The high variability of tropospheric aerosols, both in
space and time, is the main cause of the high uncertainty
about radiative forcing related to tropospheric aerosols
and their interaction with clouds. Because of the lack of
high resolution aerosol global vertical profiles, the
vertical mixing has not been considered so far in studies
of spatial and temporal variability. The CALIPSO
mission provides the first opportunity to investigate the
4-D aerosol and cloud fields in detail. However, because
of the CALIOP small footprint and the revisit time of 16
days, correlative ground-based lidar observations are
necessary in order to investigate the representativeness
of these satellite observations. EARLINET, the
European Aerosol Research Lidar Network, started
correlative measurements for CALIPSO in June 2006,
right after the CALIPSO launch. An integrated study of
CALIPSO and EARLINET correlative measurements
opens new possibilities for spatial (both horizontal and
vertical) and temporal representativeness investigation
of polar-orbit satellite measurements also in terms of
revisit time.Postprint (published version