The climate will have the final word - but this word may be severely and irreversibly damaging
IN HIS letter on Tuesday 3 September, Mr Domaille expresses the view that articles on the opinion page of the Guernsey Press should not be subject to censorship. This is with reference to recent articles on climate change and whether it is due to human activity. He accepts that global warming is happening, but considers it debatable whether it is due to man-made or natural causes. Unlike the other authors of opinion pieces or letters dismissing the role of human activity in causing the warming of our climate, several of which have appeared recently in the Guernsey Press, he provides us with an explanation of his position.
He states correctly that CO2 levels have been increasing since the 19th century. What he fails to point out is that CO2 levels increased rather slowly from 1800 to 1950, but much more rapidly in recent years. Since the 1950s, the levels of CO2 in the atmosphere have increased more than eight times faster than in the preceding 150 years, and yearly emissions are still increasing.
In a similar manner, he claims that global mean temperatures increased erratically by 1 degree Celsius between 1800 and 2000. As with CO2 emissions, he fails to point out that until the 1950s and 1960s global temperatures rose erratically and slowly, but since the 1960s temperatures have risen much more rapidly, some eight times faster since the 1960s than in the previous eight decades. This rise in global temperature since the 1960s has been accelerating, with the last five years being the five hottest in the published records (NOAA and NASA of the US and the Hadley Centre of the UK).
The recent accelerated rise in CO2 levels since the 1950s has thus coincided closely with the accelerated rise in global temperatures, and the IPCC (the UN body responsible for establishing international consensus on climate change) in its most recent report in 2014 states categorically that it is ‘extremely likely that rising greenhouse gas emissions, in particular CO2, have been the dominant cause of the observed warming since the mid 20th century’. In their 2014 report, the IPCC also examined the role of natural causes in recent global warming, and conclude that natural causes have had virtually no effect. Mr Domaille quotes the IPCC as saying in a report that ‘the long-term prediction of future climate states is not possible’. He doesn’t reference the quotation, but in its recent 2014 report the IPCC states exactly the opposite, namely that ‘multiple lines of evidence indicate a strong and almost linear relationship between cumulative CO2 emissions and projected temperature change to the year 2100.’ He also states that the scenario of burning fossil fuels leads to catastrophe isn’t part of the IPCC’s assertions. What the IPCC says in its 2014 report is that ‘continued emissions of greenhouse gases will cause further warming and long lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems’. The IPCC is part of the UN, and its use of language is cautious and moderate. For it to describe future impacts as severe, pervasive and irreversible is as close to warning of a future catastrophe as it is likely to get.
The suggestion Mr Domaille makes that the IPCC reports provide grounds for his climate scepticism is wrong on every point. But at least by sharing the grounds for his climate scepticism with your readers, one is able to see that these grounds are simply wrong. Those others who, without giving their reasons, have expressed in your columns a belief that ‘natural causes’ are the reason for the changing climate, in the face of an overwhelming scientific consensus to the contrary, lose credibility for other unsubstantiated opinions they may express. It can seem as though some seek to hide behind indefensible positions to avoid accepting a responsibility that we all should share to mitigate the impending climate crisis.
Finally, Mr Domaille asks, ‘why all the panic and hysteria?’ It’s not panic and hysteria to be deeply concerned by the warnings of virtually all climate scientists that without rapid and decisive action to reduce greenhouse gas emissions, particularly CO2, the world is facing severe, pervasive and irreversible impacts for people and ecosystems, which will only get worse if adequate mitigation is not implemented soon. Anger, also, particularly among younger generations whose future is being deeply jeopardised by lack of effective and timely action. As Mr Domaille says, the climate will have the final word, but unless we act rapidly and at the scale required, this word may be severely and irreversibly damaging.
PROFESSOR NICHOLAS DAY
Route de la Lague,
St Pierre du Bois.