Understanding what a problem is, is always the starting point for finding solutions.
So what is the climate emergency all about? Why are changing weather patterns now being referred to as an 'emergency' rather than just climate change?
Those are easy questions to ask, but the answers are long and complicated (and I am not a climate scientist). The mechanism behind rising temperatures - the greenhouse effect - is relatively simple to understand. It is the potential consequences, and the increasing speed of the changes brought about, that are more disturbing to comprehend - and more important.
Please bear with me while I try to outline my understanding...
The Uninhabitable Earth
Anyone my age (in their forties), will have known about climate change for most of their lives; it will have been talked about ever since they were at primary school and Margaret Thatcher was Prime Minister.
They will also remember when the ozone layer and its expanding hole was a huge, existential crisis, and humanity came together to address it by banning the use of CFCs (chlorofluorocarbons, the chemicals once very widely used in aerosols and refrigeration). But there has never been such concerted action on the rise in global temperatures. In fact, despite our collective efforts to recycle and popular support for green energy providers like Ecotricity and Octopus, not a lot has changed in our lifetimes to properly tackle our fossil fuel dependence.
The ozone crisis is interesting in illuminating this lack of real action. There were just ten years between the launch of global ozone monitoring in 1977 and the adoption of the Montreal Protocol, in 1987, committing signatories to the phasing out of CFCs.
The whole story is told here and the contrast with our failure to tackle carbon is stark. The ozone layer won't fully recover until the middle of this century, but as noted by Susan Solomon, a prominent scientist in the work to resolve the ozone problem, had action not been taken, it would have been disastrous:
Had the world not banned CFCs, we would now find ourselves nearing massive ozone depletion. "By 2050, it's pretty well-established we would have had ozone hole-like conditions over the whole planet, and the planet would have become uninhabitable," says Solomon.
Which is where David Wallace-Wells' The Uninhabitable Earth comes in. This book pulls no punches on carbon's own existential threat, from its very first sentence: "It is worse, much worse, than you think."
And it is.
Whilst many activists and concerned citizens have, for decades, made concerted efforts to tackle their individual footprints, not nearly enough is being done at a societal level to make real inroads into the problem.
We are currently adding carbon to the atmosphere at ten times the rate of the planet's last mass extinction event, which started - 250 million years ago - when carbon dioxide warmed the planet by five degrees Celsius, and ended "with all but a sliver of life on Earth dead." (This is only just onto page two.)
By page six, he tells us that we are speeding "blithely" to more than four degrees of warming by the end of this century:
According to some estimates, that would mean that whole regions of Africa and Australia and the United States, parts of South America north of Patagonia, and Asia south of Siberia would be rendered uninhabitable by direct heat, desertification, and flooding. Certainly it would make them inhospitable, and many more besides.
Always that one word chimes again and again: Uninhabitable.
Kyoto
The Kyoto Protocol was signed in 1997 - twenty-five years ago this year - when two degrees of warming was still being talked about as the "threshold of catastrophe," bringing flooded cities, crippling droughts and heat waves, and more intense storms and hurricanes.
There is almost no chance we will avoid that scenario. The Kyoto Protocol achieved, practically, nothing; in the... years since, despite all of our climate advocacy and legislation and progress on green energy, we have produced more emissions than in the twenty years before.
Then came the Paris Agreement in 2016. Another attempt to reset and focus on a problem that wasn't going away. Yet, currently, no single industrial country is on track to meet its Paris commitments. Not one. And so the language has changed.
Scientists, grown tired of the collective shrug that meets their latest climate prognostications, have had to change their vocabulary. As time runs short, we can no longer speak of mere change; the need for action is far more urgent. It is now, truly, an emergency.
Even if, globally, we were to implement Paris overnight, slashing our emissions to meet our commitments, we are still likely to - eventually - get 3.2°C of warming above the pre-industrial baseline.
The tipping point for ice sheet collapse is a mere two degrees, likely by 2100. Say goodbye to Miami, Dhaka, Shanghai, Hong Kong and hundreds of other coastal cities.
Climate models
Most models, by convention, end in 2100. (I will have shuffled off this mortal coil long before then.)
But what often gets lost amid the speed of change, is that climate impact is also long. These changes cannot be undone, like the ozone hole, by reversing course. We can limit what happens in the future, but the generations after us will still have to live with the consequences.
It is also likely that the models are wrong. Not that the climate isn't warming - it obviously is - but that we are underestimating the extent of change by 2100. There is still a huge chance that we could implement Paris and see changes up to four degrees, resulting in a green Sahara and the planet's tropical forests being converted to fire-dominated savanna.
Even if we act now and cut hard and fast, it is almost certain that the 22nd century will be the "century of hell."
And even if we do manage to pull up change short of two degrees, we will still be left with an atmosphere that is 500 parts per million carbon; the last time it was like that was sixteen million years ago and the earth was between five and eight degrees warmer than it is now. That would bring a catastrophic 130 feet of sea-level rise. (I am running out of superlatives.)
Still think the problem is being exaggerated?
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