https://www.scientificamerican.com/article/mountain-glaciers-are-major-contributors-to-rising-seas/

Melting mountain glaciers could account for nearly a third of the sea-level rise that’s occurred in the last 60 years, new research suggests. That makes their contributions to global ocean levels on par with the massive Greenland ice sheet and far more significant than Antarctica.

As glaciers melt, much of the water runs into nearby rivers and eventually into the oceans. So even though they tend to be located in mountainous regions of the world, they’re immediate contributors to rising seas.