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Bob Lacatena at 04:24 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
This is clearly wrong, because another, often ignored theory is right. Given the upcoming holiday season, I think it's time that everyone face the fact that global warming is caused by Eurasian Leprechaun Farts (ELFs). The evidence is indisputable. The greatest warming is at the north pole (home to the jolly old ELF himself, and his vast army of worker ELFs). It began coincident with two known changes in ELF behavior, a dramatic increase in population, and a switch in diet to coprolite consumption (which itself may have caused the population explosion -- a very deadly positive feedback). Different camps argue fiercely over which of these is the true, underlying cause, but the fact of the matter is that ELFs are deadly. The scientific impacts of ELFs on the earth's atmosphere as SBD gases (silent but deadly) was proven hundreds of years ago by Arse-nius, and is not really subject to rational dispute. Those who emphatically profess otherwise are merely, so to speak, cutting the cheese. Of course, the nefarious fossil food industry is expending vast sums of money to keep this hushed up. And when they can't keep it up, they try to confuse the common man by recasting the debate in emotional terms as a War on Christmas! Whether it is the increase in Eurasian leprechaun population or the newly found leprechaun delight for their products, the fact remains that any proper solution -- a reduction in coprolite sales and consumption -- will hurt their recent huge upswing in profits from coprolite mining and distribution. Their entire financial empire will crumble if the problem is addressed, as it must be if we are to save civilization as we know it. People need to wake up to this! Admit that ELFs are the problem and curtail the fossil food industry now, before it's too late! -
The human fingerprint in the seasons
HR, Your question is, if GHG feedbacks are a portion of any solar warming, how do we determine whether the fingerprint in question is a fingerprint of CO2 warming and not of the feedback portion of a hypothetical solar warming. Did I understand that correctly? The answer is that this is what the simulations predict. With solar warming, summers should get warmer faster than winters, and vice versa with CO2 driven warming, all feedbacks included. The same goes for all the other fingerprints mentioned. The precise nature of the fingerprint is derived from the models, and observations have been consistent with those predictions. Does that answer your question? If you dislike invoking models, here are a couple things to consider that illustrate why your "40-60% GHG component" calculation is too simplistic for predicting the nature of the fingerprints: Water vapor has a very short residence time in the atmosphere (about 9 days). This means that any feedback generated during the summer is not going to have a long term impact into the winter. Instead, the feedback will follow proportionally along with the initial warming. Since the solar impact during the winter is greatly reduced, the GHG feedback that goes along with it will also be reduced. The opposite would be true for CO2. For the day/night signature, remember that the entirety of the solar influence is exerted during the day, while the GHG feedback effect is spread out somewhat over the full 24 hour cycle. It would take a very strong discrepancy in GHG effect from night to day in order to cancel out the solar fingerprint. -
Ed Davies at 03:55 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
But if feels to me like the years are getting shorter. ;-) -
shdwsnlite at 03:02 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
This argument seems to be similar to another I ran across, that it was space debris causing the warming. Though i don't remember the exact reason they said it was causing the warming. Friction as it entered the atmosphere? Adding mass to the Earth causing the days or orbit to change? Whichever it was there was nothing that could shake them from that belief. -
muoncounter at 03:00 AM on 18 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#17: "... but there are big questions" I'm not sure of the overall value of this small forest of linked papers towards the topic of this thread. At least Murray et al 2010 confirm a period of accelerated ice loss, as shown in this thread's Figure 1: Synchronous acceleration and thinning of southeast (SE) Greenland glaciers during the early 2000s was the main contributor that resulted in the doubling of annual discharge from the ice sheet. We show that this acceleration was followed by a synchronized and widespread slowdown of the same glaciers, in many cases associated with a decrease in thinning rates ... Since the overall trend (again referring to Figure 1 above) is sharply down, can we not interpret the 'widespread slowdown' and 'decrease in thinning rates' as minor contributors to the trend? Some of the other papers linked in #17 refer to accumulation, which is not at all the question discussed here. -
MarkR at 02:51 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
#17: Mike, there is some friction in outer space. You can disperse energy by collisions with objects, by tidal heating or, most consistently we are slowed slightly by the light pressure from the Sun. Because we're going around the Sun, sunlight actually strikes us at a slight angle to our trajectory at any point in time. In effect, there is a tiny component of the light motion that is opposite to our direction. This transfers momentum to the Earth, slowing us down. There is also the small light force from the Sun pushing us directly outwards, but that is technically not friction since it doesn't depend on our velocity, but on our position... -
TheCaz at 02:25 AM on 18 December 2010It's the sun
Sorry, but it does not. The question was whether solar activity and surface temperatures were always coupled in the holocene, or whether there were other periods of uncoupling. Your graphs do not contain any data of solar energy output at all. So the question was not addressed in your response. I understand you have preented data comparing CO2 to surface temps, but that is not what I asked. -
Ebel at 02:08 AM on 18 December 2010Stratospheric Cooling and Tropospheric Warming
It is less important to explain "how it is", but the more important, "why it is so". And to just heard the important role of the vertical circulation and where be the begin of vertical circulation. (see #233 and #234). -
Arkadiusz Semczyszak at 01:42 AM on 18 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
”The mass loss of Greenland’s outlet glaciers is not only expected to continue but to increase their acceleration as well.” ... but there are big questions, how? Greenland Ice Sheet model parameters constrained using simulations of the Eemian, Robinson, Calov, and Ganopolski, 2010.: “The most“realistic” simulations of the modern GIS (less volume and surface area) were obtained in the experiments that produced completely unrealistic simulations of the Eemian GIS (ALMOST COMPLETE MELTING [!?]).” “Finally, in spite of limitations of the model used and remaining uncertainties, our work indicates that using past and present constraints together, it is possible to rule out both too sensitive and too insensitive model versions, which enhances the credibility of modeling the stability of the GIS under global warming scenarios.” “... enhances the credibility of modeling the stability ...” - Is that enough? I recently watched the entire "scientific achievements" Edward Hanna (and citation of his papers) - an outstanding scientist, whom I really appreciate. Here are some interesting results: Observed and Modeled Greenland Ice Sheet Snow Accumulation, 1958–2003, and Links with Regional Climate Forcing, Hanna et al., 2006.: “Unusually high accumulation in southeast Greenland in 2002/03 leads the authors to study meteorological synoptic forcing patterns and comment on the prospect of enhanced climate variability leading to more such events as a result of global warming.” A spatially calibrated model of annual accumulation rate on the Greenland Ice Sheet (1958–2007), Burgess et al., 2010.: “The only statistically significant temporal change in total ice sheet accumulation in the 1958–2007 period occurred between 1960 and 1972, when a simultaneous accumulation increase and decrease occurred in west and east Greenland, respectively. No statistically significant uniform change in ice sheet-wide accumulation is evident after 1972. However, regional changes do occur, including an accumulation increase on the west coast post-1992. The high accumulation rates of 2002–2003 appear to be confined to the southeast.” Ocean regulation hypothesis for glacier dynamics in southeast Greenland and implications for ice sheet mass changes, Murray et al., 2010.: “We argue that this warming and subsequent cooling of the coastal waters was the cause of the glaciers' dynamic changes. We further suggest that the restrengthening of the EGCC resulted in part from cold water input by increased glacier calving during the speedup and increased ice sheet runoff. We hypothesize that the main mechanism for ice sheet mass loss in SE Greenland is highly sensitive to ocean conditions and is likely subject to negative feedback mechanisms.” Annual accumulation for Greenland updated using ice core data developed during 2000–2006 and analysis of daily coastal meteorological data, Bales et al., 2009.: “The much lower accumulation in the southwest and the much higher accumulation in the southeast indicated by the current map mean that long-term mass balance in both catchments is closer to steady state than previously estimated. However, uncertainty in these areas remains high owing ... [?!]” Hydrologic response of the Greenland ice sheet: the role of oceanographic warming, Hanna et al. 2009.: “Additional evidence from meteorological reanalysis suggests that high Greenland melt anomalies of summer 2007 are likely to have been primarily forced by anomalous advection of warm air masses over the ice sheet and to have therefore had a more remote atmospheric origin.” Oceanic control of the warming processes in the arctic – a different point of view for the reasons of changes in the arctic climate, Marsz, Styszyńska, 2009.: “Reaction of sea ice is the main mechanism controlling the heat content in water carried to the Arctic and influencing the SAT. Sea ice may either increase or limit the heat flow from the ocean to the atmosphere. The genesis of the ‘Great warming of the Arctic’ in the 1930s and ‘40s is the same as that of the present day.” “Dickson et al. (1996) showed that the formation of subtropical water in the Sargasso Sea on a multidecadal scale is functionally connected with convection processes in the Greenland and Labrador seas, albeit shifted in phase in relation to each other. These are elements of a general thermohaline circulation and they are dynamic elements of unquestionably natural character.” ”This means that observed in 1880-2007 climatic changes in the Arctic were promoted by the transport of variable heat content from the tropics with the oceanic circulation; they also have a natural and non-anthropo-genic genesis.” Increased Runoff from Melt from the Greenland Ice Sheet: A Response to Global Warming, Hanna et al., 2008.: “Significantly rising runoff since 1958 was largely compensated by increased precipitation and snow accumulation. Also, as observed since 1987 in a single composite record at Summit, summer temperatures near the top of the ice sheet have declined slightly but not significantly, suggesting the overall ice sheet is experiencing a dichotomous response to the recent general warming: possible reasons include the ice sheet’s high thermal inertia, higher atmospheric cooling, or changes in regional wind, cloud, and/or radiation patterns.” Greenland’s contribution to global sea-level rise by the end of the 21st century, Graversen et al., 2010.: “Greenland contributes 0–17 cm to global sea-level rise by the end of the 21st century. This range includes the uncertainties in climate-model projections, the uncertainty associated with scenarios of greenhouse-gas emissions, as well as the uncertainties in future outlet-glacier discharge.” I especially recommend in this paper: Fig. 6 (a) Partitioning Recent Greenland Mass Loss, van den Broeke et al., 2009.: “Without the moderating effects of increased snowfall and refreezing, post-1996 Greenland ice sheet mass losses would have been 100% higher. [...]”Moderator Response: [Daniel Bailey] Arkadiusz, please furnish a concluding summation to give the readers an idea of why you post the linked references with their quoted texts. Trying to guess at that hidden meaning from your post is difficult. Thank you! -
Arkadiusz Semczyszak at 01:41 AM on 18 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
@Karamanski “Is it likely that warming in Greenland and the rest of the Arctic be the cause of the recent trend towards colder and snowier winters in the Midwest?” Overland, 2010. : says that yes, that is: “While individual weather extreme events cannot be directly linked to larger scale climate changes, recent data analysis and modeling suggest a link between loss of sea ice and a shift to an increased impact from the Arctic on mid-latitude climate (Francis et al. 2009; Honda et al. 2009). Models suggest that loss of sea ice in fall favors higher geopotential heights over the Arctic. With future loss of sea ice, such conditions as winter 2009-2010 could happen more often. Thus we have a potential climate change paradox. Rather than a general warming everywhere, the loss of sea ice and a warmer Arctic can increase the impact of the Arctic on lower latitudes, bringing colder weather to southern locations.” Others have “slightly” different opinion: Are cold winters in Europe associated with low solar activity?, Lockwood et al., 2010.: “We show that cold winter excursions from the hemispheric trend occur more commonly in the UK during low solar activity, consistent with the solar influence on the occurrence of persistent blocking events in the eastern Atlantic. We stress that this is a regional and seasonal effect relating to European winters and not a global effect.” Low solar activity is blamed for winter chill over Europe, Benestad, 2010.: “The results of Lockwood et al (2010) fit in with earlier work (Barriopedro et al 2008) and provide further evidence to support the current thinking on solar-terrestrial links.” Tree rings and past climate in the Arctic, Juday 2010.: “Because many of the climate records available in this part of the world begin only in the late 1940s or early 1950s (during the one of the coldest periods of the 20th century) and continue to the present (the warmest period of the last millennium), the instrument-based record indicates a higher rate of temperature increase than the longer-term reconstructions that incorporate several cycles of temperature increases and decreases. This suggests that the strong late 20th-century warming (during the warm season) in western North America may have a considerable component of natural climate variability in the signal.” -
jorgepeine at 01:27 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
John and all others, a lot of patience sounds in your words ... I would have lost my temper ... congratulations to you! excellent job -
Yvan Dutil at 00:55 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
This one is easy to debunk. Earth position relative to the Sun is known within a few meter. There some discussion that there is a drift but I would be the order of a few meters per year at most. Astronomers are paranoiac about the Earth motion in space. Actually, there an international services only working on this issue. http://hpiers.obspm.fr/eop-pc/index.php?index=mission&lang=en&change_lang=true You will see on this web page that the Chilean Earthquake did not change the duration of the day by the way. -
ravcasleygera at 00:49 AM on 18 December 2010It's too hard
I would be interested to see some update of this rebuttal to take into account the growing belief that we need to get down to 350ppm CO2 (or even 350ppm CO2e) to prevent dangerous climate change. thanks.Response: [JC] This issue is addressed in Why it's urgent we act now on climate change. -
TOP at 00:35 AM on 18 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
Arctic as a heat sink I suppose we should be looking at the heat (energy balance) of the Arctic during high pressure events in the winter to see if it is higher or lower than in the past. It's not the temperature, but the energy balance that is important. Arctic highs allow warmer air to displace the colder air southwards. But that warmer air has to lose energy as there is no solar input in winter. I wish they wouldn't give accelerations in percentages. That is almost meaningless to me. I think what is meant is a change in velocity which is what should be said. Change in velocity without a time frame is meaningless and I only noticed that information provided in one instance. Figure 1 is meaningless without a corresponding figure showing the total amount of ice on Greenland. Figure 1 is over a very short timespan almost meaningless from a climatic standpoint. A perspective of several hundred years would be helpful.Moderator Response: [Daniel Bailey] Climate researchers are concerned with the change in the climate, including the change in the temperatures, hence the use of anomalies in the measurement of temperature change. In like fashion, ice researchers often measure change in ice sheet flows in percentages. Much the same thing. If you are unhappy with the wording of the post article, Mauri and I linked each reference for your easy perusal. Therein you may find the answers you seek. Lastly, Figure 1 contains incredible meaning and significance. As the very first linked reference shows, summer melt in Greenland saw a net 500 Gigatons of melt, or a bit more than the volume of Lake Erie of the US and Canada. That is a non-inconsequential amount to melt in just a few months. As such, the increasing melt signified by the curve on Figure 1 should give pause to sober minds everywhere. I invite you to visit Greenland in your several hundred years to convince yourself. -
Ken Lambert at 00:21 AM on 18 December 2010A new resource - high rez climate graphics
Rob Painting #19 Maybe the author should compare notes with Josh Willis whose latest information was that there was not much warming in the deep oceans (less than 0.1W/sq.m). If there is a large amount of 'up and down welling' then you would expect that CO2 as well as heat would be transported and well mixed in a vast volume of water. Such vast mixing of CO2 would result in an infinitesimal change in pH (acidification). There are plenty of claims of significant acidification of the upper layers of the oceans which does not fit with large flows of water to the deep.Moderator Response: Again, this is not the thread for discussion of ocean heat content. Any further off-topic comments may be deleted without warning. -
muoncounter at 00:17 AM on 18 December 2010Debunking this skeptic myth is left as an exercise to the reader
This is debunked very simply: there's no consensus. As shown by Iorio 2009, "the Earth's perihelion position is displaced outward by 1.3 cm along the fixed line of apsides after each revolution." We must therefore wait a million years or so to see which interpretation is correct. In the meantime, this page is of particular relevance here: The earth is shifting on its axis (40 miles per year). Twelve o’clock noon use to be the hottest part of the day. Now three o’clock in the after noon is the hottest part of the day. This is due to the earth shifting on its axis. The earth is also wobbling on it axis. This was discovered before the Chilean earthquake in 2010. I discovered it on the internet in 2008. At this rate, the hottest part of the day will soon be midnight. Pigs will fly. The oceans will turn to lemonade. Because everyone knows that anything discovered on the internet must be true. -
Eric (skeptic) at 23:50 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
I should end my off-topic excursion by saying I don't see a connection between the Greenland ice loss depicted above and AO (or NAO) even though the negative AO appears to sometimes pump warm air into Greenland in winter. -
Alexandre at 23:48 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
My reasoning would be similar to MarkR above: the closer sun would mean more W/m2 of energy getting here, and we do not observe that. OTOH, if we were getting closer, but that did not change the irradiance we get, then it's irrelevant to the point. -
Alec Cowan at 23:46 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
I agree with #9. Earth orbit apsis must be decaying some 0.2% per century -some 10 km a day- to get a warming effect the same order as observed. This reasoning cancels positive feedbacks with system inertia because "I feel" they are similar. Isn't i-feel-ogy epistemologically correct from a hedonistic point of view? -
HumanityRules at 23:35 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
So we all promise to avoid circular arguments? There is a favorite refrain on this website which goes it's the multiple lines of evidence that support AGW. I except the basic premise of the point but every time it's used as an argument to defend a criticism of any one particular line of evidence it seems to lose it's power. The use of circular arguements on the "The human fingerprint in the seasons" comments started to really bug me. -
Eric (skeptic) at 23:29 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#9 Karamanski, there may be a better explanation for cold midwest winters, http://nsidc.org/arcticmet/patterns/arctic_oscillation.html What is not shown in their diagram is the warmth flowing up into Greenland and (at the moment) eastern Canada. Here's a long term chart of the AO http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/month_ao_index.shtml and I would think that should match to cold outbreaks and lake effect snow, but the match is sporadic at best (e.g. 1977 and 2001, but not 2004) -
BaerbelW at 23:27 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
Apart from what others have already mentioned, I would have asked him what kind of globe he is looking at where Houston is "near the equator". But, then, it might just depend on his definition for "near"! Oh, and also, how relevant one specific location is when we talk about something global. -
Chemware at 21:46 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
One more reason - if the earth's orbit were decaying (shades of Star Trek !!) at a rate sufficient to cause the observed warming, then AGW is the least of our troubles ! -
MarkR at 20:44 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
We have satellites around Earth. If they measure more heat from the Sun, then more heat is arriving. This could be the Sun heating up, or us getting closer, or a combination. 'It's the Sun' explains why... it's not the Sun.Response: This is the answer I went with in my email reply. But interesting to read the other responses - circular reasoning, length of year, the lack of solar fingerprints, surface measurements of solar radiation - this hypothesis is falsified on many levels. I should throw out a few more skeptic myths, see what readers come up with as an interesting exercise (might save me some work too :-) -
RSVP at 20:36 PM on 17 December 2010Ocean acidification isn't serious
muoncounter #49 As per maps, it looks like the planet (and we humans) are in big trouble. The map (the red zone in particular) is an eye opener for me, as CO2 can only be accumulating overall (in both air and water), and will only increase in the atmosphere if the oceans warm. Its the red splotches that are of concern, which seem to indicate that CO2 will outgas even though CO2 in the atmposphere is already above its premodern "natural" equilibrium. And if this is the case, the CO2 ppm level should continue to rise or at least hold steady even if we were to stop burning fossil fuels today. This effect would be the ocean's "fault" for a while, (but of course we "intellegent beings" were the ones who put it there). Furthermore, if CO2 actually does cause warming, this should act as positive retro-feedback for both further warming and CO2 increase. I assume the only way for the CO2 level to go back down then is in getting minerally sequestered in a more permanent fashion as opposed to simply dissolving (temporarily) in water. Its as if the ocean's are actually masking the problem, one that is independent from above the acidification bio detriment. While warming is an evironmental problem, this one seems much bigger and easier to characterize. Maybe I am all wet as you say, but this is how it seems. -
Dan Olner at 20:12 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
I'd go with Bern's point about circular reasoning as the main problem. He's not understood the most basic point about spurious correlations. -
Rob Painting at 19:56 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
I kind of think we’d have noticed the year getting shorter. Bah, Doug beat me to it. -
Liam23 at 19:37 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
I would ask: if the earth's orbit is decaying, then why is the upper atmosphere not warming at the same rate as the lower? Why are nights warming more than days? Why are winters warming more than summers? With thanks to the new Skeptical science guide for clarifying these points for me! -
Riduna at 19:18 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
If earths orbit were decaying to the extent that it alone was responsible for global warming, then one would expect an increase in solar radiation at the earths surface which has been observed (Pinker 2005) but one would also expect that radiation to show consistent increase over the last 50 years. Measurements show that solar radiation reaching the earths surface showed a decline until 1993 and some increase in the following decade. During the period of decline in solar radiation, global temperatures rose. Decay of the earths orbit could not have produced global warming which occurred from 1963-1993 Further, the increased solar radiation reaching the earths surface since 1993 has been less than that required to account for the rise in global temperatures. This shows that change in the earths position relative to the sun have been too small to account for temperature increases. Ergo, rising greenhouse gas concentration accompanied by an almost linear rise in temperature remain the most logical explanation. -
Doug Mackie at 19:05 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
Kepler’s 2nd law of planetary motion: orbital period squared is proportional to semimajor axis cubed. Roughly that means that the length of a “year” is proportional to the distance from the Sun. Where a “year” is here defined relative to the background of fixed stars (sideral). I kind of think we’d have noticed the year getting shorter. Mercury 58 million km from Sun (OK so it varies a lot at 0.21 eccentricity)* and surface temperature ranges from about -180 deg C (night at pole) to about +430 deg C (noon at the equator). Venus 108 million km from Sun (i.e. gets a quarter of the sunlight that Mercury does). Surface temperature quite uniform day/night pole/equator at about 460 deg C. Remind me what the physical difference between Mercury and Venus is? Oh yes. Venus has an atmosphere. And what is the major constituent of the cytherean** atmosphere? Go on, have a wild guess. *Whereas John will pull my comment if I speculate upon that of the questioner. ** I learned so much from Kuttner/Moore. -
citizenschallenge at 18:50 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
Thanks for the information. {ps. you mean watt$ not sharing all of the story... go figure.} -
Bern at 18:31 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
Well, the obvious reply is that the earth's orbit *is* decaying, but very, very slowly - it's not likely to be a problem for at least half a billion years or so, I'd guess (to pluck a number out of the air - anyone who feels like doing the research will quickly be able to find something more meaningful). However, it's a constant process. Even if there *was* any significant forcing as a result of orbital decay, it certainly couldn't explain the rapid upswing in the warming trend over the past decades... And that, of course, completely ignores the circularity of his reasoning: "The earth is warming because it's orbit is decaying, and we know the orbit is decaying because the earth is warming..." -
stefaan at 18:22 PM on 17 December 2010Debunking this skeptic myth is left as an exercise to the reader
Hi John, To my opinion, two opposite factors will influence the distance earth/sun. First : the sun is becomming bigger due to the mass loss with about 4 % every 1 billion year (*wiki). So if the earth would keep the same orbit, the surface of the sun would be closer of course. However, there is a second effect, the equilibrium between the centripetal force (mv*v/r) and the gravitational force (Gm1m2/r*r). So if the mass of the sun is becoming smaller, the gravitational force decreases which will induce a larger orbit (to decrease the centripetal force). Of course the latter can also be achieved by reducing the speed of the earth but i think that that is very easy to verify. -
muoncounter at 16:41 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#10: "at the AGU meeting" Nope, sitting around the house watching Congress not do anything about everything. But a beer sounds good. One correction to the prior comments - Kerr did not give a talk, he wrote about one. Selective reporting, which was picked up in watt$world with their usual cherrypicking skills. So back to citizenchallenge in #6, the game's not poker; its Go Fish! -
hfranzen at 16:13 PM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
I don't think we are so very far apart. Since I am not familiar with the influence of biological activity I can only learn from what you present. Since I am considering the situation when the CO2 in the air and water phases are very close to equilibrium it is clear that I cannot deal with the situation in which photosynthesis is faster than diffusion. I don't understand what you mean by carbonate dissociating. I think that must be a "slip of the tongue". A point that I have been trying to make is that if the hydroxide ion concentration, the bicarbonate ion concentration, and twice the carbonate ion concentration re summed and then the hydrogen ion concentration is subtracted the result is far from zero - it is in fact, quite close to the bicarbonate ion concentration, a fact that is immediately apparent when one recognizes that bicarbonate is the most important species in the solution. It is by a large factor more importamt than hyrogen at the nominal pH of sea water of 8.1 plus or minus. The exact value is not important to the argument, just the fact that the concentration is much lower than the bicarbonate concentration. The significance of this apparent charge imbalance is that the majority of the carbon dioxide present in the three solute species cannot have arrived in the oceans from the atmosphere for if it had these charges would balance, but it has to have come in from another source such as from the worlds rivers as dissolved strong electrolyte (I would say dissolved calcium bicarbonate and carbonate, but of course there is no way to associate the ions anions and cations in a strong electrolyte solution. The important fact is that of the myriad of cations in the ocean some came in with the bicarbonate (and, to a lesser extent the carbonate). These must be in the sea and they do not, of course, exchange with the gas phase. Here is my main point: any attempt to consider the inorganic chemistry of the carbon bearing species must be made recognizing the existence of the cationic charge that balanced the bicarbonate and carbonate when they entered the sea. For this reason there is a restraint on the concentrations of the ions - they are subject to the restraint that the sum that I listed above plus the balancing cationic charge that entered the oceans with them is zero and unchanging. This restraint is an equation on a par with the equlibrium constants - i.e. there are 4 equilibrium constants and the charge balance equation fixing the concentrations of hydrogen ion, hydroxide ion, bicrbonate ion, carbonate ion, dissolved CO2 and the partial pressure of CO2(g) when one of these is fixed. Where you say, "and carbonate (sic) and bicarbonate must dissociate to reestablish equilibrium" I would say, "and bicarboante must dissociate to reestablish equilibrium subject the the restraint of the charge balance equation". I cannot agree with your statements in the paragraph that starts, "Based on 104". All that is required for transport is: 1.as the result of a temperature increase at point A the CO2 partial pressure is increased with loss of dissolved CO2 from the ocean owing to the endothermicity of the reaction forming CO2(g) from CO2(aq) 2. the partial pressure in this parcel of air is then at this time greater than the average value, 3. thus when the parcel arrives at point B, if its temperature was not increased by the same amount the chemical potential of CO2 in the gas phase will be greater than that in the water solution and some CO2 will dissolve. Thus some CO2 is transported from A to B. When the temperatures seasonally revert to their original values the process will be reversed, hence a cycle results. My problem with the 300 GT cycle is, if what I suggest is a correct interpretaton of the transport, as follows: I can calculate the increase in pressure at point A if T increases by ten degrees - it is 0.000091 bar. I can then calculate, using the ideal gas law, the volume that 300 GT of the released gas would occupy at the median temperature- the result is eight time 10 to to the 19 cubic meters. I can now calculate, again using the ideal gas law, the number of moles of air in this volume at 1 bar and 300K - the answer is 3 times ten to the 21 moles. But there are only 1.88 times ten to the 20 moles of air in the whole atmosphere. Of course there is nothing to say that the same air doesn,t circle back many times, but the amount of air required is absurd. The point here is that 300 GT of CO2 is an enourmous amount of CO2 and it would take an unbelievable amount of air to move it. -
Tom Dayton at 15:07 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
muoncounter, I'm inferring that you are at the AGU meeting. I'm jealous! I went last year, though spent considerable time being a booth babe. Had out of town obligations this year. If you go next year, let's meet for beer! -
Karamanski at 14:21 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
Could the recent sea ice deficit in Hudson Bay and in Baffin Bay be behind the current Greenland block weather pattern bringing cold weather here in the American Midwest? The past three winters have been colder and snowier than normal in the Midwest. Is it likely that warming in Greenland and the rest of the Arctic be the cause of the recent trend towards colder and snowier winters in the Midwest?Moderator Response: [Daniel Bailey] The reduced sea ice is probably more of a function of warmer sea surface temperatures. The blocking patterning of which you speak is also probably helping retard the ice formation by keeping out polar air masses. RealClimate has a timely post on that very situation here. There is some evidence, gaining clarity, that some of these "different" weather events, once rare, may become more frequent in a (supposedly) warming world as atmospheric patterns reorganize to a different regime. -
muoncounter at 13:38 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#6: "Galloping Glaciers of Greenland" Actually the call was during the same meeting as Kerr's talk. Khan et al 2009: We analyze data from continuous Global Positioning System (GPS) receivers located around the edge of the Greenland Ice sheet. ... Our results show huge uplift in southeast Greenland due to mass loss from the main outlet glaciers in the region. The signal is also picked up by GRACE as a huge mass loss in the same region. Additionally, our GPS results show acceleration of uplift in northwest Greenland starting around 2006-2007. This appears to provide on-the-ground confirmation of the GRACE interpretations. So unless Kerr is ready to go all-in, he'd better fold 'em. -
muoncounter at 13:20 PM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#6: "Galloping Glaciers of Greenland" Here's one from this year's meeting. Not a rebuttal of Kerr, but if this was poker, his bet is called. Krabill et al 2010 Repeat airborne laser surveys of the glacier were begun in 1993 ...and continue under NASA's ongoing IceBridge program. ATM and ICESat (2003-2009) observations quantify the spreading of the region that is thinning and the volume of ice loss. Coincident acceleration of the icestream suggests a dynamic mechanism to the thinning as the icestream draws in greater quantities of ice... demonstrates thinning near the glacier snout continues at about the same rate since 1997, while further inland thinning has accelerated. -- emphasis added -
Stephen Baines at 11:35 AM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
Somebody...tell me that makes sense. I'm not sure I can do better! -
Stephen Baines at 11:22 AM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
hpfranzen 104 is clearer than 102, and I largely agree with it except that you are still underplaying the role of biology. I'll address some quotes from 102 post keeping your clarifications in 104 in mind. "The ionic equilibria are independent of any organic phenomena." I'm not sure but I think you've getting caught up in a minor caveat I made for the sake of completeness. Dissolved organic matter can definitely affect the ionic charge balance because it is abundant, acidic and usually have a negative charge. Equilibria between cations and ions in solution must obey charge balance, that includes carbonate and bicarbonate. In dilute systems this can pose a problem. However, DOM is less of an issue in marine systems because the high salinity of seawater swamps the effect of dissolved organic matter. I think we agree on that so lets leave that aside. "Your statement that organic matter can pose problems for analytical solutions is correct only if the organic matter is affecting the concentration of disolved CO2 faster than the ionic eqilibrations can respond which is vary hard for me to believe. " I don’t think you are thinking of the same mechanism I am. Biological uptake of CO2 via photosynthesis only needs to be faster than diffusion of CO2 across the surface to affect the carbonate equilibria. When that happens aqueous CO2/carbonic acid decreases and bicarbonate and carbonate must dissociate to reestablish equilibrium between the carbon species. That dissociation consumes protons and raises pH. The increase in pH and alkalinity (and decrease in pCO2 and DIC) resulting from photosythesis is routinely measured and can be used to infer net CO2 uptake by photosynthesis. Because the water is now undersaturated with CO2 relative to the atmosphere, net flux of CO2 is into the water. If photosynthesis stops, eventually the carbonate equilibria will restablish its initial equilibrium as CO2 ingresses and the atmosphere and ocean come back into equilibrium. If the all the organic matter produced by photosynthesis is respired to CO2 again, the whole process happens in reverse and no net CO2 exchange happens. If the organic matter sinks to depths that do not exchange with the atmosphere, or if the water sinks to depth due to downwelling, there is a net removal of CO2 from the atmosphere, and DIC from surface waters.. "What you say about the southern latitudes having "to see that higher partial pressures occur" is wrong. All that is needed is for the atmosphere to circulate, which as I am sure you know it does, carrying the CO2-rich air to the CO2-poor region." Based on 104, I think we can agree that for net CO2 flux into the ocean to occur, waters must be undersaturated with CO2 relative to the atmosphere above those waters, right? So, for CO2 released by seasonal warming at high latitudes to be absorbed by warmer less seasonal tropical waters, the seasonal warming of high latitude waters would have to cause the CO2 concentration in the atmosphere above those tropical waters to increase in summer, resulting in a similar increase (though possibly lagged) above tropical waters. Only that way would a gradient in chemical potential exist that could drive CO2 influx. Unfortunately, the data I linked to shows little evidence of such a seasonal cycle in the southern hemisphere where the ocean dominates the earths surface area. The northern hemisphere does show a seasonal cycle, but it is timed to accrual of terrestrial biomass during the northern hemisphere spring and yields the opposite seaonal pattern you predict (low pCO2 as northern waters warm in spring). The lack of the predicted pattern results from a number of causes, but the main one is that increased biological uptake of CO2 in spring/summer counterbalances the effect of increasing temperature to a large degree by decreasing pCO2 in surface waters. To the degree that release of CO2 does occur due to warming at high latitudes (and it does in places), it is too small to register as a strong enough signal to drive influx in the tropics. FWIW...I think you are engaged in a fine but difficult activity. I just want to make sure you're not misled. I suggest reading chapter on the carbon cycle in Sarmiento and Grubers Ocean Biogeochemical Dynamics. Your probably easily advanced enough to understand it and we can only go so far here. -
citizenschallenge at 11:18 AM on 17 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
Thank you Daniel for that excellent detailed understandable description of the state of the knowledge regarding Greenland and glacial dynamics. John Cook and his gang that could shoot straight ! - you folks are really making a difference, at least in the availability of focused science information for the layperson, I sure do appreciate it. ~ ~ ~ I have a question - Can someone address the latest thing reverberating around the AGWHoaxer's Echo-chamber: Science 23 January 2009: Vol. 323. no. 5913, p. 458 FALL MEETING OF THE AMERICAN GEOPHYSICAL UNION: Galloping Glaciers of Greenland Have Reined Themselves In Richard A. Kerr Ice loss in Greenland has had some climatologists speculating that global warming might have brought on a scary new regime of wildly heightened ice loss and an ever-faster rise in sea level. But glaciologists reported at the American Geophysical Union meeting that Greenland ice’s Armageddon has come to an end." ~ ~ ~ I cannot find any critique on Kerr's study, any information would be appreciated. peter m -
scaddenp at 10:36 AM on 17 December 2010Global cooling: the new kid on the block
Henry, before continuing with idea that reduced sun is going to cause global cooling, please state why you disagree with the conclusion of Feulner and Rahmstorf (2010) -
muoncounter at 10:22 AM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
#105: "don't see any way around that - the data used fit observed laboratory spectra" And the higher temperature gradients are derived from observed temperatures. Here is a graphic from the Temperature record reliability thread.
The vertical scale is degC/decade.
However, since your model is determined (if I read it correctly) by ocean-CO2 interaction, perhaps it is significant that the rate of change you calculate agrees with the rates shown for oceans only.
-
Henry justice at 09:49 AM on 17 December 2010Global cooling: the new kid on the block
This site needs updating in light of the greatly reduced sunspots of Solar Cycle 24. It appears now to be a repeat Dalton minimum with overtones of morphing into a new Maunder minimum if the sunspots flat lines out after 2015. Some believe we are in for several decades of global cooling. Will global cooling or anthropogenic global warming become more pronounced as the years roll forward?Moderator Response: Henry, you've already posted a very similar comment in the thread What would happen if the sun fell to Maunder Minimum levels?. Quite a few people have replied to your comment over there. Please keep discussions of a hypothetical future Dalton/Maunder Minimum confined to that thread. -
hfranzen at 09:05 AM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
muoncounter: thabk you for looking at my website! I take what you say to mean thst the forcing is lower than you would like. I don't see any way around that - the data used fit observed laboratory spectra and the calculation does not allow any wiggle room. It is juat plain hard science. But I think anyone who's heart is warmed by a 1.4 degree per hundred year forcing is not vary smart! After all we are dealing with a century of ca, 1 deg forcing right now - is anyone happy with the curreht rates of change in our environment. At any rate I did this because there are those whose denial takes the form, "it's not happening" and to my way of thinking it is useful to be able to confront them with what I consider hard facts and rigorous logic as opposed to conjecture and statistics. By demonstrating that the warming we are experiencing right now is almost exactly predictable using undergraduate chenistry and physics I think I strengthen the hand of the climatologists who can then go on, hopefully, to convince deniers that in the future feedbacks are likely and potentially catastrophic. -
hfranzen at 07:03 AM on 17 December 2010Human CO2 is a tiny % of CO2 emissions
I feel the need to put my comments above in perspective. There is for carbon dioxide (or any other chamical species) a given chemical potential at a given T,P and chemical composition. In every cirumstance if there are two phases at a given temperature and applied pressure (ocean and air at some point on the surface, for example) the species will tend to go from phase 1 to phase 2 if and only if the chamical potential is greater in phase 1 than it is in phase 2. In terms of the oceans and the atmosphere the chemical potentials of carbon dioxide in the two phases are, to a very good approximation, given by (not equal to, but functions of at the given T an P) the partial pressure of CO2 in the air and the molality of CO2 in the water. When at equilibrium the chemical potantials are equal The chamical potential of the CO2 in the ocean could be influenced by the present of other dissolved substances. I am asserting, and my experience leads me to believe that it is a correct assertion, that the chemical potential of the CO2 is not significantly influenced by the presence of dissolved organic species at the level at which they occur in the ocean and is certinly not influenced by living organisms. what do I mean by significantly? A plus or minus 50% error would lead to the same conclusions that I reach, and I would be very surprised if the calculated molalities are off by even 1% because of organic solute species. I believe this assertion to be true for carbonate and bicarbonate as well. For this reason I claim that the equilibria of these inorganic species are independent of life processes and the resultant organic matter in the oceans. Because they carry a charge their The chemical potentials of ionic species,because they carry a charge, are influnced by dissolved salts, and in my calculations I include this influence using the Debye-Hueckel Law. This calculation is actually going to extremes to try to get the best result possible - the argument here is basically about the tendency (spontaneous direction) for chemical reactions and does not depend upon the actual molalities but rather upon the change in reaction direction with increasing and decreasing temperature and basic thermodyanamics. That is, it is a rquirement of thermodynamics that in order for CO2 to pass from the ocean to the atmosphere it is necessary that the chemical potential of CO2 in the aqueous phase be greater than that in the solution phase. The deniers, by the wauy, miss this point entirely. Be that as it may, as the temperature of the system is seasonally increased the chemical potentials, which are equal at equilibrium, are unbalanced in the direction so that CO2 passes from the ocean into the atmosphere (the chemical potential of aqueous CO2 increases more rapidly with temperature than does that of the gaseous CO2). That higher chemical potental CO2 will move with the air mass, and when it comes to a place where the chemical potenial in the ocean is lower than it is in the atmosphere (i.e., at a point at which the temperature is lower than at the starting point) it will dissolve. Thus do we get transport in one direction. When the temperatures seasonally revert to their original values the processes reverse. Therefore a cycle. This is Physical Chemistry. I know nothing about the life processes in the ocean and their role and I am anxious to learn. But this I do know: what I have stated immediately above is thermodyamics plain and simple and unless something completely unknown is occrrring the organic natter and living organism are a red herring in the discussion of the ionic equilibria. So my question about charge balance is a highly relevant one - the ionic equilbria, which I agree do not tell the whole story because of biological processes but do none-the-less tell an independent story that cannot be denied without denying thermodynamics, can shift only in a manner consistent with electrical neutraliy. This in turn means that the way in which the deniers claim that CO2 comes out of the ocean in copious amounts is nonsense and the notion that 300 GT of carbon dioxide pass from one to another portion of the ocean in a year is highly suspect.Moderator Response: [Daniel Bailey] Please break long comments into paragraphs. The average human mind has difficulty in following statements beyond a certain length (3-4 sentences per paragraph is about the limit). You'll find more engagement as a result. -
scaddenp at 07:00 AM on 17 December 2010The 2nd law of thermodynamics and the greenhouse effect
Since any actual measurement agrees with textbook theory, I think that burden in on damorel to produce evidence of a measurement that disagrees. Of course this would also involve understanding what the textbook physics actually do predict rather than some imagined belief about the physics. -
muoncounter at 06:27 AM on 17 December 2010It's cooling
#84: "covered in meadows" Where have you heard that? If you are referring to the Medieval Warm Period, here is a map that shows Norse settlements of the period; I believe the large white area is ice and snow. And here is a more appropriate thread for further discussion of that subject. -
Ganesha at 06:22 AM on 17 December 2010The 2nd law of thermodynamics and the greenhouse effect
RE #259: damorbel at 03:54 AM on 17 December, 2010 Can you please clarify exactly what your point is? Are you complaining that people refer to the earth as a black body? - Isn't a black body a theoretical thing? - Does it help if you just read that as "grey body"? - How does your concern over the black body terminology impact the earth's emission of IR radiation? Are you suggesting that the earth doesn't emit IR? Honestly, I can't find what your point is. Just come out and state it.
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