26th European Research Course on Atmospheres (ERCA) school was organized from 7th January to 3rd February 2018 by Universite Joseph Fourier and CNRS in Grenoble, France. ERCA is a high level international course on the Physics and Chemistry of atmospheres, the climate system and climate change, atmospheric pollution at different scales and the human dimensions of environmental changes. The course also covers the solar influences on the Earth's atmosphere and climate. Altogether 30 students from different countries worlwide were selected to participate in ERCA. Dr. sc. Jaša Čalogović was again invited to give students two lectures ("Solar variability influences on the climate and cosmic ray - cloud link" and "A critical look at cosmic ray - cloud link: Forbush decreases and cloud cover"). Aim of lectures was to present the influences of solar activity on climate and the possible mechanisms linking the solar activity with climate. Second lecture was focused on the cosmic ray - cloud hypothesis with aim to show several potential problems in present and past studies that analyzed climate and geophysical data using the simple correlations.