Climate change is getting worse than earlier thought.
https://edition.cnn.com/2019/01/25/opinions/climate-change-getting-worse-intl/index.html***********
To get a full grasp of climate change, you need to take a geological perspective. Wind the clock back all the way through human history, past the Romans and through the Stone Age, to the time before modern humans evolved, and our ape ancestors roamed in Africa.
Roughly three million years ago, in an epoch called the Pliocene, was the last time carbon dioxide levels were as high in the atmosphere as they are now. In other words, today's CO2 concentrations -- at about 410 parts per million -- are higher than at any time during the existence of Homo sapiens.
But it's the rate of change that is really off the charts, even geologically. Humans are now transferring 10 billion tonnes of carbon from the earth's crust -- in the form of combusted coal, oil and gas -- into the atmosphere each year.
When I wrote Six Degrees back in 2007 I felt that there was at least an odds-on chance of stabilizing global temperatures at or below 2 degrees Celsius, the policy target that was later agreed by world leaders at the Paris climate conference in 2015.
This now looks deluded. Achieving the two-degrees target would require the whole world to cut its net carbon emissions to zero by mid-century, and to go carbon-negative -- somehow hoovering up hundreds of billions of tonnes of extra carbon dioxide using technology yet to be invented -- from the atmosphere for decades thereafter.
In the real world, the opposite is happening. Emissions reached a new record last year, dragging us ever closer to the worst-case scenarios employed by climate models, which yield four degrees or more by the end of this century.
There is no known geological precedent, for at least the last half-billion years of the history of life on earth, for climate change of the magnitude now projected this century to take place over such a short period of time.
To think that young people alive today will experience all of this within their lifetimes is an extraordinary thought indeed.
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