NSF Award
2420300
Sea ice in the Southern Ocean around Antarctica is intricately linked to ecosystems and the global climate, and it appears to be on the brink of rapid change. Recent unexpected decreases in Antarctic sea ice have been partly attributed to ocean heat release, which may be influenced by variations in freshwater input, turbulent ocean mixing, and internal system feedbacks. Studying how these factors modulate the growth and melt of sea ice has been challenging due to the remoteness of the Southern Ocean and its blanket of winter sea ice. This research will combine observations and modeling to quantify the impacts of episodic snowfall and storms on the Antarctic snow-ice-ocean system. The results will contribute to a clearer understanding of ongoing and future changes in Antarctic sea ice, enabling better projections of global ocean circulation, carbon uptake, and ecosystem health.<br/><br/>The primary goal of this work is to characterize the time evolution of the Antarctic sea ice mass budget and upper ocean properties following perturbations from snowfall and storms. Composite analyses of autonomous Argo profiling float measurements, atmospheric reanalysis data, and satellite remote sensing will be used to illuminate the competing processes these events set in motion, which can include snow-ice conversion, basal sea ice melt, and trapping of wind-blown snow in sea ice cracks, known as leads. A new one-dimensional coupled ice-ocean model configuration will be developed and used for sensitivity experiments that isolate impacts and feedbacks. These findings will be applied to trends in key variables diagnosed in global climate models to explore the consequences of changes in Southern Hemisphere storm tracks and snow accumulation expected in a warming climate. Broader impacts of this project include mentoring and teaching in educational programs that expand participation in the earth sciences and hosting a workshop to enhance writing skills for local climate advocacy.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
