3.6 Million Years

While falling down the Thwaites Glacier hole this morn­ing, there was more cli­mate change news released last week. The num­bers are star­tling, dead­en­ing, and make me stum­ble to find words. We made mil­lion year changes in just one hun­dred. We’ve reshaped the world and don’t even know — or can imag­ine — how yet.

The atmos­pher­ic bur­den of CO₂ is now com­pa­ra­ble to where it was dur­ing the Mid-Pliocene Warm Period around 3.6 mil­lion years ago, when con­cen­tra­tions of car­bon diox­ide ranged from about 380 to 450 parts per mil­lion. During that time sea level was about 78 feet high­er than today, the aver­age tem­per­a­ture was 7 degrees Fahrenheit high­er than in pre-industrial times, and stud­ies indi­cate large forests occu­pied areas of the Arctic that are now tundra. 

National Oceanic and Atmospheric Administration Research