22 Apr (CLIM) Varuolo-Clarke, Western N. American Precip

Arianna Varuolo-Clarke, Dartmouth U

Exploring past, present, and future precipitation variability over western North America in the Community Earth System Model

Wed, 22 Apr, 1:30pm

Innovation Hall 131 and via Zoom (for link, email bklinger@gmu.edu)

Host: Tehreem Qureshi

My research investigates how well Earth system models capture precipitation variability – past, present, and future. We aim to elucidate the future drivers of western North American precipitation in a large ensemble of simulations from the Community Earth System Model (CESM). We quantify the thermodynamic and dynamic contributions to precipitation change across the model ensemble to isolate the relative importance of temperature-driven vs. circulation-driven changes. Then we apply a machine learning clustering algorithm to identify and quantify common patterns of projected precipitation change.

Next, I’ll present research on the recent extreme variability in the North American monsoon. Parts of Arizona, New Mexico, and northern Mexico experienced a record low monsoon season in 2020, followed by a resurgence in 2021. We evaluate CESM’s ability to simulate such large interannual swings across a hierarchy of model ensembles spanning multiple versions of CESM.