The main focus of the ICE sheet StatE Estimation (ICESEE) Project is the development of an open-source software package for applying transient ensemble Kalman filtering techniques to a wide range of ice sheet models, enabling the seamless integration of glaciological and geological observations with physical models. Two initial case studies will focus on reconstructing past glacier changes and using these reconstructions to initialize future predictions of change at Sermeq Kujalleq (aka Jakobshavn Isbrae) in Greenland and Thwaites Glacier in West Antarctica. The final part of this project will add these data assimilation capabilities to a cloud-based ice sheet model with a browser-based interface so that it can be used to directly assimilate data from a community repository of ice sheet observations during simulations of past and future glacier behavior.