Cirrus morning.  Cirrus clouds and waves in these, various halo phenomena, contrails (condensation trails) and their shadows. Visibility of several types of halo phenomena changes here significantly with varying microphysical composition of cirrus clouds passing above. As regards contrails and their shadows, only those contrails which are higher than the regular cirrus clouds cast shadows on these. Moreover, location of the contrail shadows with respect to the contrails themselves depends on their relative position to the Sun.  The timelapse was captured from Praha - Kačerov, Czech Republic.

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I was also curious to see how well these contrails can be seen in satellite imagery, namely in the M09 band (1.38 µm) of the VIIRS instrument bands, flown on NPP and NOAA-20 satellites. The 1.38 µm band will be one of the new bands of Flexible combined Imager (FCI) on Meteosat Third Generation (MTG) satellites, first of which (MTG-I1) is to be launched by the end of this year (Dec 2022). To learn what we can expect from FCI data, other recent satellites and their instruments, which already have some of the upcoming MTG FCI new bands, are used - including VIIRS. Also, the RGB Cloud Type image product (below) utilizes the 1.38 µm band. Some examples of utilization of the 1.38 µm band can be found here or here.

• NPP VIIRS  images and products, 11:50 UTC (time of the end of the timelapse):  I-bands (375m)  RGB125,  I5 band,  BTD I5-I4, M-bands (750m)  M09 (1.38 µm),  RGB Cloud Type, RGB 24M. Contrails can be seen very well here, in most of these images, probably best in the RGB 24M. Though, in this case (detection of contrails above or within natural cirrus layers) the 1.38 µm band does not provide any new information, and the same is true for the RGB Cloud Type image product.

For comparison, below are three loops from present MSG-3 (Meteosat Second Generation) satellite, its SEVIRI instrument. Typically, the contrails can be seen well e.g. in the RGB 24M image product, but not in this case:

• MSG SEVIRI  loops:  RGB VIS-IR,  RGB 24M and WV6.2 show extent and motion of the cirrus clouds, but none of these is capable of distinguishing the contrails in this case.

More information about various RGBs and other image products from present and future satellites can be found e.g. here:
www.eumetrain.org/rgb_quick_guides/