A Catastrophe Barely Avoided?

"As recently as 18,000 years ago, at the height of the most recent major glaciation, CO2 dipped to its lowest level in recorded history at 180 ppm, low enough to stunt plant growth. [...] Human emissions of CO2 have restored a balance to the global carbon cycle, thereby ensuring the long-term continuation of life on Earth. This extremely positive aspect of human CO2 emissions must be weighed against the unproven hypothesis that human CO2 emissions will cause a catastrophic warming of the climate in coming years."

As someone said: humans may be the biosphere's way of self-preservation by recovering buried carbon.

Full paper – Greenpeace co-founder pens treatise on the positive effects of CO2