NP3	Geophysical turbulence and diffusion
		.2	Balance in atmosphere-ocean dynamics I

Convener: Neven, E.C.
Co-Convener(s): Sommeria, J.
Tuesday, 20 April 1999
Lecture Room: Paulus Potterzaal 2
Chairperson: Nycander, J.

Numerical algorithms and simulations

08:45	LELONG, M.-P.
		Adjustment in fluids. Part I: cyclostrophic balance in non-rotating fluids

09:00	LELONG, M.-P.
		Adjustment in fluids. Part II: geostrophic balance in rotating fluids

09:15	IACONO, R.; RONCHI, C.; STRUGLIA, M.V.; PISACANE, G.
		Cubed sphere numerical solutions of the shallow water
		equations in spherical geometry

09:30	ISHIOKA, K.; YAMADA, M.; HAYASHI, Y.-Y.; YODEN, S.
		Two-dimensional turbulence on a rotating sphere
		with the spectral code ISPACK

09:45	KEPPENS, R.; TOTH, G.
		The Kelvin-Helmholtz instability in magnetohydrodynamics:
		multi-dimensional simulations with the Versatile Advection Code

10:00	FARGE, M.; SCHNEIDER, K.
		Wavelet approach for 2D Navier-Stokes equations: analysis and modelling

10:15	SCHNEIDER, K.; FARGE, M.
		Wavelet approach for 2D navier-stokes equations: simulations

10:30	BREAK

Chairperson: Nycander, J.

11:00	HAUPT, R.L.; HAUPT, S.E.
		Introduction to genetic algorithms

11:15	HAUPT, S.E.; HAUPT, R.L.
		Using genetic algorithms to find equilibrium solutions
		in geophysical fluid dynamics

11:30	DRITSCHEL, D.G.; POLVANI, L.M.; MOHEBALHOJEH, A.R.
		The contour-advective semi-Lagrangian algorithm
		for the shallow-water equations (Oral + Poster)

Balanced models, adjustment

11:45	MOHEBALHOJEH, A.R.; DRITSCHEL, D.G.
		On the degree of balance in numerical models of the shallow water equations

12:00	NEVEN, E.C.
		Families of direct inversion balanced models on a hemisphere

12:15	KUO, A.C.; POLVANI, L.M.
		Nonlinear geostrophic adjustment, asymmetry,
		and irreversible potential vorticity change

12:30	LUNCH & POSTERS
Chairperson: Sommeria, J.

14:30	FORD, R.; MCINTYRE, M.E.; NORTON, W.A.
		Balance and the slow quasi-manifold. Part 1: spontaneous adjustment
		emission and the fuzziness of the flow quasi-manifold

14:45	FORD, R.; POLVANI, L.M.
		Balance and the slow quasi-manifold. Part 2: Interaction between
		Rossby waves and inertion-gravity waves at small Rossby number

15:00	GURARIE, D.
		Wave-vortex interaction and balanced model for rotating shallow water

15:15	NICOLAENKO, B.; MAHALOV, A.
		A numerical study of an operator splitting method for rotating
		flows with large ageostrophic initial data

15:30	MAHALOV, A.; NICOLAENKO, B.
		Asymptotic regimes of 3D rotating Euler-Boussinesq equations

Data-assimilation, initialization

15:45	MACHENHAUER, B.
		Initialization. Part 1: Machenhauer and Baer-Tribbia
		balance in shallow water odels

16:00	MACHENHAUER, B.
		Initialization. Part 2: extensions to multi-level,
		diabatic primitive equation models

16:15	MEDVEDEV, S.B.
		Initialization for a regional atmospheric model with
		the application of variational method

16:30	BREAK

Chairperson: Sommeria, J.

17:00	DALEY, R.
		Balance in DATA Assimilation Systems (Solicited Paper)

17:30	TALAGRAND, O.
		Variational assimilation and diabatic initialization

17:45	BARKMEIJER, J.
		Singular vectors and the analysis error metric

18:00	GRIFFITH, A.K.; MARTIN, M.J.; NICHOLS, N.K.
		Treating model error in 3D and 4D variational data assimilation

Chairperson: Neven, E.C.

18:15	Discussion on aim, programme, and future direction of the
		"Balance in Atmosphere-Ocean Dynamics" session

18:30	END OF PART I

NP3	Geophysical turbulence and diffusion
		.2	Balance in atmosphere-ocean dynamics II

Convener: Neven, E.C.
Co-Convener(s): Sommeria, J.
Wednesday, 21 April 1999
Lecture Room: Paulus Potterzaal 2
Chairperson: Montgomery, M.T.

Potential vorticity, hydrostatic balance

08:30	MCINTYRE, M.E.
		Balance, PV invertibility, and Lighthill radiation (Solicited Paper)

09:00	LI, Y.; BATES, J.R.; RUGE, J.; BRANDT, A. MCCORMICK, S.F.;
		MENARD, R.; RIISHOJGAARD, L.P.; COHN, S.E.; ROOD, R.B.
		Approximate PV approaches in modelling (pseudo-PV)
		and data assimilation (proxy-PV)

09:15	VAN DEN DOOL, H.M.; BRUNET, G.
		Use of reanalysis isentropic potential vorticity data sets
		in empirical forecast models

09:30	TRIELING, R.R.; VERKLEY, W.T.M.
		Contour dynamics simulations of observed synoptic developments

09:45	APPENZELLER, C.
		Potential vorticity, the tropopause and stratospheric ozone

10:00	VAN DELDEN, A.
		The linear dynamics of hydrostatic adjustment in the atmosphere

10:15	MONTGOMERY, M.T.
		Balance dynamics in hurricanes: on the applicability of hydrostatic and
		gradient balance approximations in hurricanes and a three-dimensional
		generalization

10:30	BREAK

Chairperson: Montgomery, M.T.

Elimination of fast variables, semi-geostrophic balanced models

11:00	VAN KAMPEN, N.G.
		Elimination of fast variables in systems with two time scales (Solicited Paper)

11:30	LYNCH, P.
		The swingin' spring: a simple model of balance in the atmosphere

11:45	CULLEN, M.J.P.
		The semi-geostrophic approach to balance: Part 1

12:00	CULLEN, M.J.P.
		The semi-geostrophic approach to balance: Part 2

12:15	DOUGLAS, R.J.
		Defining a transformation for semigeostrophic theory on
		a sphere via energy minimisation

12:30	LUNCH & POSTERS

Chairperson: Bokhove, O.

Hamiltonian balanced models

14:30	ROULSTONE, I.
		On Hamiltonian balanced models: constraints and velocity-splitting

14:45	WUNDERER, C.; MOHEBALHOJEH, A.R.
		On Hamiltonian balanced shallow-water models

15:00	THEISS, J.
		Hamiltonian balanced models for three-dimensional stratified flow

15:15	WINGATE, B.; HOLM, D.
		Nonlinearly dispersive Euler-Poincare equations for shallow water dynamics

15:30	NORE, C.; SHEPHERD, T.G.
		A Hamiltonian weak-wave model for shallow-water flow

15:45	BOKHOVE, O.
		Variational formulation and balanced models
		for hydrotatic flows (Oral + Poster)

16:00	BAIGENT, S.; NORBURY, J.
		A class of Hamiltonian balanced models whose balanced
		states are constrained optima

16:15	BREAK

Chairperson: Bokhove, O.

Coherent structures, balance and stability

16:45	GRIMSHAW, R.
		Coherent structures and gravity waves: part 1; radiating solitary waves

17:00	GRIMSHAW, R.
		Coherent structures and gravity waves: part 2; models for slow manifolds

17:15	KNOX, J.A.
		Nonlinear balance and inertial stability relationships re-examined

17:30	KIRWAN, A.D.
		A synopsis of mostly surface kinematic characteristics of ocean vortices

17:45	BENILOV, E.S.
		On the evolution of a near-surface lens in a two-layer ocean on the beta-plane

18:00	SKIBA, Y.N.
		Spectral approximation in the linear stability study of viscous flows on a sphere

18:15	NYCANDER, J.
		Maximum energy states in balanced models

18:30	BOUCHET, F.; ROBERT, R.; SOMMERIA, J.
		Statistical equilibrium in shallow water and stratified systems

18:45	NAUTA, M.D.
		2D-vortices and accretion disks

19:00	END OF SUB-SESSION