The purposes of monitoring the data assimilation system are to ensure the proper performance of the assimilation system and to diagnose problems with the system for future improvements.

The vertical plots plots include observation number, observation number rejected by gross check and by variational quality control, observation number monitored averaged over 10 regions: global(90S-90N, 0-360E),Northern Hemisphere (20N-80N, 0-360E),Southern Hemisphere (20S-80S, 0-360E), Tropics (20S-20N, 0-360E),USA (25N-50N, 125W-65W), Canada (50N-90N, 125W-65W),North and Central America (0N-90N, 165W-60W), South and Central America (0S-90S, 165W-60W),Europe (35N-70N, 10W-25E), Asia (5N-45N, 65E-145E).

The plots also include the bias, rms, contribution to penalty and contribution to penalty with variational qc averaged over those 10 regions.