Do atmospheric rivers trigger tabular iceberg calving?

Abstract The processes governing iceberg calving from ice shelves remain poorly understood. Recent studies suggest that anomalous atmospheric moisture transport events – atmospheric rivers – can act as triggers for calving. These conclusions, however, were based on studies of case studies of individual icebergs or ice shelves, making it difficult to determine if this relationship remains apparent when considering a wider set of calving events and ice shelves. Here, we assemble an Antarctic-wide catalog of tabular iceberg calving events to evaluate whether a significant correlation exists between calving and enhancement of total and meridional integrated vapor transport (IVT), a measure of atmospheric moisture transport. We find that ~80% of the calving events in our study occur when metrics of IVT are less than the 90th percentile of their monthly climatologies. However, the remaining ~20% of calving events that occur during periods with short-term enhanced IVT exhibit a statistically significant correlation. The results, however, are regionally dependent, with a statistically significant correlation between enhanced IVT and calving in the Antarctic Peninsula and none in the Amundsen Sea Embayment. This suggests that, although enhanced IVT is not a primary control on the iceberg calving process, enhanced IVT may play a role in triggering calving events under certain conditions.