Level 1 IIR products are composed of 3 files which contain radiances seen by each channel of the IIR on a half orbit. Pixels are georeferenced at 1km resolution.
From the geometrical point of view, level 1 products are created using the following method:
- On the ground, a line of 69 pixels of 1 km is built. This 69 km line is perpendicular to the lidar track and centred on it,
- To each pixel thus constituted is allocated a bicubic interpolation of the 4x4 detectors (among the 64x64) of the instrument in flight, which cover this pixel on the ground.
A level 1 IIR product is thus constituted of a series of about 20,000 lines of 69 pixels of 1 km width.
|Corsica and the Gulf of Genoa|
3-channel colour composition: the Cape Corsica is covered by a cold cloud, appearing dark on the image (low luminance in the 3 channels). In the north, the Pô appears with a darker colour than the ground, showing a lower temperature.
Night image, 3-channel colour composition: Budapest is located near the north meander of the river. One can notice the lighter colour of the river compared to the surrounding ground, showing a higher temperature.
|The strait of Gibraltar|
3-channel colour composition: the cold streams along the Spanish and British coasts appear with a dark colour.
|Cape of Good Hope, Cape Town|
3-channel colour composition, channel 8.65 µmm, channel 10.6 µm, channel 12.05 µm: notable differences in luminances between the 3 channels, visible on the ground.