Monday, 8 July 2019
Dr David Stevens
School of Mathematics
University of East Anglia
"Modelling exoplanetary oceans and climates"
Exoplanets are planets that orbit stars other than our own Sun. Before 1995 there were no confirmed exoplanets. As of now, over 4000 exoplanets have been discovered. The ocean plays a key role in the climate of Earth, and it is therefore expected that any oceans present on an exoplanet would also be a crucial component of the climate system and hence have implications for the habitability of the planet. However, planetary and oceanic properties cannot be assumed to be the same on an exoplanet as on Earth, and therefore the role of the ocean in exoplanetary climates cannot be assumed. Here the role of two key properties are examined. The effect of ocean salinity, at a level both higher and lower than on Earth, is explored and reversal of the Earth-like meridional overturning circulation is found. The impact of planetary rotation period is also investigated, and it is concluded that a longer rotation period results in a greater poleward ocean heat transport, shallower thermocline depth, increased horizontal ocean velocities, and stronger overturning circulation. Finally, a coupled atmosphere-sea ice-ocean model of a tidally locked exoplanet is presented. The extent of the zonal circulation and magnitude of the zonal heat transport is found to have significant dependence on the location of a meridional barrier in the ocean, with resulting dark side mean temperatures varying by over 7oC.
WHEN: Monday 8 July 2019
WHERE: Room 314, Science 3 Building
TIME: 3.00 pm–4.00 pm
All interested are welcome to attend
Light refreshments to follow in Common Room