Meehl uses computer models and atmospheric observations to examine both present and future climate change. He is an expert on the likely impacts of global warming on extreme weather events, such as droughts, floods, and heat waves. He also studies "climate commitment" – the extent to which warming would continue even is society were to immediately cut all greenhouse gas emissions. Meehl has also analyzed the impact of the solar cycle on climate patterns on Earth. He has served as convening lead author and lead author for scientific assessments by the Intergovernmental Panel on Climate Change (IPCC) and shared in the 2007 Nobel Peace Prize. Meehl is a senior scientist in NCAR's Climate and Global Dynamics Division.