What Processes Drive Southern Ocean Sea Ice Variability and Trends? Insights from the Energy Budget of the Coupled Cryosphere-ocean-atmosphere System

The key scientific question of this project is: what mechanism is the dominant driver of Southern Ocean (SO) sea ice variability and long-term trends in nature? Our primary goal is to understand the processes that drive SO sea ice loss over the observational record and identify which models get the physics right. Although our primary focus is on mechanisms of long-term sea ice loss, the observational record includes rich information at shorter timescales which are better sampled and may elucidate the relevant physics. Thus, our analysis of mechanisms of sea ice variability spans time scales ranging from days (synoptic) to inter-annual variability to long-term trends to identify model biases in the physics that drive SO sea ice loss events. We divided our work into explorations of 5 major topics 1. Identifying model biases in high frequency sea ice variability in the Southern Ocean 2. Identifying model biases in radiative impact of sea ice loss events 3. Disentangling the roles of winds and sea surface temperature on the observational record of Southern Ocean sea ice 4. Quantifying the degree to which Southern Ocean sea ice loss is remotely forced by the influence of the tropics and mid-latitudes and, conversely, how much much influence does the Southern Ocean have on the tropics 5. Analyzing the impact of atmospheric heat transport on sea ice loss