Progress and Prospects for Reanalysis for Weather and Climate

Analyses of global atmospheric observations in real time for numerical weather prediction (NWP) lack continuity over time as the operational system evolves. Reanalysis of the observations—with more complete data, improved quality control, and a constant state‐of‐the‐art assimilating model and analysis system—greatly improves the homogeneity of the record and makes it useful for examining climate variations. This whole endeavor is now referred to as “reanalysis.”