The main scope of this activity was to foster the exchange of expertise between the European Lidar Network (EARLINET) and Latin America Lidar Network (LALINET), and demonstrate the capability of joint research, setting the groundwork for GALION (The Global Atmosphere Watch Aerosol Lidar Observation Network) and future calibration/validation of ESA’s atmospheric satellite missions such as Aeolus and EarthCARE. During the activity, transfer of knowhow from European research groups to the Latin America lidar research network took place in the area of harmonised measurement and data handling protocols for addressing global science questions related to atmospheric aerosols.

APEL paved the way for a continued future cooperation as follows:

• The LALINET stations in Brazil will continue to implement the quality assurance programme and use the single calculus chain data processing tool, and in parallel transfer the knowhow to other LALINET members.
• Part of the quality assurance and instrument optimisation activities will continue even with limited support.

The activities carried out during the APEL campaigns will be the backbone for future global calibration/validation activities that involve the use of ground-based aerosol lidar instruments as validation tools for the aerosol products from ESA’s Earth observation lidar missions. Furthermore, the data analysis will be applied further to collected measurement datasets from ground- and space-based lidars to address aerosol science questions.