Some nations, mostly wealthy ones, have made voluntary commitments to reduce their emissions. The United States, for example, has agreed to take its emissions 17 percent below 2005 levels by 2020.
Unfortunately, added together, all of the nations' proposed cuts — if successful — would lead to about 5.8 degrees F (3.2 degrees C) warming by the year 2100, a significant distance from the target of 3.6 degree F, according to calculations by the independent science-based project Climate Action Tracker.
These voluntary commitments to reduce emissions are a "very, very positive sign," said Niklas Höhne, director of energy and climate policy for the independent research and consulting company Ecofys, one of the organizations behind Climate Action Tracker. "That is the real problem, so the ambition level is not sufficient on these voluntary actions."