RECENT letters in The Herald denying the threat of climate chaos show a shocking disregard for possibly disastrous consequences if we continue burning fossil fuels at present rates.

Rev Dr John Cameron dismisses Greta Thunberg’s speech to the UN calling for real action now as teenage scare-mongering (letters, 2 Oct) even though what she says is based on Intergovernmental Panel on Climate Change (IPCC) reports by UN scientists.

Likewise, David Stubley claims (letters, October 3) that climate scientists are only interested in their careers and follow the IPCC line out of expediency. The only evidence that Stubley offers for this sweeping condemnation is that someone told him so. What a pathetic basis for such a serious charge.

In fact, climate science has been accumulating knowledge and explanatory power since the mid-nineteenth century. Progress has been slow and it has required dedication and hard work by many scientists all over the world.

In his book, ‘The Discovery of Global Warming’, Prof Spencer Weart charts the history of climate science and shows how scientists gradually came to realise that greenhouse gas emissions, especially CO2 from burning fossil fuels, are injecting more energy in the form of heat into the climate system and thus destabilising it.

Evidence for climate change is seen across the world. The increasing temperature of oceans and atmosphere has many effects.

In Arctic circle lands the perma-frost is melting. Corals are dying on the Great Barrier Reef. Photographs show how the Muir glacier in Alaska has lost millions of tons of ice in the last fifty years. Glaciers all over the world are melting. Likewise, Arctic summer sea ice grows smaller every year. Satellite imagery to demonstrate sea ice shrinkage and other global heating effects can be found on the NASA website.

The Earth is about 8,000 miles in diameter and the atmosphere is about 60 miles deep. The atmosphere of planet Earth is only a thin skin, but we are completely dependent upon it for the air we breathe and the moderate amounts of rain and sun which nourish our food.

But we have altered the composition of the atmosphere and damaged our climate system. Therein lies the threat of climate chaos. Constant hurricanes and torrential rain would destroy our agriculture and our way of life, as they have done for millions of people in the Caribbean.

In other places, extreme temperatures and scorching winds can bring droughts and death to many. Only recently we have discovered that Planet Mars used to have surface water, but not any more. The warning is plain to see.

It is not alarmist to say that humankind faces a grave danger in the form of climate chaos. The threat is towering before us like the iceberg that sank the Titanic. Drastic action is needed to change course. We must cut our CO2 emissions to the bare minimum. Burning oil, coal and gas has to stop. We must eat less meat and instead eat more local produce.

The days of cheap flights and casual tourism are over. Altogether it means a complete overhaul of our way of life, but the hardship which that causes will be trivial compared to the devastation that we shall have avoided.

Les Reid, Edinburgh.

OUR politicians, both north and south of the border, are justifiably pilloried for multiple errors of commission and omission but, in one field at least, fighting climate change, they are doing all they can and involving us taxpayers to the hilt.

That field is decarbonisation, which will cost us all trillions of pounds, damage our industrial competitiveness, impair energy supplies for homes, hospitals and factories and, if the Greens get their way, will even make us vegetarians.

Why, then, do Extinction Rebellion, Greta Thunberg and the like demand intensified efforts aiming to offset global warming? Do they not know that greenhouse gases from the UK are negligible at 0.3 per cent of one per cent of the planet’s total, Scotland’s a tenth of that? The great bulk of the world’s CO2 is released by non-complying nations - China, India, USA, Russia and many more.

By not “investing” resources in the fight against climate change these nations have much more money to maintain vital spending on health and welfare, education, infrastructure and defence. Arguably, wasting resources on a futile fight is a more rational political and economic accusation than is complaining that not enough is being spent.

Dr CharlesWardrop, Perth.

FIFTY years from now, when the world will have taken a considerable turn for the worse, it would be interesting to ask the children of modern-day climate-change deniers how they feel about their parents’ refusal to take the issue seriously.

S Reid, Glasgow