Human evolution can seem like a phenomenon of the distant past which applies only to our ancestors living millions of years ago. But human evolution is ongoing. To evolve simply means that mutations – the accidental changes to genes that happen normally in the process of copying DNA – are becoming more or less common in the population over time.
A concerted effort to end slavery around the world is a big investment, but one that can have a huge global impact. Enforcement of the anti-slavery laws that are on the books in every country would immediately diminish CO2 emissions and species loss. In developing countries ending slavery can stimulate the economy, ward off the threat of rising sea levels or destructive deforestation, and preserve endangered species. Freed slaves can also be paid to replant the forests they were forced to cut. This would not only help to rehabilitate the land, but it would also help to give work and a wage to some of the people who need this most in the world.
The Antarctic Ice Sheet stores water equivalent to 58 m in global sea-level rise. We show in simulations using the Parallel Ice Sheet Model that burning the currently attainable fossil fuel resources is sufficient to eliminate the ice sheet. With cumulative fossil fuel emissions of 10,000 gigatonnes of carbon (GtC), Antarctica is projected to become almost ice-free with an average contribution to sea-level rise exceeding 3 m per century during the first millennium. Consistent with recent observations and simulations, the West Antarctic Ice Sheet becomes unstable with 600 to 800 GtC of additional carbon emissions. Beyond this additional carbon release, the destabilization of ice basins in both West and East Antarctica results in a threshold increase in global sea level. Unabated carbon emissions thus threaten the Antarctic Ice Sheet in its entirety with associated sea-level rise that far exceeds that of all other possible sources.