I recently saw a cartoon that has uncomfortably embedded itself in my brain: it shows a relatively small tidal wave that is the pandemic, followed by a bigger tidal wave that is the recession, and a still bigger one that is the climate crisis. The only fault with the cartoon is that the tidal wave of climate change will not pass as the others will. Another cartoon showed the world boxing with the pandemic while a boxer twice the size of either—the climate crisis—waits to enter the ring.

Humans are good at responding to immediate threats and hopeless at responding to long term threats. We have known about climate change for four decades, but, as time for an effective response runs out, global emissions of greenhouse gases were increasing by about 7% a year when they needed to decrease by 7% a year. The almost complete shut down of the world economy means that emissions are likely to fall by about 7-8% in 2020. This is good news, but it’s also bad news in that it illustrates the scale of change necessary to achieve the reductions that are essential.

Major events like the pandemic and world wars are usually times of change. As has been said many times, changes that took years can happen in hours, and there is a sense of everything going fluid. We are in that fluid stage, and now is the time to be thinking about how we can create and embed changes that will lead to a healthier, lower carbon economy. That’s why the UK Health Alliance (which I chair) has produced  six principles for a healthy and green recovery and five priorities for action. In producing the document we have tried to steer a middle way between making motherhood statements and straying beyond where we can speak with authority.

We have written to the prime minister, the leaders of the other political parties, the leaders of the devolved nations, regional leaders, and other senior politicians urging them to follow these principles and implement the actions. You might join the advocacy by writing to your member of parliament, talking to friends, and using social media. The trust in health professionals has always been high, but is now higher than ever.

Our call to the nation’s leaders come at the same time as some 200 business leaders, including the chief executive of Heathrow airport and the UK country boss of BP, have written to the prime minister calling for a green recovery for the economy. Their letter says: “A wide range of input, from academic experts to city leaders to official advice, has shown measures that cut greenhouse gas emissions and stimulate the economy have the potential to be more effective in supporting jobs and economic growth while also supporting our long term climate goals and delivering better outcomes in other key areas of public interest, such as public health and wellbeing.”

The principles should be uncontroversial, but there is likely to be mass unemployment that will lead to some calls to create jobs fast, no matter how much they might hasten the climate crisis. Governments will need support to resist such calls.

The first principle is that the recovery should prioritise the health of the people and the planet. We know that what is good for people—lots of walking and cycling, limited use of motorised transport, and eating a largely plant-based diet—is also good for the environment. Many people who have never cycled before have started cycling during the pandemic, and working from home has dramatically reduced the need to drive. These changes should be preserved, but every economic and business decision should include consideration of the effect on the environment and health.

Another principle is that the recovery should be informed by science. During the pandemic scientists have come to the fore, and politicians have boasted of how they are following the science. Science alone cannot make decisions, and politicians should not be allowed to hide behind science or attribute blame to scientists when things go wrong; but science is as important in responding to the climate crisis as it is in responding to the pandemic. When it comes to decisions about the economy, health, and climate, scientists have not been central to decision making, but we argue that they must be.

As was to be expected, the pandemic has cruelly exposed inequalities. Black and ethnic minorities and poorer people have suffered more, and the same inequalities are applicable with climate change. Rich countries and the rich within countries have much higher carbon footprints than poorer countries and poorer people, and yet the poor suffer the consequences more. The pandemic has heightened concern about inequalities, and a healthy recovery offers an opportunity to reduce inequalities.

A final principle is that recovery is everybody’s business. It’s sadly true that no amount of recycling and actions by individuals to reduce carbon consumption will be adequate to avert the climate crisis if governments and global organisations don’t lead, but this should not be an excuse for individuals to fail to make changes in their own life. “Live the change you want to see,” said somebody, possibly Gandhi. The UKHACC plans a campaign to increase carbon literacy among health professionals, but there are many simple actions you can take to reduce your carbon footprint. The members of the Alliance, mostly royal colleges, are also taking actions to reduce their carbon footprint, and the Alliance is working with the NHS on its programme to achieve net-zero carbon emissions as soon as possible.

Climate change is killing people and causing suffering now, but we still have a chance to reduce the potentially devastating impact climate change. “Never waste a crisis,” the saying goes, and we must not waste the opportunity presented by the pandemic to build a healthy and green recovery.

Richard Smith was the editor of The BMJ until 2004.

Competing interest: RS is an unpaid chair of the UK Health Alliance on Climate Change. The BMJ and the BMA are both members of the Alliance.