Karoly has served as a lead author for the Intergovernmental Panel on Climate Change (IPCC) Working Group 2 (on societal impacts) and he is a member of the faculty of the School of Earth Sciences at the University of Melbourne. His work, along with that of the many other lead authors and review editors, contributed to the award of the 2007 Nobel Peace Prize, which was won jointly by the IPCC and Al Gore. He is member of the board of the Climate Change Authority.