Satellite du jour – Océan Indien (clor nat)
The Natural Colour Enhanced product is an RGB which utilises three SEVIRI solar channels: NIR1.6, VIS0.8 and VIS0.6. It is similar to a Natural Colour RGB product, with the difference that the ice-clouds and snow covered surfaces and clouds are not shown in typical cyan colour but in desaturated tones, i.e. in white shades, making it more natural for human perception. From 1 June 2022, Meteosat-9 at 45.5° E is the prime satellite for the IODC service, replacing Meteosat-8 (located at 41.5° E while in operation).
Satellite du jour – Océan Indien (day Mcr)
The Day Microphysics RGB (Red, Green, Blue) was inherited from Rosenfeld and Lensky (1998): the VIS0.8 reflectance in red approximates the cloud optical depth and amount of cloud water and ice; the IR3.9 solar reflectance in green is a qualitative measure for cloud particle size and phase, and the IR10.8 brightness temperature modulates the blue. This color scheme is useful for cloud analysis, convection, fog, snow, and fires. In this colour scheme water clouds that do not precipitate appear white because cloud drops are small, whereas large drops that are typical to precipitating clouds appear pink, because of the low reflectance at IR3.9 manifested as low green. Supercooled water clouds appear more yellow, because the lower temperature that modulate the blue component. Cold and thick clouds with tops composed of large ice particles, e.g., Cb tops, appear red. Optically thick clouds with small ice particles near their tops appear orange. From 1 June 2022, Meteosat-9 at 45.5° E is the prime satellite for the IODC service, replacing Meteosat-8 (located at 41.5° E while in operation).