The fact is that CO2 levels are at a historic low in the planetary history. Historical levels have NORMALLY been around 1000-3000 parts per million (as compared to the current 380 ppm). Which means that NATURE has played a huge roll in sequestering a huge quantity of the gas, because MAN DID NOT YET EXIST!!
No one denies this. That is where we are getting all these fossil fuels to burn, and put back into the atmosphere. There was also the development of C4 plants, which use far more carbon than previous plants. And more abundant sea life that over millions of years sequestered carbon in seabeds.
When put into the perspective of the paleo-climatic record, we're at a historical low level of CO2, which indicates that you're trying to push against the planetary pendulum and doomed to failure).
But sea levels have historically been higher than they are now too. We have built our civilization based on sea levels at this level. If we go back to 1000 ppm or more of GHGs in the atmosphere, and melt the ice that has been built up over the past 30-35m years, then sea levels will increase, and wipe out large amounts of land that has been developed. And harm the species that are adapted to this particular climate. Sure the planet at large will adapt. Everyone and every species won't be wiped out. But there will be enormous dislocations and extinctions. Especially if abrupt climate change occurs. What research over the past 20 years or so has shown is that climate can change really really quickly, far more quickly than previously believed, under certain conditions. Those conditions will vary. But it can and has at times changed pretty dramatically over a period of decades, not centuries or millennia, as previously believed. |
