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Monday Seminar: Michael Spall - And then it sinks: ups and downs of the meridional overturning circulation

Time

16. March 2026, 10:00-11:00

Location

BCCR Seminar room 4020, Jahnebakken 5

Abstract

The global-scale meridional overturning circulation (MOC) plays an important role in the climate system by transporting heat, salt, nutrients, and other tracers across latitude circles. While waters are near the surface, air-sea fluxes exchange heat, water, carbon, and other tracers between the ocean and atmosphere, influencing weather and climate. Once removed from the surface, many of these tracers are nearly conserved following the flow, thus the MOC is an effective means to transport properties across global scales. Our understanding of the overturning circulation has developed in recent decades from both global and local perspectives. The focus of this talk will be on the local physics that concentrate vertical transports near boundaries, and non-local physics that connect surface forcing with those vertical transports. Idealized models, simple theories, and observations will be used to demonstrate these processes. Basic conservation principles are used to provide insight into the controlling physics and how the overturning in both depth space and density space depends on atmospheric forcing and environmental conditions.

 

Speaker information

BS, MS 1980, 1982, Mechanical Engineering, Clarkson College of Tech.
PhD 1988, Applied Mathematics, Harvard University
Visiting Scientist National Center for Atmospheric Research, 1988-1990
WHOI, 1990-present
Scientific interests: Application of idealized numerical and theoretical calculations to understanding
mean and low frequency variability of the general ocean circulation. Particular interests include marginal seas, mesoscale variability, Arctic Ocean.

 

Join Zoom Meeting 
https://uib.zoom.us/j/68304284910?pwd=2IgsDMWHuJlQw3XFHSTo3OoGBsRrhz.1

Meeting ID: 683 0428 4910
Password: 7pwZK4mG

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