Think we don’t have a choice when it comes to saving the planet? Think again

Climate change is increasingly causing global disruption. Human beings naturally seek certainty and modern societies have long taken for granted the relative certainties of the weather. That assumption underpins everything, from insurance, to food security, to global trade, to mass tourism.

We travel and we trade as if that certainty is a given, and we insure against the once-in-a-hundred-years occasion that it isn’t. Indeed, our whole free enterprise system depends on businesses being able to restrict their risks and limit the call on their capital. Insurance and the limited liability company are the necessary facilitators of capitalism.

However, as each year is hotter than the last; as wildfires rip through whole nations and are followed by floods and hurricanes of unparalleled force and extent; and as no part of the world is spared extreme weather events, the insurance model is fundamentally threatened and the ability to limit risk undermined.

From individual homeowners, no longer able to insure against flooding, to great international businesses that can’t protect their global supply chains, a warming world is disrupting the very system that has brought us unparalleled prosperity and opportunity. And every year it gets worse and more extensive.

2023 was the hottest year on record. Canada experienced its worst fire season and there were catastrophic blazes in Hawaii, the Mediterranean, central Amazonia, and Chile. The ferocity and the spread grows apace – and with it, the indirect effects.

People who have no water for their children invade their neighbours who have. Unparalleled levels of heat drive men and women to move – not for a better life, but just to be able to live. The migration that is already a toxic issue throughout Europe and North America is eclipsed when heat becomes intolerable, state structures collapse, and whole nations like Bangladesh are awash with rising sea levels.

The numbers on the move will be of a different order in a world where the rich nations have already shown themselves unable to deal with immigration. They’ve seen nothing yet!

However, this is not just a human disaster. We are sustained by what may well be a unique environment. Centuries of astronomy have not revealed another world capable of maintaining life as we know it. It seems that planet Earth is a rare phenomenon which may well depend on some delicate balances.

It was once too hot to support life, and it was the emergence of trees and bushes that gradually took carbon out of the atmosphere and enabled the emergence of fish and reptiles, insects and mammals, and finally human beings. Those decaying trees laid that carbon down to become, over millennia, coal, oil, and gas. For 200 years we have been putting that carbon back into the atmosphere, so it isn’t surprising that we’ve reversed the cooling and turned up the heat.

And, if the process continues, we don’t know what that will produce. Already, global warming has shifted the earth’s energy balance with unprecedented flows of heat into the oceans; ice caps; soils; and atmosphere. The rate has doubled in less than 50 years, and, as the melting ice caps move more water towards the centre of the globe, it slows the planet’s rotation and lengthens our days.

Almost imperceptible at the moment but, if we allow the effect to increase, it could begin to counter the moon’s attraction on which we depend for the relative stability of our climate. The sheer scale of what is happening means that the ocean currents, like the Gulf Stream, could change entirely and with them the weather patterns that they control.

This is why scientists have sought to convince the world to keep warming below a 1.5-degree increase. Anything more and we really cannot tell what cataclysmic changes would occur. Although we can go back more than a million years and trace temperatures and the air’s carbon content by analysing the layers of ice, we can find no comparable warming.

The ebb and flow of warm and cold periods continues as it has always done, but nothing like the global heating that has grown persistently since the beginning of the industrial revolution. That is entirely unprecedented, man-made, and already very close to levels that are likely to be catastrophic.

So, as American cities black out because of wildfires; China wrestles with persistent drought; Greece battles to protect its monuments from the flames; Niger swelters with temperatures of more than 40 degrees; and even the East of England is officially designated a semi-arid region – the world has a choice.

If this is what we get with 1.5 degrees warming, do we still cling to business as usual until 3 degrees warming produces results we hardly dare contemplate? Or does humankind rise to the occasion and meet the global threat with a global response, creating a new industrial revolution in which renewable energy powers a society that doesn’t cost the Earth, but builds a cleaner, greener, and fairer world?

It is the fundamental challenge of the human condition. We can rise to the heights or disappear in the depths. We have the choice.

John Gummer, Lord Deben, served as Conservative Party chairman under Margaret Thatcher and as environment secretary in John Major’s government