MSG IR10.8 and WV7.3 imagery: time sequence
9th June 2004: 0000UTC
At 00 UTC we find a few small areas in the WV-image with temperatures below -65°C and bigger areas in the corresponding IR-image (indicated by blue). If the IR-image reveals lower temperatures than WV overshooting is likely. If the WV-image exhibits temperatures below the tropopause the overshooting recently happened because the time period between the detrainment and the image’s processing was too short for the adaption of the water vapour to the warmer stratosphere (about -60°C). If we find blue pixels in the IR but none in the the WV the cloud tower due to overshooting still exists. However, because the detrainment of water vapour occured some time ago the it adapted already to the relatively warm stratosphere.
