Writing a book about climate change ought to be one of the least controversial things a member of the Royal Family can get up to these days. An overwhelming majority of scientists agree that manmade carbon emissions are causing global temperatures to rise. From the Chinese president to the World Bank and the Pope, the world’s leading political, financial and religious institutions agree too. So it’s quite surprising that the publication of Prince Charles’s Ladybird book on climate change should have caused such a stir. And equally surprising that sources within the White House are worrying about the possibility of our future king raising the matter with Donald Trump during his state visit to the UK.
But the stakes couldn’t be higher.
Take the temperature rise of 1 degrees C, announced by NASA at the beginning of the year. It may sound insignificant, nothing much to worry about. That’s what former UK Environment Secretary, Owen Paterson, recently said on a BBC Question Time panel. He wasn’t challenged particularly strongly. It can be hard for us humans to grasp the huge import of such a seemingly small rise, especially given the massive fluctuations in temperature between winter and summer or night and day.
Paterson and his friends in their post-referendum euphoria started talking about ‘Clexit’, where Britain’s Climate Change Act and our commitment to the Paris climate agreement would join our membership of the EU on the scrapheap of history. There was just one exit they forgot to include – leaving the current epoch we call the Holocene.
The recent history of Earth shows that our home planet has oscillated pretty regularly between ice ages (when mile-thick glaciers spread as far as London) and interglacials – periods of time when the ice receded to the poles. In general those ice ages lasted a hundred thousand years or so, followed by a twenty to thirty thousand year-long interglacial. It was a natural cycle tied mainly to changes in the Earth’s orbit of the Sun.
Right now we are in an interglacial. It started about eleven thousand years ago and it’s called the Holocene. It is a climatic sweet spot that allowed us to develop the extraordinarily complex societies we live in today. For those eleven thousand years the temperature of Earth has been just perfect. For humans it has been a Garden of Eden.
Not all interglacials are so suited to human development. Earlier interglacials have been slightly warmer than the Holocene, and by peering back into the geological record we can gain an understanding of what life on a warmer planet might be like. An Earth 3 degrees warmer than our own saw sea levels 25 metres higher than today’s – an Earth where London is a fjord and the Netherlands is an island the size of Dartmoor.
Seemingly small differences in global average temperature on planet Earth really do matter. They matter more than any other number we hear on the news.
For the duration of the Holocene the average global temperature has not shifted by more than one degree Celsius either way. Until, that is, we started burning billions of tonnes of carbon every year. It takes an unimaginably vast amount of energy to warm the atmosphere, the land and particularly the oceans by one degree. But that’s what we’ve done.
The Holocene is almost perfect for us, and our societies evolved to suit the Holocene. But now scientists say the Earth is undergoing changes that are bringing the perfect epoch to an end.
If the present accumulation of carbon dioxide in the atmosphere continues unchecked, greenhouse warming of more than 3 degrees C might occur by the end of this century – a scale and speed of change that is unprecedented. Fuelled by two centuries of industrial growth, today’s atmospheric carbon dioxide levels exceed those reached at any point during the last several million years.
As a result, say scientists, we are entering a new geological epoch. Soon, they claim, we will no longer live in the Holocene. Instead we will live in the Anthropocene – the age of humans, when one species has the same power to radically change our planet as a meteor strike or a shift in the Earth’s axis. We are waving goodbye to our Garden of Eden.
Until very recently we still had space in the atmosphere to dump our CO2 emissions, space in the oceans to dump our waste and ample biomes like rainforests to exploit. But now we’ve hit our credit limit, the biophysical ceiling of the planet’s capacity to support our species.
In the grand sweep of geological time this has all happened very quickly. It started in the 1750s in the United Kingdom with the start of the industrial revolution. It continued through what has been termed the ‘great acceleration’ in the 1950s, when production and consumption really took off, ultimately leading to the sixth mass extinction of species (the first to be caused by one species – us). As a result of climate change, abrupt changes started to occur to the Earth – the rapid melt of Arctic sea ice, the retreat of glaciers worldwide and massive bleaching of coral reefs. And all this has happened with just a 1 degree C rise in global average temperatures.
So 1 degrees C is important. It’s about as important as it gets. Not as a tool to scare, but as a motivation to act. Humans can live outside the Holocene. We’ve done it before. A few million hunter-gatherers in the last Ice Age. But if we see ourselves as we are, a complex civilisation of seven billion people, maybe rising to nine billion, the scientific message becomes as simple as it is dramatic – that the Holocene is the only state of the planet that we know for certain can support us.
In December 2015, 195 governments agreed in Paris to a long-term goal of keeping the increase in global average temperature to well below 2 degrees C above pre-industrial levels, with the aim to limit the increase to 1.5°C. This was important because it meant that the governments of the world recognised how dangerous that seemingly small increase in temperature really is, and that the temperature goal can only be achieved through collective effort.
To meet that Paris temperature goal, we’re going to have to rethink the concept of the global commons – those shared spaces that belong to no one and everyone. The atmosphere, the high seas, the Arctic ice sheets which reflect incoming heat back out to space, functioning as the world’s air conditioner, helping to cool the planet. All are fundamental to keeping the earth system in a habitable interglacial state.
It means we have to leave most of our reserves of coal, oil and gas in the ground and end deforestation. We need to end the internal combustion engine and shift to electric vehicles. We need to rapidly develop renewable energy and storage technology. We need to eat a more plant-based diet in order to end agricultural expansion into forests and other vulnerable ecosystems. We need those biomes to recover in order to store more carbon and protect biodiversity. And we need to move from a linear to a circular economy – reducing, reusing and recycling.
The technologies are ready but the politics lags far behind. The men and women in charge today are part of the first generation that truly know the threat we face from climate change, and the last generation who can do something about it. One degree sounds like one small step, but it is a step out of Eden and the only home we have ever known.
John Sauven is executive director of Greenpeace.