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Leaders: the urgency is even greater than you think

The intense ‘heat dome’ and rainfall events in North America, Central Europe and China have been overwhelming. German Chancellor Angela Merkel called the scale of flood damage “surreal”. President Xi Jinping labelled “extremely severe” the implications of one year’s rain falling in Henan province over three days.

But no one should consider these as a shock. The events are in line with scientific warnings. Leaders must expect and plan for even greater extremes.

In this appeal, the UK government’s former Chief Scientific Adviser urges leaders and the public to grip the intense reality of what we all now face. Planet earth is passing tipping points faster than expected. In turn this creates additional and unexpected tipping points.

Here Sir David sets out why leaders must help to Reduce, Remove and Repair. He was launching the Climate Change Advisory Group of leading scientists on 24 June 2021.

We need to reach out to everyone and explain that there is a crisis. But if we act quickly we can bring the risks to a manageable level. When I say quickly I mean actions taken in the next five years being critical to the future of our planet’s ability to manage our civilisation.

The biggest challenge we have is reaching out to the public to get an understanding of the nature of this climate crisis. Then reaching out through the public – and the public is a crucial conduit in the process – to the political system of the world. But also to investors, to banks, to public companies, to private companies.

Let me talk about tipping points.

A tipping point is reached as global heating pushes temperatures beyond a critical threshold. There are many tipping points around the world. But they are not easily predictable in a scientific way.

When a tipping point is reached, the follow through is an accelerating process.

Look at Northern Finland. The Arctic Sea ice has been there for so long protecting that region from the sun’s rays during the Polar summer. Now the melting sea ice has left roughly fifty per cent of the Arctic Sea open to sun light.

The net result is temperatures rising frighteningly rapidly, as we have witnessed this summer. In Finland and Northern Russia the temperature over 30 degrees centigrade. That is from minus thirty degrees centigrade several months ago.

These tipping points have global consequences . If we follow through on Greenland ice melting, then sea levels globally will rise. Every bit of ice that melts on land ends up in the oceans. And sea levels could rise to unmanageable levels if this is allowed to continue.

The other important side with tipping points is that one tipping point can set off another tipping point. So this complicates these feedback mechanisms.

We need to focus heavily on managing the processes not only for avoiding tipping points, but to step in and reverse the actions of these tipping points.

When I look at the risks around the world and rising sea levels, South East Asia is at risk in just thirty years of losing four livable areas.

90% of Vietnam is now expected to be flooded once a year by seawater. One flooding with sea water of the Mekong Delta - and the whole of Vietnam is a delta - will mean it is no longer in rice production. This is one of the biggest rice producing countries in the world.

We’re going to see the same in Indonesia with the capital Jakarta under water this year, already. Jakarta is not going to be a livable city in 30 years time.

If all of this continues, and we look across to Bangladesh, you are quite terrified by what you see there. People are being confined to a smaller and smaller area in that part of the world.

So we’re looking at a potential for a very large numbers of climate refugees which I believe would de-stabilize the global economy.

Look at the Amazon rain forest, and the natural deforestation - by which I mean not driven by human beings cutting forests down but by forests dying off due to temperature rises and changes in humidity.

We look at more wildfires occurring, particularly in North America and Australia. These are more wildfires driven by the same impact.

The point is that the planet has already heated by 1.25 degrees centigrade above the pre- industrial level. So when we talk about staying within 1.5 degrees to limit the impacts of climate change we have to say that we are already rolling forward over 1.5. That is even if we were to reduce emissions to zero in a very short period of time, which we won’t do.

So what do we need in terms of actions?

We’ve got the three R’s: Reduce, Remove and Repair.

Reduce means reduce greenhouse gas emissions. And for greenhouse gas I’m including not only carbon dioxide, but also methane. Methane emissions currently are rising faster than before. They are now at a rather frightening level and could be much higher soon.

Secondly, Remove. We need to bring down greenhouse gas levels. And we need to add in methane. If we use carbon dioxide equivalent, then it’s somewhere between 460 and 508 parts per million depending on what figure you use. It’s already too high. We need to bring that level down to 350 parts per million.

That means we have to learn how to remove greenhouse gases from the atmosphere safely. And if possible mimic natural processes and improving the world’s bio systems while we do it.

Finally, the third R is Repair. We are looking at systems such as the Arctic Circle region to see whether we can actually reverse the system that has caused the unfreezing of the ice over the Arctic Sea.

The potentially dark reality we all confront was then described dramatically by Professor Klaus Lackner, director of the Centre for Negative Carbon Emissions, and professor at the School of Sustainable Engineering and Built Environment. He says the urgency for achieving Net Zero must be advanced significantly to well before 2050.

I have always made an analogy. We are in a car going way too fast down a steep mountain road. There’s a sharp curve coming. I think at this point we will hit the guardrail.

So the question is: should we really be carbon neutral by 2035? Of course we should. Because if we aren’t we have to pick up an awful lot of carbon afterwards. The question in my view is we already see some damage. We hit the guardrail or some stones on the way down, and it’s going to get worse.

So we need to be ambitious about it. Whether we really make 2035 is the second question because it’s hard. On the other hand, the question is not should we give up because the challenge is will we roll the car or will be just tear the fender off.

I’m voting for the fender. We need to slow down as fast as we possibly can.

They are brought together in a new book Standing up for a Sustainable World: Voices of Change. It is edited by three of the world’s leading analysts in sustainability and the climate emergency. Here they highlight the personal lessons that all leaders can learn from the stories.

The world has on some key dimensions made extraordinary progress since the end of World War II. Output per head has quadrupled. Poverty, in terms of incomes, has been dramatically reduced. Life expectancy has increased by around 30 years.

However, the extraordinary growth has come at colossal envi ronmental cost. So the world is now in a deeply dangerous position with a very narrow window for action.

Our biodiversity has been brutally damaged. Our oceans have been fundamentally altered and marine life is in great danger. Our forests have been ravaged. Our air and water have been profoundly polluted. And our climate is gravely threatened in ways that could cause immense harm to lives and livelihoods across the world, lasting for centuries.

Our last chance to save the planet as we know it

Time is short. If we fail to act decisively in this decade, the damage to our climate, oceans and biodiversity is likely to be irreversible. This is our last chance to save the planet as we know it.

Here we highlight those who have not only understood those threats but become witness to them. They have confronted them, often at great costs to themselves.

The forces against them are systemic. The individuals or organisations they have to take on are powerful, and often ruthless and malevolent. The most celebrated pronouncement in economics – Adam Smith on the “invisible hand” in 1776 - today sounds desperately outdated. He wrote that by ‘pursuing his own interest he frequently promotes that of society more effectually than when he really intends to promote it’.

Pursuit of profit and power, not respect for nature

Instead of a competitive market where providers meet consumers’ demands, we have at the core of the economy a nexus of dominant firms. Private oligopolistic companies in Western countries. Or state-owned and state-controlled in China. Or cronyist corporates in Russia, Iran and other developing countries. They pursue their own goals of profit and power.

They do this mostly indifferent to the welfare of the people, particularly inimical to their health and the environment within which they live. They feed the exorbitant financial returns expected by shareholders, or by any sort of people in control. They do it by systematically destroying the natural capital – biodiversity, air, water, soil, climate – without which life on earth is doomed to collapse.

Our book brings together inspirational stories and experiences. It is about, and by, those who have seen ways forward to a much better development path for human well-being, security and dignity. They show how we can raise living standards and fight poverty across the world at the same time as creating a much safer and more attractive environment.

Old think is weakening, but not enough yet

Their momentum is building. The old polluting forces are somewhat weakening. But our future is in the balance. We share their voices, vision and hope in order to help to tilt the balance their way.

The evidence on the scale and urgency of the threats is overwhelming. There should be no doubt that we are facing global systems challenges across multiple dimensions that are crucial to our well-being.

There is a flood of scientific warnings illustrated in the following examples.

Scary data

The 2019 Aqueduct Water Risk Atlas published by the Water Resources Institute identifies 17 countries which are home to a quarter of the world’s population. They face ‘extremely high water stress which will be close to day zero conditions when the taps run dry’.

India and Pakistan are among them. Countries and regions like the Yellow River basin depend on dwindling Himalayan or Andean glaciers for their water. They are on the edge, as are the south west United States, Mexico and Central America, as well as countries around the Mediterranean Sea.

This severe water predicament is closely connected to global warming.

The Intergovernmental Panel on Climate Change (IPCC) in 2018 compared 1.5°C and 2°C increases in global mean temperature above pre-industrial levels. It highlighted that the proportion of the global population exposed to severe heat at least once every five years is more than 2.5 times greater. Also, that the proportion of vertebrate and plant species that lose at least half of their bioclimatic range is double.

There is strong evidence that exceeding 2°C will result in large biomes on earth collapsing, such as coral reefs and tropical forests. Going even beyond implies that ‘warming could activate important tipping elements, raising the temperature further to activate other tipping elements in a domino-like cascade that could take the Earth System to even higher temperatures’.

Why we must all contemplate the unbearable

This describes a road to unbearable conditions of life on Earth: “In the absence of migration, one third of the global population is projected to experience a mean annual temperature greater than 29°C. This is currently found in only 0.8% of the Earth’s land surface, mostly concentrated in the Sahara.”

Giant redwoods in Sequoia National Park, California, are already having enough.

They were supposed to live for another 500 to 1,000 years. The combination of drought stress, fire damage and overall warming have made them vulnerable for the first time as far back as we can know to bark beetles infestations. “That’s not how giant sequoias die,” laments Dr Christy Brigham, chief biologist of Sequoia and King’s Canyon National Parks.

A stern health warning was recently formulated by the 2019 Lancet Countdown on health and climate change: “A business-as-usual trajectory will result in a fundamentally altered world. The life of every child born today will be profoundly affected by climate change.”


They are community leaders and organizers of mass protests or of campaigns unveiling pollution, land grabs, deforestation. They are rangers, farmers, teachers, artists. They face land invaders, loggers, poachers, dam builders, mining operators, drug traffickers, corrupt public authorities, death squads.

Defenders live in and around the Amazon, Congo or Southeast Asia forests; in East and Central African savannahs; in various Indian states; in the islands of the Coral Triangle across the Philippines and Indonesia; in Central American villages; in the plains of Dakota, USA; in Queensland, Australia, and so on.

Every year they are murdered by the hundreds. Nevertheless, their numbers are growing. The Guardian newspaper, and in particular Jonathan Watts, who popularised the name Defenders, regularly publishes information about them.


They are active in many places – Australia, Colombia, China, European Union, India, New Zealand, Philippines, South Africa, Uganda, United States. They appeal in the courts of justice to show that public authorities are failing - both themselves and the generations to come - by neglecting the common natural capital, the climate in particular, or even by acting as accomplices of rogue firms or gangs responsible for far-reaching damages.

Some are rather young, as befits front-line victims of the disasters that loom. In the US, 21 students aged 11 to 22 from 10 different states are suing the federal government over immediate and future damages due to climate change denial or negligence.

Likewise, a group of 25 young people in Colombia filed a suit against the state for failing to stop deforestation in the Amazon basin: the Supreme Court then ruled in their favour. And in 2017, the then nine-year-old Ridhima Pandey challenged the federal government in India’s Supreme Court.

A claim that has been brought against New Zealand’s government illustrates the potential for Māori communities, in their capacity as traditional guardians of the natural environment, to bring claims against governments for failing to properly tackle environmental issues. Their action resonates far beyond New Zealand’s frontiers.


Another student, Greta Thunberg from Sweden, at age 15 started a different type of action, not in courts but in schools. What is the point of children going to school if they have no future? What is the point of them learning sciences if people in positions of responsibility refuse to listen to scientists?

Millions of students have taken part on Fridays. Hence the name of their movement Fridays For Future (FFF) in school strikes for the climate throughout 130 countries. The FFF leaders in several countries – Belgium, Germany, New Zealand, Nigeria, Uganda – often find inspiration and support from a remarkable organization,, founded by William “Bill” McKibben.

Students graduating from ‘elite’ universities used to take plush jobs with bright futures in prosperous firms. For many of them that is no longer the case. They seek compatibility between professional prospects and deeply felt ecological concerns to the point of making firms anxious about their capacity for recruiting the best candidates. For certain employers - particularly those with activities that are fundamentally detrimental to the environment and to the climate in particular - that capacity to compete for talent is seriously dented.


They pioneer ways of producing, storing and consuming energy without killing life on earth and damaging the climate.

They devise and disseminate new materials to save resources. They grow and produce safe food without wiping out biological diversity and polluting to death bodies of water and the soil itself. They profitably manage forests and ocean resources without exhausting them. They renovate cities to make them more resilient, more efficient, less destructive and more hospitable.

Of particular significance is the role that visionary and determined social entrepreneurs, local and regional leaders can play in bringing their communities forward on paths for ecological and economic transition.


Aware of the climate risks, investors rebalance their portfolios away from high carbon footprints (e.g. coal, oil, cement) towards assets positively associated with the transition to a decarbonised economy (e.g. renewable energy providers, producers of efficient materials).

Pioneers such as the Wallace Global Fund and the Rockefeller Brothers Fund have kickstarted this movement for responsible investors. Since 2014 it has gained strong momentum.

Major financial management companies, like BlackRock and Allianz, have made strong climate commitments. So too have major banks, such as HSBC and Standard Chartered. We will, of course, find out about delivery.

Increasingly, investors are recognising that it is the dirty activities of the last century that are risky and in decline, and that it is the clean investments of the twenty-first century that are likely to prosper.

When an investor has rebalanced her portfolio in this way, she is motivated to support those public policies that enhance the value of her new investments – for example, stricter carbon pricing policies. In this sense, private interests and natural capital-friendly public policies might come to converge.

So-called green bonds, and other instruments for financing transition-oriented activities, are emitted and traded under various forms. Their scope is fast growing, particularly in China and in the European Union. Their healthy development is conditional on the formulation and implementation of appropriate public policies and regulations. But their existence and expansion help drive such policies.


Effective communicators are vital in order to amplify and disseminate the messages from policy-makers and from scientists. All the more so as such messages are not easy to convey and as time is short.

President Franklin Delano Roosevelt was able to explain and convince a majority to approve his policies, however unfamiliar these looked initially. Explaining how to shift to a more sustainable development path is no less vital than explaining how to exit from the Great Depression. It requires the same qualities of coherence, clarity and conviction.

In L’Ancien Régime et la Révolution, Livre III (1856), Alexis de Tocqueville shows how in the second half of the eighteenth century mushrooming new visions and actions converged to overthrow a 1,000-year-old French Ancien Régime. This generated a new order, despite seemingly insuperable obstacles. These days we observe a similar pattern with the still fragile perspective of another, potentially broader revolution. Time, however, is severely constrained.

There are many truly outstanding people ‘standing up for a sustainable planet’ that are not included in the actors’ accounts. Indeed many, such as David Attenborough and Jane Goodall, have been ‘standing up’ for longer than any of the editors, authors or actors featured in our book. But at the same time they inspired and encouraged others to do the same, whether through high-profile documentary narration or community initiatives like the Jane Goodall Institute’s TACARE and Roots & Shoots programmes.

We showcase a multitude of individuals who have made exceptional contributions to the protection of our planet. But there are numerous others responsible for pioneering work across the globe that have paved the way for following generations of environmentalists like Davi Kopenawa, Wangari Maathai and Chandi Prasad Bhatt. They are outstanding examples.

Claude Henry is a physicist turned economist who is currently Professor of Sustainable Development at Sciences Po in Paris and Columbia University.

Johan Rockström is joint director of the Potsdam Institute for Climate Impact Research in Germany.

Lord Nicholas Stern is IG Patel Professor of Economics and Government and Chair of the Grantham Research Institute on Climate Change and the Environment at the London School of Economics.

Visit Standing up for a Sustainable World: Voices of Change for their full analysis with the specific, inspiring examples.