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Tom Curtis at 16:35 PM on 24 June 2011Linking Extreme Weather and Global Warming
Norman @189, your are correct that there was a discrepancy, and my second post was exaggerated. Never-the-less, your practical definition of "disaster" is far too restricted, at least as used in your post 154. In particular, you say there where "3 tornado disasters", and that "In 2011 with 80 F3 or above tornadoes you have 6 tornadoes of this magnitude that caused disaters and a total of 9 tornadoes that struck cities". In fact in the 1974 outbreak there were tornado related deaths in 64 different counties, and nine "most significant" tornado incidents, Xena (death toll - 34), Brandenburg (31); Lousville (only 2 killed, but over 200 injured and 900 homes destroyed); De Pauw and Madison (17 killed, 375 injured); Cincinnati/Sayler Park (3 killed and over 100 injured); Monticello (19 killed); Tanner (50 killed, over 400 injured); Jasper, Guin and Huntsville (3 killed and over 150 injured); and Windsor, Canada (9 killed, 20 injured). So, my first point is that in counting only three tornado disasters in 1974, you are using far too high a standard for the damage/injury or death level needed to categorize a tornado as a natural disaster. Actually, in the Munich Re data the entire outbreak and all its tornadoes may well count as just one disaster, and the many seperate outbreaks in 2011 also each count as one disaster regardless of the number of tornadoes spawned in each outbreak. But ignoring that subtlety, there where at least nine, and probably more than 30 distinct disasters in that one outbreak. (Some tornadoes crossed more than one county, and one crossed three states, so I cannot give an exact count.) My second point is that each of the three most deadly tornadoes listed above was an F5, and nearly all were F4 or F5, with only the Windsor tornado being F3. Therefore the F3 tornadoes are irrelevant to the comparison you actually made. Note carefully, irrelevant for the comparison, and most certainly not irrelevant on the ground. So if you only wish to count the three worst incidents in 1974, then you should restrict the discussion to F4 plus tornadoes, and in that case 1974 and 2011 have very similar numbers. What is more, in 2011 just two tornadoes caused thirty or more deaths, your apparent benchmark for significance in 1974. So, while I acknowledge and apologize for my error in post 164, I believe my logical points stands unrebutted -
ginckgo at 15:58 PM on 24 June 2011The chief troupier: the follies of Mr Monckton
beastie @ 5: The majority of the world's coal deposits were formed during the Late Carboniferous (Pennsylvanian) and Early Permian. During these periods the atmospheric CO2 content was about what it is today, and the world was in the longest Ice Age of the Phanerozoic. How does that reconcile with the assertion that during high CO2 times plant productivity will be higher, when we have this geological evidence that appears to indicated the opposite is true (there are more factors than CO2 involved, obviously). Petroleum on the other hand often comes from source rocks that were laid down in Greenhouse climates; but these are all marine sediments, and the organic content preserved so well because the oceans were stagnant and huge dead zones covered the ocean floor allowing the carbon to accumulate (but that's not a happy ocean from our perspective). -
R. Gates at 15:36 PM on 24 June 2011The Last Interglacial - An Analogue for the Future?
This will be an interesting series to follow. A few thoughts: While it is interesting to compare two different interglacials, and certainly both can be traced back ultimately to Milankovitch cycles, I would think that comparing CO2 levels and anticipated effects might yield some very sketchy projections. Rising temps during interglacials probably begin a positive feedback process with outgassing of CO2 from the oceans leading to more warming etc., but the sudden anthropogenic burst of CO2 during this interglacial to far higher levels than the past several interglacials should create a completely different dynamic, as the ocean themselves have not warmed enough to have released a similar amount of CO2...i.e. we are heading closer to what we saw in CO2 levels during the PETM but ocean temps are currently cooler. So, as oceans warm and begin to become net producers of CO2 from outgasssing rather than the large CO2 sink they been, it's possible we could see a sudden jump in the annual rate of CO2 growth, far larger than the annual increase from anthropogenic sources alone. This would be a far different dynamic than the last interglacial and would likely lead to all sorts of other very different climate dynamics. I certainly look forward to the rest of this series... -
okatiniko at 15:24 PM on 24 June 2011Sea Level Hockey Stick
#39 : "@okatiniko. What do you mean? without any clear signal...? Can it be any clearer? " The signal is very clear after 1900, but there is nothing conspicuous associated with the supposed anthropogenic component after the 60's. This is very usual in all proxy-based reconstructions : they don't show anything clearly associated with the rise of anthropogenic forcings, only with the exit from LIA in the XIXth century - or maybe simply correlated with the advent of modern instrumental methods, allowing the proper calibration of data. There may be explanations for that, but perhaps not of the kind you'd like to hear.Response:[DB] "There may be explanations for that, but perhaps not of the kind you'd like to hear."
If, as I suspect, those "explanations" run afoul of the Comments Policy, then you would be correct.
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Camburn at 14:53 PM on 24 June 2011Linking Extreme Weather and Global Warming
DB: On this one I have to disagree. Where I live, ND, when we have a mild winter we, as a rule, have less snow. This past winter was the 13th coldest on record, and if memory serves me, the 6th snowiest on record. We can have -20F temps, then the temp rises and it will snow. After the front has passed, it will cool off again to the normal cold. A local observation of what happens here. -
J. Bob at 14:47 PM on 24 June 2011Sea Level Hockey Stick
Sphaerica @49, Perhaps you didn’t get the point. The initial point was to compare tidal measurements on the E & S coasts of the US, with global temperature. That is, get a broader surface sample of readings. Then compare the filtered results to see if there is any significant correlation. And from the graph, it was found that the station data was pretty close to the trend line, and did not have the changes ( i.e amplitude and/or phase), noted on the global temperature plot. That just might give a indication of temp & sea levels not being correlated that well. ( -Previously posted linked graphic snipped- ) The second was a matter of interest, as to NH temperature being correlated to long term temperature records. Since the issue of conflating regional data to global data came up, here is a updated chart comparing long term European data with HadCRUT NH & global data. It would appear there are strong correlations between the temperatures, but not with the CO2, similar to the tidal data. ( -Previously posted linked graphic snipped- ) And I will agree, there can be problems with conflating information, one has to be careful on what your doing. So one can make the case that a correlation between sea level an global temperatures is about as bad as between global temperature and CO2. Perhaps you could "cobble" something better, to convince me otherwise?Response:[DB] Links to graphics you had previously linked to in your comment at 48 earlier snipped. Please just refer back to the earlier post with a link to it. Repeating yourself doesn't gain you extra credit.
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scaddenp at 14:41 PM on 24 June 2011Sea Level Hockey Stick
If you made some effort to understand the link between regional and global sealevel, you would make more sense. Hint the "10cm error bar" doesnt mean what you think it does. -
Camburn at 14:29 PM on 24 June 2011Linking Extreme Weather and Global Warming
Must be a difference in the climate. Whenever it snows here in the dead of winter it always warms as it snows and then gets colder again. That is about the only reason to look forward to snow as the temp moderates.Response:[DB] "Whenever it snows here in the dead of winter it always warms as it snows and then gets colder again."
That's because here in the north where we live the snowfall event is usually quickly followed by very cold Arctic air masses that move down out of Canada. Clear skies at night allow the warmer air held nearer the ground by the clouds delivering the snowfall to then escape, leaving the surface air much colder than it was previously.
Which is why there is less precipitation in the colder winters and more in the warmer winters here.
This is all very basic, basic stuff.
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Camburn at 14:27 PM on 24 June 2011Linking Extreme Weather and Global Warming
Yes scaddenp, I am complaining about the management. In 1953 there was more water with way less devestation. -
Camburn at 14:25 PM on 24 June 2011Sea Level Hockey Stick
Ok......10cm error bounds. Sea level is rising at approx 2.3mm per year. So with normal stats, 10CM error bar....that means that sea level could stay flat somewhere for approx 90 years and be within the error bars. Yep....this regional rate is certainly global. I am actually surprised that anyone is trying to project this regional rise to a global scale. As I said, this tail doesn't wag.Response:[DB] "that means that sea level could stay flat somewhere for approx 90 years and be within the error bars."
And by what physical processes would that be happening under? Given the SLR already documented to be in the pipeline?
You grasp at leprechaun straws.
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dhogaza at 14:11 PM on 24 June 2011Sea Level Hockey Stick
Regional is regional. One can gloss regional to try and make it global but the dogs tail isn't wagging.
Correlation within 10CM error bounds. On the one hand we have mathematics ... On the other hand, Camburn's perpetually wagging tongue that proclaims his bias trumps analysis ... no matter how often he's been shown to be full of it. Tch, tch. -
scaddenp at 14:07 PM on 24 June 2011Linking Extreme Weather and Global Warming
You are complaining about the management of a flood - the climate question is about whether there is a trend in the frequency of extreme events. Never noticed that warmth when it snows here - only in the northerly that usually proceeds it. -
Camburn at 14:04 PM on 24 June 2011Sea Level Hockey Stick
KR: Proxy switch at 1,000 AD. The reason for the proxy switch is the data didn't match. That is just one item. And there are large differences in sea level world wide. Even differences in sea level rise rate. Regional is regional. One can gloss regional to try and make it global but the dogs tail isn't wagging.Response:[DB] "Proxy switch at 1,000 AD."
What proxy was switched for what, specifically?
"The reason for the proxy switch is the data didn't match."
In what way? Are you implying fraud on the part of the authors?
"And there are large differences in sea level world wide."
No, not really.
"Even differences in sea level rise rate."
Yes, for very-well-documented, non-handwaving reasons. One can even try and liken it to the tail wagging the dog all one likes, but that just demonstrates you have no argument supported by the science.
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Camburn at 14:01 PM on 24 June 2011Linking Extreme Weather and Global Warming
scaddenp: Actually, snow brings warmth. After it snows, it gets colder again. -
Camburn at 13:56 PM on 24 June 2011Linking Extreme Weather and Global Warming
michael sweet@184: The reason that Minot is flooding so badly is the total ineptness of the Corp of Engineers and the Canadian authorities. Minot would have been much better off if the dams had not been in place. The flow rate was kept low with the idea of more rentention. Well, the dams are now full and the discharge is now in addition to the flow. It is a super duper mess. I live in ND and have been watching this happen and just shake my head in anger. Same with Bismarck and the Missouri River. Garrison SHOULD have been allowed to be drawn down. The fish and wildlife put the stops to that even tho we KNEW the snowpack was 138% of normal. And we KNEW from long term forcasts that it would be wet. NOAA has been predicting this for months on end as this is the normal effect of La Nina. ANOTHER case of veryyyyyyy poor management. Stream flow rates show that the Missouri would be lower today if there were NO damns. Same with the Souris in Minot. They held the water back.....dumbbbbbbbbbb.Response:[DB] Please refrain from all-caps usage.
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Stevo at 13:54 PM on 24 June 2011The chief troupier: the follies of Mr Monckton
Albatross @ 19 After viewing those 2 files you linked to I'm almost tempted to use one of Monkton's own tactics against him and say, "Mr Monkton might be on record for spreading lies, mistruths and personal attacks against those he cannot overcome by means of scientific argument but has privately indicated that he has changed his position and regrets his past performances". -
scaddenp at 13:47 PM on 24 June 2011Linking Extreme Weather and Global Warming
Since Kundzewicz was the work cited in AR4 on flooding events, I looked for more recent work. Anyone seen Kundzewicz et al, 2010? -
Patrick 027 at 13:42 PM on 24 June 2011The Planetary Greenhouse Engine Revisited
... also, ozone itself can emit radiation somewhere around 10 microns wavelength. -
bill4344 at 13:34 PM on 24 June 2011The chief troupier: the follies of Mr Monckton
Thanks to Albatross @ 19 for the links; I feel I have to quote here this particular gem -Yes, we are now probably seeing more deaths rising from the behaviour of the Hitler Youth, and, more sinisterly, the people who are behind them and paying for them and indoctrinating them - those are the ones we really need to track down and root-out and shove in gaol for the rest of their nasty little lives - because we are killing people probably in larger numbers now than Hitler did when he killed the Jews.
This from 2009. Shortly before his first tilt around Australia, as heavily promoted by... Jo Nova! So it's not like he's only recently descended to this; during the intervening period he's been a darling of the deniers, feted at WUWT, flown all over the world on some 'interesting' expense accounts, met by Abbott in full dog-whistling-for-the-maddies mode, etc.. And, yes, what many - perhaps most - of them are now condemning is his lapse in taste! Truly, satire is redundant. -
Bibliovermis at 13:31 PM on 24 June 2011IPCC Report on Renewable Energy
Unlike nuclear, wind & solar do not require exclusive use of the land. -
quokka at 13:16 PM on 24 June 2011IPCC Report on Renewable Energy
#49 Marcus Let's get one thing straight - I am not arguing that subsidies are a good thing or for that matter that in all cases they are necessarily a bad thing. These are complex issues and require careful analysis. But to argue that cost differentials in energy technologies is principally due to subsidies is extremely dubious. Furthermore, to come to any specific conclusion on decarbonization effects based on past expenditure on subsidies is folly. That is sunk cost, what matters today and in the coming decades is current and future costs. There are many reasons for cost differentials and some of them are based in physical reality. One physical reality is energy density. This is one reason I believe that some renewables can never be as cheap as chips. Wind and CSP need lots of materials - steel concrete etc - and a lot of land. A lot more than for example does nuclear - by an order of magnitude or more. This is no going to change. Trivializing energy analysis with a blind belief that infinite subsidies can, as if by magic, and by a wave of the hand dismiss physical and engineering realities is not going to get us a long way. It is much more complex than that. -
Tom Curtis at 13:08 PM on 24 June 2011Linking Extreme Weather and Global Warming
Norman @186, I freely admit that Munich Re have a financial interest at stake. Increased global warming will result in increased losses due to pay outs, so that if nothing is done, insurance companies will bear much of the cost of the negative externalities that fossil fuel companies do not bear. However, as Munich Re include summaries of this information in their share holder reports; and as misleading shareholders is a criminal offence (at least in Australia); I am really wondering if you have any evidence on which you base your charge of criminal misconduct. Or are accusations of criminal misconduct standard fare for fobbing of information you do not like in your circles? -
KR at 13:08 PM on 24 June 2011Sea Level Hockey Stick
Ken Lambert - 'Surely quotation of the North Carolina Sea Level which is the subject of this thread is also a case of "conflating regional data to global data". ' Not if it's properly corrected for local isostatic rebound adjustments. Unlike absolute temperatures, sea levels have very little variance around the world. Do you have any specific issues with the adjustment and calibration procedures included in Kemp et al 2011? As in particulars you can identify as errors? I've asked that question on several blogs, with no answer so far. --- Incidentally, this very paper is currently a hot topic on both JoNova and WTF'sUST. With predictable insults about data availability, North Carolina sedimentation rates, and basic handwaving, and absolutely no concrete addressing of the techniques described in the paper. Oh, and a lot of Ad Hominem attacks on Michael Mann being involved, even though he's the 4th author of 6... -
scaddenp at 12:57 PM on 24 June 2011Linking Extreme Weather and Global Warming
Norman, I fail to understand why the links you offer contradict the position. This is again a concentration on proximate causes. Try this logic: 1/ Warmer world gives you wetter air mass. Agreed? 2/ If wet air mass cools it will precipitate. 3/ If the temperature drops below zero, then this precipitation will fail as snow. Furthermore, if a cool air mass moves over a country, and then drops snow out of because of contact with wet mass, then the snow will result in colder surface temperatures. On the good news front - the line between where you get snow or not in winter should move poleward (probably way too early to tell). And spring will come earlier. (plenty of data for that). -
Norman at 12:55 PM on 24 June 2011Linking Extreme Weather and Global Warming
Tom Curtis @ 164 Material from an ealier post of yours 141 "A disaster is defined as a serious disruption of the functioning of society, causing widespread human, material or environmental losses, which exceed the ability of an affected society to cope using only its own resources (EEA 2006). The extent of the disaster depends on both the intensity of the hazard event and the degree of vulnerability of the society. For example a powerful earthquake in an unpopulated area is not a disaster, while a weak earthquake which hits an urban area with buildings not constructed to withstand earthquakes, can cause great misery (GTZ 2001, p. 14)." Now in 164 you state "In fact, it is not even based on a correct use of the definition. For a hazard to be classified as a disaster, it need harm only a single human being or their property. An EF0 tornado that blows ripe apples to the ground in a orchard thereby becomes a "disaster" and, if reported, will be recorded as such in the Munich Re chart." I don't think the two post are in coherent agreement with each other. Also why do you neglect the damage done by an F3 in your critique of my analysis. There were many more potential disaterous tornadoes in 1974 than in 2011 yet 2011 had a larger number of disasters. F3 tornado does cause a disaster when it hits a populated area.Patrick 027 at 12:41 PM on 24 June 2011The Planetary Greenhouse Engine Revisited
... of course that assumes a LW blackbody surface. With sufficient LW albedo at the surface, I think adding GHGs could at first cause some surface cooling, but eventually adding more would cause warming. ---- Going back to an earlier point: I had (roughly) estimated a mean free path for photons near the peak of the CO2 band to be about 1 m (see Real Climate comments) (setting aside variations over height in line broadenning and line strenghth). But this is a narrow peak; I think the mean free path may only be about 100 m or less over a band width of ~ one micron, though this is a rough estimate. Anyway, the density in the mesosphere is roughly 1/1000 to 1/100000 of the surface value, and (setting aside variations over height in line broadenning and line strenghth), this implies photon mean free paths on the order of 1 km to 100 km at the peak and less than or about the same as 100 km to 10000 km over a band width of about a micron. The temperature gradient of the mesosphere is considerably less than a dry adiabatic lapse rate - I graphically estimated 2.8 K/km for the steepest part of the profile in a CRC handbook of Chemistry and Physics graph - 3.8 K/km for an older profile in the same graph; whereas the troposphere had around 6.4 K/km, which is typical for a moist adiabatic lapse rate there). I think about 3 % of incident solar radiation (~ 342 W/m2) is absorbed by the ozone layer - that's about 10 W/m2 solar heating, distributed over more than a 10 km thick layer, including down into the stratopshere where photon mean free paths are smaller. The temperature at the stratopause gets up to around 270 K, where at 15 microns the blackbody flux is almost 15 W/m2 per micron bandwidth (it's 7 W/m2 per micron at 225 K). While I haven't completed the analysis, it seems like radiation within the CO2 band should have little trouble responding to the temperature gradients here (going farther down into the atmosphere, when the center part of the band is too thick, you can find intermediate opacity farther out from the band center). Over sufficiently thick layers, water vapor can also contribute (it is on the order of unit optical thickness for the whole upper atmopshere in the most optically thick portionss of the water vapor spectrum).Ciccio at 12:38 PM on 24 June 2011Maize harvest to shrink under Global Warming
With all the arguments there is one factor that seems to have been most carefully ignored, the one that has more impact than any other. Population 1960-2010-2050 projected. Southern Africa: 19 - 64 - 106 million Western Africa: 80 - 315 - 638 million There have been changes in the past and it is well possible that the same science and technology that has extended life and survival is now causing more changes but the biggest change of all is this vastly increased human burden.Norman at 12:35 PM on 24 June 2011Linking Extreme Weather and Global Warming
michael sweet @ 184 Do you have an explanation that ties this flooding in with a warming planet? If you choose see my link above "Explanation for Heavy snowfall in winter of 2010" Can you find data similar to this that would show why a warmer globe triggered the heavy rains in that area that are responsible for this flooding in Minot?Norman at 12:32 PM on 24 June 2011Linking Extreme Weather and Global Warming
Albatross @ 147 "Stanley Chagnon is your man and Google is your friend. " I did look up the study performed by Stanley Chagnon. He found that warmer winters had a better chance for more snowfall events (but they did find no effect on the biggest snow events). I also followed your advice on using Google to come up with this information. Not an extensive study and not as complete as Stanley Chagnon's. Two links. Omaha Nebraska Winter snowfall accumulations. (I use Omaha since I live near this city) Explanation for Heavy snowfall in winter of 2010. You can see Omaha had 20" more snow than normal in the 2009-2010 winter. In the second link you can see that the temperatures of the United States were really cold during this snowfall period (18th coldest winter since records were taken). This would be a strong exception to the warmer temps lead to more snowfall concept. Also the second link gives a nice explanation for what produced the cold and excess snow of that winter and it can all be explained quite well without global warming being introduced. The pattern was predicted based upon previous events of similar nature.Riduna at 12:13 PM on 24 June 2011Sea Level Hockey Stick
While there is no doubt that sea level is rising, isn’t production of a hockey stick more dependent on the scale shown on the graph than the speed of SLR? As President Reagan noted “You aint seen nothing yet!” Just wait until the melting of polar ice sheets really gets underway. On 22 June the ABC reported http://mpegmedia.abc.net.au/rn/podcast/2011/06/bst_20110622_0636.mp3 temperatures in northern Greenland reached +30C which, if true, is astonishing evidence of Arctic amplification. Hansen et al 2011 predict that rising Arctic temperature will result in decadal doubling of ice loss from the Greenland ice sheet. If realised, it can be expected that present rate of loss ~250 Gt/annum will increase to loss of ~130,000 Gt in 2100 with most of that loss occurring after 2060. Now that will produce an indisputable hockey stick!Norman at 12:09 PM on 24 June 2011Linking Extreme Weather and Global Warming
Tom Curtis @ 165 Mr. Curtis, I forgot to ask you why you are using Munich Re as a source of acceptable information. They are not an unbiased group of scientists striving to reach the truth on this issue. Munich Re?. They are a huge multibillion dollar insurance company. They have a product they want to sell. Higher threat of disaster is a selling point. I hope you can find better sources to prove a connection between global warming and increased weather related disasters.Norman at 11:53 AM on 24 June 2011Linking Extreme Weather and Global Warming
scaddenp @ 183, I totally agree with your comment that an increase in bad storms will increase the probability of a disaster.Marcus at 11:52 AM on 24 June 2011IPCC Report on Renewable Energy
Well its actually really hard to tell from those graphs, Quokka, but I know that Australia's Fossil Fuel industry receives about $9.2 billion in Government Subsidies, & the US industry receives at *least* $40 billion in Federal Subsidies *alone* (don't know what it equates. If this is anything to go by, I'd guess its fair to say that close to half of the $560 billion in fossil fuel industry subsidies is being spent in OECD countries-like Germany, Australia, Japan, the UK & Canada. Even so, the fact that its the Developing Nations which are spending so much money subsidizing Fossil Fuels-rather than renewable energy-does not negate my argument that the only reason fossil fuels are so cheap is because of decades of tax-payer funded support. After all, if the industry is so mature, then they should be able to provide cheap energy in developing nations *without* the need for massive subsidies! My main point is that the whole "cheap" fossil fuels thing seems to be a major case of False Economy-especially when you consider that most renewable energy technologies have gotten within spitting distance of fossil fuels *without* the need for such costly subsidies!Ken Lambert at 11:44 AM on 24 June 2011Sea Level Hockey Stick
DB #48 "[DB] Your final linked graphic you have posted here repeatedly. And just as repeatedly, it has been pointed out the issues with conflating regional data to global data" Surely quotation of the North Carolina Sea Level which is the subject of this thread is also a case of "conflating regional data to global data".Eric the Red at 11:30 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Sky, If Greenland were to melt completely, it would take another ice age to regrow based on the altitiude of the current glacier. Based on previous evidence, this is unlikely to occur anyway. Sea ice can regenerate every year. Sea ice is governed by water temperature. It is reversible. Current trends show that the Arctic could be ice free in summer by 2050, however, winter sea ice is likely to remain for many centuries. ://chartsgraphs.files.wordpress.com/2010/10/nsidc_arctic_sie_max_min_melt_by_yr_snag_it_2.pngPatrick 027 at 11:26 AM on 24 June 2011The Planetary Greenhouse Engine Revisited
Of course, if you add a small concentrated region of solar heating, then there will be a temperature response with net LW flux divergence out of that region at relatively more opaque bands; but this will heat neighboring regions, so the larger region warms up so that a net LW flux can come out of that, at somewhat less opaque bands, etc. The process would continue until the additional net LW flux is escaping to space; this will require more 'steps' if the atmosphere as a whole (depending on spectral structure) is more opaque, and each of those steps added warmth, so the original affected region gets warmer (When the LW flux out of the solar heated region reaches a layer that can radiate where other layers are more transparent, the next step will have some of that LW flux travelling across thos transparent layers, and this may include escape to space). Alternatively if we are only rearranging solar heating (or rearranging it via convection), then the following approach may work to some extent: the changes in solar/convective heating could be represented by a linear sum of sinusoidal functions over mass path or some other convenient variable. Then the temperature response to each component would tend to first involve LW radiant net flux changes in those parts of the spectrum where the Planck function changes the most and where the optical thickness over ~ 1/4 of the wavelength of the heating distribution change is ~ 1 (or actually a bit less then 1 since radiation is travelling over all directions, not just vertically). For small changes one could find temperature responses for each component and add linearly, but for larger changes nonlinearities become important and so one would have to evaluate the temperature response for one component, then the next, etc. The radiation will be most responsive to temperature changes in spectral bands where the distances over which solar heating (or convective heating, etc.) are on the order of unit optical thickness, so there should be some tendency for the LW fluxes in these bands may largely determine the required temperature profile for equilibrium. Of course that depends on band width and where it is in the spectrum relative to the relevant Planck function(s). If the bands with optical thickness ~ 1 on the spatial scale involved, in the best part of the spectrum, are insufficient, the temperature response will be large enough to have significant effects on LW fluxes in bands with somewhat larger or smaller optical thicknesses or in less optimal parts of the spectrum, and if that isn't sufficient, even larger or smaller optical thicknesses or even less optimal parts of the spectrum will have significant net LW flux changes. -------- Starting with an atmosphere transparent to all radiation, adding a tiny amount of GHG will instantly bring the whole atmosphere's radiative equilibrium temperature to the skin temperature (for the spectrum involved); the atmosphere will be colder but as it can now emit radiation whereas before it could not, 'backradiation' increases at the surface and so the surface equilibrium temperature increases. If there is some solar heating of the air, adding a little GHG to a LW-transparent atmosphere reduces the equilibrium temperature profile of the atmosphere by allowing the atmosphere to emit radiation to help balance solar heating. Parts of the atmosphere still may remain warmer than the equillibrium surface temperature. As GHG concentration increases, the solar heating is effectively spread out over greater LW optical thickness, and the temperature at TOA will eventually come down toward a skin temperature (the effect of direct solar heating is in a sense 'diluted'), although within the atmosphere, increasing LW optical thickness can eventually start to trap solar heating in a layer and cause the temperature to increase.Bern at 11:26 AM on 24 June 2011The Last Interglacial - An Analogue for the Future?
Note: I just picked the January-December anomalies for 1950 & 2010 from the GISS data - obviously, you need to look at a longer-term average to make it meaningful...Bern at 11:25 AM on 24 June 2011The Last Interglacial - An Analogue for the Future?
That's the problem, Chris, not everyone understands what the baseline is. How much warming have we had since 1950? It's 0.79ºC, according to GISS J-D averages. That's quite significant, if you're referring to temperatures about a degree warmer than "today".Eric the Red at 11:20 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Since the volume of ice in Greenland is ~2.8 million cubic km, and the maximum current rate of loss is ~100 cubic km / year, that is many millenia before Greenland will melt. The IPCC predicted that it would take a 5.5C temperature rise to melt Greenland, and it would take several centuries. Recent studies show that the melt rate is significantly less. http://www.sciencepoles.org/news/news_detail/new_model_forecasts_slower_rate_for_greenland_ice_sheets_contribution_to_se/ http://www.sciencedaily.com/releases/2011/01/110126131538.htmChris Colose at 11:14 AM on 24 June 2011The Last Interglacial - An Analogue for the Future?
In paleoclimate literature "today" often means 1950, sometimes something else (just look at the papers). It's worth keeping in mind but it's really not worth fussing about the baseline as long as everyone understands it. Especially for the "larger" climate changes of the past, whether anomaly is computed relative to 2000 or 2011 makes virtually no difference, and is within reconstruction uncertanties anyway.Bern at 11:10 AM on 24 June 2011The chief troupier: the follies of Mr Monckton
Well said, Agnostic! Monckton, like many of the hard-core deniers, is very quick to resort to ad hominem attacks when his flimsy 'scientific' argument is shredded and proven to be false. 'Skeptics' like Ken Lambert in post #1 are quick to repeat the ad hom attacks and slurs on integrity, while also struggling to present any substantive criticism of the science. I do find it amusing, though, that 2 out of the 3 ad hom slurs in post #1 were fabricated by Andrew Bolt. Even just a few minutes spent googling will turn up enough evidence to demonstrate that.skywatcher at 11:01 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Reversing processes is not necessarily simple and linear - if the system exhibits hysteresis. An example is an ice sheet, whose height above sea level (and thus lateral extent) begins to decrease. This places a smaller area of the ice sheet above the snowline, encouraging subsequent decrease in snow accumulation. Continue this process and you can lose an ice sheet without continued warming. The height of the exposed land surface is now much lower than the surface of the original ice sheet. How do you make the snow hang around through the summer in such a way as to regrow the ice sheet? It's a bit more complicated than that (flow dynamics and precipitation changes complicate the picture somewhat), but this is what is at stake with both the Greenland and W Antarctic ice sheets. That's many metres of sea level. So. How do you grow back your ice sheet, Eric? On the thread topic, dark water absorbs more energy than white ice. More dark water surrounding the remains of a melting sea ice cap absorbs more energy and does not freeze quite as easily (and certainly not to the same thickness). Once the Arctic ice is gone... how do you grow back the reflective ice cap that is one key to current global temperatures, sea level (through cooling the GIS) and weather patterns? These things may be reversible (though you provide no evidence as to why), but certainly not in the short term once the hysteresis takes hold...Tom Curtis at 10:42 AM on 24 June 2011Sea Level Hockey Stick
Argus @58, over the geological long term, sediment is carried back out of the ocean either by subduction or by uplift which has turned former marine deposits into the Alps (for example). If it where not, over the long term the continents would have entirely disappeared under the sea by erosion, whereas over the 600 million years for which it can be determined they have remained approximately constant in total area (although having drifted around significantly, and formed a super continent twice). The survival of continents shows that over the long term net displacement of water by geological processes including erosion is zero. Having said that, the net displacement over any short period (ie, several millions of years) could be either slightly positive or negative. Currently Africa is moving north replacing shallow Mediterranian water with deep Antarctic Ocean water. Australia is also moving North, replacing shallow water with deep water. India continues to move North, enlarging the Indian Ocean, and I believe that South American continues to move towards North America, collapsing the the Caribbean. Meanwhile the Horn of Africa is separating from Africa, thus reducing the Indian Ocean. All these motions are at a rate of mm per year, but because of the large shorelines involved, all would result a greater displacement of sea water then the net displacement by sedimentation and subduction. What is the net effect? I don't know except that given historical sea water stands (ancient beaches etc) it is very close to zero, and well within the error bars of Kemp et al.michael sweet at 09:47 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Comments made without evidence can be dismissed without evidence. I have provided data to support my position. You have not. Until you provide data to support your position you are dismissed. Eric the Red is a (-Snip-) who should be banned since he refuses to provide data to support his positions and refuses to even read data provided to him that shows he is wrong.Response:[DB] Fixed html tag and snipped a bad-sounding word.
adelady at 09:45 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, reversing effects? It's a simple question. Just how many mountains (of suitable rock composition) are you prepared to blow up? Every year? Each year's CO2 production from oil alone equates to 93 million years of CO2 sequestration in those fossils. Unsurprisingly, natural geological sequestration is entirely unable to keep up with the release. If we want to "reverse" the many impacts of our accelerated geological CO2 releases, we'd better pay some attention to accelerating geological CO2 sequestration. That is, expose the maximum area of rock surfaces to air and water. Blow it up, reduce it to gravels and dust. Move on to the next one. If we can do it for coal, we can do it to counteract coal. I know many people believe we can do it with biological sequestration alone. We could do it that way. If we could ensure nil deforestation as well as universal adoption of soil carbon retaining practices, it could be done. I have no confidence that anyone or anything on earth will ever restrain the logging companies in the Pacific region, let alone worldwide. So. How many mountains per year?Eric the Red at 09:37 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
Several meters, wow! And you thought my post was outrageous. I guess I can dismiss that one. CO2 will not stay in the atmosphere forever. If we were to stop emitting today, the level would fall slowly. The longer we wait, the longer it will take (I presume that is your get worse statement). You have not given me any reason to think that this is not reversible.Response:[DB] If we cease all human CO2 emissions all hold them at zero ad infinitum, then CO2 levels would first begin to flatten their rise and then plateau on the decadal level. The natural sinks would begin their slow draw-down on the centannial& millennial timescales. All the while the system will be changing to reach a new thermal equilibria & temps will continue to rise...and ice will continue to melt. For centuries and millennia (repeat as needed). The loss of the WAIS and the GIS, which is in store before equilibria can be reached, is not reversible except on the hundreds-of-millennia to millions-of-years timescales. Unless you're a Timelord like Dr. Who...
You really are not doing well in retaining credibility here with your unscientific opinions. Perhaps a change in venue is needed, where said opinions will be more welcome & reflective of the caliber of the Forum in which they're posted?
Eric the Red at 09:31 AM on 24 June 2011How would a Solar Grand Minimum affect global warming?
Actually meant to say rebutal. Most scientific progress builds on previous work.Eric the Red at 09:29 AM on 24 June 2011The Last Interglacial - An Analogue for the Future?
If you like, you could average the last 11 years. That would be close enough to today.michael sweet at 09:10 AM on 24 June 2011Websites for Watching the Arctic Sea Ice Melt
If we stopped emitting CO2 today the temperature would continue to increase for decades because of the heating in the pipeline. It is prohibitively expensive to remove the CO2 and pump it under ground. The temperature effects already measured are enough to raise sea level several meters . This will flood Florida and Bangladesh, in addition to many huge cities. In the past year China, Russia, Australia, the USA and the Amazon have had record damaging weather. How will these effects be reversed, since it will not get cooler? You have presented only your unsupported opinion so far. How will the effects of the permanent pollution that has been put in the atmosphere be reversed??? Provide data and references to support your extraordinary claim. Comments made without evidence can be dismissed without evidence. I dismiss your claim without evidence. We need to take immediate action to keep things from getting worse. The longer we wait the worse it will become. The uninformed opinion that things will reverse in the future, for no apparent reason, does not help motivate people to take action.skywatcher at 08:55 AM on 24 June 2011Sea Level Hockey Stick
#65 Sphaerica, maybe some of your distant relatives, the deep sea benthic Gromia sphaerica have been getting much fatter in recent years and displacing more water. Can't rule it out, right? We'd best do some serious sphaerica harvesting before sea levels flood the major cities. :) I'll get me coat...
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