The Cloud-AerosoL InteractionS in the Helmos background TropOsphere (CALISHTO-HELMOS Campaign) is a synergy between the PANhellenic infrastructure for Atmospheric Composition and climatEchAnge (PANACEA) Project focusing on WorkPackage 9 (WP9): Aerosol Cloud Interactions (ACI) and the European Research Council (ERC) Pyrogenic TRansformations Affecting Climate and Health (PyroTRACH) Project.
The main goal of the CALISTHO Campaign is to gain a better understanding of the processes involved in the formation and evolution of mixed-phase clouds. This is accomplished using a synergy of in situ and remote sensing instrumentation located at a unique and optimal high-altitude locations for targeted studies of aerosol-cloud interactions. We also seek to improve the remote sensing algorithms used to retrieve cloud microphysical properties, in regions of challenging topography.
The Helmos Hellenic Atmospheric Aerosol & Climate Change station (or simply Helmos Mt) is operated by the National Center for Scientific research “Demokritos” (NCSR-Demokritos). The Aroania (or Helmos) mountainous region is a unique and optimal location for targeted studies of aerosol-cloud interactions. Aroania, situated in the Achaea Prefecture of Greece and is the 3rd highest mountain in the Peloponnese (summit at 2340 m amsl.) and hosts a NCSR-Demokritos monitoring station situated at 2314 m amsl. A unique characteristic of the Helmos High Altitude Monitoring Station (2314 m, 42°N 05' 30'', 34°E 14' 25'') is that it is a typical free tropospheric background site with very low influence from the surface polluted layers (Collaud Coen et al., ACP, 2018) and lies in a cross-road of different air masses (continental, Saharan, long-range biomass burning, volcanic, etc.).