This article first appeared in issue n.16 of Oxygen, sponsored by the Italian energy giant Enel
The powerplants we are building now will define the biosphere of our planet for the next 5000 years.
The math is straightforward, and stark. Carbon dioxide stays in the atmosphere for a long, long time. It takes nearly 5000 years for limestone and rain to scrub the atmosphere of carbon down to plausibly manageable concentrations. It takes half a million years for igneous rock to scrub the atmosphere down to more temperate concentrations.
A coal plant, built today, has an expected lifetime of 50 years or more. Every year, a 1 GW coal plant throws 8 million tons of CO2 into the atmosphere — more than the mass of the Great Pyramid of Giza.
It gets worse. There are roughly the equivalent of a thousand 1 GW coal plants in service today. Collectively, in a decade, they blast 80 billion tons (10 ppm) of CO2 into the atmosphere — approximately the weight of every single living thing on earth. Business as usual for coal plants would make more of a carbon impact that a firestorm burning every living thing on the planet.
We cannot assume that nature will just take care of this mess.
In the past 20 years, electricity generation worldwide doubled. In the next 20 years, it will double again. If we build those plants the way we have been building them, and run them for the 50 years we expect them to last, we will nearly double the amount of carbon dioxide in the atmosphere from when, at 275 ppm, civilization emerged, to 500 ppm, and beyond.
Some policy makers say that reaching 450 ppm would be stable for the Earth. Some scientists (350.org) fear that 350 ppm — much less than the current 396 ppm, is necessary. But as our climate models are making clearer and clearer, blasting to 500 ppm and beyond is not safe territory.
Where that leaves us?
We need more than a faith-based strategy. We need to ask ourselves, what does this mean for us?
For the past many hundreds of millions of years, there have been three major earth climates.
There’s hot earth — greenhouse earth. Ice thaws, and organic matter rots, releasing methane, a potent greenhouse gas, and CO2. Oceans stratify, building hot, nutrient poor layers of water atop the oceans, preventing oxygen from reaching the layers below. Ocean life dies off rapidly, and the focus of life escapes to land. Temperate regions become vast, arid landscapes, and fires and megastorms spread throughout the landmass.
There’s cold earth — icehouse earth. Glaciers blanket and mould the landscape, reflect the sun, and cool the land. Life, crowded out of the land, find its greatest vitality on the sea shelf. Oceans recede — land bridges emerge. Megafauna dot the continents. In the colder periods, the imposing glaciers grow and dominate; in the warmer periods, environmental niches for life open up, for upward new species, like mankind.
We humans emerged in a warmer period of an icehouse earth. We spilled out and filled the alluvial plains of every corner of this planet, built towns, and roads, and cities, covering 3% of the planet surface, and engineered the biosphere, consuming a quarter of its output, disrupting three quarter of the fertile land, and 90% of the biosphere, growing and replicating until we, and our livestock, and our pets, collectively outweigh wild nature, land and air animals, by 50 to 1.
Which brings us to now.
This third era, the anthropocene — the manmade epoch, is without precedent. We would have had another ice age, had humans not intervened. The atmospheric record and the climate tracks the technological and social development of civilization for more than a thousand years. We consume more energy than the tides and waves could ever supply — co-opt more water than our aquifers can sustain, consume more of the food chain directly than any other thing species. We are a force of nature; rivaled, perhaps, only by the powers of the sun, wind, earth, ocean and time.
Scientists fear that our climate is moving away from its zone of temperate stability; the nice, comfortable climate to which we have been adapted. Fish swim in the ocean. Tropical diseases are contained. Tropical agriculture is possible — megadroughts and ultrafloods and superfires are avoided.
Business as usual is now heading towards greenhouse earth. Unless we do something, and do something quickly, unless we face these problems, invent solutions, and scale them up faster, in an absolute sense, than any industry has ever scaled up before, then we will live in that greenhouse earth. What will it really feel like? Maybe we’ll adapt. Life will survive; much of the planet’s history is of a greenhouse earth. But one thing is for certain. We won’t find comfort easily. Greenhouse earth is for crocodiles.
Human beings must realize that we are now in the driver’s seat. We need to know where were going, and we need to talk about where we want to go, and we ask ourselves if we have the courage to turn the wheel.