Must-read Hansen and Sato paper: We are at a climate tipping point that, once crossed, enables multi-meter sea level rise this century – ThinkProgress

Must-read Hansen and Sato paper: We are at a climate tipping point that, once crossed, enables multi-meter sea level rise this century – ThinkProgress

Right now, we’re headed towards an ice-free planet. That takes us through the Eemian interglacial period of about 130,000 years ago when sea levels were 15 to 20 feet higher, when temperatures had been thought to be about 1°C warmer than today. Then we go back to the “early Pliocene, when sea level was about 25 m [82 feet] higher than today,” as NASA’s James Hansen and Makiko Sato explain in a new draft paper, “Paleoclimate Implications for Human-Made Climate Change.”

The question is how much warmer was it in the Eemian and early Pliocene than today — and how fast can the great ice sheets disintegrate?

We already know we’re at CO2 levels that risk catastrophe if they are sustained or exceeded for any extended period of time (see Science: CO2 levels haven’t been this high for 15 million years, when it was 5° to 10°F warmer and seas were 75 to 120 feet higher).

via Must-read Hansen and Sato paper: We are at a climate tipping point that, once crossed, enables multi-meter sea level rise this century – ThinkProgress