parameters.py

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## 			 FIXED PARAMETERS   			     ##
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'''
Author: T. Kent  (amttk@leeds.ac.uk)
List of fixed parameters for model integration and EnKF.
'''

import numpy as np

''' MODEL PARAMETERS '''

Neq = 3     # number of equations in system (3 with topography, 4 with rotation_
L = 1.0     # length of domain (non-dim.)

Nk_fc = 200                                 # forecast resolution
dres = 4                                     # refinement factor for truth gridsize
Nk_tr = dres*Nk_fc                           # truth resolution

cfl_fc = 0.5 # Courant Friedrichs Lewy number for time stepping
cfl_tr = 0.5

Ro = 'Inf'          # Rossby no. Ro ~ V0/(f*L0)
Fr = 1.1            # froude no.
g = Fr**(-2) 		# effective gravity, determined by scaling.
A = 0.1
V = 1.

### threshold heights
H0 = 1.0
Hc = 1.02
Hr = 1.05

### remaining parameters related to hr
beta = 0.2 #controls
alpha2 = 10 #controls strength of removal from the system
c2 = g*Hr #controls strength of convective downdraft
cc2 = 0.1*c2

### BCs
BC = 1 #periodic
# BC = 2 #outflow (Neumann BCS with derivative=0 at boundaries)
# BC = 3 #specified inflow at x = 0 (Dirichlet), outflow at x = L.
# NOTE when BC=3: to specify inflow, see step_forward routine in f_modRSW.py


''' FILTER PARAMETERS '''

n_ens = 20                              # number of ensembles
Nmeas = 6                               # number of cycles
tn = 0.0                                # initial time
dtmeasure = 0.144                       # ~ 1 hr in nondimensional time (L ~ 500km and V ~ 20m/s implies T ~ 25000s ~ 6.94hrs)
tmax = Nmeas*dtmeasure
tmeasure = dtmeasure
assim_time = np.linspace(tn,tmax,Nmeas+1) # vector of times when system is observed
#
sig_ic = [0.05,0.05,0.0]                # initial ens perturbations [h,hu,hr]
ob_noise = [0.1,0.05,0.005]            # ob noise for [h,hu,hr]
o_d = 50                                # ob density: observe every o_d elements
#

''' OUTER LOOP'''
'''
Parameters for outer loop are specified in main_p.py
loc     : localisation scale
add_inf : additive infaltaion factor
inf     : mult. inflation factor
'''

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#			END OF PROGRAM				 #
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