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The Daily Mail is wrong as usual. 2015 was the hottest year on record - and by a large margin. I figure the problem the Daily Mail has is that it wants us to think that we all live up in the sky.
As ATTP tweeted:
To solve global warming, everyone must move to the lower troposphere! https://t.co/Lw3H9JR9ue via @MailOnline— There's Physics (@theresphysics) January 7, 2016
Well - this is not the first and it won't be the last that someone confuses the measures of satellites and surface temperature. Thing is. the Daily Mail is going to have a lot of egg on its face in a few days, when the reports from NASA and NOAA are in, and a bit later when the report from the UK Met Office Hadley Centre is in. (Does a newspaper have a face?)
A curiosity with the lower troposphere record
The other thing is that I have a suspicion there's something not quite right with the satellite records. Look I could be very wrong. I'm not an expert by any means. However it seems to me that there's a break between the satellite and surface record starting some time around 2006. Look at the charts below and tell me what you think. If you've a mathematical and statistical bent, maybe you can tell me if I'm just suffering eye-ball-itis or if there could be something to it.
The charts below all shows the average of GISTemp and HadCRUT4 with the average of RSS and UAH. I've combined them, because the surface records are close to each other, and the satellite records are close to each other.
The first chart (animated) shows the record from 1980 to 2015. Note the surface temps for last year are only averaged to November, and the December temperatures might change that a little bit.
|Figure 1 | GISTemp and HadCRUT average vs RSS and UAH average for the period 1980 to 2015. Data sources: GISS NASA, UK Met Office Hadley Centre, UAH and RSS|
The second chart compares surface and lower troposphere up to 2006. I've marked the main ENSO events as well as Pinatubo. Although the linear trend lines are different, I'd say that's mainly because of the end points of each. The temperatures follow each other fairly well. The warming and cooling events are exaggerated in the lower troposphere compared to the surface, which is as expected.
|Figure 2 | GISTemp and HadCRUT average vs RSS and UAH average for the period 1980 to 2006. Data sources: GISS NASA, UK Met Office Hadley Centre, UAH and RSS|
This last chart is for the period from 2006 onwards. It's only for a very short period, so I could be wrong, but it seems to me that there was a jump down in the temperatures of the lower troposphere compared to the surface and I cannot think why that would be. It's as if the lower troposphere dropped from the La Niñas and unlike in earlier periods, it didn't recover. There was strong La Niña in 2010/11 ("one of the strongest on record") and the Bureau of Meteorology reports La Niñas in 2007/08, 2008/09 and 2010-2012. Then there was an El Niño in 2009/10 which does show up in the chart, as well as one in 2006/07. So it could just be the preponderance of La Niña. The PDO index was negative from 2007 until 2014, but the AMO was positive over that time. I don't know what effect they have on the temperature of the lower troposphere.
|Figure 3 | GISTemp and HadCRUT average vs RSS and UAH average for the period 2006 to 2015. Data sources: GISS NASA, UK Met Office Hadley Centre, UAH and RSS|
If anyone can explain the recent drop in the lower troposphere temperatures compared to the surface do tell. Why might it have become disconnected from the surface temperature? Was it just the preponderance of La Niñas? If so, why did it last so much longer than in earlier periods? I'd be particularly interested if you know of any papers on the subject - I couldn't find any.
There's a paper from 2003, by Carl Mears (of RSS) and colleagues, which will give you an inkling of the difficulties in working out the temperature of the air at different levels.
The UAH lower troposphere record has changed rather a lot between versions
There's one more chart worth looking at in this context, which was prepared by Nick Stokes of Moyhu fame. What it shows are the different changes that have been made to GISTemp and the changes that have been made to UAH over different periods of time for the record from 1980 onwards. It shows the difference in GISTemp for two periods - 2015 minus 2011 and 2015 minus 2005; and for UAH it shows the current version beta 6 minus the previous version 5.6. The satellite data has had much bigger changes than GISTemp has.
|Figure 4 | Comparison of changes made to GISTemp and UAH. Credit: Nick Stokes|
Misinforming framing from the Daily Mail
Getting back to the Ryan O'Hare article, it began with a lot of nonsense. If you just read the first part of his article, you'd swear that he cannot tell the difference between the surface and the air up high. He wrote:
For months, reports have claimed 2015 was the hottest year on record, with temperatures reaching unprecedented levels globally.
However, this title may have been awarded a little hastily after scientists in the US found evidence to suggest it was actually the third hottest year since records began.
By studying satellite data, their results contradict the previous readings and predictions made using land-based weather stations.
It's not until you read further that you see that maybe Ryan O'Hare does understand the difference. In fact, if you chopped off the first bit of silliness, you'd find quite a reasonable article. So whether it's Ryan O'Hare or some sub-editor denier looking for a sensational and provocative lead, I cannot say. If the latter, then Ryan would do himself a favour by writing for a responsible news paper and left the Daily Mail to the disinformers. Though that would probably just let UK people down altogether, They'd be stuck with unethical denialist writers like David Rose. (I noticed that Ryan O'Hare didn't tweet his Daily Mail article, so maybe he's a bit embarrassed by it - and so he should be.)
Fifteen of the hottest sixteen years were this century
Right down near the bottom is the clincher quote from Professor Jo Haigh of the UK Met Office:
'Whether or not 2015 was the warmest, or second or third warmest, is rather less important than the unquestionable observation that nine of the ten hottest years on record have occurred since 2005 and that each of that past three decades has been warmer than the previous, and warmer than any previous decade since 1850.'Well, looking at GISTemp, I make it eight of the ten hottest years since and including 2005, but I won't quibble too much. Here is a table showing how every year since and including 2001 are in the hottest 16 years on record. The only other year that made the grade was 1998. And we're only at 2015! The world is getting hotter and hotter.
Anomaly from 1951-1980 mean (°C)
References and further reading
Mears, Carl A., Matthias C. Schabel, and Frank J. Wentz. "A reanalysis of the MSU channel 2 tropospheric temperature record." Journal of Climate 16, no. 22 (2003): 3650-3664. doi: http://dx.doi.org/10.1175/1520-0442(2003)016<3650:AROTMC>2.0.CO;2 (open access)