WUWT is starting to look like its old self again after something of a hiatus. There's been a cross-post at WUWT of the UAH temperature update on Roy Spencer's blog, which was missed last month. I've covered that one already.
Now Christopher Monckton is back with his RSS charts (archived here), trying to claim they prove that global warming is a hoax, or global warming has stopped, or something like that.
RSS has been an outlier since 2011. It's as though something crept into the algorithm in 2011 and got stuck there. RSS has the least coverage of all four data sets, only going from 82.5N to 70S.
Temperature data comparisons
Here are two charts comparing all the data sets, including 2014 year to date average. The top chart shows all the data available in all four datasets. You can see how closely aligned they all are by clicking on the chart to enlarge it.
|Data sources: NASA GISS, Met Office Hadley Centre, UAH, RSS|
I've circled where RSS dropped way below the others and has never recovered. Is it a gremlin in the system or has it something to do with enhanced warming at the poles, which RSS is not picking up?
RSS and the southern hemisphere
To help unravel the mystery, I've plotted UAH and RSS, separating the northern and southern hemispheres. Click to enlarge as always.
|Data sources: UAH, RSS|
You can see immediately that the biggest difference is in the Southern Hemisphere. RSS only goes to 70S, so it misses out virtually all of continental Antarctica. By contrast, UAH goes down to 82.5S, so it only misses out on a smaller area. Whether its measurement can be accurate or not is another question. RSS states that the altitude makes a mess of the readings (Antarctica has mountains). By the way, I'm not assuming it's Antarctica. I don't have the data to go any further than showing there is a bigger difference in the southern hemisphere than the northern. To pin it down further would require a deeper investigation, which probably some people are doing.
Christopher Monckton's cherry picking bonanza
The first cherry Christopher picks is the RSS data set. He wrote:
Since October 1996 there has been no global warming at all
Which would provoke a grimace and groan from people who've been following the rise in temperatures. Here is what's happened since 1996:
|Data sources: NASA GISS, Met Office Hadley Centre, UAH, RSS|
And as I've shown previously, sea levels are rising, ice is melting and oceans are getting hotter.
Even the RSS data, which has that anomalous drop since 2011, shows only one year since 1996 that was colder than 1996 - and that only marginally:
|Data source: RSS|
Then further down in his article, Christopher asks:
When the November 2015 RSS data are available, how many years and months of zero global warming will have occurred?
Well, I can't answer that question. All I can say is that if you only pick the data that suits your message then you are intending to deceive your readers. And to confirm that, this is what Christopher wrote a bit further on:
But is the RSS satellite dataset “cherry-picked”? No. There are good reasons to consider it the best of the five principal global-temperature datasets.
Can you guess what is very first very "good" reason was? It's this:
The indefatigable Steven Goddard demonstrated in the autumn of 2014 that the RSS dataset – at least as far as the Historical Climate Network is concerned – shows less warm bias than the GISS or UAH records.
Wouldn't you know it. It's because it shows less warming. Not because it is representative. Not because it is in line with all the other data sets. It isn't. It's the stand out anomalous one. It's because he claims it shows what Christopher wants you to believe - that the world isn't warming - when it is. And just look who he cites as his "expert". One of the biggest deniers around - "Steven Goddard"!
Christopher then cherry picks the bits he likes out of a recent article by Carl Mears, who analyses the RSS data. He left out some crucial parts, for example, where Carl Mears wrote (my emphasis):
As a data scientist, I am among the first to acknowledge that all climate datasets likely contain some errors. However, I have a hard time believing that both the satellite and the surface temperature datasets have errors large enough to account for the model/observation differences. For example, the global trend uncertainty (2-sigma) for the global TLT trend is around 0.03 K/decade (Mears et al. 2011). Even if 0.03 K/decade were added to the best-estimate trend value of 0.123 K/decade, it would still be at the extreme low end of the model trends. A similar, but stronger case can be made using surface temperature datasets, which I consider to be more reliable than satellite datasets (they certainly agree with each other better than the various satellite datasets do!). So I don’t think the problem can be explained fully by measurement errors.
Model and observations - causes for differences
The blog article by Carl Mears is worth reading if you haven't already done so. He lists and describes four possible reasons for the difference between modeled projections and observations:
The possible causes for the model/observation discrepancies can be grouped into several categories:
- Measurement Errors
- Errors in Model “Forcing”
- Internal Variability (Random Fluctuations) in the Climate System
- Errors in Fundamental Model Physics.
Dr Mears acknowledges there could be measurement errors, but is of the view that this is less likely in the case of surface temperatures (as opposed to satellite-derived temperatures).
In regard to model "forcing", he points out, among other things, that modeled volcanic, aerosol and solar forcings turned out to be different from what actually happened, all of which would have made the models closer to the observations. Those forcings can't be predicted. Scientists have to wait to see what did happen and then allow for it after the fact.
With regard to internal variability, Dr Mears points out that "Even when such modes are well represented in a climate model, they most likely occur at different times than the real-world events, leading to differences between the modeled and observed time series." And that has been happening. The oceans have tended towards La Nina conditions for much of the last few years.
Dr Mears doesn't comment on the last possibility other than to say "I am not an expert in modeling, so I will leave the discussion of possible model errors to others with more expertise."
From the WUWT comments
Tom Harley complains that it could be the hottest year on record. He doesn't provide a link (deniers don't usually do that sort of thing), so here it is, straight from the WMO (not BoM) via the ABC.
December 3, 2014 at 8:17 pm
But, but, The Bureau of Meteorology, through their media division ‘their’ ABC, are telling us today that 2014 will be the ‘hottest ever’.
joelobryan says that the person who compiles RSS data is an idiot. So what does that make Christopher Monckton, one wonders.
December 3, 2014 at 8:18 pm
Dr Mears is an idiot who cannot accept the data.
When the data say elsewise, he says “Yeah, Verily.”
The sign of true faith-based believer.
//Joel O’Bryan, PhD//
masInt branch 4 C3I in is says it's all a hoax, and is possibly a Poe, but by definition who can tell?
December 3, 2014 at 8:43 pm
I suspect that persons at NOAA have already been ordered, “do IT, God Damn IT, or be FIRED”, to fabricate “data, i.e. observations” in order to appease Obama and save the names of the Saints of Global Warming, James Hansen and Albert Gore, and for no other reason.
Global Warming needs ObamaCare, and ObamaCare DESPERATELY NEEDS, at any and ALL COST NO MATTER THE BODY COUNT, WHICH MUST BE HIGH, Global Warming!
Ha ha. Sorry Old Obama-Boy. No Body Count, No Warming. NO OBAMACARE. Yea right, like Obama actually cared. Ha.
Nick Stokes mildly points out the cherry pick, referring to another WUWT article from the other day:
December 3, 2014 at 9:26 pm
“But is the RSS satellite dataset “cherry-picked”?”
As Werner noted (see Appendix), it’s now about the only one showing a period of non-zero trend “worth mentioning”.
wickedwenchfan, if you're reading this, Gavin Schmidt has answered your question. CO2 accounts for about 19% of long wave absorption in "all sky" conditions, including clouds.
December 3, 2014 at 9:51 pm
Does anyone know what the “consensus” is on the total contribution of CO2 as of today to the overall claimed “Greenhouse Effect”?
If you google it you get “mainstream climate scientists” citing anywhere between 9% and 26%! The number for the total Greenhousyness of our greenhouse gasses is 33-34C. An exact “official” number here would be appreciated too. It’s kind of hard to properly debunk someone when they don’t give you hard numbers to debunk with!!
john karajas talks about convective heat transfer from the troposphere to the stratosphere. He doesn't describe the mechanism. He also thinks "it's all too hard".
December 3, 2014 at 10:55 pm
Which just goes to show that convective heat transfer from the Troposphere to the Stratosphere trumps any increased heat storage capacity by carbon dioxide. Also, let’s not forget albedo affects from increased cloud cover. Does this mean that the Earth’s atmosphere is a complex system that is not conducive to modelling by a computer program? Oh yes it does!