Abstract ID: 3.12487 | Accepted as Talk | Talk/Oral | TBA | TBA

The impact of climate change on cloud properties and cloud occurrence remains an area of active research. To enhance our understanding and improve cloud representation in climate models, the Aerosol, Clouds and Trace Gases Research Infrastructure (ACTRIS) has established the Topical Center for Cloud In Situ Measurements (CIS). The mission of ACTRIS-CIS is to develop a monitoring network for key cloud properties, in conjunction with the Centre for Cloud Remote Sensing, ensuring comprehensive observation of cloud amount, altitude, and opacity. The European Centre for Cloud Ambient Intercomparisons (ECCINT), hosted at the Sonnblick Observatory (SBO) in Austria, is part of the ACTRIS Topical Centre for Cloud In Situ measurements (CIS) being responsible for implementing the cloud physical parameters such as Cloud Liquid Water Content (LWC) and Cloud Effective Radius (Reff). The focus is particularly on LWC, a central variable for the water cycle, weather forecasts and climate models. LWC not only influences the probability of precipitation and the redistribution of water between the atmosphere and the surface, it also plays a major role in determining cloud properties and thus their influence on temperature, radiation and precipitation. LWC data improves simulations of global warming and precipitation patterns in long-term climate projections, but also in weather forecasts. As part of the Austrian geological, geophysical, climatological and meteorological service, GeoSphere Austria, the Sonnblick Observatory conducts regular cloud in situ intercomparisons with all relevant and new developed cloud probes to ensure the comparability of various measurements at European sites and improve the understanding of cloud-aerosol interactions. During two international field studies in 2022 and 2024, the focus was on capturing the cloud physical base parameters of liquid water content and effective radius. The aim of these measurement campaigns was to compare different observation techniques to develop and improve Standard Operating Procedures (SOPs) for ACTRIS. Here we present an overview of all ECCINT related activities within ACTRIS and the European Cloud In Situ community as well as out coming results and conclusions of our intercomparison campaigns for cloud droplet probes at Sonnblick Observatory.