Since the Japanese satellites ADEOS-1 and ADEOS-2 were lost in June 1997 and October 2003, with each a POLDER instrument onboard, PARASOL offers a new opportunity for the climate change research community to take advantage of the POLDER original instrument concept. The instrument was designed by the Atmospheric Optics Laboratory (LOA). It includes :

• a digital camera with a 274 x 242-pixel CCD sensor array,
• a wide-field telecentric optics,
• a rotating wheel.

The instruments makes measurements at different wavelengths (443, 490, 565, 670, 763, 765, 865, 910 and 1020 nm) and in several polarization directions. Spectral responses are available for POLDER1, POLDER-2 and PARASOL. Since it acquires a sequence of images every 20 seconds, the instrument can view ground targets from different angles. Compared to POLDER, the PARASOL sensor array was rotated 90 degrees to favor multidirectional observation over daily global coverage. Likewise, a 1020 nm channel was added to make measurements to compare to data acquired by the lidar onboard CALIPSO.

POLDER rotating wheel

POLDER instrument

POLDER spectral response