Erik Larson is an atmospheric scientist interested in Earth and planetary atmospheres, which he studies with numerical models. He is visiting MIT from the University of Colorado and NOAA, where he is a research scientist with the Chemical Sciences Division. His research includes estimating Earth's radiative forcing and energy budget from the CMIP5 output. HE and Dr. Portmann (NOAA) developed a new method to calculate radiative forcing in transient climate simulations. He also develops and applies the NCAR CESM model to problems including the effects of rocket emissions and the seasonal cycle of aerosols on Titan.