Our unsustainable lifestyles and commitment to perpetual economic growth have become the major drivers of climate change and loss of biodiversity on Earth (Only rebellion will prevent an ecological apocalypse, 15 April). Our politicians fail to grasp the scale and urgency of the risk humanity faces. The UK signed up to the UN's sustainable development goals (SDGs) in 2015, but has yet to develop a coherent and rigorous national plan for their domestic and international implementation.
Encouragingly, the SDGs form a new roadmap for our future that in principle aligns the economy with the Earth's life support systems. Yet, a recent report by the Stockholm Resilience Centre shows that attempting to achieve the socioeconomic goals using conventional growth policies would make it virtually impossible to reduce the speed of global warming and environmental degradation.
The research team tested three other scenarios, and the only one that met all goals implemented systemic transformational change. A key element was reducing inequality by a redistribution of wealth, work and income, including ensuring that the 10% richest people take no more that 40% of the income.
We clearly have an unprecedented and immense challenge before us, with little choice but to engage as a mass movement to create a system-wide transformation in our politics and our economy.
Stephen Martin Visiting professor, University of the West of England
Stephen Sterling Emeritus professor of sustainability education, Plymouth University
• Both Extinction Rebellion and the climate strikes are reminders that we need to rebuild our societies now if we are to avoid them facing climate collapse in the near future. But both initiatives need to avoid the fate of the Occupy movement, which had huge support 10 years ago but disintegrated because of a lack of precise demands and concrete policy goals.
Fortunately, many such policies already exist. The organisation I founded, the World Future Council, has identified the best policy solutions available in countries, regions and cities worldwide. British Columbia has a carbon tax. Maryland, US, has obligatory environmental literacy education. Rwanda has a successful reforestation policy. Japan has an effective energy conservation law. Costa Rica has an exemplary biodiversity law.
These provide starting points. But the UK has gone in the opposite way: 10 years ago the WFC helped MPs introduce feed-in tariff legislation (originating in Germany) to speed up the production of renewable energy. But the coalition government hastened to emasculate it. As many proposals are rejected over cost, a key recommendation is the adaptation of quantitative easing to fund the energy transition.
One WFC proposal is for central banks to buy fossil fuel "stranded assets" on condition the money paid is invested in renewables. How this can be done sustainably is explained in our study "Unlocking the trillions". As central banks cannot go bankrupt in their own currency, they can also buy - and add to their reserves - long-term and low- or zero-interest bonds to kickstart the required emergency reforms in poor countries.
Jakob von Uexkull
Founder, World Future Council
• Larry Elliott is informative on a subject that matters, as usual (Threadneedle Street's timely warning for banks and insurers: take climate change seriously, 16 April). But insurers have taken it seriously since at least 2009, when a representative of Munich Re wrote: "Climate change probably already accounts for a significant share of economic losses from weather-related natural catastrophes in the period since 1980, which totalled $1.6tn (in original values).
"In the light of these facts, it is disappointing no breakthrough was achieved at the Copenhagen climate summit in December 2009. At Munich Re, we look closely at a multitude of risks and how best to handle them. Risks that change in the course of time are especially hazardous. Climate change is just such a risk of change."
But even the premium increases 10 years later don't appear to have cut emissions sufficiently. So the Bank of England must convince the government to take more effective action. For example, as in the second world war, introduce rationing of any production of greenhouse gases.
• Are US college courses teaching how not to be duped by bullshit really necessary ('Calling bullshit': the college class on how not to be duped by the news, theguardian.com, 17 April)? If students haven't developed their critical thinking faculty by the time they get to college, they are probably lost to the agencies of disinformation and manipulation.
In Britain, it is obvious that our education system, designed as it is to provide compliant labour to increase the wealth of a few, has failed when its cities are filled with humanity-saving, peaceful demonstrators. It is inspirational to observe their ability to recognise what is truly important and disregard the odium of passersby - normal people going about their business, in many cases to finance or produce goods harmful to humanity and the natural world. These protesters are the freethinkers who have escaped the bullshit net.
• In This Changes Everything, Naomi Klein defines one legacy of the free market: "In virtually every country the political class accepts the premise that it is not the place of government to tell large corporations what they can and cannot do, even when public health and welfare - indeed the habitability of our shared home - are clearly at stake." In the streets, yes, but in the ballot box we bring about the inevitable and dismiss our free-market political class. We build a new system.
• I admire Ben Smoke's action at Stansted (Journal, 16 April), but disagree with him about arrest, though agree about not glorifying it and being clear about the consequences.
I am a Quaker, a psychotherapist member of the Climate Psychology Alliance, which aims to support activists therapeutically, and a member of Extinction Rebellion. What we need is a mass movement with arrest as a possible and necessary part of it. When thousands join us in solidarity and put this issue before everything else, the state will have to listen and take action.
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