Arctic sea ice is rapidly declining, threatening global climate stability, ecosystems, regional communities, and more. Marine Cloud Thinning (MCT) and Marine Cloud Brightening (MCB) have been proposed as potential intervention strategies to cool the Arctic and protect sea ice. To responsibly evaluate these approaches, we must first understand when, where, and to what extent Arctic clouds influence the surface energy budget over sea ice. This project will provide foundational knowledge on these processes.

The proposed research will quantify the first-order susceptibility of Arctic sea ice to cloud perturbations by examining how supercooled, liquid-containing, stratiform clouds affect the full surface energy budget across seasons and environmental conditions. Historical high-quality observations from two, year-long expeditions will anchor the analysis, providing the most reliable characterization available of cloud properties and their energetic effects over sea ice. To scale these insights across the various surfaces of the pan-Arctic region and throughout the year, we will evaluate and utilize an advanced regional model. By benchmarking model performance against observed process relationships, the project will create monthly maps of supercooled liquid-containing cloud occurrence and surface energy susceptibility, delivering a robust, observation-constrained framework for assessing Arctic MCT and MCB feasibility. 

This work will clarify seasonal windows and geographic zones where MCT or MCB may or may not be effective, distinguishing the conditions that limit intervention potential from those where meaningful action may be plausible. The project poses minimal risk, generates critical scientific understanding of cloud-cryosphere interactions, and directly informs future research directions, model development, and policy-relevant evaluation of climate intervention strategies in the Arctic.