John Marshall

Cecil and Ida Green Professor of Oceanography, MIT

A realtime observatory for laboratory simulation of planetary flows

A realtime observatory for laboratory simulation of planetary flows.

(Ravela, Sai and Marshall, John and Hill, Chris and Wong, Andrew and Stransky, Scott), EXPERIMENTS IN FLUIDS, vol. 48, no. 5, pp. pages, 2010.


Motivated by the mid-latitude atmospheric circulation, we develop a system that uses observations from a differentially heated rotating annulus experiment to constrain a numerical simulation in real-time. The coupled physical-numerical system provides a tool to rapidly prototype new methods for state and parameter estimation, and facilitates the study of prediction, predictability, and transport of geophysical fluids where observations or numerical simulations would not independently suffice. A computer vision system is used to extract measurements from the physical simulation, which constrain the model-state of the MIT general circulation model in a hybrid data assimilation approach. Using a combination of parallelism, domain decomposition and an efficient scheme to select ensembles of model-states, we show that estimates that effectively track the fluid-state can be produced. To the best of our knowledge, this is the first real-time coupled system for this laboratory analog of planetary circulation.

doi = 10.1007/s00348-009-0752-0