VN–klimaatpanel schuift op richting klimaatsceptici

Een kwestie van begrijpend lezen!

President Obama zei het in zijn 'State of the Union': 'The debate is settled. Climate change is a fact'.

Een gezaghebbende uitspraak? Nee dus! Het tweede is waar, het eerste niet.

Het VN–klimaatpanel (IPCC) wordt – ten onrechte – gezien als de gouden standaard van de klimaatwetenschap. Voor politici gelden zijn rapporten als de bijbel. Die rapporten zijn ondoorgrondelijk voor het merendeel van de politici, de media en het publiek. Daarom is er een samenvatting voor beleidsmakers ('Summary for Policymakers' = SPM). Maar ook deze blijkt moeilijk te lezen. Want wat de politiek er in meent te lezen, staat er in werkelijkheid niet in. 

Het IPCC erkent – zij het ietwat verborgen in de tekst – dat de wetenschap er helemaal niet uit is. Een recente exegese van John McLean kan de lezer helpen om te begrijpen wat er werkelijk staat.

Onder de titel, 'Parsing the IPCC’s Piffle', schreef hij onlangs in Quadrant:

Warmist politicians and professional alarmists who tell us man-made global warming is an increasing problem are forever repeating the mantra that "the science is settled". Given the acknowledged flaws and discordant findings of their cited models, that confidence reflects either ignorance or deceit. There is no other explanation

Politicians and various activist organisations are fond of telling us that there is no doubt that man-made global warming is an ever-increasing problem. If you ask them for the source of their information they will almost certainly direct you to the assessment reports by the UN’s Intergovernmental Panel on Climate Change (IPCC). Maybe you should ask them if they have read the latest IPCC report, because it tells a very different story.

All politicians should at least have read the Summary for Policymakers (SPM), the document specifically tailored for them by scientists and then revised by government representatives. Being ignorant of the contents of the SPM would be major failing of any politician. IPCC reports use language that the lay-person might find difficult to understand, and in fact some government complained that the wording of the SPM was too complex, so where necessary I’ll try to explain what the statements mean.

McLean analyseert vervolgens een aantal passages uit de SPM. Hij concludeert:

Let me summarise all this. The first quote shows that temperatures were basically flat for the 15 years from 1998 to 2012, when the IPCC report was written. The second quote shows that 97% of model executions wrongly predicted greater warming than occurred over that period. The third quote admits that some (!) climate models exaggerate the influence of greenhouse gases on temperature. The fourth concedes that climate models differ in how they mimic both natural and man-made climate forces. The final quote tells us that climate models are not only used for predictions, but also for estimating the magnitude of human influences on temperature (which must mean that failures in prediction are accompanied by failures in estimating that influence).

If you can find any grounds for a supposed scientific consensus in those statements you’re doing better than me. There’s not even a consensus on how to factor in the influence of greenhouse gases in climate models. The reality is that the IPCC has no clear idea of the magnitude of any human influence on temperature. Its old estimates were based on the output of climate models, but now we see the IPCC admitting that climate models are seriously flawed and over-estimate the influence of greenhouse gases.

Put that with the IPCC’s acknowledgement that there’s been no warming for about 15 years and it’s clear that after 25 years of operation and five assessment reports the IPCC hasn’t achieved much at all, apart from claiming ever-increasing certainty that humans are responsible for most of the warming since 1950, this despite the absence of any credible evidence to support that position.

Politicians and others who try to tell us that man-made global warming is an increasing problem, endlessly repeating the mantra that “the science is settled” are either ignorant or deceitful. Simply put, there are no other explanations.

Aldus John McLean.

Zie verder hier.

Kortom, wat de klimaatsceptici nu al vele jaren beweren, staat nu ook te lezen in de rapporten van het IPCC. Maar waarom blijft dit onopgemerkt in de politiek en de media?

Voor mijn eerdere DDS–bijdragen zie hier.