The Hidden Cooling Potential of Atmospheric Ice Clouds

Ice clouds are common in the Earth’s upper atmosphere and are often the first solid objects that incoming sunlight encounters. They play a crucial role in the planet’s energy balance, yet the magnitude — and in some cases even the sign — of their effect on Earth’s climate remains uncertain. Unlike spherical water droplets, ice crystals exhibit a wide variety of shapes, making it challenging to predict how they scatter and reflect sunlight.

In this talk, I will present airborne measurements of ice crystal shapes and their optical properties. For the first time, such direct optical measurements allow us to test and develop observationally-based parameterisations for climate models, improving our ability to quantify how ice clouds affect sunlight reflection and contribute to planetary cooling. At the end, I will outline future research directions in the Atmospheric Physics group at the University of Wuppertal, aimed at advancing our understanding of how atmospheric particles interact with electromagnetic radiation, with applications ranging from air pollution monitoring to satellite remote sensing.