TY - CPAPER AU - Erik Andersson AU - Mike Fisher BT - Workshop on Diagnosis of Data Assimilation Systems, 2 - 4 November 1998 CY - Shinfield Park, Reading DA - 1999 LA - eng PB - ECMWF PP - Shinfield Park, Reading PY - 1999 SP - 81 EP - 90 T2 - Workshop on Diagnosis of Data Assimilation Systems, 2 - 4 November 1998 TI - Background errors for observed quantities and their propagation in time ER -