Apologies in advance for a long answer:
For me this is Politics vs Science. I don't feel these two things are good partners.
The Global Pause, as highlighted by
@Jim Tolmie's Underpants , is a good place to start. The Global Pause is the apparent flattening of changes in average global temperatures in the period 1998 to 2013, much to the delight of some and shock of others, indicating (on face value) that anthropogenic forcing has not had an effect on global warming as of late:
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1. Tiny bit increase here 2. Pretty much no change in this interpretation
Nature ran a
couple of specials on the hiatus and many media publications have run with the story and even, despite what some say about them, the IPCC did acknowledge and include the term 'hiatus' in their
5th Assessment Report of 2014. (more on IPCC in a bit).
These are
some of my issues with the global pause graphs:
- A pause on a short term scale such as this is not a fair comparison to multi-decadal climate science
- decade scale trends dominated by natural fluctuation (Markotze & Foster, 2015 and others) do not provide grounds for revising global opinion on global multidecadal temperature trends (Risbey, 2015)
- There is no real evidence that these graphs are statistically significant. Foster and Rahmstorf (2010) statistically analysed 5 quasi-global temperature datasets (GISS, NCDC, RSS, CRU and UAH) and found no statistical evidence for slowdown (in this period).
- a lack of bias correction
- There are no error bars, no confidence margins, no studies of relative error
- The RSS data is reliant on the old NOAA-15 satellite which has a decaying orbit to which corrections are applied using a model.
My issues with using these graphs as argument deciding statements of truth:
- They are simplistic and do not attempt to acknowledge any short comings
- They use one, possibly faulty/out of date dataset (instead of scientific calibration of up to 5)
- They badly misrepresent a climate science (studying short term temperature fluctuations against a long term science)
- People use this data as gospel truth as they think it is 'raw' and true, forgetting it has been corrected, as ALL satellite data is corrected, but also corrected due to ageing technologies. and this is NOAA data who appear to be a bad-apple for a lot of folk.
- There is no smoothing of data noise
- @lazza said it perfectly that anyone can throw a graph of anything at someone and purport it to tell the truth. in climate science this rings very true.
Possible explanations for the pause:
- As mentioned, natural events such as earthquakes, el nino & la nina and solar variations.(Markotze & Foster, 2015 and others)
- zooming in to a 'useful' period of time
- huge build ups of energy in oceans;
This is a good place to bring in good old Piers Corbyn:
Piers is an interesting and clever man, but his insistence on a scientifically shaky short-term dataset is worrying and, as a meteorologist, fails to highlight recent natural phenomena that influence climate so strongly. He has not had much peer-reviewed work, is not a climate scientist, and crucially (for a scientist) he will not open his methods for weather prediction for scientific scrutiny (bad form in the science world!). It's a no from me for Piers Corbyn.
And next to
@Jim Tolmie's Underpants assertions using the 1975 NAS graph:
It's an interesting one to bring up, written by Peter Gwynne it caused a stir at the time and is still used to this day. However, a cover up and a scam i would say it is not;
Peter Gwynne
retracted his article and methods used therein for the above graph in December 2014, after agreeing the weight of evidence was not properly addressed. Whether you think he was originally dodgy and has come clean or originally was clean and has been bought or has, like a good science writer, had a decent stab and then manfully retracted his ideas, is up to you :)
And so to the long term stuff:
long term trends do show increases, couple with the recent cooling/pause, the cooling pause is included.
NASA MetOffice
i think there are some fairly wild claims there, but youre welcome to them. There is a wealth of scientific papers out there that explain why you must correct models; performing multivariate regression and principle component analysis allow you to remove natural phenomena such as earthquakes which are helpful to neither serious pro or anti anthropogenic climate change scientists. have a google about.
Main Conclusion:
The variables and the science are baffling. everything is highly interconnected and to say it is simply "this" or "that" is just not helpful or even remotely near the truth. 1000s of scientists are still teasing out the effects of the oceans, the sun, clouds, surface temps, troposphere temps, effects of satellite orbits, mathematical models, model forcing, natural events, greenhouse gases, aerosols, particulate matter, etc ETC!!!! the list goes on and on and on....... How do we explain global cooling is producing the hottest years on record? who knows.
Sadly that doesnt get us to an answer. Someone earlier said that we will never get an answer in our lifetime so we can say what we like. Well, for the purpose of scientific discovery i hope science continues to build and be as rigorous and open to criticism and interrogation to help find an answer. Im not going to tell you what I personally think is currently happening though.
The Politics:
oh the politics. For all the arguments of IPCC corruption, government control via climate change and profiteering on carbon credit schemes, there are counter claims for hydro-carbon funded skeptics, deliberate nobbling of climate change science and capitalist driven denial empires.
How someone can confidently claim one evil exists and that the other does not is beyond me. However, i would like to say there are very believable kernels of truth in
both.
The IPCC, as alluded to by other posters, is a bit political (but to say it's not scientific at all is going a bit far). I have no doubt in my mind that governments/corporations (governmental-industrial nexuses) across the world are attempting to manipulate and profit from this, using what they see to be the weight of evidence (in favour of anthro climate change) to drive their own agendas and perhaps, to a degree, control development in the developing world. Carbon trading is madness and a see through scam. Yet how can governments work towards reducing emissions, particularly of methane, nitrogen oxides, PM10 and sulfur hexafluorides, and not appear all controlling? And how can people confidently say the petro-chemical industry, which face it has a little bit of a dubious working practice, has no say in climate change denial? two sides of a very big coin.
i like to speculate on these things but prefer the science. though i see it, in everyday media and government speeches and policies, there are agendas, as plain as the nose on your face, they exist, with very little scientific scrutiny.
What's it all about?
who knows? i certainly don't. And many a good scientist will/should not claim to either. The predictions and claims are made by evidence, backed up by many peer reviewed journals and statistical studies. This goes for both pro and anti anthropogenic climate change. From my experience it would seem the majority of sound peer-reviewed science is towards the existence of global warming and a proportion of that towards anthropogenic climate change. Why this is, i will not dare to say :)
I hope someone got something out of these ramblings.
