First off, to understand how glaciers have an impact on the hydrosphere you need to know what a glacier is. Glaciers, (also known as Icebergs when they break off of the main glacier and float on water) are a body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds, it grows over many years, often centuries. Although some of these parts of glaciers may float on salt water or the ocean they are made up of fresh water. Now, to truly understand glaciers lets go back to the beginning of a glacier. Moist warm air rises up from the ocean and then cools, condenses and falls down onto the ground as rain or snow. You need lots of snow to create a glacier, more than a mountain