Consistency checks of RSS and super RSS image time sequences and their importance in evaluation of storm top features

Ján Kaňák, SHMÚ

Ján Kaňák conducted consistency checks of RSS and super RSS image time sequences on the base of consultations with Johannes Mueller from EUMETSAT (STG-SWG action-35.13). The resulting full report can be found here.

The main results from this work are:

  1. In spite of the fact that calibration of IR 10.8 micron channel was stable during experiments, Earth’s atmosphere anisotropy influences the measured brightness temperatures of the same scene from different orbit positions (MSG1,2 and 3) in order of 1-2 K during the day. This can slightly influence some quantitative algorithms (NWCSAF, OT detections) applied to data from the same time, for the same region but from different MSG satellites.
  2. During RSS experiments in 2013 by MSG-1 some stronger horizontal (East-West direction) image drifts occurred in south part of imagery, which influenced overall image geometry also over central and northern regions of Europe. Because of short scan time interval (2.5min) also small image drifts can be comparable to the cloud movement and therefor can not be neglected in meteorological interpretation of some small scale features (cloud edges, OT exact positions).
  3. Periodic, but in average small (subpixel) image drifts were found in 2.5min RSS imagery with the period of 30 minutes, which can be neglected in meteorological interpretation.