Variability and predictability of cold-season atmospheric river activity over the North Atlantic ...

• Main Author: Li, Chuxuan
• Format: Text
• Language: English
• Published: The University of North Carolina at Chapel Hill University Libraries 2020
• Subjects: North Atlantic
• Online Access: https://dx.doi.org/10.17615/mq34-cc70; https://cdr.lib.unc.edu/concern/dissertations/jd473342d

Atmospheric rivers (ARs) are conduits of enhanced water vapor transport in the lower troposphere and cause extreme precipitation and flooding events in many regions. This thesis explores the variability and predictability of North Atlantic (NA) AR activity using a set of large-ensemble atmospheric simulations and observations. In the first part, we depict three leading modes governing sea surface temperature-forced variability in AR occurrence frequency via an empirical orthogonal function analysis. We then characterize their spatiotemporal variations, determine their physical mechanisms, and link them to large-scale modes of climate variability. We also identify the regions where seasonal AR occurrence has relatively high or low predictability. In the second part, we divide NA ARs into four distinct clusters based on their genesis locations and trajectories, and for each cluster identify the large-scale climate modes controlling the year-to-year variations in its population and the regions vulnerable to its ...