Cloud physics is an outstanding problem for Earth, Solar System planets, and exoplanets, from the sub-micron scales of cloud formation to the global scale of atmospheric dynamics. Indeed, our limited understanding of how cloud physics changes with warming is the primary cause of physical uncertainty in projections of Earth's climate. Studying clouds across planetary regimes between the Solar System and exoplanets provides us with a lever arm to improve our understanding of the fundamental physics of clouds. This includes processes ranging from cloud formation, growth and transport, and the resulting effects of clouds on the top-of-atmosphere radiative budget (i.e., the climate). Given the recent first detections of mineral clouds on gas giant exoplanets with JWST, current and upcoming Solar System missions to Jupiter, Venus, and Mars, and the ever-pressing need to understand Earth's changing climate, it is imperative to link together our disparate understanding of cloud physics across disciplines and develop a coherent understanding.

The goal of this program is to connect cloud physicists who study Earth, other Solar System objects (Venus, Mars, Titan, and gas and ice giants), and exoplanets. We aim to make advances through combining the expertise of laboratory experimentalists, observers (both in situ and remote), theorists, and numerical modellers to understand the interaction of cloud formation and growth, transport, and the radiative feedback of clouds on the resulting climate and atmospheric dynamics across the broad range of possible planetary regimes.