November 19, 2023

Example level 1 qualified Products from the Infrared Imager

Level 1 IIR products are composed of three files which contain radiances seen by each channel of the IIR on a half-orbit. Pixels are 1 km x 1 km and georeferenced.

From a geometric standpoint, level 1 products are generated using the following method:

  • On the ground, a line of 69 pixels of 1 kilometre is generated. This 69-km line is perpendicular to the lidar track and centred on it
  • A bi-cubic interpolation of the 4x4 detectors (among the 64x64) of the instrument in flight is then allocated to each pixel thus generated. These detectors cover this pixel on the ground.

A level 1 IIR product thus consists of a series of about 20,000 lines of 69 pixels 1 km on a side.

Corsica and the Gulf of Genoa
Three-channel colour composite: the Cap Corse is covered by a cold cloud, which appears dark on the image (low brightness in the three channels). In the north, the Pô appears darker than the ground, showing a lower temperature.

Corsica and the Gulf of Genoa
Night image, three-channel colour composite: Budapest is near the north meander of the river. Notice the lighter colour of the river compared to the surrounding land, showing a higher temperature.

The strait of Gibraltar
Three-channel colour composite: the cold currents along the Spanish and British coasts appear dark.

Cape of Good Hope, Cape Town
Three-channel colour composite, 8.65-µmm channel, 10.6-µm channel  and 12.05-µm channel: there are notable differences in brightness between the three channels, visible on land.