John Harwood outlines the dilemmas countries face, while Neil Sinclair says adults should be doing more than 16-year-olds to tackle the problem. Plus Steve Brace on studying geography and Alan Frost with an idea for cutting pollution

Joyce Quin is right to draw attention to the links between trade agreements and responding to the climate crisis (Letters, 7 December). But the link goes way beyond the advantages of trading closer rather than more distantly.

As the climate emergency grows more serious, the world’s nations will at last start having to make real choices about whether to respond seriously to the challenge. Those that do will be faced with the urgent dilemma of how to deal with those that don’t.

Lord Stern’s hope that all states would be amenable to rational analysis and persuasion seems to have proved overoptimistic. Thus the only real option (excluding military action for obvious reasons) will be to refuse to trade with those states that are unwilling to face their responsibilities, except in those sectors that are not damaging to the climate.

There is some logic to this in that the economic policies and models of the states that are most hostile to effective emergency measures are also to a large extent those contributing most to climate change. Seriously damaging these economies would be brutal – but the alternative is even worse. The issue for the UK is where are we going to be when this choice has to be made.

John Harwood

Woodstock, Oxfordshire

• Adults need to stop telling Greta Thunberg how inspirational they find her and how wonderful she is (Thunberg, 16, is youngest ever recipient of Time person of the year, 12 December) and start apologising for not having done more themselves about climate change over the past three decades.

Neil Sinclair

Edinburgh

• The teachers who have left the classroom for Extinction Rebellion (‘Schools feed the problem’: Why Mr Jones rebelled against climate emergency inaction, 10 December) may feel that schools fail to teach about the ecological emergency, and they voice concerns about a lack of progress in relation to social mobility and climate change.

However, they should be heartened to know that geography – the GCSE subject that teaches about climate change, ecosystems, biodiversity and resource management – is gaining more and more traction with young people from all backgrounds. Since 2010 this subject has experienced year-on-year growth, which has come disproportionately from disadvantaged pupils, black, Asian and minority ethnic pupils and those studying in comprehensive schools.

Studying geography helps young people better understand the interdependencies between people, the environment and places – be they at the local or global scale. In this way, it is a subject that helps young people, regardless of background, discover the truth about our world and the environmental challenges we face.

Steve Brace

Head of education and outdoor learning, Royal Geographical Society (with IBG)

• Re your article (Climate threat from Europe’s shipping emissions revealed, 10 December), a couple of months ago villagers of Shotley, a Suffolk village across the River Orwell from Felixstowe container port, questioned why the village was placed in a list of the top 10 unhealthiest places to live in the UK, with air pollution among the factors taken into consideration.

I presume a sizable portion of pollution affecting Shotley is produced while ships run their oil-burning generators continuously while berthed. Would one way of reducing pollution be to provide quayside stations to which each ship has to connect a cable to draw mains electricity?

The North Sea off the Suffolk and Essex coast is home to wind generation, with more to come. The more environmentally aware and cost-conscious shipping operators are using liquefied natural gas instead of oil for propulsion. A small number are trialling wind turbines mounted on deck for secondary propulsion. Why not stop using oil-generated power while berthed?

Alan Frost

Harwich, Essex

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