What is the radiative impact of clouds and aerosols on our planet? This question is one of the principal unknowns limiting our understanding of the climate system, and the focus of study for several large-scale research programmes.

The Calipso mission, which CNES is pursuing in collaboration with NASA, aims to provide global, curtain-like vertical profiles of the atmosphere at a resolution of 30 m starting by end of 2005. By determining the geographic location, altitude and optical properties of cloud layers and aerosols, Calipso helps scientists to gain a closer understanding of how they shape climate processes. After 2 years orbiting Earth, Calipso has delivered the expected results and its measurements are becoming the benckmark for climate models.

Calipso and its companion microsatellite Parasol are part of the A-Train that is the first US-French observatory in orbit.

^{Last updated: March2009}