# Defining the central longitude in Arctic borders in the Arctic Mapping Tool

5 views (last 30 days)
Ashfaq Ahmed on 5 Dec 2023
Commented: Ashfaq Ahmed on 5 Dec 2023
Hi! I am curretnly using ArcticMappingToolbox to plot the Arctic borders. But automatically it uses 45°W as the central longitude (based on the NSIDC stereographic system). Like in this figure -
But I want the 0* to be the central longitude like this -
Can anyone please help me with either a) how can I rotate the arcticborders.m function? or b) create a stereographic grid that has 0* as central longitude?
Ashfaq Ahmed on 5 Dec 2023
@Dyuman Joshi I meant, as you can see from the 2nd plot, the figure it 45° offset. I want to do that. I want to plot like Figure 2 in my figure 1.
Dyuman Joshi on 5 Dec 2023
You mean the plot, not the function, ok.

Chad Greene on 5 Dec 2023
Try this. Into the Command Window type
open arcticborders
Then find the line where it loads the border data. Try adding this right after that line:
for k = 1:177
% unproject:
[lat,lon] = psn2ll(x{k},y{k});
% reproject:
[x{k},y{k}] = ll2psn(lat,lon,'meridian',0);
end
Ashfaq Ahmed on 5 Dec 2023
Ok, I think I got it, it worked
%% Plot
for k = 1:177
% unproject:
[lat,lon] = psn2ll(x{k},y{k});
% reproject:
[x{k},y{k}] = ll2psn(lat,lon,'meridian',0);
end
hold on
if faceplot
n = 1;
for k = 1:177
xk = x{k};
yk = y{k};
nanz = [0,find(isnan(xk))];
for kk = 1:length(nanz)-1
h(n) = patch(xk(nanz(kk)+1:nanz(kk+1)-1),yk(nanz(kk)+1:nanz(kk+1)-1),.5*[1 1 1],varargin{:});
n=n+1;
end
end
else
h = plot(cell2mat(x),cell2mat(y),varargin{:});
end
Ashfaq Ahmed on 5 Dec 2023
Thank you so much!!!