Climate change real, all is not lost
How we respond to climate change, especially globally but also locally, is the most important debate we can have. While high emotions are understandable — and from a young Swedish girl addressing the world's political and business leaders, highly effective — in the local context we should try to keep it civil.
That the climate change we are experiencing is being driven predominantly by the activities of humans, principally through the burning of fossil fuels and the greenhouse effect, is no longer a matter of debate — although that's not a position that aligns well with scientific rigour, where of course every result and assumption is questioned and tested repeatedly.
The clear trends of a warming planet and changes to our climate, weather patterns and oceans have proven long ago that the vast majority of climate scientists are right; anthropogenic climate change is real, and a global crisis.
We also know from their work that these changes might not happen incrementally; that we risk lurching into an irreversible shift to a hotter world if we pass “tipping points” that, for example, change ocean circulation, cause runaway melting of icesheets and vast methane releases from thawing permafrost — with each heightening the risk of crossing further tipping points.
That there is a limited window of time to drastically reduce our net emissions and start arresting these changes is undeniable.
Our so-called “doom and gloom” merchants on this page are right to be so concerned. They are following the science, however a tendency to focus only on worst-case scenarios does underestimate humanity's ability to come up with technological solutions — as well as the power of market forces when the world imposes carbon taxes at high levels, as it must if we are to tackle climate change effectively.
To counter their gloom with “it's been happening for millennia” isn't a great place to be with regards to the science.
There is no evidence in the ancient climate record for a similar rapid rise in atmospheric CO2 levels such as we have experienced since the Industrial Revolution, when humanity embarked on burning hundreds of millions of years of sequestered carbon in very short order. The last time CO2 in the atmosphere was at current levels for a sustained period was 15m-20m years ago, when the world was 3C to 6C warmer and ice sheets had melted to the point where sea levels rose by 25 to 40 metres.