Recent Comments
Prev 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 Next
Comments 29901 to 29950:
-
Tom Curtis at 04:57 AM on 2 May 2015Climate sensitivity is low
Klapper @343:
"The 2000 to 2010 average TOA energy imbalance is +0.95W/m2."
1) I need to make a correction. I assumed that Smith et al presented a median value based on their use of a box plot. In their supplementary information, however, they describe the central value as a mean, and the "first quartile" and "third quartile" values as being minus and plus one standard deviation respectively, with whiskers showing the range. The values are given as 0.73 +/- 0.13 W/m^2 with a range from 0.43 - 0.97 W/m^2. These values are stated as being the anomaly values with respect to the preindustrial era - anomaly values being used as a correction for model drift.
2) As noted before, the difference between observations and models over this period in Smith et al is 0.11 W/m^2. Even using your uncorrected values, the difference between observed and modelled TOA energy imbalance from 2000-2010 is still only 0.33 W/m^2. The +/- 2 sigma range of the observed TOA energy imbalance is 0.06 to 1.18 W/m^2. So, even on your figures the discrepancy between mean model and mean observed TOA energy imbalance is substantially less than 0.5 W/m^2 (which as I said before, is a fiction). Further, you are making a case that the models are shown to be seriously flawed because, the modelled TOA energy imbalance lies within error (actually, withing 1.2 SDs) of the observed value. It may make a good emotive argument, but it is certainly not a scientific argument.
-
Klapper at 03:58 AM on 2 May 2015Climate sensitivity is low
@MA Rodger #341:
".. reducing your mismatch from the range 0.19-0.49 W/m2 to 0.06-0.36 W/m/2, considerably reduced from the originally stated 0.5 W/m2"
You're forgetting the originally stated comparison was to OHC, not global energy imbalance (although as noted OHC pretty much is the bulk of the energy imbalance). In any case, even reduced, the numbers support my hypothesis the models run too hot.
"..implies that the aerosol forcing is about -1.6 W/m2"
Circular logic but that's a topic for whole discussion on itself. I'll say no more.
"..would more recent models be expected now to conform to Hansen et al (2012)?"
I'm using the more recent models (CMIP5) and they don't conform to Hansen et al 2012 (still too hot). I'm tempted to go get the AR4 model ensemble and try that also, but for now I'm off to work.
-
Klapper at 03:49 AM on 2 May 2015Climate sensitivity is low
@Tom Curtis #340:
"..The IPCC uses just one model run per model in calculating multi-model means for a reason."
Yes very egalitarian of them. An argument could be made for using the other ensemble which says, the better resource supported models have more runs and are probably more realistic than the less resourced models. However, it doesn't make much difference, as the 2005 to 2010 average TOA imbalance changes from 0.92 to 0.90W/m2 with the one run per model ensemble.
"..What are your results for 2000-2010 for comparison with the Smith et al data?"
The 2000 to 2010 average TOA energy imbalance is +0.95W/m2.
".. rather than the multi-model median as do Smith et al?"
I would have to download all the models, a very tedious process, and create my own median; KNMI only options a mean in their ensemble exports.
-
Klapper at 03:39 AM on 2 May 2015Climate sensitivity is low
@KR #338:
"I don't think you can make any significant conclusions from such a short period of data".
The quality data for OHC only begin since the ARGO system reached a reasonable spatial density (say 2004 at the earliest). However I will look for some longer OHC/global heat gain data/estimates to match longer periods, say a 15 year period from 2000 to 2014 inclusive. The average for that period is a TOA energy imbalance of 0.98W/m2 from the CMIP5 ensemble (multi-runs per model) mean rcp4.5 scenario.
-
billthefrog at 03:38 AM on 2 May 2015Inoculating against science denial
@ Straight Talkin
One of my old university chums is now a head of department at the London School of Hygiene & Tropical Medicine. In about 2 months time, they will be running a course called... "Epidemiological evaluation of vaccines: efficacy, safety and policy". Perhaps you should drop them a line and explain that they've got it all wrong.
-
MA Rodger at 02:06 AM on 2 May 2015Climate sensitivity is low
Klapper @337.
You are getting your 0.58 W/m2 +/- 0.15 from Hansen et al (2012) , a paper which states:-
"The fact that Earth gained energy at a rate 0.58 W/m2 during a deep prolonged solar minimum reveals that there is a strong positive forcing overwhelming the negative forcing by below-average solar irradiance. "
I would suggest that such a quote is difficult to ignore, although you apparently do overlook it. It sort-of adds weight to the comment by KR @338. From memory, the negative solar forcing through those years between cycle 23 & 24 was something like -0.13W/m2, reducing your mismatch from the range 0.19-0.49 W/m2 to 0.06-0.36 W/m/2, considerably reduced from the originally stated 0.5 W/m2.
The paper goes on to say:-
"Measured Earth energy imbalance, +0.58 W/m2 during 2005-2010, implies that the aerosol forcing is about -1.6 W/m2, a greater negative forcing than employed in most IPCC models." and "Most climate models contributing to the last assessment by the Intergovernmental Panel on Climate Change (IPCC, 2007) employed aerosol forcings in the range -0.5 to -1.1 W/m2."
Again, here is very relevant data you overlook. If these AR4 models underestimate negative aerosol forcing, you would expect them to run with a greater TOA imbalance. And if they did so in AR4, would more recent models be expected now to conform to Hansen et al (2012)? Or is that a bit of an assumption on your part?
-
Tom Curtis at 01:46 AM on 2 May 2015Climate sensitivity is low
Klapper @337:
1) Did you compute (∑rlut x 1/n) + (∑rsut x 1/n) - (∑rsdt x 1/n) or (∑(rlut + rsut - rsdt)) x 1/n?
2) The IPCC uses just one model run per model in calculating multi-model means for a reason. Failing to do so allows a few models with unusually large numbers of runs to be more heavilly weighted in the absence of evidence that those models are superior, and indeed, regardless of any evidence of their superiority or inferiority. In particular, one model with multiple runs is the GISS model ER, which you have previously stated has a TOA energy imbalance from 2000-2015 of 1.2 W/m^2 - ie, it is at the high end of the CMIP 5 range, and above the CMIP 5 multi-run mean as calculated by you. There is reason to think this distorts your result.
3) 5 years is too short a time for such comparisons for reasons given by KR. What are your results for 2000-2010 for comparison with the Smith et al data? Indeed, what are your results for all of the Smith et al periods as shown in the second panel of the first graph in my post @322?
4) Why do you use the multi-model (really multi-run) mean rather than the multi-model median as do Smith et al? In this case where damage functions are not a factor, using the median as the central estimate makes sense (IMO) in that it is less subject to distortion by outliers. Is their some reason why you preffer it despite this disadvantage?
5) I ask you to forgive me for not responding to your earlier posts. I had an extensive response prepared and lost it in the attempt to post it. Unfortunately I have been ill since then, and not had the energy for recomposing a similarly extensive response. I am also considering whether or not to download the data from KNMI for direct comparison before more detailed response (which will take more energy and concentration).
-
KR at 01:13 AM on 2 May 2015Climate sensitivity is low
Klapper/everyone - I'll note that many of Klappers issues with model fidelity have been discussed at great length over on the Climate Models show remarkable agreement with recent surface warming thread. And on that thread Klapper was shown (IMO) that his arguments did not hold.
This appears to be yet another search for a (notably short term, and hence statistically insignificant) criteria with which to dismiss modeling.
-
KR at 00:45 AM on 2 May 2015Climate sensitivity is low
Klapper - 5 to (at most) 15 year periods are short enough that statistical significance is lacking, and that the model mean is expected to differ from short term variations such as ENSO.
I don't think you can make any significant conclusions from such a short period of data.
-
Klapper at 00:09 AM on 2 May 2015Climate sensitivity is low
@MA Rodger #334:
To cross-check my model vs actual comparison for TOA energy imbalance I extracted at the KNMI Data Explorer site data from the CMIP5 Model Ensemble RCP 4.5 (all runs) the variables rsut, rlut, and rsdt, monthly data. I averaged the monthly global data into annual global numbers and calculated the TOA energy imbalance per year as rlut + rsut - rsdt.
To compare to a published number, in this case I'll use the Hansen et al number from the GISS website linked above, I averaged the years from my model extraction data, in this case 2005 to 2010. The GISS number for global TOA energy imbalance of 0.58 W/m2 +/- 0.15. This agrees with other published estimates of similar time periods.
The average I get from my CMIP5 RCP 4.5 ensemble annual data, 2005 to 2010 inclusive is 0.92 W/m2. The models appeart to be running too hot by a substantial amount.
My next experiment will be to compare these TOA CMIP5 data to OHC over a longer period, say 2000 to 2014 inclusive. Or maybe just OHC from 2005 to 2014 since the ARGO spatial density was essentially full coverage after 2004 or 2005. We can likely agree that the global energy imbalance dominantly present in the ocean heat gain, although some of the imbalance goes into the atmosphere and melting continental ice.
-
knaugle at 22:54 PM on 1 May 2015Heartland takes climate foolishness to a Biblical level
The articles I've read on this included comments from another Heartland Inst. representative, Lord Christopher Moncton, whose reputation as a "top climate scientist" is well known to readers of SkS.
-
Tom Curtis at 16:09 PM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
Tristan @22, seeing you ask, we have this from a recent, paywalled article, Unabated planetary warming and its ocean structure since 2006:
Also this from Purkey and Johnson 2010 for the 1990s and 2000s:
-
Tristan at 15:43 PM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
TC, are you aware of a graph that looks at warming rate vs depth?
-
Tom Curtis at 12:46 PM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
scaddenp @19, absolute heat content makes sense with respect to the heat content of the components at absolute zero temperature in a solid state. That is part of the definition of absolute zero. I agree, however, that the OHC anomaly is a far more usefull value. Also, it can be determined with a much lower error margin.
sauerj @20, your OWSALT would closely approximate to the "average temperature increase in the oceans" which deniers love to quote because its low numerical value is wonderfully deceptive. Here is an example from Bob Tisdale:
It is deceptive because nobody would care if the surface was warming as slowly as the average temperature increase across the ocean depths. Of course, it is not. It warms much faster and that creates a problem.
Further, such a measure has almost no scientific value. Surface temperature and OHC (or better Global Surface Heat Content, bearing in mind that the entire ocean is less than 0.2% of the radius of the Earth) both have immediate scientific import, being values in the equation for climate sensitivity as calculated by energy balance. OHC is a direct factor in the time taken to reach equilibrium, and surface temperatures are the governing value for the effects of reaching equilibrium. Both, therefore, are usefull. In contrast OWSALT as an index just ignores usefull information.
-
sauerj at 11:11 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
Picking up on ryland's 1st post: Is an "Overall Weighted Average Sea+Land Temperature" published anywhere (calculated based on the following)?:
OWASLT = Sum(Temp x Mass x Heat Capacity) / Sum(Mass x Heat Capacity), and looking at all pieces of mass components in the atmosphere + mass in the ocean (say down to 2000m or whatever depth would appropriate with respect to available global data & that should rightfully be included for an all inclusive weighted average temperature like this).
By combining everything into one OWASL temperature, this would then remove all the surface-only decadal swings caused by the shoshings back & forth between land & deep sea.
If total sea OHC is known (which is simply = temp x mass x Cp), then obviously sea temp is also known for all sea global locations and for all sea depths. Therefore, deriving the above OWASL temperature is 'doable'.
If sea OHC has continually & steadily been rising, and since this mass x Cp is 93% of the total mass x Cp of the globe, then obviously if a OWASLT was reported, then it would also be steadily climbing year after year on the same steady rate (even during the last 10 years when the rate-of-rise of surface-only temps was less than the 1990's). Having such a metric would remove all doubt that comes by only looking at the surface-only temp. And remove all contrarian ammunition, because there would be no hiatus in temperature rise using a metric like this.
Does anyone calculate & report an OWASL temp like this as their single, all inclusive metric number?
-
scaddenp at 11:03 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
Dont take this as gospel but I think it more complicated than that. An absolute OHC doesnt make a lot of sense. With respect to what? Absolute zero? freezing temp of water? What would you do with this number?
What I believe is actually calculated is change of temperature against the average of 1955-2006 temperature. The delta temperature plus heat capacity of seawater is then used to calculate OHC. This is a useful number.
-
Ken in Oz at 10:28 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
The ups and downs, pauses and accelerations come from surface air temperatures being a consequence of sea surface temperatures, which are variable over decades due to ocean currents, overturning - ie things like ENSO, PDO. Warming overlays this variability.
But, presuming I read the article correctly, if we are waiting for the "hiatus" to end in a hockey stick, it will probably be after PDO shifts phase? I suggest - based on Foster and Rahmstorf's "Global Temperature Evolution" - that even a 'less likely due to PDO' el Nino or two will send us into record temperatures even without that shift. A positive PDO will just make the upturn more short term consistent and steeper.
-
WxChief at 09:40 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
scaddenp - Is there an accepted value for the average 1955-2006 OHC?
-
KR at 09:20 AM on 1 May 2015Climate sensitivity is low
Scaddenp - We do have XBT data below 700m, just rather less of it. Which is how the ocean heat content analyses going back to the 1950s have been done.
-
scaddenp at 07:43 AM on 1 May 2015Climate sensitivity is low
Klapper - you are proposing to ignore OHC pre-Argo because there is only data to 700m. However, if you wish to postulate that the huge change in OHC 0-700m does not mean energy imbalance, then you must also be proposing that there could somehow cooling of the 700-2000 layer to compensate for warming in the upper layer.
I would also be interested in your opinion on the Loeb et al 2012 paper in claiming that models and observations are at odds.
-
scaddenp at 07:32 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
WxChief - please note the OHC quoted is actually change is OHC since baseline (average of 1955-2006). There is very sparse data below 2000 but given mixing mechanisms available, it is not expected to be large. Furthermore it is constrained by steric sealevel rise (the Trenberth 2009 paper looked at this accounting exercise).
-
scaddenp at 07:19 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
Ryland, please accept my humble apologies for the "well duh". As a some time moderator on this site, my fault was doubly bad. It was an unfortunate knee-jerk reaction to what appeared to me as a straw-man argument.
-
WxChief at 06:14 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
The ocean heat content graphic shows an increase over about 50 years of about 30x10^22 Joules for the top 2 km. What percent is this of the total? Is there an estimate for the total heat content of the ocean?
-
Tom Dayton at 05:54 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
ryland, I've responded to you on the It's Not Us thread.
-
Tom Dayton at 05:52 AM on 1 May 2015It's not us
ryland (from another thread), you should read Michael Tobis's explanation of how the IPCC's explanation of attribution usually is mis-spun or even dis-spun by the media, and in particular by Curry.
-
KR at 05:45 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
It can be challenging to avoid becoming short with new participants, especially if the points raised have been discussed at great length in previous discussions with others. There are numerous pseudo-skeptic arguments that are considered 'zombies' because they keep being raised despite repeated refutation, and quite frankly the question of attribution for climate change is one of those (see the It's not us thread, ranked as the 56th most common climate denial myth). After a while it becomes tiring to refute a poor assertion for the Nth time...
My personal approach is to point new participants to the relevant information as much as possible - and save sharper tones for those who continue to repeat incorrect assertions in the presence of evidence to the contrary.
-
ryland at 05:20 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
Phil@10 You may possibly be right. However if "well duh" is the accepted way on SkS of addressing posters who are not climate scientists and use imprecise sentences then so be it. Although that said, "well duh" may not be the best way to get the recipient of the post to immediately see the valdity and irrefutable logic of a particular argument. Moving on: KR as you suggested I am reading the views of both Gavin Schmidt and Judith Curry on attribution. Hard for me to digest in a single sitting but at the risk of another "well duh" a significant difference seems to be in Curry's use of 30 year periods and Schmidts dismissal of these as being too short to accurately evaluate the effects of natural factors. By the way I didn't see a single "well duh" from either Scmidt or Curry
Moderator Response:[TD] For discussions of attribution, the "It's Not Us" thread would be better than this one. Note there are three tabbed panes--Basic, Intermediate, and Advanced.
-
Phil at 04:22 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
ryland: "This suggests that factors other than human activity have an effect on global temperatures."
The idea that only human activity has an effect on global temperatures would mean that the production of CO2 on earth, could somehow eliminate the 11 year Solar cycle on the Sun, and ensure that volcanic activity on Earth suddenly became uniform. Such an implausible hypothesis is perhaps the reason that your comment received the Well duh! response.
-
ryland at 03:15 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
KR@8 Thank for your courtesy and especiailly for your reply. Both are much appreciated. No, I wasn't referring to you as your post at 4 was both innocuous and informative. Additionally, from your responses at 4 and 8 I doubt very much if you would even consider making derogatory remarks
-
MA Rodger at 01:40 AM on 1 May 2015Climate sensitivity is low
Given the preceding thread at the Guardian prior to the start here at SKS, was a thread discussion beginning here and running to 7,000 words of comment with nothing resolved, I would suggest a little discipline is required here at SKS to prevent it becoming another pantomime.
The issue to hand is "the missing 0.5W/m2 between models and reality." Such a quantity was identified @322 as having been "based on old figures from CMIP 4 and far less accurate observations, and even then is exaggerated by rounding."
This is refuted @330 as being "absolutely not true" because the missing 0.5W/m2 is apparently a different 0.5W/m2 to that identified @322, and for which we await a full description.
Looking back at the Guardian thread, the 0.5W/m2 appears here as the difference between study-based "heat gain in the measurable part of the ocean .. in the range of 0.3 to 0.6 W/m2" yielding a "best guess at ocean heat gain (of) 0.5W/m2" and "Models show(ing) the imbalance at the top of the atmosphere through this period as being 1.0 W/m2."
So what period? What models? Is the TOA 1.0 W/m2 anything to do with the "TOA energy imbalance projections from the models (of) ... currently about 1.0 to 1.2 W/m2" mentioned in the Guardian thread here?
Please let us not spend many thousands more words without a grip on what is being discussed.
-
Rob Honeycutt at 00:51 AM on 1 May 2015Climate sensitivity is low
Klapper @328... Just to trying to simplify things here, so your key issue is that measured changes in OHC data (W/m^2) do not match model results for TOA imbalance.
-
KR at 00:12 AM on 1 May 2015The climate 'hiatus' doesn’t take the heat off global warming
ryland - If your 15:41 comment is directed to me (that isn't clear), and I have been overly brusque, my apologies. However, I have frequently run across the assertion that it's impossible to measure temperature anomalies, sea level rise, and the like to the acccuracies stated in peer-reviewed literature, and that assertion is incorrect.
The math behind the Law of Large Numbers goes back to Jacob Bernoulli in 1713, and is based on the statistics of measurements and random errors. A sufficient number of measurements describes a probability function around the correct value, and the more measurements you make the tighter the bounds of that probability, the higher the accuracy. That accuracy rapidly becomes smaller than the precision of any individual measurement. Given 'n' measurements and a measurement error with a standard deviation of 'S', the uncertainty scales with the number of measures by:
uncertainty = S / n0.5
Again, the simple case of dice is illustrative. If you roll a die five times, you might get the numbers 2, 5, 3, 6, 5, with a mean value of 4.2. But as you roll the die over and over, the measured mean value (assuming, of course that the die isn't loaded) will converge towards the real average of 3.5. After 10000 rolls the uncertainty in the estimate of the mean will 100 times smaller than the standard deviation of a single die roll, far below the single digit resolution of the die faces.
If the die is loaded, the measured mean value will be different, providing a reasonable test of whether or not the die is fair.
Of course, the measurements might be biased high or low, which would be a systematic error. But additive systematic errors (offsets) are wholly cancelled out by looking at changes, at the anomalies. Systematic errors in scaling (such as XBT issues with speed of descent for ocean heat content) can be identified by proper calibration and cross comparison with other measures such as ARGO - and once found they can be corrected to produce a consistent and accurate record.
-
DSL at 23:43 PM on 30 April 2015Inoculating against science denial
StraightTalkin, see figures 1, 2, and 3 here:
http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6204a1.htm#Fig2
The time series is explained extremely well by the spread of vaccination programs and outbreaks in unvaccinated populations. If you accept the vaccination mechanism for these diseases, you should at least find the mechanism highly plausible for other diseases.
Good sanitation and nutrition will help prevent disease, but they won't cause the precipitous declines described by those graphs. Kids were washing their hands in the 1950s and 60s. Nation-wide (US) improvements in nutrition do not coincide with the precipitous declines described by those graphs. -
Climate sensitivity is low
Klapper - My apologies, S10 in Levitus et al is for the thermosteric component, while S1 shows the OHC (1022 J). Again, there is sufficient data to establish a long term trend against sampling uncertainties 0-2000m.
-
Climate sensitivity is low
Klapper - The XBT data does go to (and through) 2000 meters. Yes, XBT data back to the 1950's is sparse below 700 meters, but it is still data, and uncertainties due to sparse sampling are considerably smaller than the ocean heat content trends over the time of observations.
Again, I would refer you to Levitus et al 2012, in particular Fig. 1 and the supplemental figure S10, which shows the 0-2000m 2-sigma uncertainties, variances, and trends for each ocean basin. We have enough data to establish long term OHC trends with some accuracy.
-
PhilippeChantreau at 23:18 PM on 30 April 2015Inoculating against science denial
StraightTalkin, that is a pile of nonsense. I'm not interested in books, where anyone can say anything they want. Peer-reviewed scientific evidence leaves no doubt as to the efficacy of vaccines. The recent outbreak of measles in various places in the US where gullible people believe books or blond bimbos instead of their pediatrician have shown all we need to know about the effectiveness of vaccines.
-
Jim Eager at 23:09 PM on 30 April 2015The climate 'hiatus' doesn’t take the heat off global warming
ryland: "This suggests that factors other than human activity have an effect on global temperatures."
No one suggests that there aren't factors other than human activity that can affect global temperature. Except those setting up straw men to knock down, of course.
That said, other than an increase in solar intensity (the sole source of energy in) - which has not happened as it has in fact been the opposite recently, none of the internal variability factors that affect global temperature could have produced the monotonic warming over 35 years that we have observed. On the contrary, they all eventually revert to the mean.
-
Jim Hunt at 22:56 PM on 30 April 2015There is no consensus
We seem to wandering rapidly off topic? Perhaps this is a more appropriate location to continue this conversation?
http://www.skepticalscience.com/Has-Arctic-sea-ice-recovered.htm -
CBDunkerson at 22:07 PM on 30 April 2015Inoculating against science denial
Straight Talkin, you are deluding yourself. Setting aside your fiction based dismissal of the effectiveness of the polio vaccine... smallpox? Diptheria? Rubella? Tetanus? Heck, measles?
If you really believe that vaccines haven't vastly reduced the number of infections from these and other diseases you just are not grounded in reality.
-
Straight Talkin at 19:48 PM on 30 April 2015Inoculating against science denial
Although I agree with the general tenor of the article I challenge anyone to read 'Dissolving Illusions: Disease, Vaccines, and The Forgotten History' 2013 and still believe that vaccinations achieve any real benefits. Most things that they vaccinate for have very little risk in societies with good sanitation and nutrition. Everything that is vaccinated for was already well on the way to either being erradicated or had receded to a minor condition. Polio had become a very rare condition with a temporary upswing in the 50's, most probably due to DDT poisoning which has the same symtoms. After vaccinations for polio began many conditions that had similar symtoms were differentiated from polio whereas before they were often classified as polio. These conditions are not affected by polio vaccination. That is just the tip of the iceberg with regards to the level of misinformation about how 'vaccines safed us from all of these dangerous deseases'. Some of them actually make it morelikely to get it more severely after a few years. I consider myself a very objective person and the science on human created climate change is overwhelming. The science behind vaccinations effectiveness and safety is not.
-
Klapper at 17:40 PM on 30 April 2015Climate sensitivity is low
@Tom Curtis #322:
"...That Klapper is still using it shows he is clinging to old data simply because it is convenient for his message..."
Absolutely not true (and an unecessary cheap shot to boot). I extracted the multi-run per model ensemble mean numbers from KNMI data explorer, CMIP5 rpc4.5 scenario. I also checked one individual run from the GISS EH2 model, same emissions scenario (although it makes no real difference between the scenarios in the 2005 to 2015 period).
I used the rlut, rsdt, and rsut variables (absolute values, not anomalies) to calculate my net. I'm looking into the difference between my Net TOA imbalance and Smith et al, but not tonight.
-
Klapper at 17:29 PM on 30 April 2015Climate sensitivity is low
@KR #327:
The problem is the XBT data only go down to 700 m. If I had tried to use only 0-700 heat gain as my metric, I would be jumped on big time since I was "ignoring" the deeper ocean. The amount of sampling below 700 m prior to the ARGO network is extremely sparse, as noted in the Smith et al paper, particularly in the southern ocean.
-
Klapper at 17:25 PM on 30 April 2015Climate sensitivity is low
@Rob Honeycutt #326:
"...assuming they have to be somehow correct..."
Oh I don't assume they have to be correct at all. You can take the Net observations (satellite) from the Smith paper and throw them in the trashcan. However, that's not true of the ARGO data. Our knowledge of ocean heat is much much better since 2005 or 2004 than pre 2005 or 2004.
-
ryland at 15:41 PM on 30 April 2015The climate 'hiatus' doesn’t take the heat off global warming
Thank you for your "Well duh!" . I trust that if you are participating in the MOOC your responses to students will be somewhat less denigrating even if you regard questions asked/comments made as infantile. Having been a university professor for a very long time, I can assure you students regard responses such as "Well duh!" very unfavourably indeed.
-
jja at 13:59 PM on 30 April 2015Heartland takes climate foolishness to a Biblical level
What does the Heartland Institute and Satan, Prince of Darkness have in common. . .
Moderator Response:[PS] Very close to the line here.
-
Climate sensitivity is low
Klapper - It is wholly unreasonable to discard ocean heat content data prior to 2005. While the XBT data has higher uncertainties than ARGO, and there have been several calibration issues with it that are recently resolved, the sampling back to the 1960's is more than sufficient to establish long term growth in ocean heat content. There simply isn't enough deviation in temperature anomalies over distance to reject long term warming of about 0.6C/decade even with sparse XBT sampling.
For details on this, including evaluating the standard deviation of anomalies against distance, see the Levitus et al 2012, specifically the "Appendix: Error Estimates of Objectively Analyzed Oceanographic Data", which speaks directly to this matter. The uncertainty bounds from Levitus et al are shown in Fig. 2 here. And they are certainly tight enough to establish warming.
-
Rob Honeycutt at 12:53 PM on 30 April 2015Climate sensitivity is low
Klapper... The Smith etal paper that Tom links to bears reviewing, especially the summary and conclusions. This sums up some of the things I've been attempting to state with regards to the relationship between observations and models, where I've said that it's reasonable to conclude that the models are better representing the climate system and our observations are challenge our ability to "close the Earth's energy budget."
What I see you doing (or at least believe I see you doing) is getting stuck in down in the weeds of our observations, assuming they have to be somehow correct. I think that's a misdirected approach. As I've said several times in our conversation so far, there are lots of uncertainties in the empirical evidence and the models are there to contrain those uncertainties.
-
Klapper at 12:04 PM on 30 April 2015Climate sensitivity is low
@Tom Curtis #322:
"...First, ...the TOA energy imbalance...from observations and models match closely except for the period of 1972-82"
Where would you get observations from 1972 for the TOA energy imbalance? For that matter exactly how accurate are the current observations for the TOA imbalance? There's an post over at the Guardian on the water vapour/climate change story by "MaxStavros" which claims the satellite numbers in raw form show an imbalance of 6.5W/m2 at the TOA. Since we know that is impossible the number has been adjusted down to something more believable. I can understand the instruments on the satellite are precise but not accurate, but that means the "observations" are not that reliable. I'm guessing the most reliable number is ocean heat, but that is true only since the ARGO era, from 2004 or 2005. From the NODC data, the warming rate of the oceans, corrected to global area, is about 0.5 W/m2. This is close to other estimates. The following example is ocean plus melting, plus land, but since most of the heat goes into the oceans we would expect the ocean only and total should be close (and they are).
Here's a quote from Jame Hansen et al 2012 at the NASA website: "We used other measurements to estimate the energy going into the deeper ocean, into the continents, and into melting of ice worldwide in the period 2005-2010. We found a total Earth energy imbalance of +0.58±0.15 W/m2 divided as shown in Fig. 1"
http://www.giss.nasa.gov/research/briefs/hansen_16/
Here's the problem with an energy imbalance of +0.58W/m2: the models show a much larger TOA energy imbalance. The GISS model shows +1.2W/m2, and the CMIP5 ensemble mean is +1.0 W/m2 for the 2000 to 2015 period.
Moderator Response:[JH] Link activated.
-
Klapper at 11:38 AM on 30 April 2015Climate sensitivity is low
@Rob Honeycutt #321:
"... who are the experts you're asking?..."
You, and Tom Curtis and if not direct me to the peer-reviewed research that you know of. I admit I have in the past used Skeptical Science as a sounding board for ideas I have, since after a few back and forths on the numbers I can normally see if there is a concrete reason to reject the reason or not.
-
Tom Dayton at 11:24 AM on 30 April 2015Climate sensitivity is low
Perhaps Tom Curtis might use this recent study to add to the "It's the Sun" post, a counter to the myth that the Earth's temperature still is catching up to the increased input from the Sun that happened before around 1960? The counter to the myth is that if the myth is true, energy imbalance should be decreasing since then, as the increased outgoing radiation due to the Earth's higher temperature increasing compensated for the now-stable input from the Sun. Pretty please?
Prev 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 Next