The year is 1990
1990: The world population is just over 5 billion. Germany is unified. The Soviet Union is imploding. Nelson Mandela is freed from prison. The World Wide Web has been created. West Germany wins the Football World Cup. Wind Beneath My Wings wins Song of the Year at the Grammys.
Annual global greenhouse gas emissions were just over 20 gigatonnes, far fewer than the amount today.
This is all true.
Also in 1990, leading scientists believed that collectively reducing global emissions over the next century would stabilize global temperatures to around 1.5°C of warming.
Each country would simply implement policies to gradually phase out polluting industries and promote alternatives.
Funding would be piled into alternative energy sources.
Emissions would fall by less than one per cent annually.
Why don’t they get on with it and do something?
But that’s not how the story goes.
The political economy of emissions reduction meant emissions continued to rise.
Coal was a cheap, reliable energy source. Cars had internal combustion engines powered by fossil fuels. Established industries provided jobs. People’s knowledge of climate change was minimal and it appeared in the news as an afterthought.
On top of this, the scientific understanding of climate change in 1990 underestimated the threat.
And so between 1990 and 2020, world population increased by about 50 per cent, global GDP more than doubled, millions were lifted out of poverty and natural environments were cleared to accomodate all the new people and their lifestyles.
The year is 2020
Annual global greenhouse gas emissions are closer to 35 gigatonnes
Suddenly, the timeframe to keep warming to less than 1.5°C has become more contracted and emissions must now fall by over 3 per cent per year in order to meet this temperature goal.
And much like a ship heading towards the proverbial iceberg, it has left the world with not only less time to correct course, the correction now requires a sharper turning of the wheel.
In other words, there is less time to do more.
Alongside the increased urgency, the scientific understanding has advanced. We know that reducing emissions to zero must occur much earlier if global temperatures are to stablilize.
As discussed earlier, every tonne of CO2 emitted into atmosphere from today will affect warming into the future.
Also discussed earlier, the warmer the planet gets, the closer we get to breaching potential planetary thresholds.
On a positive note, unlike in 1990, technological research and development has put low emissions technologies within reach. For example, the cost of utility-scale solar PV has decreased by 80 per cent since 2010.
We have very little time if we are to keep warming to less than 1.5°C and the 2020s offer one last chance.
Leaving it too long will require too much change, too quickly at too high of a cost. Global economic and political systems will be unable to adjust to such dramatic changes.
So there’s no option other than to make rapid, deep and sustained cuts in greenhouse gas emissions.