function plot_coastlines(mesh,varargin);

if nargin==2, 
	if strcmpi(class(varargin{1}),'pairoptions'),
		options=varargin{1};
	end
else
	%process options: 
	options=pairoptions(varargin{:});
end

%retrieve some variables: 


load ./Data/coastlines
[x,y,z]=AboveGround(coastlat,coastlon,mesh.r(1),1000);
hold on, p=plot3(x,y,z,'k-'); 
set(p,'Color',getfieldvalue(options,'coast_color','k'));
set(p,'LineWidth',getfieldvalue(options,'coast_linewidth',1));