There is evidence behind theories

John Lillburne’s letter (‘No evidence in climate claims’, October 5, 2017) is a perfect illustration of Brandolini’s law: that the amount of energy needed to refute rubbish is vastly larger than to produce it. Nonetheless, as he’s accused me of being ‘alarmist’ about climate change, I will briefly address three of the points he raises.

Firstly, Mr Lillburne writes that ‘claims about man-made, CO2-driven climate change’ are ‘unscientific’ and ‘unsubtantiated’. In reality there is now a mountain of evidence – and near-unanimity among climate experts – that humans are causing global warming.

For example, a 2013 survey of over 12,000 peer-reviewed climate science papers found 97 per cent consensus about this. It is also the position of the Academies of Science of at least 80 countries.

Secondly, Mr Lillburne challenges me to ‘give a concentration in parts per million of C02 that represents a tipping point, that will cause the planet to become a burning cauldron’, writing that ‘we could then evaluate this figure against historical records to see how the planet was fairing at the time of this named concentration.’

Hyperbolic words about burning cauldrons aside, Mr Lillburne makes a basic misunderstanding about CO2, namely that while an important factor in determining global temperatures, CO2 is not the sole factor.

There have been periods hundreds of millions years ago when CO2 levels were much higher than today and yet the planet experienced widespread regions of glaciation. However, there is no contradiction here as the sun’s output was lower.

Thirdly, Mr Lillburne asks me to ‘name an approximate date when, if we continue to produce C02 at the present rate, the planet will fall into the fiery furnace’.

More hyperbole (‘fiery furnace’) doesn’t really help Mr Lillburne’s case. In fact, scientists have calculated – and the UK Government accepts – that roughly three-quarters of known fossil fuels (oil, coal and gas) will have to be left in the ground unburnt if we are to have even a 50 per cent chance of limiting the global temperature rise by 2100 to two degrees Celsius.

Such a temperature rise would be enough to make every European summer as hot as 2003, when 30,000 people died from heatstroke, and would also be enough to cause the eventual complete melting of the Greenland ice sheet, raising global sea levels by seven metres.

This is one of the reasons it makes no sense for the East Sussex Pension Fund to continue to invest £150m of local people’s pension monies in fossil fuel companies

We urge those of your readers who live in the real world – as opposed to Mr Lillburne’s imaginary one – to add their voice to the growing call for the county council to ditch these dirty and financially risky investments: http://tinyurl.com/divestescc.