Updating existing submodules

First clone the glm-and repo:

git clone --recurse-submodules https://github.com/AquaticEcoDynamics/glm-aed.git

Then enter the glm-aed directory, update and push:

cd glm-aed
git submodule update --remote
git add .
git commit -m 'updating submodule X and X'
git push

Note that this will require appropriate authentication for the push to be successful.