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John Hartz at 01:13 AM on 27 June 2011Sea Level Hockey Stick
"Sea Level Study Leads to Divisions" is an in-depth review of the Kemp et al paper posted on Spiegel Online International. A number of prominent scientists, including Mojib Latif, were interviewed and are quoted. -
John Hartz at 00:59 AM on 27 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
The International Climate Denial Spin Machine has now set-up shop in India... New Delhi/Bangalore, June 18: Several environmental groups, including Climate Revolution, have criticised the Delhi-based Liberty Institute, the Institution of Engineers, Karnataka state Centre (IEI-KSC) and the Karnataka Environment Research Foundation (KERF) for claiming that passive smoking isn't harmful. They have also questioned as to why these three institutions are now being employed by oil companies to question climate change. Source: "Climate change deniers spreading misinformation: Environmental groups", DailyIndia.com, June 18, 2011 -
Norman at 00:50 AM on 27 June 2011Linking Extreme Weather and Global Warming
Rob Painting @ 229 I have read this Jeff Masters post and am currently looking into it. He does use choice words however to give a boost to his conclusions. Here is an example: " The atmospheric circulation in the Arctic took on its most extreme configuration in 145 years of record keeping during the winter of 2009 - 2010. The Arctic is normally dominated by low pressure in winter, and a "Polar Vortex" of counter-clockwise circulating winds develops surrounding the North Pole. However, during the winter of 2009 - 2010, high pressure replaced low pressure over the Arctic, and the Polar Vortex weakened and even reversed at times, with a clockwise flow of air replacing the usual counter-clockwise flow of air. This unusual flow pattern allowed cold air to spill southwards and be replaced by warm air moving poleward." Extreme configuration and unusal event? Looks like The AO is highly variable and that looking at a historical graph does not look so "extreme". Yes a record breaker but not highly unusual. Graph of the AO. -
John Hartz at 00:41 AM on 27 June 2011Uncertainty in Global Warming Science
@Sphaerica#4: Your statement, "Everyone knows the system is chaotic, and includes substantial noise as well as impediments to direct measurement." may not be understandable to the average person reading this comment thread. Please elaborate. -
Bob Lacatena at 00:40 AM on 27 June 2011Sea Level Hockey Stick
114, okatiniko, The references that I've found point to substantially more problems that you seem willing to recognize. The words "deeply flawed" are directly attributed to their paper, and in particular, the Lasso method they used appears to be unjustified and rather subjective. Their selection of data points was invalid, and proper selection yielded markedly different results. In fact, when applied properly, their own methods in comparison to MM08 yielded "considerably higher probabilities up to 99% that recent decadal warmth is unprecedented for at least the past millennium." [Gavin Schmidt and Michael Mann, two people who are competent -- I'd argue that Gavin is probably one of the most intelligent, well-educated, well-trained and skillful people I've encountered in my none-too-sheltered life.] From RealClimate:In this sense, the MW analysis, using the proper proxy data and proper methodological choices, yields inferences regarding the unusual nature of recent warmth that are even more confident than expressed in past work.
I would not say the book is closed on this, but this is substantially beyond your assessment of "a controversy about their conclusions," and given the great number of specific, negative points made by a variety of investigators about their methods and conclusions, I myself find no merit in holding up their work as a point in any debate. Indeed, this entire hockey stick controversy is rather ridiculous, and I believe it serves the "denial cause" poorly to keep trying to stand by it. Every graph I look at, from temperatures to ice melt to sea level rise to anything else, all without any sort of PCA, centered or otherwise, shows some sort of hockey stick. Honestly, at this point the "Hockey Team" is not some cabal of evil scientists, but rather every temperature related measurement that one can think of. There are enough hockey sticks not merely to field a hockey team, but also to provide the second and third lines needed to win a Stanley Cup (Go Bruins!). To argue about hockey sticks is to close one's eyes to the obvious evidence that the earth is warming at a dramatic and unheard of pace. Losing oneself in centered-PCA, he-said/she-said arguments is just one more way of ignoring the unpleasant facts. -
Eric (skeptic) at 00:34 AM on 27 June 2011CO2 has a short residence time
Dikran, when you say "So it is very unlikely that the surface oceans were mopping up half of the excess forming the seasonal cycle, unless it were giving it back again in the oposite phase of the cycle." I assume you mean preindustrial? Then I am in violent agreement. Why would it be any different from today, except for the year over year increase from fossil fuels? The total fluxes are much larger than the net fluxes from seasonal vegetation (I routinely read 100 Pg of C). However, where I think we differ, is that there is no evidence that the oceans are mopping up any more than a very small portion (a few percent) of the seasonal excess. I noticed the weather noise in the papers and that does argue the opposite of my conclusion, that the top layer ocean is very actively sequestering and releasing CO2 essentially based on ENSO. The problem is that worldwide averages such as average SSTs are quite useless in this situation since the sequestration and release of CO2 from that top layer is very nonlinear. So like you say, we can't do it without a model and that model has to be girdded with some detail. -
Norman at 00:32 AM on 27 June 2011Linking Extreme Weather and Global Warming
Too cold to snow? Fairbanks, Alaska is located in the interior of Alaska. Here is the average climate for this location. You can see the average monthly temps (in F or C) and you can look down at the average snowfall. Fairbanks is a very cold place in winter yet seems to receive a lot of snow (69" annually) Fairbanks Alaska climate data. -
Bob Lacatena at 00:22 AM on 27 June 2011Uncertainty in Global Warming Science
1, Ken, My apologies. In re-reading things, you were obviously trying to (humorously) emphasize exactly the point that Dr. Franzen was trying to make with a rather subtle Poe (so subtle, that I missed it). Well done. Thank you. Just to answer your question, however, the 0.85 W/m2 figure from Hansen 2005 was derived from GISS climate model runs from 1880 to 2003, while the 0.59 W/m2 figure from Hansen et al 2011 was for the period from 2005 to 2011. Hansen et al 2011 also contains an estimate of 0.80 W/m2 for the period from 1993-2008, and 0.70 W/m2 for 2003-2008. Error bars are included with all estimates, and all use a variety of papers and techniques as sources for the computations. Different techniques, over different time periods, would of course yield different results. Everyone knows the system is chaotic, and includes substantial noise as well as impediments to direct measurement. As I've already said, this is in fact a main point of Dr. Franzen's post, and that you have highlighted this with your question (one a little more nuanced than a simple "hockey-stick" reference) does in fact help to clarify his main point, which is that once one accepts the science, then arguing about the measured details is worthwhile and necessary. But the answer to your question is easily determined simply by looking at the actual content of the two papers you sited. From Hansen 2005, Table 1:Effective climate forcings (W/m2) used to drive the 1880 to 2003 simulated climate change in the GISS climate model
From Hansen et al 2011:Our estimated planetary energy imbalance is 0.80 ± 0.20 W/m2 for 1993-2008 and 0.59 ± 0.15 W/m2 for 2005-2010, with estimated 1-σ standard error. Our estimate for 1993-2008 uses the Lyman et al. (2010) ocean heat gain rather than Levitus et al. (2009) for the reason discussed in section 10. The estimated error in 2005-2010 is almost as large as that in 1993-2008 because of the brevity of the period. Sampling error in the Argo era will decline as the Argo record lengthens (von Schuckmann and Le Traon, 2011), but systematic biases may remain.
There is much more in both papers. I'm sure that if you read them in their entirety, you'll find the answers to any questions you may have. -
Eric (skeptic) at 00:21 AM on 27 June 2011Uncertainty in Global Warming Science
Type A = AGW. Type C = CAGW. -
Bob Lacatena at 23:47 PM on 26 June 2011Uncertainty in Global Warming Science
1, Ken, If you have a point, make it. Posting nothing but questions just demonstrates a continued need to sew doubt without even attempting to look for or wanting to find the answers. -
Ken Lambert at 23:28 PM on 26 June 2011Uncertainty in Global Warming Science
"On the other hand if they accept the basic science but deny the hockey stick then it can be worthwhile exploring their concerns and pointing out that the hockey stick result follows straightforwardly, if not rigorously, from the known increasing energy input into the earth." Quite right. So what is the value of the "known increasing energy input into the Earth".? It it 0.9W/sq.m from Hansen 2005 or 0.59W/sq.m from Hansen 2011? -
Dikran Marsupial at 21:18 PM on 26 June 2011CO2 has a short residence time
Eric@98 I do not think the conclusion in the third paragraph of your post is supportable. Just because the oceans do not rapidly take up half of the seasonal variation (which is mainly due to changes in the terrestrial biosphere) does not mean that the ocean is not absorbing half of anthropogenic emissions on an annual to decadal scale. The pre-industrial approximate equilibrium means that fluxes between the terrestrial biosphere and oceans must be in approximate balance (otherwise one or the other would be depleted). So it is very unlikely that the surface oceans were mopping up half of the excess forming the seasonal cycle, unless it were giving it back again in the oposite phase of the cycle. If you look at the annual ratio of the increase in atmospheric CO2 to anthropogenic emissions for that year, you will find it is very noisy and only averages out to about 45% over the course of a number of years. Weather noise is so great that you can't get a reasonable estimate of where the carbon goes on a year-to-year time-scale, without the use of physical models. -
Rob Painting at 21:00 PM on 26 June 2011Breathing contributes to CO2 buildup
J87 - No. We are referring to 'natural' carbon cycling. Fossil fuels were removed from the surface carbon reservoirs a long time ago, and played no part in the carbon cycle. Humans then came along, extracted, refined and burnt those fossil fuels, releasing all that 'additional' carbon back into the atmosphere. Hence we have a problem of humungous proportions. -
Robert Murphy at 20:54 PM on 26 June 2011Breathing contributes to CO2 buildup
j87, #13 "For example, CO2 emmissions from burning coal or oil are also part of this cycle." That carbon had been locked out of the carbon cycle for hundreds of millions of years. What we are doing is reintroducing it to the carbon cycle, at a very great speed, far faster than natural carbon sinks can absorb it. Therefore, atmospheric CO2 is steadily rising. "The plants that absorb the CO2 grow, die, fall to the ground, are pressurised for millions of years and then turn into Coal or Oil." Almost all of the plants that die now decay and ultimately release CO2 back into the cycle. They do not become coal or oil. -
les at 20:35 PM on 26 June 2011Sea Level Hockey Stick
12 - "I am not competent enough to say who is right" That is clear given your posts here and on other blogs. However it is clear to those who are that the random inputs do not give rise to hockysticks without assistance. ", and you aren't probably either." I'll thank you to make no such presumption! I've worked with a good veriety of models and data which include noise of various flavours and gave never generated any structure - let alone a hockystick - from the noise. Your remarks sum to no more that "there are uncertainties so maybe I'm right and I'm not prepared to listen to anyone's opinion. " Unless you can provede analysis to substantiate your claim, independently of the corrupted material to which we have both referred you should withdraw your accusation. You can not fall back on "well you and I don't understand it" to support your argument... ... that kind of argument should be left to the leprechauns. -
j87 at 20:16 PM on 26 June 2011Breathing contributes to CO2 buildup
This article doesn't quite hit the nail on the head. For example, CO2 emmissions from burning coal or oil are also part of this cycle.. The plants that absorb the CO2 grow, die, fall to the ground, are pressurised for millions of years and then turn into Coal or Oil. So isn't burning fossil fuels just an extension of this carbon cycle? -
Michele at 20:00 PM on 26 June 2011The Planetary Greenhouse Engine Revisited
@ Patrick Venus and Earth have the same behavior at the bottom of the thermosphere where starts a large cooling layer which, thermally, can solely radiate to space. Of course, this is due to the fact that the molecular CO2 appears just at that altitude, not above because the EUV, and it is the easiest vibrationally excitable molecule by means of the thermal molecular collisions. The temperature shifts leftward simply because the CO2 is able to heat-radiate. At the equilibrium the sum of the thermospheric downward flux (by diffusion) and the mesospheric/tropospheric upward flux (by convection) must balance the outgoing radiative flux. Why the altitudes and the temperatures of the two planets are about equal? I don’t know. For Venus the underlying convective layer starts from the surface and thus an air particle (which reaches the radiating layer as a sounding balloon), has to fill up its enthalpic tank at least with an amount equivalent to the geo-potential energy that it must acquire to carry aloft whatever little thermal pay load that will be elaborate within the radiating layer. That’s, the particle, at least, needs a temperature T0 = T + gH/Cp, where T is the temperature at the altitude H of the radiating layer. This means that Earth and Venus would have temperatures about equal at the surface, if Earth had also a sole convective layer below the radiative one. Fortunately Earth’s atmosphere contains oxygen that absorbs the UV creating an heating middle layer (stratopause) which breaks the convection and produces the constitution of the stratosphere that transfers downwards part of the absorbed heat. The temperature shifts again leftward simply because the strato pause and the surface aren’t able yield the heat that the CO2 heat-radiates between them. At the equilibrium the sum of the stratospheric downward flux (by diffusion) and the tropospheric upward flux (by convection) must balance the outgoing radiative flux. That’s, the lower atmosphere repeats the same behavior of the higher one. The convective layer starting at the surface with a negative lapse rate (troposphere) and the stratosphere produce the constitution of the middle cooling layer (tropopause) where the CO2 once again radiates . In this way the oxygen avoid to Earth a lethal overheating of about 450°C. -
Rob Painting at 19:28 PM on 26 June 2011Linking Extreme Weather and Global Warming
Norman - "I have a question about what appears to be a drastic rise in flooding events. Could this be explained as greater awareness because of better global media coverage? Not saying it is the case but is this a possibiltiy? Not likely, considering the vast scale of the flood events. Jeff Masters has summed up the last year or so in his post 2010 - 2011: Earth's most extreme weather since 1816? -
Norman at 19:10 PM on 26 June 2011Linking Extreme Weather and Global Warming
I have a question about what appears to be a drastic rise in flooding events. Could this be explained as greater awareness because of better global media coverage? Not saying it is the case but is this a possibiltiy? As reference. The News media has extensive coverage of most flooding these days. It makes it appear flooding events are much more likely and worse today. Increasing in frequency. Here is a record of Mississipi floods. Flooding events do not seem that unusual for this large river. Mississipi river flood events. Maybe it is caused by selective perception. We hear about a river flooding and a communities that are devestated (like Minot, North Dakota or Hamburg, Iowa) so it appears that such disasters are greatly increasing in number and severity. Could if be a minuse of information gathering? Like in the case of identical twins that are separated while young. Psychologists showed amazing similarities in likes and dislikes even though they were raised in different environments. Is this selective perception. You have an extremely large sample size to choose from and if you only select some matches from a huge set of possibilites you can make it appear an amazing link. Likewise with flooding. People here make the link that Global warming is causing many more floods with greater intensity flooding. But here is where the selective perception may come in. Every year a few rivers will flood and be reported upon. What of all the numerous rivers that did not flood in that year? Examples... Rivers in Nebraska that could flood and cause a disaster. Note the large number of rivers in just this one state, each with the potential to devestate some community that might lie near one of them. Look at the number of major rivers in Europe. There are several more minor rivers anyone of which could cause a disaster if a very heavy localized rain would occur in that river's basin. List of major rivers in Europe, note even this is a good number. A better study than media reporting to influence our perception would be to create a large data pool of rivers (maybe a few thousand global rivers). Monitor yearly flooding for a period of time and note if there seems to be a steady and consistent increase in flooding events and their severity. -
Norman at 18:44 PM on 26 June 2011Linking Extreme Weather and Global Warming
The next thing to study is to plot all the winter snowfall accumulations for Omaha Nebraska vs Global warming to see if there is a correlation between higher snowfall and Global warming as some have speculated should occur. I am not sure how the connection is made that a 4% increase in Global humidity (still want to know how someone determines this as Global humidity is very far from constant, evaporation rates are not constant nor is rainfall) will result in much heavier snows or rainfall amounts that lead to much greater flooding. I do not see how the math adds up. A 4% increase in Omaha's snowfall accumulation would average out at an inch more of snow per season. Something hard to see in a record that can very by several inches from one year to the next. -
Norman at 18:38 PM on 26 June 2011Linking Extreme Weather and Global Warming
To anyone interested, There have been several posts on the topic that warmer weather will increase snowfall amounts. I am doing a limited test of this conclusion to determine if it is a valid conclusion based upon availabel evidence. I am picking one location (Omaha, Nebraska) as the test spot. Based upon the theory it should not matter where the test spot is located as this principle should apply to all regions. The concept is that warmer temperatures will lead to greater winter snowfall because warm air can hold more moisture. My understanding of weather systems is of a different nature. It could be caused by Global Warming but at this time I have not been able to make such a connection. I have learned that heavy snow or rain (at least for the plains of the USA) are caused by very strong low pressure systems that move across the Nation from West to East motion. In the US, a low pressure spins counter-clockwise. On the east side the air will pull warm moist air from the Gulf of Mexico (still warm water even in winter) and at the same time pull frigid Canadian air down from the north on the west side of the pressure system. The stronger the low pressure system, the more moist air it will pull up and the colder air it will pull down. This action causes rain and snow as the cold air moves under the warm moist air lifting it to condensation levels...the heat of condensation causes further lifting of the air pulling in even more moist gulf air. Heavy rain and snow are the combination of two events. The stronger the low pressure the greater is the intensity of the rain or snow. But intensity alone are not the only variable in determination of heavy rain or snow. The speed at which a low moves across the country is very important. Case of point. In Omaha Nebraska on Saturday morning there was a heavy rain of over 2". The local meterologist described the cause of the heavy rain as the product of the storm system stalling over an area before moving again, dumping a large amount of rain in a particular area. Back to the snowfall research. Omaha, NE snowfall in 2009-2010 winter season was 47.6". Normal snow amounts for an Omaha winter are 27.1". That winter season had 20" above normal snowfall (is that an extreme event...it did cause many accidents and cost a lot of money to the city for plowing). Source for Omaha snow accumulations used for this study. Going to the GISS temp anomaly map for this winter period, this season was shown to be below normal for Omaha which received well above normal snowfall amounts. Note to Tom Curtis. I do realize this is a very limited research test and may not satisfy all scientific rigor. I am doing it primarily to test the idea which so many believe is a rigid truth. GISS temp anomaly for winter of 2009-2010. (If anyone is interested in this project, Omaha Nebraska is located around the center of the United Sates) Snow for the 2003-2004 winter season had 47.8 inches and the temp anomaly for Omaha was above normal. GISS temp anomaly for winter 2003-2004 Now to try a low snowfall amount much below normal. The winter of 1980-1981 was 9.1" of snow accumulation, much below normal. Temp anomaly for this year was above average. GISS temp anomaly for winter 1980-1981. The two heaviest snowfall accumulations on the NOAA data page. 1961-1962 51.6" of snow accumulation neutral temp anomaly 1959-1960 56.7" of snow accumulation little colder than normal but not much. GISS temp anomaly for winter 1961-1962. GISS temp anomaly for winter 1959-1960. -
Steve Brown at 18:10 PM on 26 June 2011The Last Interglacial - An Analogue for the Future?
The basis for my saying that the climatic changes during the Eemian happened over a few 1000 years was in regards to the orbital and GHG forcing that led to the warming out of the penultimate glaciation through to the Eemian climatic optimum. WRT the various Hearty et al. papers that Sentient mentions, the authors themselves acknowledge that the evidence for a rapid highstand may also be explained by tsunami or severe hurricane storm surge activity that just affected the Bahamas. I'll be covering this in a future post in the series. -
Marcus at 17:57 PM on 26 June 2011A Detailed Look at Renewable Baseload Energy
@ okatiniko. I also have to point out that you appear ignorant as to what stable energy supply means. Its not a factor of what percentage of the total is provided by renewable energy-its whether the renewable energy component is capable of providing their energy to the grid almost 24/7-without the need for a back-up. In this regard, several Countries already have stable renewable energy in place, & several other Countries are moving to have this in place too. Of course even Coal & Nuclear aren't always available 24/7, & nor can their output be properly adjusted to fit with demand-which is the complete opposite of most renewable energy systems. Also, as I've pointed out above, what happens if the coal or nuclear power station breaks down for some reason? What if part of the T&D system fails? You could be blacking out an entire Town or City, whereas the loss of a single wind turbine or solar panel isn't going to be as disastrous. The fact is that in spite of your desperate attempts to disparage renewable energy, they're going to be a much better fit within a more efficient & distributed energy grid than Coal or Nuclear will ever be! -
Marcus at 17:51 PM on 26 June 2011A Detailed Look at Renewable Baseload Energy
"Since nations having a lot of hydro potential have achieved a 100% or almost 100 % renewable power for years, there is obviously inordinate difficulty in doing that without it" Wow, more dodgy logic from the "We Hate Renewable Energy Crowd". The only reason it worked so easily for hydro-power is because Hydro-power provides its own storage, & always has done. Be warned though that even Hydro can run into problems if you have an extended drought. Of course Hydroelectricity has started moving into an age where the need for large storage capacity dams will become a thing of the past. Run-of-the-river & other Small Scale Hydro project means any nation with at least one river could provide renewable energy from Hydro without the need for large Dams. Geothermal power & bio-electricity also provide base-load capacity, & always have done-its now just a matter of expanding the size of these 2 sectors where they're available. As for other forms of renewable energy, they've really only been around since the mid to late 1980's, & base-load storage for them has only become available in the last 10-15 years. So its no surprise that most of them still lack base-load capacity. As I said above though, with various nations expanding their renewable sector beyond peaking capacity, they are increasingly starting to move towards the inclusion of base-load storage in most renewable energy systems. The fact that some Countries are starting to make the move *proves* that its feasible to do so. -
okatiniko at 17:07 PM on 26 June 2011Sea Level Hockey Stick
There was a controversy about their conclusions (that real proxies didn't have a better skill to reproduce the temperature than random pseudo-proxies), but not on the very fact I mentioned, that you get a hockey stick shape even with random proxies. The exact amount of error introduced by the use of proxies is obviously a very technical point disputed even among specialists. I don't think anybody here (including me) is really competent to say who is right. But to my knowledge, nobody denies that proxies generally introduce a loss of variance in the past. -
okatiniko at 16:37 PM on 26 June 2011A Detailed Look at Renewable Baseload Energy
Tom#59 since nations having a lot of hydro potential have achieved a 100% or almost 100 % renewable power for years, there is obviously inordinate difficulty in doing that without it, or you can't explain why those deprived of enough hydro power haven't. I know of course that geothermal is stable, also it is not the only criterium : the power generation must be able to react quickly to peak demand, which implies the possibility of extra power generation at moderate cost. Hydro (or thermal fuel) storage makes it possible to adjust the instantaneous power without loss of total integrated production, which is not the case for intermittent energy or geothermal. So you can admit a part of renewables (except hydro), but nobody has ever succeeded in doing that entirely, and again, even countries with a lot of renewable power have still a high carbon intensity. The amount of renewable energy, w/o hydro, has increased in 2010 from 137 Mtoe to 159 Mtoe (source BP statistitical review). That's a lot, but it represents only an increase of 0,1 % of the total share of energy (1,2 to 1,3 %). Obviously if you want to reach 100 % before the total exhaustion of fossil fuels, you need a serious acceleration by at least a factor ten or more. I will start to believe in computer simulation when the increase will reach more than a few % a year . -
Rob Painting at 16:00 PM on 26 June 2011The Last Interglacial - An Analogue for the Future?
Sentient - "I am not so sure that "The climatic changes during the Eemian happened over several thousand years and not in a few decades" Maybe not the right choice of words perhaps, but I think Steve was referring to the astronomical forcing. The rapid jumps in sea level near the end of the Eemian are likely from the collapse of the Greenland Ice Sheet - not a good omen. Somes_J - as already pointed out, there are different factors in play today, the slight change in ocean circulation between the Pliocene and today (such as restriction of the Indonesian Throughflow) can have a marked effect on regional and global climate. For example this study: A westward extension of the warm pool leads to a westward extension of the Walker circulation, drying eastern Africa - Williams 2011 anticipates warming of the Indian Ocean will dry out East Africa. Check out the SkS post The Dai After Tomorrow, the global drying trend has already begun, and this at a time of globally increasing rainfall! -
Miriam O'Brien (Sou) at 15:25 PM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
If you read some of Carter's pieces in Quadrant, you'll find him in a single article saying all of the following: It's warming, it's not warming, it's cooling. He doesn't even know what's happening at all. In a video presentation he said he was 'agnostic' which means he doesn't know if it's warming or cooling and he thinks it cannot ever be known. Carter is a very mixed up man and doesn't know his own mind on the matter. Makes one wonder why he ventures to offer any opinion let alone try to write a book on the subject. -
Eric (skeptic) at 15:10 PM on 26 June 2011CO2 has a short residence time
Thanks Tom for explaining the rapid equilibrium with the upper ocean layer. If we posed the hypothetical question, what if mankind doubled or halved his contribution from one year to the next, would the upper layer of the ocean still absorb roughly 50%? Fortunately we can answer that question since nature performs this experiment every year. In the NH fall, the biosphere injects about 7 Pg net C into the atmosphere from (I added the NH amounts in table 3 in Randerson et al.: Trends in Seasonal Cycle of Atmospheric CO2 in Global Biogeochemical Cycles, vol. 11, no. 4, pages 535-560, December 1997). These estimates come from measurements of CO2 released and absorbed by various forest types times their area so are mainly empirical data. The comparable empirical data are the 750 Pg C in the atmosphere, the 390 ppm total and the 7 ppm annual cycle (peak to peak or 3.5 trough to peak). That works out to 6.75 Pg of fluctuation versus 7 Pg from the biosphere (net). There are some caveats, the oceans in the SH have a somewhat complementary cycle when they warm in the NH winter and consequently absorb less CO2 a bit after the the NH biosphere is releasing its annually stored CO2. Irregardless, it is clear that comparing the 6.75 to the 7 means that the top layer ocean in general (although mostly NH) absorbs very little of the CO2 released by the biosphere annually. That means that top layer ocean also does not absorb 50% of man's annual output or anything close to that. A much better numerical match is the 2% of man's total excess as I stated above. Another caveat is that the CO2 annual release doesn't mix worldwide in the atmosphere that quickly, but neither does the fossil CO2 in your scenario (it is also mostly NH). Briefly looking at Archer 2008, he and I agree when he states "Of the 9 Gton C/year carbon release from fossil fuels and deforestation from the year 2000 to 2006, 5 Gton C/year is taken up naturally, half by the ocean and half into the terrestrial biosphere (Canadell et al. 2007). One might conclude from these numbers that the uptake time for CO2 must be only a few years, but this would be a misconception. The rate of natural CO2 uptake in any given year is not determined by the CO2 emissions in that particular year, but rather by the excess of CO2 in the atmosphere that has accumulated over the past century. " Other than that, we aren't talking about the same processes since I am referring to the response of the top layer ocean with reasonable turnover to the deep ocean (I have explained on other threads why the deep ocean turnover is so high, it is the reason that the observed warming lags the theoretical warming). His paper discusses an active ocean and other active GHG production made active by AGW. My spreadsheet assumes (and matches the reality to the current day) that the system is passive. -
Riduna at 14:30 PM on 26 June 2011The Last Interglacial - An Analogue for the Future?
Hansen et al 2011 warns that we are now a few tenths of a degree below the Eemian and that allowing average global temperature to rise to +2°C above pre industrial will put us over the Eemian maximum. Were that to occur we expose ourselves to decadal doubling of Greenland ice loss, rapid increase in loss of WAIS ice loss, reduction of global albedo and excursion of Arctic carbon, making a 5m rise in sea level by 2100 certain. Hence the call to limit future carbon emissions to 350 ppm by 2050 in order to avoid these outcomes. We are now approaching 400 ppm. Since major CO2 emitters are pursuing BAU, the chances of average global temperatures rising by 4°C or more by 2100 seems pretty good, 3°-4°C above the Eemian maximum and we know what we can expect from that. Moreover, contrary to the views of some, homo sapiens is knowingly achieving this with very little help from other factors and, contrary to the assertions of some, none from the Milankovitch Cycle. The sun is not only quiescent but Earths orbit around it is almost circular and the axial tilt of the earth is gaining such that polar exposure to the sun is decreasing. The world during the Eemian may have had similarities to what it is to-day but it also had significant differences. For example, it was not inhabited by voracious animals, homo sapiens, which have bred to plague proportions. It did not have 7 billion human inhabitants, 4 billion of them living in areas subject to inundation by a 5m sea level rise, 2 billion dependent for water on glaciers most of which will be fully melted by 2100, or 1 billion dependent on marine animals which will be scarce or extinct by then. One would have thought such outcomes would have prompted Australian Prime Minister Gillard to abandon her tokenistic goal of reducing CO2 emissions by 5% by 2020 when all around her are aiming for 25% reduction by 2020, even zero by 2050. Think, Mr Abbott, what these developments are going to do for the economy, competitive advantage and the job protection you bleat about. There are times when pollies – and academics – make you sick! All talk, too little action and total disregard for the consequences. -
Camburn at 14:19 PM on 26 June 2011The Last Interglacial - An Analogue for the Future?
sentient: Hope your vacation is productive. As always, you provide well documented thoughts in this area. -
Marcus at 13:22 PM on 26 June 2011A Detailed Look at Renewable Baseload Energy
@ okatiniko. At present, most renewable energy around the world is set up strictly with *peak* power production in mind-which is fine when it only makes up 5%-15% of total demand. However, as the proportion of electricity obtained from renewable sources continues to grow, you'll see a switch towards stable base-load capable versions of existing forms of renewable energy. Of course you continue to refuse to even admit that the Geothermal Power of Iceland, Hawaii & New Zealand all meet the criteria of *stable* base-load power...i.e. that it is power that doesn't vary in output regardless of the time of day or night. Germany & the State of Texas are already making moves towards making their renewable energy sources more stable-with Germany switching to pumped storage & Texas switching to Compressed Air. So you see that Governments are already waking up to the Fossil Fuel Industry lie that renewable energy can't generate stable, base-load power. -
Marcus at 13:13 PM on 26 June 2011A Detailed Look at Renewable Baseload Energy
MattJ, as Dana rightly points out, there is a massive difference between CO2 that is part of the natural Carbon Cycle, & the CO2 that was part of a Carbon Cycle from millions of years ago. If a power station is converting more harmful methane to CO2, then its doing us a favor-especially if we also make the effort to capture & re-use some of the CO2 produced as either fuel or electricity. Additionally, if it prevents the combustion of fossil fuels, then this is also a good thing. Obviously I'd rather we rely more on truly zero emission technologies, but I still thing bio-electricity has a place in future energy grids. -
Rob Honeycutt at 10:46 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
heystoopid... I actually find a few published papers on paleoclimate that Carter has published. At very best he has a very thin resume of actual work in this field which he comments so profusely and inaccurately on. -
sentient at 10:27 AM on 26 June 2011The Last Interglacial - An Analogue for the Future?
Unfortunately, I must exit further discussion at this time. Preempted by vacation. Laptop is next on the final packing list, and where I am going the only connection is with nature. I will check back on 5Jul11. Be good. -
heystoopid at 10:21 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
Ouch! Reading Bob Carter's anti-science propaganda drivel, hurt my brain. Amazon's internal book review hyperbole "Professor Robert Carter - Professor Robert Carter is one of the world's leading palaeoclimatologists, and his work investigates the past cycles of the earth's unpredictable natural climate change, especially over the last few million years of planetary ice ages." Desmogblog: Bob Carter:http://www.desmogblog.com/rm-bob-carter Perhaps, those who have managed to read this anti-science book, could dispel the myths of how a geologist, who has published zero peer reviewed research papers on palaeoclimatology, became an overnight expert in that subject. -
pharmacy tech at 10:09 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
The carter reality ignored the evidence presented to confirm global warming. Some agree with him but personally I don't Robert -
Tom Curtis at 09:35 AM on 26 June 2011A Detailed Look at Renewable Baseload Energy
okatiniko, I have noticed that no nation without large scale hydro or geothermal power has yet tried to convert to 100% renewable electricity generation. Therefore the notion that there is some inordinate difficulty in doing so is entirely theoretical, and is not based on empirical observations, at least as you judge these things. Therefore, logically your entire opinion on this subject is that you have no opinion one way or the other. One wonders then why you keep flapping your jaws. If perhaps, you have noted that wind power is intermittent and that solar power is intermittent, and concluded there may be some difficulty, that is very interesting, but invokes a different standard of evidence to that which you invoke to maintain your supposedly agnostic position. Allowing the same standard of evidence, we can then note that there are currently operational solar power plants that can operate in hours of darkness by means of thermal storage of energy. Examining the details of current technology, therefore, shows no impediment to 100% renewable electricity. This point has now been raised several times by several people, and you have just ignored it, and restated your original, and irrelevant objection. That sort of response is called "trolling". -
Bob Lacatena at 08:46 AM on 26 June 2011Sea Level Hockey Stick
okatiniko, Have you done any appropriately skeptical research to see if McShane and Wyner has any flaws as a paper? -
nealjking at 08:07 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
"It has also ignored the evidence that carbon dioxide concentrations in the atmosphere are higher than the concentrations in the upper layers of the ocean, so there is a net flow of carbon dioxide from the atmosphere into the ocean." This statement needs a little clarification: How do you compare a concentration of CO2 in the atmosphere (a gaseous phase) with that in the ocean (a liquid phase)? There's a correspondence between the partial pressure and the concentration (Henry's law) in equilibrium; but I think a slightly more careful statement is needed. -
arch stanton at 07:32 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
The parallel ant-science universe; universe modoki. I agree with Don’s comment (#1). -
Philippe Chantreau at 07:14 AM on 26 June 2011The Last Interglacial - An Analogue for the Future?
Somes_J, I'm not sure that this comparison is so useful, now that the Isthmus of Panama is closed. A lot of things have changed since the mid-Pliocene. It is an interesting exercise in modeling, but probably not as good an indication for our future as what model results with current conditions and geography yield. -
okatiniko at 07:04 AM on 26 June 2011A Detailed Look at Renewable Baseload Energy
"@ okatiniko, you asked which countries had *stable* sources of renewable energy-namely sources capable of producing 24/7 power-" I asked which countries had stable power without hydro or fossil fuel , and Iceland definitely doesn't fits the description since it has also a lot of hydro power. Now don't ask me to prove it is impossible, because I never claimed that. I just said it is still to be proved. Man has walked to the moon, but didn't go to other stars, although many people think it could. This is also yet to be proved. You're inverting the burden of the proof. "The point is that any lack of 100% Renewable Energy has much more to do with a lack of political will than a lack of technical feasibility" And so magically this lack of political will didn't prevent countries like Norway and Iceland to have 100 % renewable energy ? how do you explain that policymakers love water, but not air and sun ? -
Somes_J at 06:57 AM on 26 June 2011The Last Interglacial - An Analogue for the Future?
Eric the Red: "Here is were the theories diverge. Some state that an expansion of the ITCZ will simply push the desert regions poleward, causing the semi-arid regions to dry into deserts. Others maintain that the deserts will shrink in size as the ITCZ expands, but the poleward side of the desert remain where htey are today." It seems to me that this question might be testable by looking at whether deserts moved north in previous warm eras. It occurs to me that perhaps a better model for a global warming world would be the Mid-Pliocene rather than the Eemian, as the greater warmth of the Mid-Pliocene may have been due to higher than present CO2: LINK I have managed to find a paper that has a reconstruction of Middle Pliocene ecosystems: http://pubs.usgs.gov/of/1999/of99-535/ From their summary: "Expansion of evergreen forests to the margins of the Arctic Ocean, a reduction of desert area in equatorial Africa and essential elimination of polar desert and tundra regions in the Northern Hemisphere. A small amount of deciduous vegetation occurred at the edge of the Antarctic continent." They include vegetation maps. There's still a large barren area in Africa but it's smaller than today. Barren areas generally seem to be smaller than today. If the Mid-Pliocene warmth was because of higher CO2 it seems that CO2-caused warming also leads to less desert, not more. Any difference between the Mid-Pliocene and today that might explain why deserts would have been smaller than, but you'd have increasing tropical aridity from warming today?
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Philippe Chantreau at 06:35 AM on 26 June 2011The Last Interglacial - An Analogue for the Future?
I find a lot of speculation in Sentient post, about a subject that is itself much speculated about. D.O. events, Heinrich events and the more recent Bond events (of which only a few can be conclusively linked to large scale climate fluctuations) are most likely the results of oceanic currents modifications due to disruptions by fresh water. There has not been a D.O. event in over 20k years, yet no ice age has started, even though we've been at only 285 ppm for all of that time. The bipolar ocean seesaw indicates that these "cycles" (true cyclicity is questionable) are mostly about redistributing heat. If Bond events truly are cyclic, then the present warming does not correspond at all to a Bond event. I'd add that nobody is advocating reducing CO2 concentration but rather preventing it from increasing in a way that has no known geologic equivalent during mankind's presence. A "natural" outgassing like we're seeing now, if coming from volcanoes, would require a volcanic activity about 150 times more intense than what it presently is. Whatever else is "naturally happening" according to Sentient is bound to be profoundly affected. This link has lots of good info and references. -
villabolo at 06:24 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
"In the Carter reality, the increase in global temperatures due to a doubling of carbon dioxide is low, only about one degree. This is a strange thing to mention as, in that world, there is supposed to be no warming . . ." That reminds of Lord Monckton's "reality". He claims that a doubling of CO2 (400-800 ppm) will give us as little as 1F maybe .5. That's due to CO2 having 1/6 the insulating effect asrealsocialist scientists claim. However, in his alternative "Snowball Earth" reality, CO2 was at 300,000 ppm (only 30% of our atmosphere). And, lo and behold, such amounts could not so much as melt a single ice cube. -
dmccubbi at 05:56 AM on 26 June 2011Bob Carter’s climate counter-consensus is an alternate reality
Good article and a nice metaphor: "This would be like saying that winter is not colder than summer because a very hot day in winter might happen to have much the same temperature as a very cold day in summer, ignoring all the other days." Thanks for the review, Don -
dana1981 at 05:36 AM on 26 June 2011A Detailed Look at Renewable Baseload Energy
MattJ - there's a big difference between releasing carbon which is already circulating in the natural carbon cycle, and releasing carbon from fossil fuels. As for "where is the 100%?", you answered that yourself. Some of the plans and case studies include gas turbines - which as the article notes, can burn renewable bio materials - and some don't. I have to say, it surprises me how many commenters have a "can't do" attitude. -
Stephen Leahy at 05:28 AM on 26 June 2011A Detailed Look at Renewable Baseload Energy
It's also early days for renewables. A mere pittance has been invested in R&D compared the the multi-billions nuclear energy has received from governments since 1950. -
okatiniko at 05:27 AM on 26 June 2011Sea Level Hockey Stick
les : the replication of hockey sticks by random pseudo proxies has been made by several authors, including Mc Shane and Wyner . It is nowhere said in deep climate that random pseudo proxies do not generate hockey sticks, the only controversy is about how far it affects reconstruction methods. I must admit that I am not competent enough to say who is right, and you aren't probably either.
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