Though it does not actually say so, the report of the Committee on Climate Change (Report, 12 July) is a salutary reminder that a capitalist economy based on infinite economic growth, as expressed in terms of consumption-led GDP, is unsustainable and, if allowed to continue in its present form, will ultimately devastate the entire planet. Moreover, unless we cease using fossil fuels for energy and replace them with renewables at the earliest possible opportunity, the voluntary agreement reached at last year’s COP 21 climate summit to limit increases in global temperatures to less than 2C will be little more than hot air.

For an energy union like the GMB with thousands of members in the gas industry, the priority must be to establish a viable, UK-based, publicly owned renewable energy industry, thus enabling a just transition for those whose jobs will cease to exist in the coming decades. For this to happen, the vested interests of the privately owned energy monopolies have to be challenged, a point eloquently made by climate activist Naomi Klein at a packed meeting during COP 21 in Paris, organised by the Trade Unions for Energy Democracy network, which GMB supports.

Sharing the platform was Jeremy Corbyn, the only senior British politician who understood that the issue of climate change and global warming demanded his presence at the event. Whatever his detractors in the parliamentary Labour party may say about him, he realises that this global emergency transcends party politics and ideological divisions. They would do well to follow his example and stop playing the busted fiddle of capitalism while home burns.

Bert Schouwenburg

International officer, GMB

• The Committee on Climate Change gives the government a warning that global warming could reduce the UK agricultural industry’s ability to maintain its present levels of food production. One of the reasons why the common agricultural policy was created after the last war, was because far-sighted European politicians were desperately worried about European starvation at that time. Their aim of European food self-sufficiency has been achieved. Meanwhile, despite the UK’s high levels of agricultural production, we still have to import 40% of our food. But there has been no need to worry as we are part of an organisation that can easily feed itself.

If we had been told about these worries of declining UK food production, caused by climate change, during the Brexit referendum, who in their right mind would have voted to leave?

David Lucas

Bath

• Observations of accelerated decline in Arctic sea ice suggest that within a few years the Arctic Ocean could be virtually free of sea ice at the end of each summer (Arctic sea ice crashes to record low for June, 7 July). This “blue ocean” condition signifies a huge loss in sunlight reflection and cooling capability which has hitherto kept both the Greenland ice sheet and permafrost areas frozen and stabilised climate in the northern hemisphere. Melting of the ice sheet threatens metres of sea level rise; melting of permafrost threatens vast emissions of greenhouse gases. Climate chaos threatens multiple crop failures in the breadbasket areas where the bulk of crops are grown to feed the world. Famine would exacerbate conflict, already apparent in the Middle East and North Africa, with millions of victims attempting migration to avoid starvation or being killed.

The government claims that blue ocean conditions in the Arctic could occur, at earliest, by 2050. But the climate models which they persist in using have an abysmal track record, consistently predicting a retreat of sea ice many times slower than actually observed. Thus the government has engendered a false sense of security. The danger from blue ocean conditions is not appreciated. No precautions have been taken. And the possibility of preventing the ocean getting into such a state has been summarily dismissed with the comment “intervention would be premature”. Yet if governments collaborated and intervened quickly to cool the Arctic, a huge threat to humanity could be avoided.

John Nissen

Chair of the Arctic Methane Emergency Group

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