m = Basemap(projection='cyl')
m.drawcoastlines(linewidth=0.4)
m.drawmeridians(np.arange(-180.0, 181.0, 30.0), color='silver', linewidth=0.4)
m.drawparallels(np.arange(-90.0, 91.0, 30.0)  , color='silver', linewidth=0.4)
plt.show()