Friday, October 31, 2025 - 3 p.m. to 4 p.m.
DeMeritt Hall - Room 240
Title: Nor'easters, Hurricanes, storm surge & the Earth's rotation
Presenter: James Pringle, Professor – Earth Sciences Department - UNH
Host: Per Berglund, Professor – Physics & Astronomy Department - UNH
Abstract:
With increasing frequency, winter storms in New England have created damaging floods -- "storm surges." Existing estimates of the magnitude of this flooding have been based on Hurricanes, and these estimates do not perform well when used to predict the damaging winter time storm surges in New England. These high water events are driven by Nor'easters, extra-tropical cyclones that move along the coast and bring rain, snow and flooding to New England.
To understand why Hurricanes and Nor'easters differ, we need to understand the role of the Earth's rotation and the paths of these storms, and how they interact to drive coastal flooding. The dynamics we examine are important from coastal oceans and mid-latitude storms in the atmosphere to accretion disks around black holes and young stars.
Estimates for the relative magnitude of storm surge are developed for these storms, and it is found that storms moving parallel to the coast but somewhat offshore can drive very large and long lasting flooding, and that this flooding is caused primarily by the alongshore winds. We show that similar patterns hold for the most damaging historical flooding events driven by hurricanes along the same coastline.
