/a) or Envisat (2.7 +/- 1.5 mm/a) within a 95% confidence interval. [***]Church JA et al. (2008) Understanding global sea levels: past, present and future. Sustainability Science 3, 9-22 . abstract: The coastal zone has changed profoundly during the 20th century and, as a result, society is becoming increasingly vulnerable to the impact of sea-level rise and variability. This demands improved understanding to facilitate appropriate planning to minimise potential losses. With this in mind, the World Climate Research Programme organised a workshop (held in June 2006) to document current understanding and to identify research and observations required to reduce current uncertainties associated with sea-level rise and variability. While sea levels have varied by over 120 m during glacial/interglacial cycles, there has been little net rise over the past several millennia until the 19th century and early 20th century, when geological and tide-gauge data indicate an increase in the rate of sea-level rise. Recent satellite-altimeter data and tide-gauge data have indicated that sea levels are now rising at over 3 mm year(-1). The major contributions to 20th and 21st century sea-level rise are thought to be a result of ocean thermal expansion and the melting of glaciers and ice caps. Ice sheets are thought to have been a minor contributor to 20th century sea-level rise, but are potentially the largest contributor in the longer term. Sea levels are currently rising at the upper limit of the projections of the Third Assessment Report of the Intergovernmental Panel on Climate Change (TAR IPCC), and there is increasing concern of potentially large ice-sheet contributions during the 21st century and beyond, particularly if greenhouse gas emissions continue unabated. A suite of ongoing satellite and in situ observational activities need to be sustained and new activities supported. To the extent that we are able to sustain these observations, research programmes utilising the resulting data should be able to significantly improve our understanding and narrow projections of future sea-level rise and variability.
  46. Wondering Aloud at 03:38 AM on 13 May 2009
    A broader view of sea level rise
    Good Post, I don't know how real the error bars can be on this, but I appreciate their existence in any event. I think we are seeing uncertainty being addressed and perhaps over simplified explanations are wrong no matter which side puts them forward. I wonder what a best straight line fit would tell you? Do you have a steady rise with rate variation due to climate variation or some other cause? Or is a curve as above really a better fit? Is it my imagination or do times of fast temp increase not match real great with times of maximum sea level rise? Is there a time lag? Much to think about.
  47. A broader view of sea level rise
    Steve, I am very familiar with the instrumental error found by Josh Willis. The significant ocean cooling previously reported was the result of an error in the fall rate of the instrument. Josh Willis is a fine scientist. Even after the error was corrected, the oceans have not warmed since 2003. That is a huge problem for anyone who understands the claim of a radiative imbalance for our climate system.
  48. A broader view of sea level rise
    Philippe, I cannot recall if Hansen says it exactly the way Roger Pielke, the ISI highly cited climatologist I referenced above, says it. If you understand the assertion made by Hansen, then the conclusion in unavoidable. Is there a radiative imbalance or not? Is there any physical theory that would allow for a radiative imbalance in one year and not in the following year? Yes, a volcanic eruption would tend to block the sun for a period of time. It happened with Pinatubo and the oceans cooled. Other than volcanoes, there is very little noise. Absent a volcanic eruption, the radiative imbalance would be there year after year after year. Where is all that heat going? A miniscule amount is stored in dirt and rocks, even less in the atmosphere, and the vast majority is stored in the oceans. There is no competing theory. Hansen's abstract at http://www.sciencemag.org/cgi/content/abstract/308/5727/1431 states the following: "Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 ± 0.15 watts per square meter more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years." The oceans definitely did warm in the 1990s. This paper was published in 2005. Hansen has not been touting ocean heat content since it has been determined the oceans have not warmed since 2003.
  49. A broader view of sea level rise
    Hi John: the link to Church 2006 didn't work for me. I wanted to see why in Figure 1 the standard deviation, after narrowing from 1870 to about 1995 then seems to broaden again. The other tidbit I found surprising was the apparently much greater effect of El Chichon vs Pinatubo. I think Ron Cram would like your old post: http://skepticalscience.com/Mystery-of-the-vanishing-ocean-heat.html and the linked update.
  50. Philippe Chantreau at 02:03 AM on 13 May 2009
    A broader view of sea level rise
    Ron says: "If AGW theory is true, ocean heat content and sea level would rise uninterrupted year over year over year." All noise would completely disappear? Why? References on that assertion (real papers, not blog posts)?

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