SMS scnews item created by Georg Gottwald at Sun 22 Oct 2017 1604
Type: Seminar
Modified: Thu 26 Oct 2017 1700
Distribution: World
Expiry: 5 Nov 2017
Calendar1: 27 Oct 2017 1600-1700
CalLoc1: Carslaw 275
CalTitle1: Sydney Dynamics Group: Tangent-space splittings for data assimilation
Auth: gottwald@cpe-101-175-198-183.lnse8.ken.bigpond.net.au in SMS-auth

Sydney Dynamics Group: Jason Frank (Utrecht) -- Tangent-space splittings for data assimilation

Dear All, 

This week on Friday, October 27, Jason Frank (Utrecht), will give a talk at USyd,
Carslaw Lecture Theatre 275 at 4pm on 

Title: Tangent-space splittings for data assimilation 

Abstract: Data assimilation methods are used for marrying instrumental observations of a
physical system to numerical prediction models.  There are many flavors, depending on
whether one takes a probabilistic/statistical, control theoretic, or dynamical systems
point of view.  Furthermore there are variational methods that consider a whole time
window and sequential methods that proceed step-by-step.  In this talk I will consider
the relationship between the observation operator and the decomposition of the model
tangent space in terms of Lyapunov exponents/vectors.  The main conclusion is that the
observations should constrain the unstable tangent space.  Using this point of view we
construct two methods, one variational and one sequential and illustrate their
convergence behavior.  Along the way I will mention some other structural considerations
in data assimilation.  

Hope to see you all there, 

Georg