choff wrote:Beck's paper describes in great detail how local conditions have to be taken into consideration during measurements, he describes Keeling's own mistakes in this regard. Also given is the acceptance of 19th century data in the Keeling curve described as too low by 19th century scientists from chemical processing errors.
I don't think I addressed this. Beck has not a leg to stand on. The ML data and ice core data are both good, and consistent, and expected , in the sense that we have been emitting a lot of CO2. BTW - of the emitted CO2 roughly 50% goes into the atmosphere, and 25% each into oceans and biosphere roughly. Which means that the extra CO2 is stimulating plants to grow more and the total volume of plant carbon has increased over the period. Whether this effect will continue (with dead plant carbon being removed from consideration) or whetehr it will saturate at some point is an interesting question.
If you don't accept this - and continue to claim high CO2 in pre-industrial times, could you please summarise what is Beck's hypothesis for CO2 level time series and what is his evidence for this, and I'll do a comparison with the standard hypothesis and look at quality of evidence etc. As far as I'm concerned this is incontrovertible, so I'm not going to rehash argument here unless given a definite alternate hypothesis from you.
Let me know.
Now, on the issue of TOA radiation balance, H2O measurements, etc, things are less clear. That is because this relates to feedbacks - not to forcing. IPCC puts the possible variation in feedbacks as high - because there is a lot of uncertainty, and some inconsistency in evidence from different sources.
It always amazes me the inconsistency of climate deniers here. They put up a straw man of "IPCC has is certain what feedbacks are" when they explicitly state a large uncertainty. They then highlight some (real or fabricated) uncertainty. There are real uncertainties here although again surprisingly deniers seem to go for fabricated ones. They then conclude that it is therefore certain (or nearly certain) that CO2 has no warming effect.
In an unprejudiced reality the real uncertainty about feedbacks means that we don't know the magnitude of the CO2 warming effect - and assuming it must lie at the low end of the uncertainty is a sort of wish-fulfilment fantasy, just as assuming it must lie at the high end is the reverse.
Glad you mentioned the radiosonde data, I'll repeat myself.
WUWT TOA Radiation budget claims
http://wattsupwiththat.com/2012/05/07/t ... new-paper/
This first WUWT post summarises work in 2012 on reanalysis of satellite data that was inconsistent. It is usually the case that initial data from any sensor has issues, especially when using it to identify long-term trends. Why are these so difficult? Because changes in equipment, software, measurement protocols, or just long-term stability can all affect results. Luckily there are usually multiple sources of data and by cross-checking everything carefully, drilling down to the error sources, and compensating for them you can clean up the signal. But it is difficult work.
If you don't trust the scientists doing this, reckon they are dishonest, then obviously you cannot accept their results. But in that case you still have the anomalies in the raw data that they note and which they use to make the corrections. You would need, for an alternate hypothesis, to do the same thing - cleaning up the data - but clean it up in a different way making different assumptions.
Or, you could adopt an extreme stance and say that the error is so bad that you will not accept it.
Personally, I'll go for cleaned up data as long as the cleanup is properly described and the algorithms used, and motivation for them, all carefully described. then if there are mistakes somone is going to find them.
The WUWT article does not identify any mistakes in this cleanup operation which results in the satellite data being more consistent with other datasets (and what is expected from surface measurements). I was sort of expecting it to reference a paper proposing a different explanation for the anomalies, or errors in the cleanup algorithms, etc.
I suspect what happened is that WUWT originally posted an attempt at this which was so thoroughly discredited that WUWT removed the link to it (AW does that - he has so many embarassing errors that he has to). So let me know if you have found a (not totally discredited) paper criticising the cleanup WUWT describes in this post. Otherwise this link is evidence for the consensus view and against your alternate view that lapse rate feedback is negative.
http://wattsupwiththat.com/2013/03/06/n ... ter-vapor/
Summarising - this WUWT article claims that NVAP TOA measurements of water vapor AND mid-troposphere measurements of temperature are self-consistent and together prove that H2O feedback must be negative.
It sounds good - does it not. It is however untrue. Seeing why it is untrue is really useful. There is a kernel of truth in the issue. Both sets of measurements are do not support the models and the generally accepted theory. But equally they do not support any other theory. They are currently too self-contradictory and full of error to support anything.
WUWT focusses on the "do not support the models" bit and turns that into "proves the models are wrong".
See the difference? I'm going to give evidence below.
Luckily there is other evidence for what is the TOA radiation budget apart from these two sets of data that WUWT concentrates on - because they are not much good. I'll give that later because this stuff is complex and takes time to write or read. But for those who want to go to the source the paper I'm going to discuss later on (in another post) is:
http://deepblue.lib.umich.edu/bitstream ... sequence=1
Table 2. Change of OLR by layer from water vapor and from CO2 from 1990 to 2001.
The calculations show that the cooling effect of the water vapor changes on OLR is 16 times greater than the warming effect of CO2 during this 11-year period. The cooling effect of the two upper layers is 5.8 times greater than the warming effect of the lowest layer.
This is true. It is what I posted earlier in response to the WUWT claims that CO2 is not a GHG. AW does not worry about internal consistency of his stuff so is quite happy to claim: (1) greenhouse effect can't happen because vertical; columns are saturated at infra-red and (2) greenhouse effect depends only on TOA concentrations of CO2 and H2O. These two ideas are directly contradictory: if one holds, the other is untrue. AW has no interest in a balanced understanding of the issues - he wants the maximum number of negative sound-bites.
Anyway, this one is broadly true - what matters for GHG forcing is concentration at TOA where the atmosphere becomes transparent at the relevant wavelengths. What matters for water vapor feedback is concentration of H2O at the same place. Exactly where this is I'm not going to check for now - because it turns out we will not be able to say much from this data anyway. We can always argue that later if it becomes important.
The Tropical Hot Spot
The models predict a distinctive pattern of warming – a “hot-spot” of enhanced warming in the upper atmosphere at 8 km to 13 km over the tropics, shown as the large red spot in Figure 8. The temperature at this “hot-spot” is projected to increase at a rate of two to three times faster than at the surface. However, the Hadley Centre’s real-world plot of radiosonde temperature observations from weather balloons shown below does not show the projected hot-spot at all. The predicted hot-spot is entirely absent from the observational record. If it was there it would have been easily detected.
This is untrue. The tropical hotspot is partially present in the observational record. That is, some datasets show it, some don't. I don't dismiss the fact that there is inconsistency in the data. There is. But equally the fact that some datasets don't show a hotspot when some do means we cannot draw clear conclusions from this set of observational data. It is a matter that remains to be resolved in the future with better observations. And it will be.
The hot-spot is forecast in climate models due to the theory that the water vapor profile in the tropics is dominated by the moist adiabatic lapse rate, which requires that water vapor increases in the upper atmosphere with warming. The moist adiabatic lapse rate describes how the temperature of a parcel of water-saturated air changes as it move up in the atmosphere by convection such as within a thunder cloud. A graph here shows two lapse rate profiles with a larger temperature difference in the upper atmosphere than at the surface. The projected water vapor increase creates the hot-spot and is responsible for half to two-thirds of the surface warming in the IPCC climate models.
All true except that the effect on IPCC models is complex. Yes, it is generally supposed (not assumed, but supposed on basis of other evidence) that H2o feedback is as stated overall. The evidence here, and the arguments here, relate only to the tropics where the atmosphere can be reasonably viewed as moist. Other mechanisms are possible elsewhere and you cannot assume that tropical and non-tropical responses are the same.
Conclusion
Climate models predict upper atmosphere moistening which triples the greenhouse effect from man-made carbon dioxide emissions.
Minor qualification. It is basic physical models of the atmosphere - not the complex much-distrusted GCMs - that make this prediction. It is true that the GCMs follow physics and so do the same thing. And this only applies in the tropics, where the physical modelling is simpler.
The new satellite data from the NASA water vapor project shows declining upper atmosphere water vapor during the period 1988 to 2001. It is the best available data for water vapor because it has global coverage.
OK - this is NOT true.
(1) The NVAP and NVAP-M datasets used here are only 22 years long. In climatological terms that is very short and given the errors usually found in any measurements not enough to predict long-term trends either way.
(2) The upper atmosphere satellite data here is especially flakey because the levels of H2O are low and the sensors from radiosondes have a time constant and remember previous moister values as the ballon ascends. The upper atmosphere values therefore depend on sensor time constant and balloon ascent rate. Over the period sensors have changed, making trend comparisons difficult.
(3) The NVAP and NVAP-M datasets are designed to provide good quality spatial coverage and resolution. What they don't provide is good long-term trend data, because they meld together data from many different sources each of which is available only for part of the 22 years period.
From the NVAP-M geophysics paper:
The results of Figures 1 and 4 have not been subjected to detailed global or regional trend analyses, which will be a topic for a forthcoming paper. Such analyses must account for the changes in satellite sampling discussed in the auxiliary material. Therefore, at this time, we can neither prove nor disprove a robust trend in the global water vapor data.
I have not yet found any such forthcoming paper - which probably means that they could not conclude anything about long-term trends - or maybe just that it is taking a long time. If you have a mind, you could take this absence of evidence as a plank in a conspiracy theory that such analysis is suppressed because the results would be damning for the consensus view. But NVAP-M is available - anyone can do a reanalysis and look at long-term trends. (BTW NVAP itself - the original dataset - is rubbish and superceded by the better quality reanalysed NVAP-M).
Calculations by a line-by-line radiative code show that upper atmosphere water vapor changes at 500 mb to 300 mb have 29 times greater effect on OLR and temperatures than the same change near the surface. The cooling effect of the water vapor changes on OLR is 16 times greater than the warming effect of CO2 during the 1990 to 2001 period.
The relative effects of H2O and CO2 can't be determined because of the lack of ability to determine trends. The WUWT article did not give error bars for the stated NVAP absolute water vapor levels, so we also don't know what is the relative effect of a given percentage change of H2O and CO2 (this is separate from what is the magnitude of the feedback, but still interesting). I'm sure the data is available from NVAP so this can and should be mended. Anyone want to do so?
Radiosonde data shows that upper atmosphere water vapor declines with warming. The IPCC dismisses the radiosonde data as the decline is inconsistent with theory.
Note there is no evidence for this assumption. In reality IPCC does not view this evidence as reliable for the known reasons given above. Now, maybe those are again an excuse generated by lying scientists - but in that case the errors in their papers could easily be exposed and corrected. Errors happen all the time and corrections are made (there have been a few famous examples of climate skeptics identifying errors which are subsequently corrected).
During the 1990 to 2001 period, upper atmosphere water vapor from satellite data declines more than that from radiosonde data, so there is no reason to dismiss the radiosonde data.
We'd need to look at this in detail. But I believe that this is no longer true given that satellite reanalysis you linked.
Changes in water vapor are linked to temperature trends in the upper atmosphere. Both satellite data and radiosonde data confirm the absence of any tropical upper atmosphere temperature amplification, contrary to IPCC theory. Four independent data sets demonstrate that the IPCC theory is wrong. CO2 does not cause significant global warming.
It follows that this overall conclusion is untrue.
Note also the aristotelian nature of the WUWT thinking. "IPCC theory" is right or wrong. The IPCC reviews existing literature, summarising hypotheses and observations. There is a wide range. If WUWT had not made all the above mistakes, and this conclusion about tropical upper troposphere water vapor trends were correct, it would certainly be significant, but it would only affect one small part of the interlocking theory and empirical data summarised by IPCC. It would highlight more clearly an inconsistency that needs further investigation. We have a small tag for this already because of the tropical hotspot mystery.
WUWT and associated sites almost never make a helpful contribution to the science because:
(1) they make so very many mistakes. It is very rare to find a post that is not clearly wrong
(2) they jump to conclusions and do not put individual points into context. There are many different ways to look at tropical radiation balance (and hence what is the H2O feedback) data from all of them needs to be put together to get the best overall evidence.
(3) There is a lot of uncertainty around this specific issue. The IPCC reports make this clear if you botehr to read them. WUWT posts do not make it clear - going from "uncertain" to "CO2 has no effect" in one bound.