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gv at 13:46 PM on 18 May 2009Does ocean cooling disprove global warming?
#2 response [ Response: I believe Argo is designed to have more extensive coverage. The Argo homepage talks about how sparse measurements were before the Argo network was deployed (although they might be talking themselves up a bit on this page). ] So argo is at least designed to be a more accurate and extensive mesurement. So if argo dat is not coinciding with XBT data wouldnt it make sense to more rigorously question XBT data, rasther than the other way around ??? look i know nothing about argo or XBT or any of this- just trying to apply Popper and socrates a bit and see where it leads us -
Steve L at 12:57 PM on 18 May 2009Does ocean cooling disprove global warming?
I feel woefully undereducated on this and should read the papers. But ... why tell you when I can show you?: The most striking feature of Figs 1 & 3, to me, are the seasonal pattern of ocean head content. The peak occurs in Autumn (southern hemisphere) every year. I imagine this is because most of the ocean is in the southern hemisphere and so has completed the half year in which it receives most of its solar energy. Two lazily considered ideas relevant to the discussion of the previous post: (1) measurement has to be pretty good for both Argo and XBT to resolve this signal (the signal is much stronger than noise on a seasonal scale), but it looks like Willis reconstructs this feature better than Leuliette in Fig 3; (2) if the total ocean heat content (estimated from the upper layer) can fluctuate this greatly among seasons, then surely it should be able to deviate from a monotonic annual increase. Both aspects of the first lazy idea argue for recent global cooling, I guess; the second lazy idea, if valid, would argue against it. Sorry for being so lazy! The other thing, though, that might be worth mentioning, is that steric sea level (Fig 4) doesn't seem to resolve any seasonal cycle. Does this suggest that resolution of the seasonal cycle is a poor criterion for evaluating this stuff or does it mean that Cazenave's method is less reliable?Response: I should've clarified in the figures but Figure 4 shows the steric sea level with the seasonal element removed. This enables you to more clearly determine the trend. Figure 3 does not have the seasonal signal removed. Steric sea level does have a strong seasonal cycle.
In fact, Leuliette 2009 has an interesting discussion on the seasonal signal. They find that there is a strong seasonal signal of 8mm per year due to ocean mass change, peaking in the Northern Hemisphere summer. Eg - ice melt in the north. The steric sea level peaks in the Southern Hemisphere summer as most of the ocean is in the south, with an amplitude of 3.9mm. Both signals cancel each other out somewhat with the resultant global signal being around 4.2mm. -
Dan Pangburn at 12:50 PM on 18 May 2009It's the sun
Ginckgo 382: The assessment using Control Theory described at 380 shows that atmospheric carbon dioxide level change, during the previous glacial period, had no significant influence on temperature change. The logarithmic decline of influence with increased concentration shows that CO2 has even less effect at the higher current level. This is all described further at the pdf linked from http://climaterealists.com/index.php?tid=145&linkbox=true -
gv at 12:31 PM on 18 May 2009Misinterpreting a retraction of rising sea level predictions
oh and yes any hypothesis must be falsifiable that it means that there must be a clear testable means ( now or in the future) wherby you say that if X is true the hypothesis must be false. so how do we falsify AGW. what X must be true for AGW to be falsifiable. -
Dan Pangburn at 12:25 PM on 18 May 2009It's the sun
Gord: What you describe, different ratios of temperature-change/CO2-change at paleo time vs. 20th century, corroborates that CO2 does not drive temperature. Another analysis that looks at atmospheric carbon dioxide level change vs. temperature change can be seen in a video at http://www.climate-skeptic.com/ . Correlation does not prove causation but lack of correlation proves lack of causation. The lack of correlation of the sequence of 30 year long up and down trends of temperature during the 20th century with the smoothly rising temperature proves lack of causation, i.e. that CO2 level did not drive temperature. Measurements made during the last decade also corroborate this. Since 2000, atmospheric carbon dioxide has increased 18.4% of the increase from 1800 to 2000. According to the average of the five reporting agencies, the trend of average global temperatures since 1998 shows no significant increase and for the seven years ending with 2008 the trend shows a DECREASE of 1.8 C°/century. This separation of trends corroborates the lack of significant connection between atmospheric carbon dioxide increase and average global temperature. I wonder how wide the separation will need to get before the IPCC and a lot of others are forced to realize that maybe they missed something. -
gv at 12:18 PM on 18 May 2009Misinterpreting a retraction of rising sea level predictions
re # 2 "The Society keeps members informed on current news and activities through the regular distribution of the bi-monthly Bulletin of the Australian Meteorological and Oceanographic Society." That does not sound like a peer review journal to me. Sounds more like an academy mouthpiece. However, I do not know anything about the journal, this is just what i picked up at their website. re # 9 "Since the expectation of GW is the result of the framework theory, it has to be DISPROVEN to be invalidated." that is not how science works You generate a hypothesis you find supporting data if over the years ANY data is found that disproves the hypothesis. The hypothesis is wrong. or at least that is the scientific metyhod i have been used to in my line of work. Karl popper agrees. -
Ian Forrester at 12:10 PM on 18 May 2009Does ocean cooling disprove global warming?
There is a good discussion on this on Physics Forums: http://www.physicsforums.com/showthread.php?t=311982 Just skip over the posts by Saul. The missing piece in this jigsaw is the amount of heat which is transferred into the deeper ocean. ARGO mostly measure up to about 700 meters. Some floats do go deeper but they are a small percentage of total. I think that most people have a hard time understanding that warm water can sink because simple physics tells them that warm water is less dense than colder water and should float. However, there is another contributing factor to density and that is salinity. As the surface waters warm and evaporate the water that is left becomes slightly more saline. As this keeps on recurring the increased density from evaporation causes an inversion (similar to what happens in lakes) and the surface water sinks to deeper depths carrying heat with it. This would occur on a cyclic basis but I have no idea how long it will take for the water to increase in salinity till it is dense enough to sink. Anyone have any thought on this? -
gv at 11:55 AM on 18 May 2009Does ocean cooling disprove global warming?
Just trying to understand both points of view and to make up my mind..... for starters why was the argo system deployed ? was it more accurate than XBT ? Did it have more extensive coverage than XBT ? was xpt just running out of steam and needed replacement?Response: I believe Argo is designed to have more extensive coverage. The Argo homepage talks about how sparse measurements were before the Argo network was deployed (although they might be talking themselves up a bit on this page). -
Philippe Chantreau at 10:25 AM on 18 May 2009Does ocean cooling disprove global warming?
Nice overview John. I still don't see where the logic is to say that oceans should be warming uniformly, without any kind of noise. -
Patrick 027 at 05:10 AM on 18 May 2009It's the sun
ginckgo - good point. Dan Pangburn - Well, I don't see the value in using control theory if climate science has already advanced in every way beyond where control theory would be helpful. If control theory works, it must be more sophisticated than as suggested by your example, because you're results are incorrect. "Repeatedly during the last and previous glacial periods, a temperature increasing trend changed to a decreasing trend and vice versa. This is not possible if there is significant net positive feedback from temperature." This ignores the possibility that the temperature variations were externally forced. Positive feedback causes a cyclic variation in response to a cyclic forcing to be larger in amplitude than otherwise. It also ignores that feedback mechanisms work differently on different time scales: In the shortest time periods, climate change response to a high frequency forcing tends to be damped by thermal inertia (heat capacity), although if modes of internal variability (unforced fluctuations, such as QBO, ENSO...) resonate somehow with forcing ...(?) - but also, in doing analysis, one can not assume that any variation within some interval of the spectrum of frequencies is actually being excited by external forcings with those frequencies, because, though alterable by external forcings, some internal variability will occur without any fluctuating forcing (QBO, ENSO, NAM and SAM, AMO? etc...). When temperature does change in response to external forcing, nearly instantaneous positive feedbacks include water vapor. Clouds will also be a nearly instantaneous feedback, but it is not so clearly and/or generally positive. Over longer periods of time, seasonal snow can be a positive feedback. Sea ice changes can be a positive feedback. Generally over longer timescales (especially during cooling, because snow can only accumulate as rapidly as it precipiates, whereas melting and distingration of ice sheets can occur faster (with uncertainty)), glaciers and ice sheets, and changes in vegetation (forests vs grasses vs deserts, etc.) can be positive feedbacks. Changes in the more rapid portions of the carbon cycle (soil, vegetation, atmosphere, oceans) can also be a (positive) feedback. BUT over even longer periods of time, the very slow CO2 removal from the atmosphere by chemical weathering and geologic storage by generally slow organic C burial tends to balance geologic emissions of CO2. Changes in geologic emissions and changes in topography, land surface composition, and geography can force the atmospheric CO2 level, but resulting changes in climate tend to cause changes in chemical weathering so as to reach a new equilibrium CO2 level; furthermore, chemical weathering tends to act as a negative feedback to climate forcing by other causes (with some complexities - it depends on geography and rock composition, etc...). "With this knowledge and the knowledge of the logarithmic decline in effectiveness of added atmospheric carbon dioxide it is obvious that there is no significant net positive feedback from increased average global temperature." The logarithmic proportionality of radiative forcing to CO2 level has no direct bearing on the climate sensitivity to radiative forcing. "This IPCC prediction is probably still high because of faulty cloud parameterization, etc." Actually, cloud feedback in climate models is small and ranges from negative to positive; the dominant positive feedbacks are water vapor and albedo. -
ginckgo at 19:56 PM on 17 May 2009It's the sun
How does the likely possibility that CO2 has not caused of every single change in climate in the past, preclude it from being a significant cause at the moment? You guys do see the fallacy in insisting that, considering the complexity of the system, right? -
Gord at 19:32 PM on 17 May 2009It's the sun
Dan Pangburn - The Vostok Ice core data also show that the relationship between the Earth's temp and CO2 levels is probably linear relationship. I once plotted the the Vostok graphs on a computer using AutoCad and measured the change in temp vs the change in CO2 levels. Although this was just a crude approximation because I did not use actual data (just the graphs and only at a few points), the results showed that the change in CO2 divided by the change in temp was a constant (or very close). Because the change in CO2 divided by the change in temp is a derivative and produced a constant, this indicates that the equation describing the the relationship between temp and CO2 is probably linear. -------------------- The following is a re-post of what I posted on another forum a few years ago: --------------------------------- --------------------------------- The IPCC uses this formula for an approximate calculation of CO2's relationship to changes in W/m^2 forcing EXCLUDING AMPLIFICATION(I will call it delta F). delta F = 5.35 LN( C/Co) where LN is the natural logarithm, Co is the CO2 in ppm for a starting point, C is the CO2 in ppm for analysis and F is the forcing in W/m^2. The IPCC also uses a figure of 0.297 deg C change per each W/m^2. If we multiply both sides of the formula by 0.297 we obtain the relationship: delta T = 1.59 LN ( C/Co) where delta T is the change in temperature (in deg C). ------------------ A way to determine the "approximate" amplification factor that the IPCC uses for CO2. If the CO2 has gone from 1ppm to 290ppm (guesstimate for pre-industrial time) then delta T = 1.59 LN (290/1)= 9.02 deg C. The AGW'ers say the Earth has warmed by about 33 deg C due to the Greenhouse effect, so 33/9.02 = 3.66 must be the Maximum amplification factor possible. ------------------------ The Past and Future of Climate by David Archibald http://www.warwickhughes.com/agri/pastandfuture2.pdf Atmospheric CO2 vs Earth Temperature During the Ice Ages The Ice Ages (Figure 7) shows the biggest variances (interpolating) for Temp is 13 deg C (+3 to -10) and CO2 is 120ppm (180 to 300). This is about 330 thousand years ago. Using the above formula delta T = 1.59 LN (300/180)= 0.812 deg C The ratio for Actual CO2 change to Actual Temp change is 120ppm/13 deg C = 9.23 The "amplification factor" for CO2 would have to be 13/0.812 = 16.0!! Now look at a portion of the graph where the changes are less (eg. 215 thousand years ago) The variances are..Temp variance is about 3.2 deg C (-1.8 to -5) and the CO2 variance is about 30ppm (230 to 260) Using the above formula delta T = 1.59 LN (260/230)= 0.195 deg C The ratio for Actual CO2 change to Actual Temp change is 30ppm/3.2 deg C = 9.38 And, the "amplification factor" for CO2 would have to be 3.2/0.195 = 16.4 ! Clearly, the "amplification factor" varies so much, it is pure fiction....3.66 for the "Greenhouse Effect" vs about 16 for the Ice Ages! But, the MOST IMPORTANT thing this analysis shows is that, the CHANGE IN CO2 divided by CHANGE IN TEMP is really a CONSTANT (9.23 vs 9.38). The CHANGE IN TEMP divided by CHANGE IN CO2 is a DERIVATIVE that produced a CONSTANT. This means that the mathematical equation relating CO2 and TEMP HAS TO BE A LINEAR FUNCTION or close to it. Further, evidence of the LINEAR relationship is very apparent in the cyclical nature of CO2 vs TEMP in the Ice Ages graph. First, TEMP leads CO2 by about 800 years....CO2 follows TEMP LINEARLY! We know that the SUN's activity is cyclical in nature and CO2 absorbtion and release by the Oceans is governed by temperature. Temperature DRIVES CO2 production.....simple CAUSE and EFFECT. --------------------- If CO2 were assumed to "somehow" cause the the temperature changes (as the AGW'ers want us to believe) then: 1. It would HAVE to LEAD temperature not FOLLOW it. 2. The CO2 production (volcanos, bio-mass decay etc) would HAVE to occur in a "cycle" that produced the same sequence of events to produce the CO2 with the same regularity over about 400 THOUSAND YEARS!!! I would suggest that the probability of this happening is about ZERO. -------------------------- -------------------------- End of the re-post. Dan have you looked into this as well? -
Steve L at 15:07 PM on 17 May 2009Ice age predicted in the 70s
I was struck by this week's skeptic article (by David Deming in "The American Thinker"), [http://skepticalscience.com/article.php?a=2327] finding it both laughable and inspiring, and it drew me back to here. One thing that surprised me a bit was Deming's claim that we don't know what causes ice ages. I thought it was Milankovitch cycles mostly (Deming says Ike Winograd disproved that). With the google I only found a Wunsch abstract [http://tinyurl.com/qg3bgw] that says orbital changes only explain 20% of the variance in climate records studies. Anyway, I'm curious to learn more about our understanding of ice ages. -
Dan Pangburn at 10:58 AM on 17 May 2009It's the sun
The physics is the same, of course. However, most in the Climate Science Community are unaware of the science (which includes the physics) of Control System Theory. Control Theory should more properly be called Control Science, or better yet, Control Engineering since it has multiple practical common applications such as automobile cruise control, aircraft autopilot, missile guidance, electronic circuits, etc. etc. Control Theory is usually taught in mechanical, electrical and aeronautical engineering graduate school and is not in the Climate Science curriculum. Those who understand Control Theory have the knowledge to recognize that earth’s climate can be evaluated as a dynamic system with feedback. In the analysis, all of the minutia of weather and climate, whether known or not, get lumped together (in the control/plant which, by definition, includes all factors that influence average global temperature). The output, as archived in the ubiquitous Antarctic ice core data is extracted as temperature anomalies. Repeatedly during the last and previous glacial periods, a temperature increasing trend changed to a decreasing trend and vice versa. This is not possible if there is significant net positive feedback from temperature. It is not necessary to explicitly describe any of the factors in the control/plant (as used in Control Theory) to determine whether net feedback, if significant, is positive or negative. The average global temperature does not need to be known accurately just reasonable valid relatively. With this knowledge and the knowledge of the logarithmic decline in effectiveness of added atmospheric carbon dioxide it is obvious that there is no significant net positive feedback from increased average global temperature. Atmospheric/Oceanic General Circulation Models, AOGCMs, include the circulation effects of atmosphere and ocean. Climate Scientists use these global climate models to predict future climate. Although there may be no explicit input parameter for feedback in the AOGCMs, when used to predict future climate they incorporate features that result in significant net positive feedback. Without significant net positive feedback AOGCMs do not predict significant global warming. Zero feedback results in 1.2°C from doubling of atmospheric carbon dioxide per p631 of ch8 of UN IPCC AR4 (this 5.84 mb pdf file can be viewed and/or downloaded from http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch08.pdf ). This IPCC prediction is probably still high because of faulty cloud parameterization, etc. Unless overwhelmed by other factors, an insignificant temperature increase of less than a degree Celsius, most of which has already taken place, is expected from doubling atmospheric carbon dioxide from the pre-industrial-revolution level of about 275 ppmv. See the pdf linked from http://climaterealists.com/index.php?tid=145&linkbox=true for a more extensive discussion and graphs. -
Quietman at 06:56 AM on 17 May 2009Volcanoes emit more CO2 than humans
This is cut and paste from the original article that I can't locate: Although scientists understand the mechanics of El Nino, its origins have yet to be determined. The new theory [of the cause of El Nino] suggests that the primary mover behind El Nino is hot magma welling up between tectonic plates on the Pacific sea-floor. The upwelling magma heats the overlying waters enough to affect the ocean surface, initiating the cascade of events that brings on the wrath of El Nino. This, while not the same source says the same thing: Hot Vents and Global Climate Every two to seven years a climatic disturbance brings floods to California, droughts to Australia, and famine to Africa . Known as El Nino, it is essentially a warming of surface waters in the eastern Pacific near the equator. Although scientists understand the mechanics of El Nino, its origins have yet to be determined. Most believe that the interaction between the atmosphere and the sea somehow generates this climatic disturbance that wreaks havoc upon those regions of the world that lie in its path. But now a new theory on the origins of El Nino has been proposed and, surprisingly, it has very little to do with the atmosphere or the sea. The new theory suggests that the primary mover behind El Nino is hot magma welling up between tectonic plates on the Pacific sea-floor. The upwelling magma heats the overlying waters enough to affect the ocean surface, initiating the cascade of events that brings on the wrath of El Nino. http://www.platetectonics.com/book/page_20.asp -
Quietman at 06:34 AM on 17 May 2009Volcanoes emit more CO2 than humans
I give up. When I first looked to find the cause there was one page of search results now there are hundreds. -
Quietman at 06:28 AM on 17 May 2009Volcanoes emit more CO2 than humans
Here is a different view: As far as deep-ocean vents modifying the ocean temperatures, researchers now think that this source of heat does contribute to the long-term evolution of the ocean state. We can trace the chemical signatures of sea floor venting carried for quite a distance in the deep currents. Those traces are useful for estimating the deep flows, which are difficult and expensive to measure directly since they are so slow. However, we observe that the heating due to deep venting becomes diluted in the vast reaches of the abyssal ocean and therefore does not make quick changes in the ocean state. These affects are felt over decades or centuries, not on the relatively rapid time scale of El Niño. It is indeed tempting to look for simple causes of complex oscillations like the El Niño cycle. Unfortunately (or perhaps fortunately for those of us who like scientific challenges), it seems that the ocean-atmosphere system is well capable of generating these oscillations on its own, and the task now is to understand how this happens. Volcanoes and sea floor venting are part of the slowly changing background state to which phenomena like El Niño are added, and they increase the complexity of the task. http://www.pbs.org/wgbh/nova/elnino/resources/elninofaq.html Sorry, I still can't where the hypothesis is spelled out. -
Quietman at 06:16 AM on 17 May 2009Volcanoes emit more CO2 than humans
The real cause of El Ninos is still obscure. However, the recent discovery of over 1,000 previously unmapped submarine volcanos rising from the seafloor in the eastern Pacific may lead to El Nino's source. The synchronous eruption of, say, 100 of these volcanos might warm the ocean around Easter Island a tad---just enough to warm the atmosphere above a bit---resulting in a shift of the high pressure area. The area of intense volcanic activity covers 55,000 square miles of sea floor where the Pacific and Nazca plates are separating. In addition to the active volcanos, many plumes of 800°F water gush from the sea floor in this area. The volcano-El Nino link is, therefore, not so far-fetched. (Nash, Nathaniel C.; "Volcano Group in Pacific May Cause El Nino," Pittsburgh Post_Gazette, February 14, 1993. Cr. E. Fegert) Comment. If submarine volcanos do cause the El Ninos, and the El Ninos are periodic, the submarine volcanism would have to be periodic, too. This implies an unrecognized rhythm in the earth's internal fires. - http://fusionanomaly.net/elnino.html -
Quietman at 06:12 AM on 17 May 2009Volcanoes emit more CO2 than humans
Sometimes, and for reasons not fully understood, the trade winds do not replenish, or even reverse direction to blow from west to east. When this happens, the ocean responds in a several ways. Warm surface waters from the large, warm pool east of Indonesia begin to move eastward. Moreover, the natural spring warming in the central Pacific is allowed to continue and also spread eastward through the summer and fall. Beneath the surface, the thermocline along the equator flattens as the warm waters at the surface effectively act as a 300-foot-deep cap preventing the colder, deeper waters from upwelling. As a result, the large central and eastern Pacific regions warm up (over a period of about 6 months) into an El Niño. On average, these waters warm by 3° to 5°F, but in some places the waters can peak at more than 10°F higher than normal (up from temperatures in the low 70s Fahrenheit, to the high 80s). In the east, as temperatures increase, the water expands, causing sea levels to rise anywhere from inches to as much as a foot. But in the western Pacific, sea level drops as much of the warm surface water flows eastward. During the 1982-83 El Niño, this drop in sea level exposed and destroyed upper layers of coral reefs surrounding many western Pacific islands. http://earthobservatory.nasa.gov/Features/ElNino/elnino.php Yeah, I know that you really did want to know that either. -
Quietman at 06:08 AM on 17 May 2009Volcanoes emit more CO2 than humans
ps Dr. S.D. Meyers and Dr. J.J. O'Brien. "Variations in Mauna Loa carbon dioxide induced by ENSO" Which I wanted to link for you has been surpressed by the new regime but is worth reading if you can find a bootleg copy. -
Quietman at 06:02 AM on 17 May 2009Volcanoes emit more CO2 than humans
Note "Study: Volcanoes Unleash El Niño" http://dsc.discovery.com/news/afp/20031117/elnino.html is about the symptoms, not the cause. -
Quietman at 05:55 AM on 17 May 2009Volcanoes emit more CO2 than humans
As I said chris, When I relocate the article I will post it here. I had not realized just how misunderstood this science was. This explains in part how the ocean drives the atmospheric currents known as Trade Currents. http://www7.nationalacademies.org/opus/elnino.html or http://www7.nationalacademies.org/opus/elnino_PDF.pdf It does not explain the thermocline fully however so I'll try to keep finding something on it's root cause that can be linked to. -
Patrick 027 at 03:16 AM on 17 May 2009It's the sun
"Feedback Control Theory " How is that different from climate model physics? -
Gord at 22:52 PM on 16 May 2009It's the sun
TrueSceptic - Yes, he is a sceptic. He is also a male, a human being, a consumer, a professor, wears pants, etc....does that hold any particular significance for you? Like I said... "I certainly agree with you that Feedback Control Theory is totally lacking in the field of Climatology." It seems that you somehow totally missed the point,...I was commenting about the curriculum of Climatology as discussed by Dan Pangburn. It should be evident to you that field of Climatology includes some "AGW sceptics"....they all share the same curriculum. -
Mizimi at 20:23 PM on 16 May 2009It's the sun
Hmmm...astonishly honest as well.... -
TrueSceptic at 10:43 AM on 16 May 2009It's the sun
373 Gord, _I remember reading an article by a leading Climatogist (a Ph.D and AGW sceptic) that had "discovered" that Feedback and Control theory was being taught in the building next to his....the faculty of Electrical Engineering. He briefly described a simple single feedback loop control system. He seemed amazed that this technology even existed. He certainly had no idea that feedback and control system concepts have commonly been used electronic circuit designs since the invention of the vacuum tube._ Really? This is astonishing ignorance, and did you say he's a "sceptic"? -
Patrick 027 at 10:00 AM on 16 May 2009Arctic sea ice melt - natural or man-made?
"A lot for you, nothing to the Earth. Everything is relative. " It was an analogy, Quietman. There are actually over 700 billion tons of C in the atmosphere in the form of CO2. Anthropogenic emissions could easily double atmospheric CO2. On a per molecule basis, CH4 is certainly a stronger greenhouse gas than CO2, and CO2 may be stronger than H2O vapor, but there's a lot more H2O in the atmosphere than CO2 (although there are variations in concentration such that H2O has less effect than it would if it were well-mixed), and much more CO2 than CH4. Etc. There is much less of any of these than there are N2 and O2, but N2 and O2 have little effect on LW radiation. Of course, the per molecule strength of a gas depends on overlap with other gases and with itself - these things depend on the concentration; for example, the radiative forcing of CO2 is roughly logarithically proportional to CO2 amount within a range of values. ------ "The science isn't settled." Depends on which part of the science. I never claimed that ever last piece of the puzzle had been fit together. What we know: Human activity has caused a dramatic and rapid increase in atmospheric CO2 and is still adding to that, pushing the atmospheric CO2 level to well above levels seen for hundreds of thousands of years. Human activity has also added other greenhouse gases. The mechanism of radiative forcing of climate is settled. Changes in greenhouse gas levels have made important contributions to climate change in the past, both as externally forced changes (volcanic activity and other geologic emissions, tectonically/mineralogically forced changes chemical weathering, changes in the C cycle due to biological evolution) and as feedbacks (orbitally-forced glaciations/deglaciations and monsoon changes, changes in solar TSI over 100s of millions of years, biological evolution, other climate changes). Water vapor and snow and ice albedo are important positive feedbacks. The best estimate of climate sensitivity from physics, paleoclimate, and the historical record is about 3 deg C per doubling of CO2 (or its radiative equivalent, adjusting for efficacy of different forcing agents), give or take roughly 1 deg C or so. Climate sensitivity from the paleoclimatic record can be problematic because climate sensivity could vary as a function of climate itself (and perhaps geography/geology and biological evolution); the climate sensitivity determined by greenhouse gas changes between preindustrial time and the last ice age may be larger than the climate sensitivity now because there is less ice sheet area available to melt/disintegrate and the snow and ice is more confined higher latitudes; however, Hansen's calculation of a 3 (+/- 1 ?) deg C for the radiative equivalent of a doubling of CO2 is actually calculated from the radiative forcing of greenhouse gases, ice sheets, aerosols, and land albedo changes from vegetation, and thus the climate sensitivity to greenhouse gas forcing and other anthropogenic forcings could be greater than that, as any ice sheet and vegetation responses would be feedbacks in AGW context. (Off hand I am not sure if sea ice albedo was included in Hansen's forcings; I think it was not. I inferred that nnow cover, along with water vapor and clouds, were treated as feedbacks. Snow cover would have extended to lower latitudes in the ice ages, but some higher latitude snow cover would be replaced by ice sheets, and the total area of seasonal snow might actually have been less (??), although it would have been at lower latitudes...)); however, there is evidence for a relationship even farther back in time than the last several ice ages, going back hundreds of millions of years; the Earth has been both warmer and cooler in the past. A persuasive case that there is some strong negative feedback missed by climate models is lacking. There are also both largely settled and unsettled aspects to what climate change means on the regional level. Greenhouse effect-driven warming will tend to warm the surface and troposphere but cool the upper atmosphere; solar forcing tends to warm both or cool both; volcanic aerosols can cause warming in the stratosphere while cooling the surface and troposphere. Any surface and tropospheric warming will tend to be enhanced in the mid-to-upper troposphere at lower latitudes (due to a moist adiabatic lapse rate feedback) and at higher latitudes near the surface (due to snow and ice albedo feedbacks and perhaps alsob because of the relatively larger vertical static stability in the air)(except, at least at first, in the Southern hemisphere due to the Antarctic Ice Sheet's stability, cold upwelling water driven by winds, and the dominance of water and lack of land in southern midlatitudes). Sea level will rise from thermal expansion of water and from melting glaciers and land ice (and not just until 2100); it will not be perfectly the same everywhere because regional sea level variations are caused by wind and temperature variations. Generally, a greater portion of precipitation will come in shorter time intervals at any given location. There is some expectation that midlatitude storm tracks will shift poleward, with drying trends on their subtropical flanks. Depending on how much more moisture the soil can hold in the spring from winter melt, there may be significant drying in midlatitude continents in summer in particular if extra precipitation in the winter is lost to runoff. There are significant costs to adapting to large, rapid, sustained changes into relatively unfamiliar conditions; if taken far enough, such change leads to mass extinctions. Ecosystems are stressed by such changes. The economy is an ecosystem and it depends in part on the larger natural ecosystems. Human society is obviously capable of rapid evolution, but this can still involve much pain, and that can be amplified by an evolved expecation of modern comforts, as well as population growth and politics (somewhat unlike in the stone age, it is not a simple matter to pack up one's belongings and just migrate; even if you are poor enough to carry all you own, borders and property rights get in the way). Buildings and infrastruture have been designed for conditions and will need adjustments. Agricultural productivity will decrease in the tropics; it may increase at first at higher latitudes, but only up to a point; tropical conditions are not kind to some valued food crops; the growing season cannot get any longer than a full year and growing season quality is important. Some crops are photoperiod sensitive. Breeding new crop varieties takes time and effort. There is great concern about fresh water availability as glaciers melt (regularity is important, not just total amount). Warming could increase risk and spread of some tropical diseases. Loss of biodiversity is a cost; biodiversity is a resource for new crops, drugs, etc. There is a great concentration of people near sea level. Uncertainty in climate change could itself be a cost because uncertainty hinders planning (there will always be uncertainty in the future climate, human effects or not, but presumably the total uncertainty is greater when there remains natural fluctuation and uncertainty in climate response to anthropogenic forcing). Even if adaptation were easier than mitigation (although it is not an either-or issue but a question of how much of each), it makes sense that the benificiaries of climate-change causing activities should pay the costs of climate change (the market response to that imposed price signal would tend to favor mitigating economic pathways - efficiency and clean energy, etc.). Even with various levels of uncertainty, there are actions for which an actionable level of inteligence will have been met. Even decades ago, it made sense to invest in clean energy and energy efficiency technology, at least to have it available to deploy with sufficient pace, as an insurance policy for the risk that global warming would be a problem. We have reason now to actually impose a price signal on emissions (or some other policy) to shift the economy towards greater demand of and investment in clean energy and energy efficiency as well as other emissions-reducing pathways. I do agree that there is room for debate about how large that price signal should be, because the science is not FULLY settled (it is likely it never will be FULLY settled). -
Mizimi at 05:16 AM on 16 May 2009Water vapor is the most powerful greenhouse gas
Anybody read this http://www.landshape.org/dokuwiki/doku.php?id=introduction which is an outline of a new climate 'theory' by Ferenc Miskolczi (ex NASA mathemetician) and if so...any comments? -
Steve L at 05:15 AM on 16 May 2009A broader view of sea level rise
#32 Ron: Hmmm, I thought you were asserting before that Argo disproved the concensus understanding of AGW. Now it seems you are saying that Argo and a bunch of other stuff suggest to you that AGW won't be "catastrophic". That seems like progress to me, but maybe I never knew what you meant. If you define "catastrophic" I'll be more likely to understand your perspective now. John, I thought I remembered a post of yours on effects of the solar cycle on temperature but I couldn't find it. Is it still around somewhere?Response: Here's the post on solar cycles. Note - it cites a recent paper that finds the solar cycle imposes a 0.18C signal on the temperature record. There are other papers that find around a 0.1C signal. I've since come to think its more likely to be the 0.1C signal as the strong signal Tung finds goes out of phase as you go further into the past. -
Mizimi at 04:57 AM on 16 May 2009It's the sun
Relative to the 'it's the sun' thread.... icecap.us/images/uploads/REVISITINGTHEANALOGUEFORTHECOMINGICEAGE.pdf - presents an interesting view on AGW models and the results obtained from them. -
chris at 04:15 AM on 16 May 2009A broader view of sea level rise
re #28 1. CO2 variability. a. Contrary to your assertion Ron, enhanced CO2 emissions during the last couple of decades do seem to be associated with enhanced atmospheric CO2 accumulation. We can inspect the atmospheric CO2 data: http://www.esrl.noaa.gov/gmd/ccgg/trends/ and find that the averaged yearly CO2 accumulation in the atmosphere for the decade 1990-1999 was 1.50 ppm per year and for the (not quite) decade 2000-2008 was 1.98 ppm per year. b. It shouldn’t be hard to “swallow” a relatively narrow range of CO variability since that’s what the evidence and our understanding of the carbon cycle indicates: (i) In a stable climate system with no change in external forcings (no volcanoes or, changes in solar output, greenhouse gases etc), there will still be some year on year variation in the atmospheric CO2. For example, in or shortly after El Nino years the CO2 levels rise due to heat and moisture stress in the tropical rainforest belts; in or after La Nina's tropical forests recover their growth and CO2 levels in the atmosphere drop somewhat. However that will just yield variation around a rather steady level. Atmospheric CO2 levels can't undergo extended continual unforced rises and falls without some sort of phenomenon external to the climate system, because there is a pretty fixed amount of accessible carbon in the short term carbon cycle. So on the decadal, centennial, millenial timescale the atmospheric CO2 levels aren't expected to change that much. In fact it's an indication of the rather steady nature of the accessible carbon in the short term carbon cycle that over tens and hundreds of thousands of years through numerous glacial-interglacial cycles, the atmospheric CO2 levels tend to return to interglacial values within a few ppm of 280 ppm. If one of the carbon pools (oceans/atmosphere/terrestrial) is perturbed, then the carbon will be redistributed. If deforestation and other land use changes reduces the carbon stored in the terrestrial pool and the atmospheric (and ocean) levels will rise. That seems to be the origin of much of the enhanced accumulation of CO2 in the atmosphere through the 19th century [N2O and methane rise follows a similar trajectory – see MacFarling Meure paper cited in post #23; see also the link on land use contributions to enhanced CO2 levels in Philippe Chantreau’s post #25]. Obviously if the climate system isn't stable and external forcings change (variation in solar output/major periods of volcanic activity and so on) then atmospheric CO2 levels will respond somewhat. That seems to be the origin of the small reductions of atmospheric CO2 through the period of the LIA….and so on… 2. You’ve misrepresented my statement:”It's very easy to calculate that within a climate sensitivity right in the centre of the likely range (3 oC of warming per doubling of atmospheric CO2), the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively.”
by contracting it to "the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively." …and then engaged in trashing your own misrepresentation! The point is that all else being equal, a rise in atmospheric CO2 from 286 ppm (1850) – 309 ppm (1940) should produce a surface temperature rise at equilibrium of around 0.3 oC within a climate sensitivity of 3 oC of warming per doubling atmospheric CO2. Since a large amount of science indicates that is the “best estimate” for the climate sensitivity under current conditions, we shouldn’t be surprised to find that the world seems to have warmed significantly during this period, with increasing effects on sea levels, glacial recession and so on. Of course in the real world all else very likely isn’t equal. A small enhanced solar forcing in the first half of the 20th century likely contributed to warming. Very significant volcanic activity in the late 19th/early 20th century, “knocked back” temperature rises temporarily…and so on. But we can hardly assert that temperature rises won’t follow from enhanced greenhouse gas levels, when the most likely scenarios from scientific evidence/analysis indicates that they should! And it’s not about “pro-AGWers” whatever that might mean – it’s about the science and its associated evidence. Small persistent changes in greenhouse gas levels are expected to produce re-equilibration of the climate system towards new temperatures, not because “pro-AGWers” “think” so, but because that’s what the evidence, and our scientific understanding of the greenhouse effect indicates. ..and a 9 ppm change in atmospheric CO2 is certainly measurable! -
NewYorkJ at 03:55 AM on 16 May 2009A broader view of sea level rise
Ron Cram, You write "The assessment is also based on the climate sensitivity estimates by Schwartz and Chylek, Chylek's work on aerosols, Spencer's identification of a hew negative feedback over the tropics he identified as Lindzen's Infrared Iris Effect, and others." These assessments haven't held up too well. Comment on Chylek/Lohmann: http://www.clim-past.net/5/143/2009/cp-5-143-2009.html Basically, if you do some severe cherry-picking of data, you can find a lower climate sensitivity (or a much higher one as Annan illustrates). Comment on Scwhartz: http://www.jamstec.go.jp/frcgc/research/d5/jdannan/comment_on_schwartz.pdf As a result, Schwartz revised his estimate up about 50%, although not all the issues Annan et al found have been addressed. http://www.ecd.bnl.gov/steve/abstracts/HeatCapacityResponse.html Lindzen's hypothesis hasn't withstood the test of time, and has gone through various revisions. When one piece of data refutes a claim, it morphs until another piece is falsified. Chris Colose exposes some key problems with Lindzen's latest claims, and there's some clear evidence that Lindzen has a problem admitting error. http://chriscolose.wordpress.com/2009/03/31/lindzen-on-climate-feedback/ As for Spencer, what can I say? The UAH dataset has been revised upward more times than I can count. At one time he used his own flawed data to claim everyone else was wrong. The fact that he's working hard to find a negative feedback shouldn't surprise anyone. -
NewYorkJ at 03:40 AM on 16 May 2009A broader view of sea level rise
Ron Cram, ""credibility" is not a factor under consideration" Really? You seemed to understand that a journal's reputability is important, given your comment in #4: "Roger Pielke, the ISI highly cited climatologist I referenced above" What changed? It's not really a choice for contrarians to publish in E&E. They do so because their studies are usually very weak and can't pass a single independent peer review in dozens of reputable journals. Keep in mind that this doesn't imply anything peer-reviewed is correct (not the specific purpose of a peer-review), but something that can't pass ANY valid peer-review is highly suspect. While it's plausible that a biased reviewer exists somewhere in some journal, alleging all of these journals are corrupt is a rather dubious charge that tends to hurt the credibility of the accuser, especially when they end up publishing a study in an uncited demonstrably political journal of like-minded skeptics. Publishing in E&E helps give them the false appearance of a better level of credibility than their study deserves - seemingly better than just posting it on their website. If you're a stickler for ad hominens, Climate Audit is the last place one would want to go. The individual of that site spends more time slinging mud at reputable scientists (the ad hominens you're referring to) than doing actual objective research, and your link is evidence of that. Also, your link does not support your claim of reviewer bias, as is generally the case with McIntyre's ramblings. Good scientists need to be able to acknowledge errors and move on without constantly alleging corruption and conspiracy from those who dare challenge them. McIntyre consistenly fails to meet this criteria. If you say that scientists aren't supposed to be advocates, by this criteria, what contrarian scientists would still exist? -
Patrick 027 at 03:06 AM on 16 May 2009It's the sun
Re 372 - so you mean oxygen can indirectly cause cooling by affecting something else. Well of course, I have been aware that rising oxygen could lead to cooling by reducing the methane levels; however, I suspect this is a less significant effect once oxygen reaches some level of abundance and when methane's role becomes secondary to CO2 in climate-regulating greenhouse gases (except for short-term perturbations) - as far as I am aware, the O2 driven cooling by methane loss is thought to be potentially important in some Proterozoic ice ages, but I haven't heard anything about it being implicated in Phanerozoic ice ages. My impression has been that during the Phanerozoic, oxygen levels have not varied by an order of magnitude or more - instead reaching a peak of ~ 30 % or so some time in the Paleozoic (couldn't get much higher without forest fires consuming it), and it's now about 20 %, ... -
Ron Cram at 01:51 AM on 16 May 2009A broader view of sea level rise
NewYorkJ, you are correct to think most researchers would prefer to publish in journals with a higher Impact Factor. I think I should explain why scientists sometimes choose to publish with E&E. Perhaps you have already heard the charge that skeptical papers are not well received by many journals. In most cases it has to do with the reviewers the editors chooses to review a paper. If you want, I can probably find advocacy quotes from editors of these other journals that would prove their motivation. It is a shame really, because scientists are not supposed to be advocates. I want to give you an example of what researchers are up against. Steve McIntyre, who has published in GRL and other journals, writes about a rejection notice he received from International Journal of Climate. http://www.climateaudit.org/?p=5978#comment-341365 Read Steve's comment and then a few comments following. You will begin to get a flavor of the kind of nonsense that goes on. -
Ron Cram at 01:28 AM on 16 May 2009A broader view of sea level rise
Steve, I did read what Chris has written. I am not freaking out. I pointed out a few of the weaknesses with his argument. I hadn't the time then, or now, to deal with all of them. Your assessment that I have stepped back from my original position regarding Argo requiring a reconsideration of AGW theory is not correct. Loehle points out that there are reasons to question Argo data and I can accept that. But in my mind, the full accumulation of data is contrary to the claim AGW will be catastrophic. Argo is a very strong element of that but it is not alone. The assessment is also based on the climate sensitivity estimates by Schwartz and Chylek, Chylek's work on aerosols, Spencer's identification of a hew negative feedback over the tropics he identified as Lindzen's Infrared Iris Effect, and others. I have not found anything Chris has written as compelling. The only item you offer me is one I cited first and then Chris quoted back to me. It is one thing to be able to look up the numbers and another to be able to understand what they mean. A "pro-AGWer" is shorthand for a climate alarmist- one who strongly supports AGW theory. I would think the context would make that clear. -
Ron Cram at 01:10 AM on 16 May 2009A broader view of sea level rise
NewYorkJ, your attack on the editor of E&E and Loehle's paper is completely ad hom. I'm sorry you do not understand that. In science, "credibility" is not a factor under consideration. The scientific method requires results to be reproduced. If results are reproducible, they are confirmed. If they are not, the paper is rejected. It is that simple. -
chris at 23:01 PM on 15 May 2009Volcanoes emit more CO2 than humans
Re #219 Shouting insults isn't a substitute for careful and clear discourse Quietman. It's obvious that the articles that explore possible relationships between explosive volcanic eruptions and ENSO (see my post #218), indicate that it is the effect of eruptive aerosols on radiative forcing that can affect the ocean circulation in the subsequent short periods. If you've got references to scientific papers that indicates that geothermal heat from subduction zones influences ocean currents in the manner that you are asserting then why not simply list them here. And can you remind us what "That government site that posted a hypothesis for the volcanic nature for the root cause for ENSO" is? Which specific government site? -
Gord at 15:48 PM on 15 May 2009It's the sun
Dan Pangburn - I read your pdf (http://climaterealists.com/index.php?tid=145&linkbox=true) with some interest. I certainly agree with you that Feedback Control Theory is totally lacking in the field of Climatology. I remember reading an article by a leading Climatogist (a Ph.D and AGW sceptic) that had "discovered" that Feedback and Control theory was being taught in the building next to his....the faculty of Electrical Engineering. He briefly described a simple single feedback loop control system. He seemed amazed that this technology even existed. He certainly had no idea that feedback and control system concepts have commonly been used electronic circuit designs since the invention of the vacuum tube. I found this both amusing and sad. -
Steve L at 14:48 PM on 15 May 2009A broader view of sea level rise
Ron, what are you doing? Read what Chris is writing -- he's saying that a small, significant amount of warming is expected from anthropogenic emissions between 70-160 yrs ago. True. Why are you freaking out? You seem to have stepped back from your original position regarding Argo falsifying AGW (is that assessment correct?) and now seem to be arguing other things less relevant to the thread. You've pointed out a few instances of things that don't impress you. What responses have you found compelling? Perhaps the first part of Chris' #23 re Loehle? I still haven't read that darned Church 2006 paper, but I suspect that the error estimates broaden out in the most recent years (John COOK's Fig 1 above) due to a 'smoothing' function or Bayesian approach in which subsequent estimates inform prior estimates. That, figures and discussion in "Mystery of Vanishing Ocean Heat", and the last part of NASA's story on Josh Willis suggest to me that grasping for the most recent data from a single data type is a bad strategy for increasing one's understanding. PS. What is a "pro-AGWer"? I for one would rather be considered as someone who tried to reduce AGW. -
NewYorkJ at 14:30 PM on 15 May 2009A broader view of sea level rise
"The rate of sea level rise has been increasing since the late 19th century. In an upcoming post, we shall look at predictions of future sea level rise." One very recent report, still in draft, projects a ceiling of 6 meters. The ACCE report states: "Rates of sea level rise at least twenty times the current 3.1 mm/yr sustained over more than a century have been measured for the transition to the current warm period following the termination of the last ice age and during some of the warmer intervals of the last ice age. Until improved predictive capability is achieved, this can be regarded as a reasonable upper bound of Antarctica's potential contribution to global sea level. This maximum rate (62 mm/yr) would lead to a 6-meter sea level rise by 2100, but such rates occurred when there was considerably more ice on the planet." http://www.antarctica.ac.uk/met/SCAR_ssg_ps/ACCE.htm I've seen others cap this at 2 meters, probably given the last line in the statement. Sea level rise has certainly been accelerating, but reaching 62 mm / yr seems very unlikely. Sorry for the double post above. -
ginckgo at 13:43 PM on 15 May 2009Volcanoes emit more CO2 than humans
I didn't make myself clear about the change in volcanic activity: I mean only subaerial emissions (not changes in the subduction regime on this short time scale), and usually only the effect of one or two major eruptions. Even then, I doubt that this is the only driver of ENSO. This is mainly because volcanic emissions can alter the weather patterns, and thus change winds, which in themselves influence ocean surface currents. The heat added to small spots on the sea floor is insignificant next to the power of the winds and the thermohaline currents. FYI there is no active subduction zone in the Arctic, only a divergent one (Gakkel Ridge). Not sure about the relevance of inactive ones. The active part of Alaska is to the south, where the north Pacific plate subducts, which is the cause of the Aleutians. The whole plate North America sits on is rotating counter-clockwise. This is a very large amount of facts you're getting wrong here. I'm not surprised anymore that you misunderstand all the references you've linked to. -
NewYorkJ at 13:33 PM on 15 May 2009A broader view of sea level rise
Ron Cram, My critique is of the journal, not the person. Since the journal is not cited and the editor has admitted to following a political agenda, it renders the journal's credibility rather weak and thus the study highly dubious. You don't seem to be addressing the problems with E&E, but instead appear to be dodging on misplaced ad hominen charges. Material in that journal is as good as self-published material. If an E&E study is all you have, there isn't much to discuss. I was hoping for more. -
Quietman at 13:15 PM on 15 May 2009It's the sun
Patrick Re: "HOW does O2 cause cooling? Effects on the ozone layer? Interesting, but I need some numbers..." See: The rise of oxygen caused Earth's earliest ice age Thursday, May 7, 2009 "Geologists may have uncovered the answer to an age-old question - an ice-age-old question, that is. It appears that Earth's earliest ice ages may have been due to the rise of oxygen in Earth's atmosphere, which consumed atmospheric greenhouse gases and chilled the earth." -
Quietman at 12:09 PM on 15 May 2009Arctic sea ice melt - natural or man-made?
Patrick Re: "A trillion milligrams = a billion g = a million kg = a thousand metric tons" A lot for you, nothing to the Earth. Everything is relative. The surface is 70-75% water. Water controls the climate it just so many ways (but it's the sun that gives the oceans most of it's heat potential). Re: "I still don't know what you mean... " The science isn't settled. Re: "1. So what if the policy at one time ignores global warming risk? Once upon a time, there were few restrictions on smoking and ciggarette advertising - why would people not restrict an unhealthy product? Well, it is unhealthy, and (libertarian objections aside) now we have restrictions." Because it's not a pollutant, it's perfectly safe mixed into the air we breathe and required by plants, a part of nature's carbon cycle. We have known about GHGs and CO2 as a GHG for over 100 years so you don't seem to realize that real scientists know it's not a problem. Never has been and never will. It's O2 that can be a bugger. -
Ron Cram at 10:14 AM on 15 May 2009A broader view of sea level rise
Chris, I will have to brush up on CO2 through the centuries but I have a hard time swallowing a narrow range of CO2 variability. Consider the fact anthropogenic CO2 emissions has increased dramatically over the last two decades, yet the rate of accumulation in the atmosphere is about the same or even less. This shows the carbon cycle can have a hugely different natural uptake of CO2. 2. You write: "These rises {pre-1900 and pre-1950} in atmospheric CO2 are expected to make a significant contribution to the surface temperature changes during these periods." Not true. Also "the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively." Please! Have you ever heard the term "false precision?" The instruments available during this time cannot measure in hundredths of a degree. And 0.15C is not signficant, it is a hypothesis - an calculation. No one of the many pro-AGWers I have talked to think 9 ppm of CO2 is significant or even measurable. -
Philippe Chantreau at 09:24 AM on 15 May 2009A broader view of sea level rise
NewYorkJ, that would be her honesty. The editor is Sonja Boehmer-Christiansen. An extensive search of the litterature (22000 journals) by the folks at the DeSmog revealed 4 research articles by her on environmental policy. In the case of E&E her editing is used in lieu of conventional peer-review. Last I checked, E&E was not listed in Journal Citation Reports: http://thomsonreuters.com/products_services/scientific/Journal_Citation_Reports The issue of land use is not ignored at all by climate science and it is a significant contributor to CO2 production. There is a wealth of litterature on the subject, a few examples and summaries here: http://cdiac.ornl.gov/by_new/bysubjec.html#landuse sghwterttrrtrtt4r34r34trt34t5r34rt34tr34rt435rt43 -
Ron Cram at 09:01 AM on 15 May 2009A broader view of sea level rise
NewYorkJ, you obviously do not know what an ad hom argument is. An ad hom argument is when you go after the person rather than deal with the facts they raised. All you are doing is saying "Yeah, but it's true." It is completely irrelevant. What is relevant is the question of whether or not Loehle's paper is accurate. If it is accurate, it could be published by the Devil himself and it would still be accurate. Ad hom attacks do not impress me. And they should not impress you either. -
chris at 08:04 AM on 15 May 2009A broader view of sea level rise
Ron, I think we've established that oceans have likely continued to take up heat at least during the 5 year period to 2008. The scientific evidence supports that conclusion (see references [*] and [**] in my post #7 above). The magazine note by Loehle that you url hardly lends itself to a contrary conclusion, finishing as it does with:”While the current study takes advantage of a globally consistent data source, a 4.5-year period of ocean cooling is not unexpected in terms of natural fluctuations. The problem of instrumental drift and bias is quite complicated, however, (Domingues et al. 2008; Gouretski and Koltermann 2007; Wijffels et al. 2008; Willis et al. 2004, 2008a) and it remains possible that the result of the present analysis is an artifact.”
re #17/#20 Your assertions about the lack of contribution of land use changes to atmospheric CO2 levels, and the contribution of mid19th-mid20th century increases in atmospheric CO2 to temperature changes don't accord with the evidence: 1. Atmospheric CO2 levels are recorded in the Antarctic Law Dome cores going back 1000 years (see reference [***] in my post #9)...these have more recently been extended back 2000 years (see [*] below). These data allow insight into natural variability on the decadally-averaged timescale (since the CO2 data in these high resolution cores is averaged on that timescale). During the period from around 1100 to around 1570, for example, atmospheric CO2 levels were ~ 281 +/- 3 ppm. That gives an indication of the variation under relatively stable climatic conditions within a system in which carbon is cycled through the atmosphere/land and oceans. It's small, and especially so when yearly variation (El Nino years result in a slightly enanced [CO2], and vice versa for La Nina's, for example) are averaged out in the cores. Atmospheric CO2 levels dropped during the period of the LIA (275 ppm +/- 2 pm during the period 1600 to the middle of the 18th century). By 1800, CO2 levels were back to the pre-LIA levels of 283/284 ppm. In other words the carbon cycle had re-established its pre-LIA "equilibrium" by the early part of the 19th century. The rise in atmospheric CO2 levels from ~ 286 ppm - 297 ppm in the period 1850-1900, and from ~300 ppm to 309 ppm from 1910-1940, are very clearly outwith the natural variation seen in the preceding 800 years. They don't go up and down slowly over long periods (the fall in CO2 into the LIA was relatively fast), but go up and up rather quickly in the context of natural variation. They are very likely the result of anthropogenic emissions and land use changes. We could document the evidence for this, but perhaps this thread isn't the appropriate place. 2. These rises in atmospheric CO2 are expected to make a significant contribution to the surface temperature changes during these periods. It's very easy to calculate that within a climate sensitivity right in the centre of the likely range (3 oC of warming per doubling of atmospheric CO2), the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively. Since the total global warming from the mid 19th century to the mid 20th century was around 0.3-0.4 oC: http://www.cru.uea.ac.uk/cru/data/temperature/ the anthropogenic contribution from industrial and land use changes could rather easily account for the bulk of the warming during this period. So clearly it's NOT a "total fallacy to think a few PPMs of atmospheric CO2 in the last half of the 19th century is going to have a measurable impact on the atmosphere or ocean heat content or rising sea levels"! Within our understanding of the greenhouse effect, we certainly expect that these small but significant rises in atmospheric CO2 should cause the surface to warm, and the oceans to take up some excess heat and expand somewhat. [*] C. MacFarling Meure et al. (2006) Law Dome CO2, CH4 and N2O ice core records extended to 2000 years BP Geophys. Res. Lett. 33, L14810. -
Dan Pangburn at 05:23 AM on 15 May 2009It's the sun
As experienced during the Maunder Minimum, the observation that there are few sunspots is associated with cold (see e.g. Fig. 2 at http://scienceandpublicpolicy.org/images/stories/papers/scarewatch/really_cooling.pdf ). This indicates a connection between sunspot count and energy reaching earth’s surface. It is revealing to plot against time the integral of the sunspot data reduced by a factor times the fourth power of the average global absolute temperature. This results in a graph with amplitude proportional to energy change and therefore an expected influence on average global temperature change. Adjust the factor so that the first part of the curve is fairly level. This graph shows a substantial and continued energy gain starting in about 1945. This corroborates the observation of a Solar Grand Maximum that went on for about 70 years and appears to have ended a few years ago. Now, look at the graph of average global temperature such as the NOAA data available at ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/monthly.land_and_ocean.90S.90N.df_1901-2000mean.dat . Notice the approximate 30 year up-trends and down-trends that have been associated with the Pacific Decadal Oscillation (PDO). Note that from about 1945 until about 1975 the PDO down trend must have been a stronger forcing than the gain from sunspots since the temperature trend was down. After 1975 the PDO uptrend combines with the increased solar activity to produce the gain in average global temperature observed late in the 20th century. The sun has gone quiet and the PDO is in its downtrend. The PDO downtrend combined with the quiet sun is going to result in a continuation of the planet cooling trend. The sun has not been this quiet this long since 1913. Clouds are parameterized in the AOGCMs, are recognized as being very significant and are a recognized weakness in the analysis. Sunspot changes appear to be a catalyst for cloud changes and therefore have much greater influence than just Total Solar Irradiation. The Climate Science Community is, for the most part, unaware of the science (it’s not in their curriculum) that proves that added atmospheric carbon dioxide has no significant influence on average global temperature and therefore earth’s climate. See my pdf linked from http://climaterealists.com/index.php?tid=145&linkbox=true for the proof and to identify the missing science. Or email danpangburn@roadrunner.com
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