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Comments 34851 to 34900:

34851. MThompson at 23:30 PM on 7 August 2014
       2014 SkS Weekly News Roundup #31B
       

       Perhaps once again my commentary was unclear to some. In my original comment numbered 4, I was referring to the article “Intensifying ocean acidity from carbon emissions hitting Pacific shellfish industry,” and not to all the possibilities of extreme anthropogenic global climate change in general. The IPCC quote I provided stands in plain opposition to the headline of the referenced article, unless some dramatic new evidence has come to light since the final draft of the IPCC AR5.

       If I correctly understand Tom Curtis’ missives (5 & 6), I have left some readers with the impression that, since the IPCC reports that there are few examples of PH decrease beyond natural variability, my assertion is that marine life will not be harmed by increasing atmospheric CO2.

       Please forgive the pedantic, but the scientific method applied to this situation:

       
       1) It is observed that atmospheric CO2 levels are rising, and have been doing so for decades.
       2) It is observed that reduced PH is harmful to marine organisms, both in natural and laboratory settings.
       3) It is hypothesized that the increase in atmospheric CO2 will lead to decreased PH of the oceans, and that will in turn be harmful to marine life.

       
       Thus I restate:
       "Few field observations to date demonstrate biological responses attributable to anthropogenic ocean acidification, as in many places these responses are not yet outside their natural variability and may be influenced by confounding local or regional factors."
       IPCC AR5 WGII p.9

       Moderator Response:

       [Rob P] - That's a poorly-worded paragraph in the IPCC assessment. Not as bad as the Himalayan glacier error from the previous report, but the inference is that ocean acidification needs to be outside natural variability to cause problems for marine calcifiers - which is just silly.

       This is like suggesting that even though the Earth is warming, and causing heatwaves and droughts to intensify and occur more frequently, we can't attribute enhanced tree mortality in drought-affected regions to global warming, because the mean temperature has not moved outside natural variability.

       I suspect this has been watered down by the political process involved in signing off the reports. Watered down to such an extent that it is nonsensical. No matter, there's plenty of emerging research being published on ocean acidification, and we'll start to get a better idea of which species are likely to survive, and which will perish.  

       As for your assertion that marine life will not be affected by ocean acidification, it's a nice idea, but one not supported by the scientific literature, nor present-day observations. The dissolution of the shells of pteropods around Antarctica, and in the California Current System are a case in point.

       

       It certainly seems that corrosive seawater can be tolerated by many marine organisms, provided that the exposure is brief, but long-term exposure creates energy demands that simply cannot be met under normal conditions. In other words, as long as the calcifier can get sufficient food to power the calcification process, it can make up for the dissolution occurring outside the calcifying space. In the real world, this isn't going to happen over the long-term as the entire carbon chemistry of the ocean continues to change. Ocean acidification is like a rising tide in that it raises all boats i.e. the energetic demand increase right throughout the life-cycle.

34852. ozboy1 at 18:47 PM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       My thoughts these days go to implications. 3.3 mm is a global average and there are strong regional variations, or so I read. At that rate in 10 years its 3.3 cm and in 100 years .33 of a metre. In the end I wonder how much of an issue that is?

       This leads to another question of how much future sea level rise is locked in? If we magically reduced excess CO2 output tomorrow for how much longer would sea levels rise?

       My third question is that we have seen in recent years a slower rate of growth in surface air temperature (now about 5% higher than the 20th century mean)  and a slower rate of growth in sea level rise. El Nino is invoked as a partial explanation for both. Do we see a similar development in the rate of change in water acidity?

       Moderator Response:

       [Rob P] - No, El Nino does not explain the slower warming rate in surface air temperatures in the 21st century. Stronger and more frequent La Nina, however, are only a partial explanation - see Climate Models Show Remarkable Agreement with Recent Surface Warming for instance.

       La Nina is dominant during the negative phase of the Interdecadal Pacific Oscillation [IPO]. As the spin-up of the wind-driven ocean circulation is able to mix more heat down into the ocean (mainly the Western Pacific & the subtropical ocean gyres), and draws up more cool water from below the thermocline in the eastern tropical Pacific, we get this stronger ocean warming/weaker surface warming pattern.

       It so happens that the trade winds connected with the current negative IPO have been exceptionally intense, and have thus temporarily counteracted the strong greenhouse gas-forcing during this century. See England et al (2014).

       

           

34853. Mikemcc at 15:59 PM on 7 August 2014
       Scientists lambast The Australian for misleading article on deep ocean cooling
       

       Unfortunately it appears that is no legislation that holds newspapers to account to publish factually correct information beyond the various libel laws.  The worst culprits appear to be the Murdoch press (Scum, Austalian, Faux News, etc) closely followed by papers like the Daily Fail, the Telegraph does seem to have seen the light a bit recently in getting rid of the likes of Chistopher Booker.

34854. scaddenp at 12:37 PM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       Stardustoz - if you look to the right of this comment, you will see the heat widget. Currently heat gain is equivalent to more than 2 billion Hiroshima bombs since 1998  - so no - the heat release from bombs is insignificant compared to the extra solar trapped from GHG accumulations.

34855. Stardustoz at 11:59 AM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       First of all, I'd like to thank you all for the information you provide here on a daily basis.  Second, I'd like to say that I am in no way scientific or have a degree in the sciences.  However, I do have a very inquisitive mind, especially when it comes to the effects that human interactions has on the Earth.  The question I wish to pose in regards to sea level rise and warmth is whether the large scale nuclear testing that has been conducted at sea over the years has contributed and whether such anthropogenic factors are considered in the models.  Would this have a significant impact on sea level temps and rise?  Again, please forgive me if this question is a silly one to ask here.

34856. Bob Loblaw at 10:56 AM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       r.pauli:

       Yes, warmer air is capable of holding more moisture. The relationship is roughly exponential.

       

       At cold temperatures (say, -30C), the air holds little moisture and large changes in temperature don't change that capacity by much. You don't see much snow falling at cold temperatures, because there isn't much moisture and you can't get much out for a given decrease in temperature. 

       At warmer temperatures (say +30C), the capacity is much higher, and small changes in temperature make a much bigger difference. A little bit of cooling leads to significant condensation, which lleads to thick clouds and lots of potential for heavy rain.

34857. michael sweet at 10:37 AM on 7 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       The NSIDC discusses this error in their current sea ice report (scroll to the end).  They say their data was unaffected by the reported error.  The NSIDC seems to feel that it was a small error and that other data, including their own, confirm the amount of Antarctic sea ice.  Antarctic sea ice ahs increased over the past three years.  The quesiton is whether it is a long term gain or just a short term fluxuation.

34858. scaddenp at 10:28 AM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       The atmosphere isnt a very large reservoir. On the other hand, moving enough water from sea to land can indeed lower sea level as it did in 2011.

       See "The 2011 La Niña: So strong, the oceans fell"

34859. Falk at 09:12 AM on 7 August 2014
       Nigel Lawson suggests he's not a skeptic, proceeds to deny global warming
       

       Thank you Rodger @19 and Tom @ 20 for both your answers. I knew somebody would notice the 'roughly' in my doubling. I did it too but didn't know how to edit.

       I indeed did not notice that it was a stacked graph. Thanks for pointing it out. And it makes sense to take the earths whole surface into acount I just thought that 0.44 W felt too small (with 21e22 J instead 35e22 J even more so) and I didnt' know if it was a valid estimate.

       Tom Curtis @20: I really was thinking about the ~2 W/m^2 for anthropogenic causes. Thanks for the brief summary with the feedback effects that explains the difference in my head.  By the way step three was coming from the mislead thought about sun incidence on the earth projected area but as you pointed out the energy imbalance is mainly due to the insulating effect of greenhouse gases and not in combination with direct sun light passing through them. 

34860. r.pauli at 09:00 AM on 7 August 2014
       A Relentless Rise in Global Sea Level
       

       I thought warmer air holds more moisture.   Wouldn't increased atmospheric heating carry water vapor sufficient to affect sea level?   

       If we have deluge rainstorms that can release many inches of water, wouldn't there be some quatifyable increase of water removed from oceans??

       Moderator Response:

       [Rob P] - The caption in Figure 2 does mention that the comparatively small increase in atmospheric water vapour is included in the calculations of Cazenave et al (2014). So this effect, albeit small so far, is accounted for.

       As for your 2nd question, yes, that certainly seems likely and is something I've mentioned in previous posts - these fluctuations could increase in magnitude as the Earth grows warmer. The atmosphere, in the absence of changes in the large-scale circulations, should be able remove and dump more water on land during La Nina-dominant (negative Interdecadal Pacific Oscillation) periods, and during La Nina events themselves.

       In the last 4-5 years the magnitude of the year-to-year variation in global sea level seems to have gone up quite a few notches - which suggests that the large-scale circulations are playing role as well.  

34861. longjohn119 at 06:12 AM on 7 August 2014
       Harvard historian: strategy of climate science denial groups 'extremely successful'
       

       These same Paid Politcal Propagandists were also involved in the denial of Acid Rain and it's causes (like mercury and CO2 it was from burning coal) as well as denial of the Ozone Hole and CFC's contributions to it.

34862. BojanD at 04:54 AM on 7 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       As for the mainstream result, I was of course refering to the 'corrected' data sets, so the word 'still' was indeed unfortunate. It's tough to get to probabilities, but I can do this.
       
       In favour:

       • other researchers obtained similar results
       • (minor due to overlap) algorithm was already compared to another one with negative results

       not in favour:

       • (minor since models don't work well for Arctic sea ice, too) models predicted the trend, but not as steep
       • the change to algorithm was made and reverted inadvertantly, which is kind of weird, and was not detected by other researchers. So this kind of weakens the first bullet.

       
       IMO it's likely (more than 68%) that current mainstream results reflect the real trend or that the error, if found, will turn to be a minor one.

34863. Paul D at 04:44 AM on 7 August 2014
       Scientists lambast The Australian for misleading article on deep ocean cooling
       

       It does seem that many newspapers today are willing to lie and fabricate 'truths' to further a political agenda when it comes to climate change.

       Lets not forget that national newspapers are not interested in pure news, they all have an agenda, every inch of page space has a 'meaning' and a message even when an opposing view to the papers ideology is expressed. The problem is at the top and the agenda of the editor and owners.

       In the context of democracy and politics this probably works to the advantage of our communities. But when it comes to facts and science, it clearly fails us all.

34864. Donny at 03:40 AM on 7 August 2014
       2014 SkS Weekly News Roundup #30A
       

       It is an incredulous stretch to link rain storms (which may not even be related to global warming let alone man's influence on the warming) to Chicago's lack of maintaining it's own infrastructure.   Maybe someone should suggest spending tax dollars on things that matter. ... like controlling ecoli.

       Moderator Response:

       [Rob P] - The increase in heavy downpours in a warming world has long been expected based on the Clausius-Clapeyron relation, i.e. a warmer atmosphere can hold more moisture and thus when it rains, bursts of rain tend to be heavier.

       As the article points out there has been a 20% increase in these heavy downpours in the midwest USA. But this is, obviously, a global phenomenon - see Westra et al (2013) - Global Increasing Trends in Annual Maximum Daily Precipitation, who write:

       "Furthermore, there is a statistically significant association with globally averaged near-surface temperature, with the median intensity of extreme precipitation changing in proportion with changes in global mean temperature at a rate of between 5.9% and 7.7% K−1, depending on the method of analysis. This ratio was robust irrespective of record length or time period considered and was not strongly biased by the uneven global coverage of precipitation data."

       SkS will have a rebuttal to your myth (which is not uncommon) in the near-future.

34865. Tom Curtis at 03:27 AM on 7 August 2014
       Nigel Lawson suggests he's not a skeptic, proceeds to deny global warming
       

       Falk @18, the Earth's surface area is the area of an oblate spheroid.  The area of a disc of the same diameter as the Earth's equatorial diameter is 1.27 x 10^14, ie, approx 1/4 of the Earth's surface area.  Therefore your step three, which attempts to compensate for the difference between a circular and a spherical surface is double counting.

       I am unsure as to the point of your step two.  Most of the change in the energy balance is due to increased greenhouse effect reducing outward radiation, and an increase in temperature increasing outward radiation.  Both of these effects occur approximately equally over the whole globe, so there is no need to determine the hypothetical case where it occurs only on one side of the globe.

       I assume you are trying to reconcile the global energy imbalance (average of 0.44 W/m^2 over the last fifty years) with the change in forcing due to anthropogenic causes (around four times that).  The difference is because the change in forcing is the calculated effect of change atmospheric compostion (primarilly) since 1750 on the assumption that there are no temperature changes at the Earth's surface.  In fact there have been temperature changes, which have increased outgoing radiation.  Therefore the expected energy balance is Forcing minus λ temperature change, where lambda is a linear factor representing the effects of feedbacks.  That is calculated to be around 0.5-1 W/m^2, and calculated values lie comfortably within the error margins of observed values.

34866. MA Rodger at 03:13 AM on 7 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       ☺ On what do you base your view that it is a “fact that (the) mainstream result is probably still correct”? Note that the implication of using the word “still” suggests it has remained correct. Also what levels of probability do you consider to be factual (as to not place some bound on it would make the statement meaningless)?

       ☻ I also note that you seem to be presuming that I am signed up to the error (which I think we can agree exists) as having been fixed. On what do you base such a presumption?

       You'll likely agree it best to clear this matter up before becoming embroiled in the explanation of an actual enigma with all that that may entail.

34867. MA Rodger at 03:04 AM on 7 August 2014
       Nigel Lawson suggests he's not a skeptic, proceeds to deny global warming
       

       Falk @18.

       Two point for you.

       No 3 is not "roughly another doubling" but exactly a doubling. The area of a sphere is 4πr² and the area of a disc is the well-known πr².

       Your initial 35e22J estimate appears to be based on a misinterpretation of the graph and thus too high. It is a "stacked" graph, thus the sum of each element can be directly read from the graph. So about 21e22J would be nearer the mark. In my book, the graph is a bit on the schematic side as Ocean Heat Content fell 1960-70 if you plot out the usual Levitus 0-2000m data.

34868. ubrew12 at 02:19 AM on 7 August 2014
       Scientists lambast The Australian for misleading article on deep ocean cooling
       

       "The article by Graham Lloyd will likely leave a mis-impression"

       What's with the kid-gloves?  How hard is it to say Lloyd lied?  His first sentence makes two claims neither of which is true.  How likely is this unintentional?  His paper should be sued and he should be fired.  Until this happens, this 'Pied Pipering' of society will lead to its ruination.  At this point, what he's doing is criminal.

       (-snip-) People like Lloyd are actually encouraged by the meekness with which society responds to their outright fabrications on behalf of their power structure.  Make an example of him and his publisher that truth matters, or they will happily whistle our children to the cliff and bid them jump, and see in that their own obvious superiority.

       Moderator Response:

       [JH] Offensive personal opinion deleted. 

34869. Falk at 23:57 PM on 6 August 2014
       Nigel Lawson suggests he's not a skeptic, proceeds to deny global warming
       

       Hi everyone!

       I am not a climate scientist but have been interested on a personal level in the the research going on for some time now. I like reading (and have been for a while) the discussions on this site even though I sometimes get annoyed by the sceptics/alarmist fights.

       Anyway I finally registered because everytime I see the figure posted in this blog post above I ask myself if one of the following estimates is somewhere near the 'real' thing :)

       If I sum up the total energy accumulated in all three regions I get something like a 35e22 J (or W*s) increase over 50 years (1960-2010). If I just devide this by the time of 1.577e9 s (50y in seconds) and by:

       1. the earths total surface of 5.1e14 m^2 I get a net power per squaremeter of 0.44 W/m^2 that is needed over 50 years to deposit the heat.

       2. half the earths surface as only one half is hit by the sun at a given time. It gives double the power per squaremeter nedded with 0.87 W/m^2

       3. the projected area of the earth (aka circle of earths radius) with an area of 1.27e14 m^2 which is roughly another doubling to 1.75 W/m^2

       If someone could just give me a quick response if this is complete nonesense or if one of them is a useful estimate I would appreciate it a lot. Thank you!

34870. Mick9422 at 18:07 PM on 6 August 2014
       A Relentless Rise in Global Sea Level
       

       So many arguments for and against.

       I have concerns, mainly due to the excessive amount of carbon now in the atmosphere compared to past low levels.

       But then again, am I worried over nothing, and the Earths systems can cope with these levels, and all will be well.

       Who knows !!

       One end of the argument is depicted by this cartoon . . . . .

       http://cartoonmick.wordpress.com/editorial-political/#jp-carousel-891

       Cheers

       Mick

       Moderator Response:

       [JH] Activated link.

34871. Tom Curtis at 16:34 PM on 6 August 2014
       Postma disproved the greenhouse effect
       

       Thankyou Glenn.  Much appreciated.  I am somewhat loathe to pay twice for the same paper as you can imagine.

34872. PhilippeChantreau at 13:03 PM on 6 August 2014
       Harvard historian: strategy of climate science denial groups 'extremely successful'
       

       Matt, you'll find of plenty of returns by trying "NIPCC" (not NICPP). This organization is well known of SkS contributors, as is the grotesque parody of information with which they have tried to infect the public place.

34873. wili at 12:01 PM on 6 August 2014
       A Relentless Rise in Global Sea Level
       

       Good presentation. But isn't the larger point that 20 years is not long enough to accurately chart anything? It's nice to be able to be able to identify some of the factors that go into natural variation here. But really, 20 years?

       Isn't it true that if you take a slightly longer time frame (and anything longer that 20 years would surely be more appropriate), that there has actually been an acceleration in the rate of global warming? 1990 or so actually seems to be something of an inflection point, with the rate twenty years before it being about half that of the rate over the following twenty years or so.

       LINK

       Moderator Response:

       [PS] Fixed link.
       The length of time required to draw inference about a trend depends on the amount of noise (variability) compared to magnitude of trend. 20 years is short for surface temperature but long for sea level.

       [RH] Shortened link.

34874. Glenn Tamblyn at 10:18 AM on 6 August 2014
       Postma disproved the greenhouse effect
       

       Tom

       I have a copy of Conrath. If you want I can email you a copy

34875. Tom Curtis at 08:09 AM on 6 August 2014
       2014 SkS Weekly News Roundup #31B
       

       Sorry, I picked up the wrong original quote.  Here is the proper one:

       " Few field observations to date demonstrate biological responses attributable to anthropogenic ocean acidification, as in many places these responses are not yet outside their natural variability and may be influenced by confounding local or regional factors. See also Box TS.7. Natural climate change at rates slower than current anthropogenic change has led to significant ecosystem shifts, including species emergences and extinctions, in the past millions of years."

       (Bolded elided by M Thompson)

       Also relevant are the two following from the Executive Summary of Chapter 6:

       "Rising atmospheric CO2 over the last century and into the future not only causes ocean warming but also changes carbonate chemistry in a process termed ocean acidification (WGI, Chs. 3.8.2, 6.4.4). Impacts of ocean acidification range from changes in organismal physiology and behavior to population dynamics (medium to high confidence) and will affect marine ecosystems for centuries if emissions continue (high confidence). Laboratory and field experiments as well as field observations show a wide range of sensitivities and responses within and across organism phyla (high confidence). Most plants and microalgae respond positively to
       elevated CO2 levels by increasing photosynthesis and growth (high confidence). Within other organism groups, vulnerability decreases with increasing capacity to compensate for elevated internal CO2 concentration and falling pH (low to medium confidence). Among vulnerable groups sustaining fisheries, highly calcified corals, mollusks and echinoderms, are more sensitive than crustaceans (high confidence) and fishes (low confidence). Trans-generational or evolutionary adaptation has been shown in some species, reducing impacts of projected scenarios (low to medium confidence). Limits to adaptive capacity exist but remain largely unexplored. [6.3.2, CC-OA]

       
       Few field observations conducted in the last decade demonstrate biotic responses attributable to anthropogenic ocean acidification, as in many places these responses are not yet outside their natural variability and may be influenced by confounding local or regional factors. Shell thinning in planktonic foraminifera and in Southern Ocean pteropoda has been attributed fully or in part to acidification trends (medium to high confidence). Coastward shifts in upwelling CO2-rich waters of the Northeast-Pacific cause larval oyster fatalities in aquacultures (high confidence) or shifts from mussels to fleshy algae and barnacles (medium confidence), providing an early perspective on future effects of ocean acidification. This supports insight from volcanic CO2 seeps as natural analogues that macrophytes (seaweeds and seagrasses) will outcompete calcifying organisms. During the next decades ecosystems, including cold- and warm-water coral communities, are at increasing risk of being negatively affected by ocean acidification (OA), especially as OA will be combined with rising temperature extremes (medium to high confidence, respectively). [6.1.2, 6.3.2, 6.3.5]"

       My summary of the preceding post remains fair comment.

34876. MattJ at 08:07 AM on 6 August 2014
       Harvard historian: strategy of climate science denial groups 'extremely successful'
       

       Yes, the disinformation campaign has been successful — if you call 'success' winning a policy determined to make the lives of your few generations of descendants absolute misery.

       But it is about to get worse: I just saw an announcement on Quora of an even more shameful, bold fraud: the mysteriously and suspiciously named "NICPP", a new front group for The Heartland Institute, claiming scientific backing for many of the false criticisms of the ICPP that we have all heard before.

       I also noticed that nothing comes up in the search here at Skeptical Science when I input "NICPP" or "nicpp". That ought to change pronto.

34877. Tom Curtis at 07:58 AM on 6 August 2014
       2014 SkS Weekly News Roundup #31B
       

       Speaking of sticking to what is known, how about we start by quoting in context:

       "A few studies provide limited evidence for adaptation in phytoplankton and mollusks. However, mass extinctions in Earth history occurred during much slower rates of change in ocean acidification, combined with other drivers, suggesting that evolutionary rates may be too slow for sensitive and long-lived species to adapt to the projected rates of future change (medium confidence)."

       (Bolded sections elided by M Thompson)

       Also from the summary on Ocean Acidification:

       "Ocean acidification poses risks to ecosystems, especially polar ecosystems and coral reefs, associated with impacts on the physiology, behavior, and population dynamics of individual species (medium to high confidence). See Box TS.7. Highly calcified mollusks, echinoderms, and reef-building corals are more sensitive than crustaceans (high confidence) and fishes (low confidence), with potential consequences for fisheries and livelihoods (Figure TS.8B). Ocean acidification occurs in combination with other environmental changes, both globally (e.g., warming, decreasing oxygen levels) and locally (e.g., pollution, eutrophication) (high confidence).  Simultaneous environmental drivers, such as warming and ocean acidification, can lead to interactive, complex, and amplified impacts for species."

       (Bold in original)

       So, to "stick with what is known" in M Thompson's version, you need to quote out of context, and ignore the IPCC's findings.  That is not what I would call integrity.

34878. Jutland at 07:55 AM on 6 August 2014
       Postma disproved the greenhouse effect
       Tom @85: that is a very, very helpful answer, thank you. The confusion was my own, not in any discussion with anyone else. I have been wondering where I might have got definition (2) from, and now think that I may have misinterpreted statements in texts online or in books, eg a statement like "IR photons escape the atmosphere at the tropopause" might have been misinterpreted in my mind as "the tropopause is the height at which IR photons escape." Oh well. On the other hand, I am feeling a bit chuffed (especially as a non-scientist) that I worked out that different frequency IR photons must escape the atmosphere at different altitudes.
34879. MThompson at 07:19 AM on 6 August 2014
       2014 SkS Weekly News Roundup #31B
       

       Well said, DavidBird at comment #3. To maintain integrity we have to stick to what is known:

       "Few field observations to date demonstrate biological responses attributable to anthropogenic ocean acidification, as in many places these responses are not yet outside their natural variability and may be influenced by confounding local or regional factors."

       IPCC AR5 WG11 p.9 

34880. Tom Curtis at 05:28 AM on 6 August 2014
       Postma disproved the greenhouse effect
       

       Jutland @84:

       1)  The tropopause is that level of the atmosphere between the troposphere and the stratosphere were the negative change of temperature with altitude falls to zero.  That also happens to be were radiation can transfer energy more rapidly than convection.  As on some planets there is no stratosphere, that fact is often used as the definition (ie, your definition (1)) of the troposphere (as it is more general).

       2)  I have never seen your definition (2) used as a definition as the tropopause.  The average level from which radiant energy escapes to space is called the "skin layer", or "the effective  altitude of radiation to space".  It does not coincide with the tropopause.  On average over the globe, it is at 5 km altitude, compared to the 10 km altitude of the tropopause.

       It is possible you, or somebody with whom you are having a discussion, or reading, has confused the definition of the "skin layer" with the definition of the Top Of Atmosphere (TOA).  For convenience of calculation, radiative forcing is defined relative to what is called the TOA, but is really the tropopause.  That is the level at which the net radiative flux is calculated in determining the radiative forcing for various substances, but is not the level from which most radiation comes.  Note that for observational data sets, the TOA usually refers to the altitude of the satellites on which the instruments are mounted, or 70 Km (which ever is higher).

       3)  Finally, yes, the average altitude of effective radiation to space differs for different chemical compounds, and for different wave numbers (a unit of frequency).  This can be illustrated by this diagram from Conrath et al (1970), showing model calculated and observed upward IR radiation at the TOA (ie, the altitude of the satellite):

       

       The black body temperature curves for various temperatures are shown on the graph.  Where they intersect the upward IR spectrum, radiation at that wave number has an average temperature equal to the temperature of the black body curve.  If we then know the surface temperature and the lapse rate, we can then calculate the average altitude of radiation for that wave number.  Unfortunately I have lost my copy of Conrath et al due to a faulty hard drive, so I do not know the correct values.  However, the flat trough at the bottom of the CO2 absorption band (approx 600 - 700 cm^-1) represents the tropopause, while the the small spike in the center at approx 666 cm^-1 is the region of peak absorption by CO2, and has an average altitude of radition in the stratosphere (hence the higher temperatures).

       The average altitude of radiation for water vapour and methane are much lower, being around 3 km as can be seen in this full spectrum reproduced by Science of Doom (via Goody 1989):

       

       I hope that helps.

34881. Jutland at 03:57 AM on 6 August 2014
       Postma disproved the greenhouse effect
       I'm hoping I can check some terminology here. I've heard the term tropopause being applied to at least two different things: (1) the level at which convection ceases to be the main heat transfer process in the atmosphere, and (2) the level at which IR photons escape into space. But they're not necessarily the same thing? - it occurs to me that IR photons trapped by CO2 might escape at a different height from IR photons trapped by say methane. So in definition (2) it should be possible to have different tropopauses for different GHGs. But under definition (1) there's only one tropopause. Am wondering which actually is the tropopause (or whether I have got hold of the wrong end of the stick completely).
34882. BojanD at 03:26 AM on 6 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       Ok, I see the source of our misunderstanding. You were focusing on the scientific process per se (the fact that error was undetected and even that the fix was undetected, too), I was focusing on the fact that mainstream result is probably still correct, hence my remark about error being real or not. Now I'm not saying that your position is not important. :)
       
       However, now I'm faced with another enigma. If Comiso made an error and the fix inadvertantly, how come the other researchers didn't detect any of this stuff before if they were using independant methods. Surely they didn't independantly made an error and the fix at the same time. Or is the data really that noisy?

34883. WRyan at 01:37 AM on 6 August 2014
       A Relentless Rise in Global Sea Level
       

       It's interesting that you comment that the rapid rise in ocean heat content during the period 2001-2004/5 is unexplained. I think that Hansen et al.

       J. Hansen et al.: Earth’s energy imbalance and implications (p.13439)

       attributed at least some of the rise to a bounce back from the preceding period (1991-2000) where ocean heat content fell.

       In the paper, the mechanism for this heating was described as:

       "The physical origin of the rebound is simple. Solar heating of Earth returns to its pre-volcano level as aerosols exit the stratosphere. However, thermal emission to space [from the ocean's surface] is reduced for a longer period because the ocean was cooled by the volcanic aerosols."

       Is that hypothesis valid? What are the alternate explanations?  

       Moderator Response:

       [Rob P] - As far as explanations go, it's not really much of an explanation. The Mt Pinatubo eruption would certainly have played a role, but a whole lot more detail is needed to qualify as a possible explanation.

34884. John Michael Carter at 01:31 AM on 6 August 2014
       Harvard historian: strategy of climate science denial groups 'extremely successful'
       

       "But the overall picture continues: these groups continue to dismiss or disparage the science, attack scientists, and sow doubt."

       Interesting about Johnson, I wondered why this wasn't obvious a long time ago (and now see that it was.) I've also been arguing for almost two decades that the basics of climate change are pretty much the same (and not dependent on shorter term patterns. (Since then we've had 14 of the 14 warmest years on record according to the composite data of the three major global data sets as compiled by the World Meteorological Organization, but all anybody can talk about is the misleading pause. And focus far too much on air temperature, and not ocean temperatures.) 

       Anyway, Oreskes is spot on.

       I think the difference is they come to believe it (much as a laywer advocating for a client often genuinely takes on that perspective) and many want to believe it for various reasons, laid out here, and it creates a kind of powerful self reinforcing effect - particularly on the internet where self selection leads to excessive insular reinforcement. It has almost become a religion, but climate change refuters see it as the opposite of course, and project that outward.

       There's a constant pattern that simply builds on and reinforces the idea that climate scientists are unscientifically engaging in a narrow, research grant funded groupthink expedition, and the clueless koolaid drinkers are following, while the intreped skeptic/refuter is bold enough to discover and know the true facts and objectively and cooly evaluate and assess the issue. -All while going nearly nuts over any sort of disagreement that makes a good point, or finding some way to simply dismiss it or not consider it, and often wildly disparagingly at the same time.  Even skeptical science, over at WUWT, has no merit according to them. Because it has to have no merit. If it had merit, then the extremeness of their views would start to seem unreasonable. So only those facts and ideas that reinforce or support those views are considered real, all others have been and are by one measure or another dismissed, not considered, or disregarded, or, simply, changed. By looking at it differently. (Such as with oceans, since, well we can't have measured every square inch, so once we measure the "right" things, it is no longer warming.)

34885. MA Rodger at 22:19 PM on 5 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       BojanD @14.

       Digging out the meat from accounts of this Comiso/Eisenman dispute did have a feel of obscure histiography about it. And the descriptive requirements are quite high for this subject, so slips easily occur. The Live Science account, for instance, presents a sentence that goes way beyond where it should, saying - "According to this view, the trend toward expansion might be an error introduced by a recalibration of how satellite data is processed."

       Note that, contrary to your assertion @14, there is no dispute that the error is real. The dispute concerns the potential location of it within the latest algorithms.

       My entire point with the "misinformation" comment is that it is a very strong accusation to make against the Eisenman et al paper. And the only support provided for such a strong accusation (Essentially My work is correct because it yields the same result as the work of others unaffected by this dispute [a point you make @14], and anyway it's water under the bridge now the trend has increased.) is not a scientific defence. Thus the accusation is wholly unwarranted and that does need some explanation. Thus I consider that the harsh words could result from a level of animosity existing already between the two of them.

       Elsewhere the paper has been described as “an excellent piece of scientific vigilance" and note that account also makes plain that Comiso's calibration error was "inadvertantly introduced" and "corrected ... unknowingly" and the presence of an error only identified by dint of Eisenman et al.

       And concerning the water-under-the-bridge dismissal of EIsenman et al (2014), the effect of this undocumented error/correction, while diminishing as new data accumulates, remains still quite large and would have constituted the majority of the trend had not there been a genuine increase in trend to mask it - and note it is a 'masking process' that has grown a lot since the paper was written.

34886. JRP at 18:05 PM on 5 August 2014
       A rough guide to the components of Earth's Climate System
       

       Does anybody know the residence time of CO2 in the mesosphere?

       Are there any models that can used to simulate the CO2 exchanges between different layers in the atmosphere, please?

       Please reply to jrp@plen.ku.dk (IPCC CLA WG2). Best wishes. John R Porter

34887. factotum at 11:18 AM on 5 August 2014
       There is no consensus
       

       Given an organism in an environment one can state that the most adaptive will, by definition, be the most likely to survive. In order to adapt to an environment, an organism must understand it. One could say that the ability to understand ones environment is perhaps the best measure of intelligence that exists. As far as evolution is concerned it is the only measure that counts. Being able to do math and calculate a trajectory does not count, but being able to dodge a predator definitely does count. If two organisms share about the same abilities to react to a given situation then the organism that can read the situation the most accurately is the one most likely to survive.

       Now consider Global warming. A search of the internet will quickly demonstrate that the vast majority of species on the planet are moving to the poles, or are moving, if they can, to higher elevations. In addition to that, the timing of migration patterns are changing. If this data is not accurate then not only are all climate scientists part of this climate gate conspiracy, but so are all botanists, ethologists, marine biologists, and microbiologists, entomologists and probably some others. So there is the first bit of information: If you do not believe that the climate is warming on a global scale then in terms of evolution you are less knowledgeable about your environment (less intelligent) then the great majority of animals, plants, insects, and even ocean dwelling single celled organisms like plankton. Yep, you are dumber than a plant or an insect.
       http://news.discovery.com/earth/global-warming/animals-migrating-north-global-warming-110818.htm

       The pattern of GW denial sort of follows that of, and is similar to the arguments used to deny the correlation between smoking and cancer and a host of other diseases. You had actual scientists looking at the best available evidence on one side, and then you had paid charlatans with degrees in science working for corporations whose interests were threatened on the other. That was not 100% mind you, but it was pretty much how the advocates of the two positions lined up. A prime example is Dr. Frederick Seitz who sold out to become a spokesman for big tobacco and tried to convince people that tobacco was harmless. Later, after, at least according to many who were close to him, he became senile, he sold out to climate deniers.

       Now in this case on one side we have not only actual scientists doing their best to explain available information in light of best understood implications of thermodynamics, quantum mechanics, black body radiation etc. but you have almost all other life forms on the planet. By other forms of life, I mean almost every entity on the planet living in all but the most except extreme areas.

       Now if we accept GW, the next question is: what causes it? Trust me, it is not the sun which for the past 50 years has remained fairly constant or produced less radiation over that time while temperatures have risen. It has not changed much in the past 2000 years. Neither has known cosmic ray counts. This leaves galactic unicorn farts and CO2. We know about CO2, and how it would work, and the most likely results. We have no evidence of unicorn farts, but we do know about bloviation sources from hot air producers.

       Another red herring from AGW people are the failure of computer models and the testability of theories. If the prediction of a theory fails then the theory is false. Well folks, then I guess that the germ theory of disease is false. Clearly, many people exposed to "so called germs" never get sick. On the other hand people get sick who have never been exposed to these "so called germs" But wait, they are not really germs, they are viruses. See -— those scientists keep changing their story. Because they are in the pay of big pharma who just want to sell us drugs to make us sick so that they can make us more sick. And space that is another hoax. You know that the sun goes around the earth, just go outside and look for yourself. What? You believe the so called scientists?

       And speaking of hot air producers. This is a standard equation in statistics, the Gaussian integral. http://en.wikipedia.org/wiki/Gaussian_integral. If you can not follow the proof, then you do not have a basic understanding of one of the most basic equations in statistics, which means that you do not understand statistics, which means that you are as competent to argue a point of view on AGW as you are to advocate competing forms of cancer treatment without ever having had a course in biology.

       But since AGW deniers acutely suffer from Dunning-Kruger effect: http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect, they will continue to bloviate.

34888. BojanD at 01:12 AM on 5 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       @MA Rodger, it was exactly this 'misinformation' part that tilted me slightly into "not in favour of Eisenman" perspective.

       
       Even if this 'misinformation' is highly subjective, specially if there is a history between these two researcher, which I was not aware of, there is a case to be made against Eisenman: different methods yielded similar results, at least according to the Comiso (unless they all use his algorithm). Don't we usualy tell deniers that hockey stick is a pattern obtained by different methods and proxies and that it is therefore robust? When Eisenman identifies and provides objective criteria to check whether this error is real, we can definitely have further discussion. But we can all probably agree that even if nothing turns out, Antarctic sea ice is not that terribly important for the whole picture of AGW.

34889. chriskoz at 20:53 PM on 4 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       Tom@11

       You mistakingly linked to Abram 2013 on you local Windows machine (file:///C:/Users/Tom/Downloads). The weblink to it is vailable here.

34890. longjohn119 at 15:56 PM on 4 August 2014
       State Department cuts through the acid political environment on oceans and climate
       

       Key words here are :Evolved over 1/2 billion years

       They evolved and were able to evolve during climate changes over very long periods of time. Climate change like we are seeing today used to take thousands s to 10's of thousands of years allowing many forms of life to evolve with the change. Currently that same change in climate is taking place in a highly compressed 100 year timeline and nothing can evolve that fast with the exception of a few viruses and bacteria ....
       
       

       The speed of climate change effects lifeforms as much or more than the amount of total change.

34891. Stephen Baines at 13:39 PM on 4 August 2014
       State Department cuts through the acid political environment on oceans and climate
       

       Tom C @23

       Re nets and fish

       I'm pretty sure that Duarte, in those articles to which Jim and you link, is talking about lanternfish, mostly, as they are the highly sensitive small bioluminescent zooplanktivorous fish which make up much of the biomass in the mesopelagic.  They aren't caught in typical purse seines or trawls typical of commercial fisheries, and are too small for long -lines.  So they aren't of interest commercially.  

       They can be caught sometimes in zooplankton nets  with 0.2 - 1mm mesh that are drawn on frames a couple meters square or smaller through the water.  Such nets are mostly used by scientists and produce a pretty large pressure wave in front of them that sensitive mobile species can sense and avoid.  Plus, they are dragged behind a boat which also scares mobile organisms ahead of the net.   the point of the article Jim links to is that these nets to a bad job of catching them, which I believe.

       I will say that it is a little strange to say the ocean is "healthier" than you thought previously simply because you found a lot of biomass that you didn't know was there before, as he appears to in the article you link to.  The very point of the research is that we don't know how the status of mesopelagic fish has changed...or even what such a change would mean...since we know so little about it.  

       I guess his idea is that biomass is biomass and that a large biomass of fish that hasn't been harvested means less biomass lost to fishing.  But that will be little solace to fisherman with empty purse seines and long lines, not to mention consumers paying lots for fish!  It's kind of akin to those who point to life prospering in warm acidic oceans of the past, ignoring the fact that the life that prospered then was basically bacteria and of little relevance to our future in the face of climate change.

       Then again, I see that the article quoting him characterizes a Mola mola (ocean sunfish) as a mesopelagic fish, which is crazy, so maybe they misunderstood him!

34892. Stephen Baines at 12:55 PM on 4 August 2014
       State Department cuts through the acid political environment on oceans and climate
       

       Jim @24

       Re optimism...

       There is no need to protect Carlos Duarte...he is out in public for a reason.

       Part of Carlos's "optimism" regarding CO₂ may come from the fact that he is, at heart, a seagrass ecologist.  Seagrasses have been shown to increase photosynthesis in response to increasing CO₂, presumably because they are more strongly limited by diffusion of CO₂ than other nutrients and light.  Carlos has coauthored papers on the role of seagrass beds as carbon sinks, and has suggested using them in CO₂ remediation.  Seagrass beds can experience wide ranges in pH and CO2on even a daily cycle, not to mention over seasonal scales.

       He's also orginally a strict empiricist from the McGill school who places his faith on hard data, statistical analyses and successful prediction, and who reflexively questions claims he feels have an emotional basis.  This is a very admirable quality. However, one can make the case that this strict empiricism — the need to see a significant effect before admitting a phenomenon is possible —  may  be a little blind to anticipating problems.  In statistical parlance, it makes you subject to Type I errors.

       In the larger picture, though, I think that Duarte is really trying to counteract despair and the paralysis it produces.  Some people feel strongly about the ocean as an untouched frontier. These people often find it hard to accept that there really is no place on earth that has not been affected by humans.  The extent of our influence can lead them to despair of hope.  Carlos hopes to counteract this by grounding the discussion so people can reframe how they think about the ocean and try to make realistic, focussed choices, rather than simply rending their hair and calling names, which of course only alienates others.

       I agree with him in that I would not decribe the ocean as "broken" or "dead," terms I sometimes hear in the public discourse and in the classroom.  Those terms are too broad and emotional, and they don't suggest a way forward, only a way to feel. Knowing him, though, I'm also pretty sure he would not say the ocean is in great shape and that there is no chance it will get substantially worse. It definitely could (and has) in the absence of proper management. (Luckily...good management has often resulted in good results!) In that light I'd describe him as a "climate change optimist" only in comparison to those that despair — but that is a pretty low bar.

       Where he is undoubtedly an optimist is that he also thinks  we can repair/avoid problems in the ocean and maintain our standard of living IF we take the right actions, but those actions must be grounded in a real appreciation how the ocean behaves, not in ideals about how it should be, separate from humans.  He also is optimistic that communication of scientific findings can be done well and in a way that influences peoples actions.

       Really, that describes the kind of optimism that everybody on  this board displays if you think about it.   At this point, it's an attitude of necessity.

34893. Tom Curtis at 11:55 AM on 4 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       I should note that the updated figure to the one I show above does not include the correction discussed in the OP, and so may overstate the current sea ice extent relative to periods prior to 1994.  As such, it may not actually be a record even for the satellite era - but that is rather irrelevant given a fuller record.

34894. Tom Curtis at 11:52 AM on 4 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       jenna @9, the Antarctic sea ice extent has reached a record level for the period 1979-2014.  That is often, and incorrectly described as the satellite era.  In fact, satellite observations of antarctic sea ice began in 1973, although due to change of instruments and methods, NASA does not show the pre-1979 record alongside the later record.  There are further records going back to earlier in the 20th century from whaling records, and also from ice proxies such as the one shown below:

       

       (Source)

       The ice core proxy is from a compound released by algae that grow one the underside of the sea ice, and therefore represent a good proxy for sea ice extent, in this case extending back to 1841.  The red line is the satellite record from 1973-1994.  The sea ice extent has now exceeded the value in the early 1980s, thus representing a record over the satellite era.  It does not represent a record over the period since 1841.  Indeed, it does not even come close.

       A very informative report on antarctic sea ice, including an update of the above graph (6:37 on the video) has recently become available from the ABC.  A review of ice core proxies of sea ice extent is also available, and shows relative antarctic sea ice extent for the Holocene (fig 3) and the last 800,000 years (fig 5).

34895. DavidBird at 09:15 AM on 4 August 2014
       2014 SkS Weekly News Roundup #31B
       

       That article on increasing ocean acidification hitting the Pacific shellfish industry is pure nonsense and doesn't belong on this serious site. Atmospheric CO2 buildup has decreased ocean pH by less than 0.1 pH unit. That is harmless to shellfish at any life stage. There are much greater pH changes among seasons and perhaps during the diurnal cycle. Don't provide ammunition to the deniers by letting false alarms muddy the waters.

       Moderator Response:

       [PS] Please see further discussion here.

       [Rob P] - Corrosive seawater has indeed proven to be lethal to 'farmed' oyster larvae off the coast of Oregon in the USA. Oyster farmers were able to stem the loss of larvae by monitoring the acidity of ocean water drawn into the hatcheries - avoiding times when water was naturally highly corrosive. See Barton et al (2012) for instance.

       This is only a short-term measure because continued emission of carbon dioxide from human industrial activity will keep increasing the corrosiveness of the upwelled seawater in the California Current system. Another point to ponder is that the carbonate saturation state of the upwelled water is reflective of atmospheric CO2 several decades ago - when the source waters were last at the ocean surface. In other words, there is a considerable lag in saturation state of upwelled water in the California Current system, and it will take decades to catch up to the CO2 we have already emitted.

       Oyster farmers will have to come up with some cost-effective ways to combat the increasingly corrosive seawater there, or they will no longer be viable.

34896. greenhousegaseous at 09:00 AM on 4 August 2014
       2014 SkS Weekly News Roundup #31B
       

       Thanks for another week's worth of climate news!  FYI, the link for "What Climate Change Debate" invokes the Chi Tribune Pay Wall, so cannot be viewed by non-subscribers.

34897. MA Rodger at 05:18 AM on 4 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       jenna @9.
       If you are truly after making an accurate claim that you can defend, you will be needing more than a "yes" or a "no" answer. You could help yourself by giving the Eisenman et al paper a quick read. The final figure S11 looks quite fun - ominous for folk who want a simple "Antarctic Sea Ice is expanding" message. Antarctic Sea Ice levels are both rising and falling depending where you look which is why the net Antractic anomaly can shift +1,000,000 sq km in just a couple of weeks. And a quick perusal would also allow you to see the effect that Eisenman et al are agruing is a single step change of ~160,000 sq km which is small beer when compared with recent anomalies. That is probably what you think you're after as it is news on transitory records you're asking about.

       It would be fair to say that over the period of continual satellite coverage Antarctic Sea Ice has been increasing. The beef of the Eisenman et al paper is that the 160,000 sq km step change in 1991/2 makes a non-trivial change to calculations of linear trend, which is true. But the trend is still positive and that trend is not so linear in form. It increased in rate from ~2007, just as the negative Arctic trend increased in rate also from ~2007.

       Now what has got your denialist chums all aflutter lately is the recent year or so which has seen a very strong positive trend in the Antarctic coinciding with a period of high concentration suppressing negative anomalies in the Arctic. However if you want to rain on their parade, you simply point to the world not having started in November 1978. There are some satellite data prior to that which, with surface observations, have been used to compile HadISST back to 1870. There are a lot of gaps in that record which are bridged by straight lines, but it looks to me pretty conclusive that, just as the 160,000 km doesn't amount to a hill of beans in the grand scheme of things, the recent high Antarctic anomalies are also chicken-feed within the long view. The graph below is compiled from HadISST and taken from Tamino's Open Minds' site. It plots Extent in sq km.

       

       Tamino also did a pre-release item on Eisenman at al (2014). Withn this account Tamino analyses the relative geographical significance of the Arctic and Antarctic trends since 1978. Such a form of analysis was suggested by Eisenman (2010) and shows the Arctic decline over six-times greater than the Antarctic rise, something which may give the odd denialist pause for thought.

       

34898. jenna at 00:46 AM on 4 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       OK guys, all bs aside; Has Antarctic ice extent reached record levels or not? I am getting bombarded by some of my friends that are delialists and I need to be able to make my claim acurately and defend it!

       Thx,

       Jen.

       Moderator Response:

       [JH] Exactly what "BS" are you referring to? The OP?

       (Rob P) - It is indeed possible that winter Antarctic sea ice (extent) has reached record levels, but given that the decrease in the volume of summer Arctic sea ice is, on average, 10 times greater over the last several decades, and the combined loss of ice volume from ice sheets, icecaps, glaciers and sea ice in the last decade over 60 times greater, I wonder what they are trying to get at?  

34899. Leto at 23:42 PM on 3 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       Note, editing mishap in my comment at 3... Should read 'square miles of gain'. The point remains the same. It is clearly a propaganda piece with no attempt to weigh the evidence.

34900. MA Rodger at 22:50 PM on 3 August 2014
       Error identified in satellite record may have overestimated Antarctic sea ice expansion
       

       The full Eisenman et al (2014) paper is available on-line complete with "Supplemental Discussion and Figures."

       BojanD @6.

       If within your struggles you find yourself able to articulate the substance of that difference "not in favour of Eisenman et al," it may be worthy of further discussion. For myself, I see a significant difference between coverage that quotes Comiso as saying no more than Eisenman's 'error' is a non-issue having been already corrected and coverage that presents the difference between Comiso & Eisenman as but the likelihood Eisenman places on the potential for a 'post-2007' error being easily possible and the likelihood according to Comiso being non-existent. Further, that Comiso describes Eisenman et al (2014) as "misinformation" points to a bit of history between the two of them.

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