Monday, July 22, 2013

About 97% or so consensus on AGW - close enough

Somehow it looks like the study [1]  of John Cook and the Skeptical Science team has touched a nerve.
There seems to be a high level of ridicule launched via several "skeptical" sites and by "skeptical" bloggers. [4],[5],[6]
Some scientists of "skeptical" view are standing up and claiming that their work has been wrongly rated - even when the team had sent requests to thousands of researchers to self evaluate their work as well.
Somehow it feels like the response from "skeptics" is out of proportion.
The results of the study are not new [3] nor controversial. They simply indicate that there is no significant debate in climate science about the role of humans in the warming of the climate. [2]
"From the 11 994 papers, 32.6 per cent endorsed AGW, 66.4 per cent stated no position on AGW, 0.7 per cent rejected AGW and in 0.3 per cent of papers, the authors said the cause of global warming was uncertain."
Of the research papers that take a stand on the subject 97% say we are making an impact. And if one evaluates all papers included in the study they find that 0.7% are opposing the notion of Anthropogenic Global Warming (AGW).
Naturally, there are differences regarding the severity of human impact but that and other details are very hard to gauge in surveys like these.
Furthermore, we do not really know what is the view in those papers that are not making a statement to one or another direction in their abstract.
However, my bet is that more often than not, in those papers AGW is taken as a basic and accepted assumption that does not need to be highlighted in abstract. But I can be wrong.
And these and other sources of error and ambiguity have been put forward and addressed in the paper itself.
In any case, the precise numbers are not that important. It does not matter whether it is 85%, 90%, 97% or 99%. It all boils down to a message: There is no real debate in climate science. AGW is real, not a hoax.
And now that we have got that clear, next step would be to agree what to do about it without wasting time on debating with merchants of doubt.
[3] ,

Wednesday, July 10, 2013

Ernst Beck and the high global CO2 levels between 1800 and 1950 - highly implausible

Googling the words "Ernst Beck CO2 measurement" brings quite a few hits referring to the work of the late Ernst Beck from Germany who investigated hundreds of old CO2 measurements from early 1800s onwards. [1],[2] 

Most of the hits come from "climate skeptic" sites since  his conclusion was that climate science has on purpose omitted the results of these studies so that the theory of man made climate change would hold.

However, his results have considerable issues that have not yet been answered, like

1) The variation of CO2 levels stopped as soon as modern measurements started in the end of 1950s. After that they have consistently increased and now at 400 ppm level. If the variations reported by Beck were real this surely would have continued after late 1950s as well.

2) The huge CO2 concentration variations reported up to the end of 1950s would have require enormous flows of CO2 release and subsequent capture within short period of time. However, there has been no evidence of this having taken place.

But, if we accept that the samples analysed in these earlier experiments reflect more of a local inland background CO2 [3],[4] than global background, everything starts to make sense and fits together. Environment itself and height from which samples  are drawn has big influence to the results and it is quite understandable that these old results show such impacts and that these show big variations.

Personally I find this latter explanation far more plausible than the story line of  Beck's site amplified by WUWT, Joanna Nova, Tim Ball, Heartland Institute and others essentially involving a global conspiracy of  climate scientists to distort data spanning several decades and joined by IPCC report after report. [4], [5], [6].


Tuesday, July 9, 2013

About this blog

This blog is for sharing and commenting things for which I do not find a natural home elsewhere..