Contour plot with polar stereoghapic projection in north hemispehere above 60 degree latitude

Hi,

I have ut(24), lat(24) and z (24x24); data attached as .mat. I want to plot a contour plot in polar stereographic projection for northern hemisphere above 60 degree latitude (something like attached ). I tried with m_map polar sterographic projection.

m_proj('stereographic','lat',90,'long',30,'radius',60);
m_elev('contour',[0:0.00009:1],'edgecolor','b');
m_grid('xtick',12,'tickdir','in','ytick',[60:10:90],'linest','-');
m_coast('linewidth',1,'linestyle','-','color','k');

I got the image as completely different.

I also tried using like https://jp.mathworks.com/matlabcentral/answers/170145-how-to-plot-contourf-data-on-m-map-polar-stereographic-projection, the plot it is not in sterographic projection. Can anyone help.

Answer 1

[Milan Bansal]

Hi Madan Kumar

It looks like you're on the right track with using the m_map toolbox for polar stereographic projection. However, the code you provided seems to use m_elev and m_coast, which are for elevation data and coastline plotting, respectively, and may not apply directly to your data.

To contour plot your ut, lat, and z data correctly in a polar stereographic projection, try modifying your approach as shown in the sample code snippet below:

load('poldata.mat')
% Polar stereographic projection using m_map
m_proj('stereographic', 'lat', 90, 'long', 0, 'radius', 30);  % Stereographic projection, centered at north pole

% Convert latitudes and UT into a meshgrid
[Lat, UT] = meshgrid(lat, ut);

% Plot the contour using m_contourf for filled contours
m_contourf(UT, Lat, z, 'LineStyle', 'none');

% Optional: Add a coastline (this might not be needed for your plot)
m_coast('line', 'color', 'k');

% Add grid lines and labels
m_grid('xtick', 12, 'tickdir', 'in', 'ytick', [60:10:90], 'linestyle', '-');

% Add colorbar for reference
colorbar;

Please refer to the following link for more information : https://www.eoas.ubc.ca/~rich/mapug.html

Hope this helps!