INTRODUCTION:
WHAT IS CLIMATE CHANGE?

Anyone picking up this book might wonder about its title. We Are the Weather Makers is a serious thing to say. And if anyone had said to me a decade ago that our planet was in urgent danger I wouldn’t have paid much attention. The story of this book is what I’ve learned since then, and how I came to change my view.

In the last decade climate science has undergone a revolution, and now we understand a great deal more about Earth’s climate system and how it is changing. Climate is always changing, of course, but it is now doing so at an unnatural pace, and we are causing it. Unfortunately, most of those changes will damage our world.

I’ve written this book in the hope that people can continue to have the chance, as I did, to stand on a glacier high atop a tropical mountain, and to look way down over dense jungles, plains and mangrove swamps, and finally see tropical reefs in the distance.

It should be everyone’s birthright to experience our wonderful planet to the fullest, to have the chance to see polar bears, great whales and Antarctic glaciers in real life. I believe that it’s profoundly wrong to deprive future generations of this just so we can continue wasting electricity and driving oversize cars.

And I want to empower readers: our leaders in politics and business need to hear your voice. I hope this book helps you to act firmly, because if you let them continue doing things in the same old ways you will become part of their failure.

In 1981, when I was in my mid-twenties, I climbed Mt Albert Edward, one of the highest peaks on the tropical island of New Guinea.

Tree-fern grassland in the Star Mountains, central New Guinea. It was this habitat I noticed disappearing under encroaching forests, as a result of global warming.

The bronzed grasslands of the summit were a contrast to the green jungle all around, and among the alpine tussocks grew groves of tree-ferns, whose lacy fronds waved above my head.

Downslope, the tussock grassland ended abruptly at a stunted, mossy forest. A single step could carry you from sunshine into the gloom, where the pencil-thin saplings were covered with moss, lichens and filmy ferns.

In the leaf litter on the forest floor I was surprised to find the trunks of dead tree-ferns. Tree-ferns grew only in the grassland, so it was clear that the forest was climbing towards the mountain peak. I guessed it had swallowed at least thirty metres of grassland in less time than it takes for a tree-fern to rot on the damp forest floor—a decade or two at most.

Why was the forest expanding? I remembered reading that New Guinea’s glaciers were melting. Had the temperature on Mt Albert Edward warmed enough to permit trees to grow where previously only grasses could take root? Was this evidence of climate change?

I am a palaeontologist, someone who studies fossils and geological periods, so I know how important changes in climate have been in determining the fate of species. But this was the first evidence I’d seen that it might affect Earth during my lifetime. I knew there was something wrong, but not quite what it was.

Despite the good position I was in to understand the significance of these observations, I soon forgot about them. What seemed like more urgent issues demanded my attention. Rainforests were being felled for timber and to make agricultural land, and the larger animal species living there were being hunted to extinction. In my own country of Australia, rising salt was threatening to destroy the most fertile soils. Overgrazing, water pollution and the logging of forests all threatened precious ecosystems and biodiversity—the range and variety of life forms that exist in our environment.

So is climate change a huge threat, or nothing to worry about? Or is it something in between—an issue that we must soon face, but not yet?

Even scientists don’t agree on every aspect of climate change research. We are trained sceptics, always questioning our own and others’ work. A scientific theory is only valid for as long as it has not been disproved. And climate change can be difficult for many people to think about calmly because it arises from so many things we take for granted in the way we live.

Some things about climate change are certain. It results from a special kind of air pollution. We know exactly the size of our atmosphere and the volume of pollutants pouring into it. The story I want to tell here is about the impacts of some of those pollutants (known as greenhouse gases) on all life on Earth.

For the last 10,000 years Earth’s thermostat, or climate control, has been set to an average surface temperature of around 14°C. On the whole this has suited human beings splendidly, and we have been able to organise ourselves in a most impressive manner—planting crops, domesticating animals and building cities.

Finally, over the past century, we have created a truly global civilisation. Given that in all of Earth’s history the only other creatures able to organise themselves on a similar scale are ants, bees and termites—which are tiny in comparison to us and have small resource requirements—this is quite an achievement.

Earth’s thermostat is a complex and delicate mechanism, at the heart of which lies carbon dioxide (CO₂), a colourless and odourless gas formed from one carbon and two oxygen atoms.

CO₂ plays a critical role in maintaining the balance necessary to all life. It is also a waste product of the fossil fuels—coal, oil and gas—that almost every person on the planet uses for heat, transport or other energy needs. On dead planets such as Venus and Mars, CO₂ makes up most of the atmosphere, and it would do so here if living things and Earth’s processes didn’t keep it within bounds. Our planet’s rocks, soils and waters are packed with carbon atoms itching to combine with oxygen and get airborne. Carbon is everywhere.

For the past 10,000 years CO₂ has made up around three parts per 10,000 in Earth’s atmosphere. That’s a small amount—0.03 per cent—yet it has a big influence on temperature. We create CO₂ every time we burn fossil fuels to drive a car, cook a meal or turn on a light, and the gas we create lasts around a century in the atmosphere. So the proportion of CO₂ in the air we breathe is now rapidly increasing, and this is causing our planet to warm.

The matanim cuscus. This woman’s husband caught the rare creature in the forests of central New Guinea in 1985. It may well already be extinct as a result of climate change.

By late 2004, I was really worried. The world’s leading science journals were full of reports that glaciers were melting ten times faster than previously thought, that atmospheric greenhouse gases had reached levels not seen for millions of years, and that species were vanishing as a result of climate change. There were also reports of extreme weather events, long-term droughts and rising sea levels.

We cannot wait for someone to solve this problem of carbon emissions for us. We can all make a difference and help combat climate change at almost no cost to our lifestyle. And in this, climate change is very different from other environmental issues such as biodiversity loss or the ozone hole.

The best scientific evidence indicates that we need to reduce our CO₂ emissions by 70 per cent by 2050.

How can we do this?

If your family owns a four-wheel-drive and replaces it with a hybrid fuel car, which combines an electric motor with a petrol-driven engine, you can instantly cut your transport emissions by 70 per cent.

If your home’s electricity provider offers a green option, you will be able to make equally major cuts in your household emissions for the daily cost of an ice cream. Just ask for your power to come from renewable energy sources such as wind, solar or hydro.

And if you encourage your family and friends to vote for a politician who has a deep commitment to reducing CO₂ emissions, you might change the world.

We have all the technology we need to change to a carbon-free economy. All we need is to apply our knowledge and develop our understanding. The main thing stopping us going forward are the pessimism and confusion created by people who want to go on polluting so that they can make money.

Our future depends on readers like you. Whenever my family gathers for a special event, the true scale of climate change is never far from my mind. My mother, who was born when motor vehicles and electric lights were still novelties, glows in the company of her grandchildren, some of whom are not yet ten.

To see them together is to see a chain of the deepest love that spans 150 years, for those grandchildren will not reach my mother’s present age until late this century. To me, to her, and to their parents, their welfare is every bit as important as our own.

Climate change affects almost every family on this planet. Seventy per cent of all people alive today will still be alive in 2050.