Between 2025 and 2070, scientists estimate about half the planet may be developed.
About 50 years from now, half of the planet may be developed by agriculture and urbanization. This will upset the balance needed to sustain life. The planet could go into a tipping point where climate and biological decline changes life as we know it. Scientists say the idea that great climate change may take place is frightening, but real.
The last ice age peaked just 20,000 years ago, a short period in geological time. It was a climate very different from the one human beings are used to for the last few thousand years. The last ice age ended around 11,000 years ago.
It is important to understand just how much human beings have changed the planet. Human population is four times greater than it was a century ago. The earth is now 43 percent agriculture or urban. The concentration of carbon dioxide in the atmosphere has increased by more than a third. We have made the oceans more acidic. All of these changes are speeding up, not slowing down.
The authors of the study say current trends point to half the Earth’s land surface being disturbed by human activity between 2025 and 2070. They say that could represent the point of no return for a livable planet.
One scientist said ” Looking into the past tells us that it can really happen, I think if we want to avoid unpleasant surprises, we want to stay away from that 50% mark.”
In the desperately poor and hungry parts of sub-Saharan Africa and in the hot and dry patches of the American southwest, a tipping point may have already been reached and passed.
The scary thing about a tipping point is that you only know for sure that it exists once you’ve reached it — and after that, it is too late to go back.