R QUIRK has treated Gazette readers to a rant, full of opinions, errors, and some truths (Letters, February 20, 'How can Greta be so precise?').

A response is required. To take the points in turn:

It is true that steel production currently requires coking coal, and in principle there is no reason to deny West Cumbrians the opportunity to provide it.

But the manufacturers to whom it is supplied should guarantee the CO2 produced is captured and stored, so as not to increase atmospheric levels.

“Greens” are attacked for wanting oil to remain in the ground, otherwise where would we get lubricating oil? This is to confuse the use of oil for lubrication (less than one per cent of annual production, with little conversion to CO2) with its use as a fuel, which contributes to human-made climate change. So, oil drilling for lubricants is OK, but so is the Greens’ case against oil as a fuel.

An aside about the damage that palm oil production is doing to the Brazilian rainforest is bizarre, given Brazil produces hardly any palm oil (0.6 per cent of the annual global production).

Equally odd, but actually rather telling, is the complaint about protesters digging up turf. We are asked by Mr Quirk: “What does grass do - soaks up CO2 and gives out oxygen.” The admission that soaking up CO2 is useful is interesting (see the last point below).

Then Greta Thunberg is attacked. Mr Quirk says she claims irreversible climate change will occur in 10 years 252 days and 10 hours. This is an unworthy attempt to impugn this brave young woman’s contribution to the climate change debate.

Of course she claims no such precision. She was quoting the IPCC [Intergovernmental Panel on Climate Change] report, written by climate experts, that the global atmosphere cannot take much more CO2 before significant thresholds are reached, with effects that cannot be reversed.

When she drew attention to the IPCC prediction (some time in 2019), this maximum amount of CO2 would have been reached in about 11 years, at present emission rates. This is serious.

Finally Mr Quirk claims global warming is due to cyclical variations of the Earth’s orbit. It is quite true these cycles have profound effects on the Earth’s climate, affecting the solar energy flux and causing the onset and decline of ice ages. But it is also true that atmospheric CO2 and associated water vapour cause the greenhouse effect, by which heat radiated from the Earth’s surface is trapped in the atmosphere.

Natural atmospheric CO2 raises the temperature by about 15°C, making life as we know it possible. By adding to the natural amount (a 50 per cent increase since 1850), humans are warming the planet. This is dangerous. Nobody can deny it.

Ed Tipping