snowToyElevBands.m

%% Script to simulate the hydrograph of a changing topography

%% figure export folders
outf=['..' filesep 'figs' filesep 'eb' filesep];
mkdir(outf)

%% Model setup
A=10e6; % catchment area in sq m
zmin=2000; % elevation of the lowest elev band
zmax=3500; % elev of the top band

ft=1:365*2; % forcing time vector: two years
t=ft; % computation time vector

Tlr=-0.6e-2; % temp lapse rate in dC/m (-0.6d/100m)
Plr=0.2e-3; % precip lapse rate in m-1 (0.2 km-1)
Pmax=20e-3; % max precip rate by timestep (m)
aT=20; % temp annual amplitude in dC
mT0=10; % mean annual temp at z(1) in dC

% daily temp in dC at z(1) (sinusoid of amplitude aT, mean mT0)
T0=mT0+0.5*aT*cos(2*pi*ft/365+pi);

% daily precip rate in m at z(1) (sinusoid set to zero at 80% random dates)
P0=0.5*Pmax+0.5*Pmax*cos(ft*2*pi/365);
rng(0);
y=randsample(length(ft),0.8*length(ft));
P0(y)=0;

%% Plot options
colSnow=[0 175 234]/255;
colRain=[64 109 180]/255;
colTemp=[237 122 37]/255;
colDisch=[203 206 233]/255;
ix=(1:365)+181; % plot only 1 water year

%% increment elevation bands number

% init progress bar
reverseStr = '';

for nz=1:1:20; % nb of elev bands
    
    % band elevations linearly spaced from zmin to zmax
    z=linspace(zmin,zmax,nz);
    nzmax=length(zmax); % nb of increments
    
    gfA=zeros(1,nz); % glacier fraction area per elevation band
    
    
    %% Run model
    [P,T,swe,Qout,Qsnowtot,Qglaciertot,Qraintot,SnowMasstot,~]...
        = snowToy(A,t,ft,z,T0,Tlr,P0,Plr,gfA);
    
    %% Plot some variables
    figure(1),clf
    snowToyPlot(1,ix,A,t,P,T,Qout,SnowMasstot,colSnow,colRain,colTemp,colDisch);
    
    %% Plot topography and max annual SWE by elev band
    figure(2),clf
    snowToyStairs(2,ix,z,swe,colSnow);
    
    %% Plot SWE by elevation
    figure(3),clf
    snowToyPlotSwe(3,ix,z,t,swe)
    
    %% export figs
    saveas(1,sprintf('%ssnowToyElevBandPlot%04d.png',outf,nz))    
    saveas(2,sprintf('%ssnowToyElevBandStairs%04d.png',outf,nz))
    saveas(3,sprintf('%ssnowToyElevBandSwe%04d.png',outf,nz)) 
    
    %% Display the progress
    msg=sprintf('Percent done: %3.1f', 100*nz/20);
    fprintf([reverseStr, msg]);
    reverseStr = repmat(sprintf('\b'), 1, length(msg));
    
end