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Comments 122651 to 122700:

  1. Watts Up With That's ignorance regarding Antarctic sea ice
    Jeff Freymueller at 11:16 AM on 10 March, 2010 ...the glaciers are unpersuaded by this claim and continue to lose mass anyway. Cussed things, glaciers are. Entirely immune to appeals for sympathy and understanding.
  2. Watts Up With That's ignorance regarding Antarctic sea ice
    HumanityRules at 11:14 AM on 10 March, 2010 I worry more about folks being able to compartmentalize different things, a necessary part of understanding complex phenomena. Take a brief glance at a globe and notice that the Arctic is situated in a radically different environment than the Antarctic and is notably different in features. Air and water circulation around each pole is quite different, the average elevation of Antarctica is much higher than the Arctic, there is land at the South Pole, no land at the North Pole, one place is a continent in its own right, the other not; the two extremes have in common latitude from the equator and that's about all. Trying to generalize the behavior of Antarctica to the Arctic is an error.
  3. Jeff Freymueller at 11:22 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    #72 HumanityRules, the details are really out of my particular expertise but I have known for quite a while that sea ice scientists have predicted drastically different responses for the Arctic and Antarctic sea ice. So this is not some story being made up after the fact -- my understanding is that the difference in response was in fact predicted. I am aware of no fundamental difference in response by hemisphere for land ice, predicted or observed. Alaska and Patagonia are doing similar things. Greenland and the Antarctic Peninsula, similar. But its different for sea ice. Sometimes the answer is simple, and sometimes it is not.
  4. Jeff Freymueller at 11:16 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    #58 sciencefan: "I do not see how the Antarctic is melting when the temperature rarely gets of freezing, except on the Antarctic Peninsula and the shore. So how is Antarctic ice melting. (Hint, it has to move to where it is less cold than freezing)." You may already know the answer to this based on your hint, but it is important to note that it is not necessary to melt Antarctic ice in place. All you need to do is have the glacier that the ice is part of dump the ice into the ocean, where it will melt soon enough. The fact that it is usually too cold for ice to melt is often held up as "proof" that Antarctica can't be losing mass, but the glaciers are unpersuaded by this claim and continue to lose mass anyway.
  5. Watts Up With That's ignorance regarding Antarctic sea ice
    Berényi Péter at 09:06 AM on 10 March, 2010 Looks like there is presently loss, but it's fun to watch scientific progress go "boink"* Here's a earlier posting on this topic from Real Climate: The Greenland Ice which discusses Johanessen et al plus some other work at the time. The open question at the time had to do with measurements at the margins of the ice sheet, which Johanessen points out was then problematic. The RC writeup looks forward to seeing results from GRACE, still in process in 2006. As it turns out, GRACE helps to refine the budget, tipping the balance of mass trends from positive to negative. *http://farm1.static.flickr.com/176/467836393_6d3ca8bca0.jpg
  6. HumanityRules at 11:14 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    So take home message. Antarctic sea ice - climate is complicated so we can't use arctic sea increases to either prove or disprove global warming. Antarctic land ice - It's simple more energy melts ice proving global warming. Arctic sea ice - It's simple more energy melts ice proving global warming. Do you not worry about the inconsistency here?
    Response: You don't need to be so cynical, HR :-) We go where the empirical observations take us. In this case, the Southern Ocean is warming at the same time that sea ice is increasing. So obviously this is a complex and counter-intuitive situation (and from a scientific point of view, these are the questions that really fascinate scientists). The long term projections from Turner 2009 is that eventually the warming trend will overcome the increased sea ice production and Antarctic sea ice will eventually decline.
  7. Watts Up With That's ignorance regarding Antarctic sea ice
    Tadzio, you are presumably referring to John's actual article (rather than subsequent comments) and the bit about less dense water on the surface acting to prevent warmer deep water from welling up. Keep in mind that none of this water just 'stays put'. Currents will carry it out to mix with the rest of the oceans. Indeed, that relatively warm water is brought to the Antarctic deeps from other parts of the globe. Note that even the cold water at the surface is getting warmer (per the first chart in the article)... just not as fast as it would be if these other factors (i.e. ozone driven air circulation, decreased surface water density, et cetera) weren't in play. The oceans as a whole are warming. These other factors are just minor fluctuations around that underlying trend.
  8. Watts Up With That's ignorance regarding Antarctic sea ice
    tadzio at 10:39 AM on 10 March, 2010 Assuming you mean water beneath and proximate to the ice shelves, it's giving up heat to change the phase of water from ice to liquid. Energy is of course conserved in the process so unfortunately this is only a temporary effect. In the long term the Antarctic will not be a reliable means of moderating the temperature of the planet, it's already inadequate as we can see from ocean temperatures.
  9. Watts Up With That's ignorance regarding Antarctic sea ice
    tadzio writes: So if the warmer water is being kept at the bottom these layers must be getting warmer ? where is all that heat going and whats it doing ? Warmer water kept at the bottom of what? What layers? All which heat? Sorry, but it's not clear whom you are responding to or what the question is. Can you be a bit more specific?
  10. Watts Up With That's ignorance regarding Antarctic sea ice
    So if the warmer water is being kept at the bottom these layers must be getting warmer ? where is all that heat going and whats it doing ? Cheers dave
  11. Water vapor is the most powerful greenhouse gas
    Well, you outweigh me a bit; I'm 3,780,000 ladybugs as of this morning. It's been a long day here and I'm a bit addle-brained right now, but I think you're talking about two separate issues. One is the units involved in comparing radiative forcing to gross Australian livestock metabolism, and the other is how to account for changes in radiative forcing over time.* Is that right? If so, I think we've taken care of the first part (units should be consistent on both sides, either comparing watts to watts or watt-days per year to watt-days per year). Then the other question is about radiative forcing and how to handle changes therein over time. If CO2 and everything else were constant, RF would be constant too (and there'd be no need for this website!) Unfortunately CO2 is increasing, so the RF associated with CO2 is likewise increasing over time. Now, I may have screwed up the calculations somewhere, and I'm too tired to re-check this, but apparently when I wrote that original reply to Mizimi I'd calculated that annual increase in RF as 0.03 W/m2 over the whole earth. (I would not be the least bit surprised to learn that I'd made an error somewhere there, but let's assume it's correct). Now, the RF itself doesn't "accumulate" from year to year, though the energy resulting from it does (until the earth comes back into radiative balance with its exoatmospheric environment). But you can still look at the annual increase in RF caused by the annual increase in CO2, and compare the power of that RF increase with some other thing (like Australian sheep metabolism). Of course, I may be confused about what you're saying, or I might be screwing up the calculations. Or I might be suffering from a case of DK effect. But this is how it seems to me. * This is a sentence that has probably never before been composed in all of human history!
  12. Visual depictions of Sea Level Rise
    @Berényi Péter -- See the webpage http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/altimetry-data-and-images/index.html In the download options box, check the Time Series box and the Global Isostatic Adjustment option is enabled. That website probably has the answers to many of your other questions.
  13. Watts Up With That's ignorance regarding Antarctic sea ice
    Ned @65, you just beat me to it. Just a few more comments. Peter @64. From their abstract: "An increase of 6.4 +/- 0.2 centimeters per year (cm/year) is found in the vast interior areas above 1500 meters, in contrast to previous reports of high elevation balance. Below 1500 meters, the elevation-change rate is –2.0 +/-0.9 cm/year, in qualitative agreement with reported thinning in the ice-sheet margins." The increase (or stability) of snow and ice above the melt line is known: http://www.skepticalscience.com/An-overview-of-Greenland-ice-trends.html What is of concern is the loss of ice below the melt line. Also, the data in the paper you provided are for 1992-2003, whereas the data from GRACE are for the period 2002-2009. Anyhow, I am not sure what this has to do with Antarctic sea ice and the fallacious claims made at WUWT? Your comments regarding Greenland ice loss should probably be posted at the URL provided above.
  14. Pete Dunkelberg at 09:23 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    USGS says http://climateprogress.org/2010/02/23/usgs-reports-dramatic-retreat-of-ice-shelves-in-southern-antarctic-peninsula/ find a link to a large pdf there.
  15. Watts Up With That's ignorance regarding Antarctic sea ice
    Berényi Péter writes: "Is there a loss?" Yes. See, elsewhere on this site: Accelerating ice loss from Antarctica and Greenland and An overview of Greenland ice trends among other posts and articles. My suggestion would be that, before asking such a relatively basic question, to use the "Search" box on the top left of this page ...
  16. Visual depictions of Sea Level Rise
    @ Berényi Péter "When we are talking about "sea level rise" it is not meant to be relative to some external reference frame but to "average coastal elevation". How this latter quantity is measured?" If one is trying to figure out how much increase in volume in the sea has taken place, for example due to steric expansion and meltwater addition to the oceans, then one wants to reference to the bottom of the ocean. For this, one applies the Global Isostatic Adjustment of about 0.3mm/yr. If one is interested in relative sea level to coastlines, then one must adjust for the local elevation changes of the land. Or if one is just looking at global changes on the average, then one uses sea levels without the glacial rebound or global isostatic adjustment. Using this type of reference, the global mean sea level rate-of-rise is about 0.3mm/yr less.
  17. Berényi Péter at 09:06 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    #34 doug_bostrom at 04:52 AM on 10 March, 2010 "Easier units on Greenland loss" Is there a loss? Published Online October 20, 2005 Science DOI: 10.1126/science.1115356 Recent Ice-Sheet Growth in the Interior of Greenland Ola M. Johannessen, Kirill Khvorostovsky, Martin W. Miles & Leonid P. Bobylev
    Response: Ned answers this in the following comment but just to deliver the science on a silver platter, satellite gravity measurements do find that the Greenland interior is in approximate mass balance where mass loss is balanced by increased precipitation. But the edges of Greenland are losing mass. The overall result is that the Greenland ice sheet is losing ice mass (Wouters 2008). More here...


  18. Pete Dunkelberg at 09:02 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    Sciencefan, the ice shelves melt from below. The air temperature has nothing to do with it. The thinning, weakening ice shelves offer less resistance to the great ice sheets (which tend to spread out due to their own weight) and so ice flows faster into the ocean. See “Extensive dynamic thinning on the margins of the Greenland and Antarctic ice sheets”.Pritchard et al. 2009 in Nature/advance online publication 23 September 2009, and their Map of Antarctica: Red and yellow indicate thinning ice. Note that the "small" West Antarctic Ice Sheet (WAIS) is the major concern along with Greenland.
  19. Watts Up With That's ignorance regarding Antarctic sea ice
    Peter, I downloaded the data off their FTP server here: http://nsidc.org/data/seaice_index/archives/index.html Click on the "Get extent and concentration data" hyperlink.
  20. Jeff Freymueller at 08:54 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    #30 Berényi Péter. No, you don't have to measure the volume of the ice sheet to measure the change in volume of the ice sheet. You just have to measure the change in the gravity field. So your argument is wrong. It is not just supposition, it is hard data. There are accurate explanations of it on this site, too.
  21. Water vapor is the most powerful greenhouse gas
    Ned, Thanks for the quick reply. You certainly gave me a better understanding of what Mizimi did with the metabolic rate, and how it affects the resulting answer. However I am still a bit lost on the radiative forcing. I think I know where I am going wrong. Radiative forcing would need to be changed in the same way metabolic influence would need to be due to the fact both are expressed in watts? But isn’t the radiatve forcing just relative to a set period, not a predictable increase? In order to do RF-Years wouldn’t we have to apply the change from year to year, and not the actual RF number? Thanks! By the way, apparently I weigh approximately 3,995,933 ladybugs. (wiki says .021 grams per ladybug)
  22. Berényi Péter at 08:20 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    #33 Albatross at 04:41 AM on 10 March, 2010 "I have downloaded the sea ice area data from NSIDC for Antarctica" Could you publish the link?
  23. Philippe Chantreau at 08:18 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    Steven Goddard talks about debating science and describes John's blog as "this Wonderland, where down is up and up is down." I take offense from that. Since the post has been left by moderators, I believe it should be addressed. For a quick comparison, I want to remind readers that WUWT is a place where the existence of natural deposition of carbonic snow on Earth was discussed as a serious possibility, a post done by Stephen Goddard. http://wattsupwiththat.com/2009/06/09/co2-condensation-in-antarctica-at-113f/ This is somewhat on topic with our thread since it is about Antarctica. The ensuing comments contain variations and apparently a partial recant on the original intent and meaning (i.e. the idea that Antarctica acts as a carbon sink because of deposition). Fortunately, some posters pointed in the right direction, and despite the overall confusion on phase changes apparent in the comments, an update later appeared. Even a cursory read of Skeptical Science will reveal the higher scientific standards that would prevent such a post to happen here in the first place.
  24. Watts Up With That's ignorance regarding Antarctic sea ice
    If you like science take a look at this article, it is in terms a reasonably knowledgeable person can understand. http://www.geolsoc.org.uk/gsl/site/GSL/lang/en/page7209.html It is a geologist point of view about ice shelf break up. I do not see how the Antarctic is melting when the temperature rarely gets of freezing, except on the Antarctic Peninsula and the shore. So how is Antarctic ice melting. (Hint, it has to move to where it is less cold than freezing). I believe interest in polar caps is due to the hype about rising ocean levels if said ice cap do melt all at once(unlikely). At the current rate it would take hundreds of thousands of years to melt away, assuming no more snow accumulation. we can breathe easier knowing we are safe from catastrophic polar melting, no matter what Al Gore shows in his movie. As for whether ice extent is due to warming, we can see that wind and ocean currents are the biggest operator in whether sea ice extent grows or shrinks. In the Arctic, NASA says that ocean currents and wind pushed out sea ice to warmer waters during the '07 record. And in the comments we see that the circumpolar winds an currents play a big part in expanding the range of the sea ice. Lastly, sea ice extent in the Arctic and in the antarctic are both within 2 standard deviations of satellite records, so what the big deal is, I do not know.
  25. Watts Up With That's ignorance regarding Antarctic sea ice
    Hello. Just to let you know I'm a genius in my own mind, and in the minds of my grandchildren. Because of that sometimes I will speak to elementary school children about weather, sun, and planets. Now what I see is that there are several variables with whats happening. Even though the cyclonic flow may have a lot to do with whats being observed, I would like to look at the fresh water vs salt water aspect. Since fresh water freezes at a higher temp than salt water, in very elementary terms I would like to explain it like this: If I put an ice cube on a plate and put it in a freezer, turn the temp up so it partially melts the water spreads out. Then I turn the temp down and it freezes further out. I could continue doing this till the ice cube is gone. So my question is would I be wrong to use this in an elemntary way to show a possible cause for the increase in ice extent. Thanks
  26. Water vapor is the most powerful greenhouse gas
    Okay, first of all I think that evaluating the impact of CO2 by comparison to the metabolism of Australian livestock is not necessarily the optimal way to visualize it. Kind of like weighing yourself and then converting to units of ladybugs based on a sample weight of a ladybug in grams found somewhere on the internet. But, since you asked ... Tadh writes: Why then is it inappropriate for an individual to calculate the total increase in heat or energy over a period of time (a year) based on the length of time given in the definition of a watt? Actually, it's not at all inappropriate in the right circumstances. My monthly electricity bill reports usage in kilowatt-hours. That is appropriate for a quantity that fluctuates over time, like household electrical usage. In this case, it's not necessary, since for both the animal metabolism and climate radiative forcing data we have just an annual average. When Mizimi writes "... a daily heat emission of 315 x 10E9 watts ..." that's not "daily" ... it's 315 x 10E9 watts full stop. When she/he multiplies that by 365 to get "114 x 10E12 watts per annum" that's actually "114 x 10E12 watt-days per annum", though Mizimi doesn't seem to understand the meaning of these units. Now, doing that conversion merely complicates things unnecessarily, since "114 x 10E12 watt-days per annum" is exactly the same as "315 x 10E9 watts" (ignoring leap-years). However, the real problem is that Mizimi converted the metabolic data to "watt-days per annum" but didn't convert the radiative forcing to the same units. In other words, one side of the comparison got multiplied by 365 but the other side didn't. Hope this helps. Let me know if it's still confusing...
  27. Rob Honeycutt at 07:58 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    To Steven Goddard... What gets me about your articles, such as the one regarding sea ice extent, is the fact that you are purposefully selecting out small aspects of weather and climate (which I'm sure we both would agree are highly complex systems) that potentially show cooling and hold them up as examples to prove a point you want to make. But all the while you IGNORE the preponderance of evidence that show exactly the opposite! Literally, what you do is tantamount to trying to convince an expedition of climbers to Everest that it's "down hill all the way" by pointing out only the times when they're going downhill while ignoring all the climbing!
  28. Watts Up With That's ignorance regarding Antarctic sea ice
    Thanks Ned, I'm reading the preprint as the published paper is not accessible for me.
  29. Tenney Naumer at 07:12 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    re: #30 Sorry dude, but Greenland's ice sheet is melting so badly that anybody can see it happening even from the low resolution satellite photos available at MODIS rapidfire. Be sure to check it out this July and August. We are talking snowcone at the ballpark in July.
  30. Antarctica is gaining ice
    Geo Guy at 07:00 AM on 10 March, 2010 Your argument is incomplete. You need to account for the GRACE data shown above and in any case the single year you cite is inadequate as a suggestion that the Antarctic ice sheet is trending upward in mass. Also, would you mind providing a citation for your quote?
  31. We're heading into an ice age
    There are a number of issues that affect a possible ice age - the sun (and related wobble to the earth) being one. The others include the melting of the arctic ice cap. With the ice in place, the climate is arid; with the ice melted, there is a source for water vapor - necessary for precipitation to happen. During the last major ice age, a portion of the arctic ocean remained open, thereby providing for a source of water for the snowfalls that covered North America (Russia on the other hand escaped glaciation). The third issue to be considered is a change to ocean currents - specifically the interchange of waters from the North Atlantic and the Arctic waters. It was noted in a number of studies in the 1930's that the arctic ocean was showing signs of warming.
  32. Peter Hogarth at 07:02 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    The satellite record for Antarctic Sea Ice has been extended back to late 1972 (see below), there is also evidence from even earlier satellites back to 1966 but work is needed to process this data. There are some intermittent series of vessel observations prior to this (used in the HadISST record), plus evidence from extensive records of positions of whale kills which indicates that sea ice was somewhat higher than present times prior to 1960s. Work is ongoing to reconcile modern vessel based estimates and satellite observations in order to check older records. Antarctic Sea Ice data: The Nimbus 5 ESMR data covers the early period from December 1972 to March 1977, with the Nimbus 7 SMMR combined with the Defense Meteorological Satellite Program's (DMSP) Special Sensor Microwave Imagers (SSMI) on -F8, -F11, and -F13 satellites providing data from October 1978 to December 2002. The small gap is filled using NSIDC data. This latter satellite Data set (1978 onwards) is most often seen in “Antarctic” charts and is now in a version (V2) compatible and calibrated with the 2002 onwards AMSR-E on the AQUA satellite, basically so that the data sets can be "spliced". The early satellite record is interesting because it shows higher sea ice extents than today, but from what I've read it is probable that there was an anomalous peak in the Antarctic sea ice extent in the early 1970s due to local "decadal" Ocean cycles. I'll do my best to get references for these points lined up but am at Oceanology conference...
  33. Antarctica is gaining ice
    It is difficult to consider that the land ice mass is melting when indications are that snow is accumulating on the land at an unprecedented rate: Surface snowmelt in Antarctica in 2008, as derived from spaceborne passive microwave observations at 19.35 gigahertz, was 40% below the average of the period 1987–2007. The melting index (MI, a measure of where melting occurred and for how long) in 2008 was the second-smallest value in the 1987–2008 period, with 3,465,625 square kilometers times days (km2 × days) against the average value of 8,407,531 km2 × days (Figure 1a). Melt extent (ME, the extent of the area subject to melting) in 2008 set a new minimum with 297,500 square kilometers, against an average value of approximately 861,812 square kilometers.” This evidence suggests that Antarctica, where 90% of the land based ice in the world resides, is increasing in mass.
    Response: The bottom line is satellite gravity measurements of Antarctica find that the continent as a whole is losing mass. Not only that but losing mass at an acclerating rate. I will repeat the graph showing the total mass loss from Antarctica as the empirical data doesn't seem to have sunk in yet:



    You're also correct in pointing out that snow accumulating in the East Antarctic interior is increasing, presumably due to increased precipitation caused by more humid conditions caused by warming air. That Antarctica is losing mass at an accelerating rate while gaining mass in the interior is a testament to the sensitive nature of ice sheet dynamics - ice sheets are proving more sensitive than previously realised and are sliding into the oceans at a faster rate.

    This is also borne out by paleo studies that have looked at ice sheet and sea level behaviour in the past and found sea levels to be over 6 metres higher than current levels when temperatures were only 1 to 2 degrees warmer than now. Multiple lines of evidence point to the same answer - the ice sheets are sensitive to warming temperatures and are going to cause significant sea level rise over this century (and beyond).
  34. Watts Up With That's ignorance regarding Antarctic sea ice
    Steve Goddard at 06:05 AM on 10 March 2010 Assertion is not argument, Steven. I'm left to conclude you have no useful response to Tamino's disintegration and disposal of your hypothesis w/regard to snow cover and model predictions. How you care for your credibility is of course a personal choice for you to make. As to Watts' site, if you prefer a location that is more tolerant of misunderstanding that too is your choice, but I'm won't be joining you there. I've really come to appreciate the scrupulous moderation here as well as the site's firm attachment to science.
  35. Berényi Péter at 06:55 AM on 10 March 2010
    Does record snowfall disprove global warming?
    #73 Jeff Freymueller at 03:04 AM on 10 March, 2010 "melting is the dominant effect" Of course it is. But melting is only driven by air temperature if there is a hot turbulent wind. Even then 260 m3 of air should be cooled down by 1°C to melt 1 kg 0°C snow. Not very effective. Also, it depends on how thick the snow is. If wind cannot blow through, surface area for heat exchange is severely limited. Actually it is worse than that. If wind blows through loose snow, air gets saturated by water vapor. At 0°C saturation absolute humidity of air is 4.84 × 10-3 kg m-3. If air in wind would be at 80% relative humidity, it means that on top of melting 1 kg snow, about 0.25 kg meltwater should be evaporated as well. As evaporation requires 6.76 times more heat than melting (per unit mass), the actual drop in air temperature is 2.7 times greater (or more air is needed). Otherwise, heat conduction of air being rather low, just a thin layer above snow cools down to 0°C and that's it. Melt interrupted. If sky is cloudless and air is dry, snow being a pretty good black body in IR, radiative cooling to space kicks in. Black body radiation at 0°C is 315 W m-2. Even with the narrow atmospheric window it can get quite large if air is dry. On the other hand if there is some soot in snow, albedo decreases to 80% (2 ppm soot is more than enough) and sun is shining faintly, let's say it gets 100 W m-1 irradiation, the 20 W m-1 absorbed is enough to melt 1 kg m-1 in less than five hours (provided radiative cooling is not taken into account). If snow is darker or sun is brighter, melt is accelerated proportionally. As melt is started, snow albedo decreases even with no soot whatsoever. And most of soot is not washed away by meltwater immediately, it tends to get enriched in upper layer (at 220 ppm soot albedo drops to 25%, rather dark). But, beyond doubt, the most effective agent is lukewarm rain.
  36. Watts Up With That's ignorance regarding Antarctic sea ice
    Steven Goddard says: "Why are you ignoring this NASA map? http://earthobservatory.nasa.gov/images/imagerecords/6000/6502/antarctic_temps.AVH1982-2004.jpg" Your question is more appropriately directed to yourself. Take a look at the map. Notice the warming trend in the oceans around Antarctica, you know, where SEA ice is located.
  37. iPhone app version 1.1 - now with search, image viewer and Twitter!
    From the Discovery interview, I found this to be a gem of particular clarity: We can have the most confidence in scientific results when we have multiple lines of measurement showing the same thing. With global warming, there are multiple lines of evidence that all point to humans being the main contributor. For starters, we know exactly how much carbon dioxide is being added to the air. We can double-check that by measuring carbon isotopes in the atmosphere. We can triple-check that by measuring the amount of oxygen in the air to see if the amount of oxygen is falling in line with the fossil fuel burning. So we know we’re causing the rise in CO2. Now the next step is: What are the effects of all the CO2 in the air? And we can measure that by satellites that measure how much radiation is escaping from Earth out into space. And what they are observing is that there is less radiation escaping at the very wavelengths that greenhouse gases absorb energy. So that’s the human fingerprint, that CO2 is trapping heat. Another confirmation of this is that surface measurements also measure the amount of radiation that is coming back down from the atmosphere, and they find the same thing: That there is more radiation coming back down at the very wavelengths that greenhouse gases trap heat. So there are multiple lines of evidence that CO2 is trapping heat. In this interview John refers to the trap of minutiae, how easy it is to get lost scrutinizing iota. Plot and scenery in this drama are dominated by bulky, confirmed physical effects, poor fodder for argument, so folks who reject basic physics are left to make the little objections they have seem as big as possible. The range of those small objections is itself narrow, so we hear variants of various quibbles endlessly repeated. At the end of the day if nothing else it's boring to hear this stuff spinning endlessly like a prayer wheel on a windy day.
    Response: You know, I read that excerpt from the Discovery interview and think "man, I say the word 'and' a lot!" But then I've always been a glass-half-empty kind of person :-)
  38. Water vapor is the most powerful greenhouse gas
    Ned, i am interested in your refute of Mizimi's calcualations in post #86. I was wondering if you could answer a question for me. I am no where near the level of discussion on this board. Your first point has to do with the definition of a watt. A watt is equal to one joul/s. The definition of a watt includes a specific amount of energy over a specific period of time. j/s. Why then is it inappropriate for an individual to calculate the total increase in heat or energy over a period of time (a year) based on the length of time given in the definition of a watt? Second, my understanding of radiative forcing is limited. I beleive it is defined as the change in irradiance at the tropopause. It is determined relitave to a base period (usually 1750). The IPCC defines radiative forcing as follows: "Radiative forcing is a measure of the influence a factor has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system and is an index of the importance of the factor as a potential climate change mechanism. In this report radiative forcing values are for changes relative to preindustrial conditions defined at 1750 and are expressed in watts per square metre (W/m2).":36 Neither my previous definition nor the IPCC definition refer to change per unit of time. As such how and why would Mizimi have to calculate radiative forcing-years? sure one year may have an increase in radiative forcing, and another a decrease, but they are all relative to 1750 and are not necessarly cumulative. To better explain myself and my understanding of radiative forcing i will use simplified means. Say year XXX1 has a radiative forcing value of +1. this would mean that it is +1(w/m2) over 1750. Assume year XXX2 has a reading of +1 as well, year XXX 3 has a reading of +2, the cumulative radiative forcing is + 2 not +4, right? Love this series of posts, sorry if i am dumbing it down too much.
  39. Watts Up With That's ignorance regarding Antarctic sea ice
    Steve Goddard writes: You must have missed the fact that winters during the past decade were the snowiest on record in the Northern Hemisphere. Actually, that and much more are discussed in great detail in John's post that Doug linked to, elsewhere on this site: Does record snowfall disprove global warming? I'd second Doug's remark encouraging you to check out that page, and comment if you see fit. Goddard continues: If you want to discuss science, come do it over on WUWT. No, thanks. Many of us have had more than ample negative experiences with WUWT. I'm honestly not trying to be insulting or dismissive, but there's very little actual science there. As far as I can tell it's primarily about entertainment. If you stick around here, you'll quickly find more substantive discussion and better food for thought. Ultimately, real science is more interesting than fake science. Cheers, Ned
  40. Watts Up With That's ignorance regarding Antarctic sea ice
    Steve Goddard @47: I'd appreciate an answer to my question @44: "I am curious then why you chose to post the incorrect image here at #32, and not the same (and correct) image you used in your report at WUWT?" Do you also now agree, after reading the links to Turner et al. (2009) and Ned's comments, that Turner et al. (2009) did not claim that Antarctica is cooling? In the spirit of honesty and correctness, I would suggest that you correct your blog at WUWT to reflect the science (from the scientific literature) and other facts presented to you here concerning the southern oceans and Antarctic sea ice. We all make mistakes, one true test of scientific integrity is admitting to having made them and then promptly correcting them. PS: I'm sorry but, with respect, WUWT is not a science blog.
  41. Watts Up With That's ignorance regarding Antarctic sea ice
    Sordnay writes: omeone could help me locating that Section 2c? thanks That's referring to section 2(c) of the preprint of Mears & Wentz manuscript about the TLT channel posted in the same folder on the RSS website. See pages 9-10 of that pdf ("Construction of the RSS V3.2 lower tropospheric temperature dataset from the MSU and AMSU microwave sounders"). The manuscript was published as Mears & Wentz 2009 in the AMS's Journal of Atmospheric and Oceanic Technology. You might want to refer to the published version rather than the preprint (I'm not sure whether there were any changes).
  42. Steve Goddard at 06:05 AM on 10 March 2010
    Watts Up With That's ignorance regarding Antarctic sea ice
    Hey Doug, You must have missed the fact that winters during the past decade were the snowiest on record in the Northern Hemisphere. http://wattsupwiththat.com/2010/03/02/2001-2010-was-the-snowiest-decade-on-record/ Tamino hinted that winter snowfall might be declining, but he just couldn't prove it yet. (Declining to a record maximum is an interesting concept.) If you want to discuss science, come do it over on WUWT. I've spent enough time in this Wonderland already, where down is up and up is down.
  43. Watts Up With That's ignorance regarding Antarctic sea ice
    About RSS TLT Channel, there is something that bothers me, it's the only channel that is not registered to Latitude -80º it only reaches to -70º so almost the whole Antarctica is not measured. It's also noticeable the difference between version 3.2 and 3.1 the difference is greater than the anomaly registered at Antarctica or better, near Antarctica. see last figure at http://www.remss.com/data/msu/support/Changes%20from%20TLT%20Version%203.1%20to%203.2.pdf "We reduced the systematic bias that occurs due to spatial-derivative effects in the TLT extrapolation process that can be large at high latitudes. The effects of this bias are particularly large near Antarctica. (see Section 2c in the preprint for a discussion)" Someone could help me locating that Section 2c? thanks
  44. Watts Up With That's ignorance regarding Antarctic sea ice
    There is only one very brief note in Turner 2009 about temperature trends. Under Results, they say: "[14] The increase in southerly flow will give lower air temperatures, and will help maintain the polynyas along the coast. Combined, these will lead to greater ice production [Comiso, 2000] and also promote enhanced ice advection northwards." That's all. In the context, it's not even clear whether this is suggesting that the increased southerly flow associated with the stratospheric ozone hole will make air temperatures over the Southern Ocean cooler than they were previously (i.e., an actual cooling trend) or just cooler than they would be without the ozone hole (i.e., not necessarily actual cooling over time). Regardless, however, this is irrelevant. The proper place to determine whether the Southern Ocean is currently warming or cooling is to look at actual measurements, not at the results of climate model experiments like Turner 2009. Actual data show the ocean is in fact warming. What's interesting about Turner 2009 (and it is interesting ... I'd encourage you to read the whole paper) is that it discusses the mechanisms of how and why sea ice in the Southern Ocean behaves as it does. If you're only interested in the bottom line ("Will sea ice extent increase or decrease over the course of this century?") here's what Turner 2009 concludes: "Projections of the climate for the rest of this century using the AR4 models suggest a large decrease (approximately 30%) in Antarctic sea ice by 2100 [Arzel et al., 2006; Bracegirdle et al., 2008] as stratospheric ozone levels recover but greenhouse gas concentrations rise. We can therefore expect to see a gradual slow down in the rate of increase of SIE before the reduction takes place later in the century. Many of the models used within the AR4 exercise incorporate an estimated recovery of stratospheric ozone amounts during the spring, with the ozone hole recovering by the second half of the century. This would tend to reduce the wind speeds around the continent and presumably result in a reversal of the trends in SIE that we have examined here."
  45. Watts Up With That's ignorance regarding Antarctic sea ice
    Goddard,re #29. I am commenting on what John posted in his article, and limiting my discussion to the science being discussed here on this thread. That said. I am curious then why you chose to post the incorrect image here at #32, and not the same (and correct) image you used in your report at WUWT. I am "ignoring" that map because it has been superseded by a superior product. The science has advanced. And, if you stick around long enough, I think that you will find this site intellectually stimulating rather than "sloppy".
  46. Watts Up With That's ignorance regarding Antarctic sea ice
    It does seem a bit strange to refer people to either the older version or the newer version of that graphic as evidence of cooling in the Southern Ocean. Both versions actually show the ocean warming; the only large differences involve the temperature trend over land (formerly cooling, now warming).
  47. Watts Up With That's ignorance regarding Antarctic sea ice
    @7: "Antarctic sea ice extent is increasing (for whatever reason) and the trend is significant." @32 (Quoting NSDIC) "Through the austral summer, the total extent of sea ice surrounding the Antarctic continent has remained within two standard deviations of the 1979 to 2000 average." These statements are contradictory. If the extent of the ice has remained within 2 standard deviations of the mean, then it cannot be significant at the 5% level. Phil Jones could explain it to you, don't ask teh Daily Mail.
  48. Watts Up With That's ignorance regarding Antarctic sea ice
    Ned at 04:55 AM on 10 March, 2010 Ned's advice is good. Especially, never forget that you're writing for a silent audience most of whom have no notion of past issues or why patience may be wearing thin. Despite the fact that Steven has been wrong so often in the past and has left so many challenges to his accuracy unanswered, it is best to treat each new mistake individually.
  49. Watts Up With That's ignorance regarding Antarctic sea ice
    Steve Goddard, the image that you refer people to from EarthObservatory is incorrect. The actual source of the image that you provided is: http://earthobservatory.nasa.gov/IOTD/view.php?id=6502 Below that image they state that: "(Editor’s note: This image was first published on April 27, 2006, and it was based on data from 1981-2004. A more recent version was published on November 21, 2007. The new version extended the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series.)" They even provide a link to the correct image at: http://earthobservatory.nasa.gov/IOTD/view.php?id=8239 Of note is the marked warming evident over the polar oceans. I have provided a caveat about the temperature trends over the continent itself. Also, please read the actual report by Turner et al. (2009), nowhere do they state that Antarctica has cooled. They state: "a. The loss of stratospheric ozone has intensified the polar vortex, a ring of winds around the South Pole, altered weather patterns around the continent, and increased westerly winds by about 15% over the Southern Ocean in summer and autumn. b. This has resulted in the Antarctic becoming more isolated and there being little change in surface temperature across the bulk of the continent over the last 30 years." And, "a. The waters of the Antarctic Circumpolar Current (the largest ocean current on Earth) have warmed more rapidly than the global ocean as a whole." And, "a. While sea ice extent across the Arctic Ocean has decreased markedly over recent decades, around the Antarctic it has increased by 10% since 1980, particularly in the Ross Sea region. b. This increase is a result of the stronger winds around the continent, changes in atmospheric circulation and the isolating effect of the ozone hole. c. In contrast, there has been a large regional decrease of sea ice to the west of the Antarctic Peninsula, because of changes in the local atmospheric circulation." Report summary at: http://www.scar.org/publications/occasionals/ACCE_top_10_points.pdf I encourage readers here to read the report.
  50. Watts Up With That's ignorance regarding Antarctic sea ice
    Steve Goddard writes: They are very intelligent and thoughtful people, and don't partake in the same intellectual sloppiness as people over here I understand why you might feel less than thrilled about this thread, but I hope you'll stick around and explore more of the site. John Cook and others have put a lot of effort into creating what's clearly one of the best climate science blogs anywhere. The emphasis on exploring the peer-reviewed literature, and clearly and concisely summarizing the best current understanding of elements of the global climate system, is pretty much unmatched.

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