Although mountainous regions form only about a quarter of the land area, they influence a large part of the Earth. From a climatological perspective, they modulate atmospheric circulation, radiation and water balance and are therefore sensitive indicators of changes in the climate system at different scales. To deepen our knowledge of the peculiarities of the climates of cold regions (high mountains and poles), we combine in-situ measurements with modern modeling approaches. Thus, we can identify and quantify drivers, processes and impacts of climate change in mountainous regions. The goal is thus to contribute to an improved understanding of global change - one of the greatest challenges of our future.