Land and Climate Seminar - Adventures in terrestrial cryospheric data assimilation

Speaker: Kristoffer Aalstad

In this talk I will provide a guided tour of our adventures applying data assimilation to various terrestrial cryospheric problems. While the focus will primarily be on seasonal snow, I will also present some related developments for glacier and permafrost modeling. The role that targeted terrestrial cryospheric reanalysis can play in filling key observational gaps from both established and emerging Earth observations will be a recurring theme. This will be highlighted through examples from some ongoing work on trying to estimate global seasonal snow water equivalent using optical satellite data. Throughout the talk, I will provide several examples of combining machine learning and data assimilation to both speed up and enhance inference. Moreover, I will introduce some recent forays into hybrid and adaptive particle schemes as well as some experimental work on ensemble-based hierarchical inference. Through our adventures, I hope to showcase the still largely untapped potential that data assimilation holds for adding value to observations and constraining model uncertainty across a broader range of problems.