She is the co-founder and CEO of Global Thermostat, and co-creator of a carbon removal technology that can reverse climate change. The technology was chosen by MIT Technology Review as one of the Ten Breakthrough Technologies of 2019, a list curated by Bill Gates. She is also a Professor of Economics and Mathematical Statistics at Columbia University, and Director of the Columbia Consortium for Risk Management. She acted as the lead author on the Intergovernmental Panel on Climate Change, which received the 2007 Nobel Prize for its work in deciding world policy with respect to climate change, and she worked extensively on the Kyoto Protocol, creating and designing the carbon market that became international law in 2005. She is the author of more than 300 scientific articles and more than 15 books, including the recently published Reversing Climate Change.