Observations and Modelling of Fronts and Frontogenesis

divergence in the mixed layer and convergence in the
interior, resulting in upwelling of isopycnals near the
coast. The horizontal scale over which this upwelling occurs
adjusts dynamically according to (28).
were,
The initial conditions for the cases reported on here
h10 - 0.5 [17m] , h20 = 1.0 [33 ml,
ulO=u20=u30=O,
with total depth H = 10 [330 m] and density differences,
Case 1: 2l - 1000 [0.3 kg m3],
(38)
32 - 100 [0.03 kg m3] , (39a)
Case 2: 2l = 5000 [1.5 kg m3],
'32 = 500 [0.15 kg m3] , (39b)
Case 3: 2l 10000 [3 kg m3],
32 = 1000 [0.3 kg m3]. (39c)
In all cases, the forcing was constant,
r = - 1 [0.1 N m2], Q 1 [75 W m2], (40)
and the total depth H 10 [330 ml. In the following
discussion, we focus on Case 1. When dimensional values
depend on the density differences, we give only the
dimensional values corresponding to Case 1.
Initially, when the layer depths and density differences
are independent of y and the geostrophic velocities vanish
identically, the system (28) with (17) may be solved