I support the research involving the historical reanalysis, NOAA-CIRES 20th Century Reanalysis. This work includes an ongoing effort to improve the early ship observations, and creating improved International Surface Pressure Databank. This past year a new HDF5 dataset V4 was created, with new early ship observations and improved by including each ships bias and uncertainty. Currently I am running an Ensemble Kalman Filter (EnKF) based data assimilation system, NCEP GFS/T254 global atmospheric model to generate an extended higher resolution version of the 20 th Century Reanalysis (20CRv3) spanning 1836 to the present.