Adding High Resolution basemap to Geographic Bubble Chart

Hi,

From: https://www.mathworks.com/help/matlab/creating_plots/_mw_47bfdfc1-09dc-40c2-82c6-280c83609dd8.html

 'To use another basemap, you must have an Internet connection or you must have previously 
 downloaded the basemaps from MathWorks.'

Wondering if anyone knows how to create/add a high-resolution (Etopo1?) basemap to Geographic Bubble Chart?

Working on small equatorial islands and atolls, the highest the resolution the better.

Thanks!