---
source: https://iinventedlight.com/library/notes/ice-and-snow-water-cycle.md
title: "Ice, snow, and glaciers in the water cycle"
license: CC-BY-4.0
license_url: https://creativecommons.org/licenses/by/4.0/
source_license: "US government work, public domain; restated in our own words"
attribution: "Summary by iinventedlight (AI-assisted). Sources: USGS, Ice, Snow, and Glaciers and the Water Cycle, US government work, public domain; USGS, Glaciers and Icecaps, US government work, public domain."
author: "iinventedlight (synthesis of cited sources); text drafted with AI assistance"
date: 2026-11-04
status: published
checked_on: 2026-11-04
as_of: 2026-11-04
confidence: medium
untested: "No observation or experiment was done; only the fetched government pages were read."
category: coverage-gaps
topic_area: "earth science: water cycle"
tags: ['usgs', 'water-cycle', 'glaciers', 'ice']
sources:
  - id: S1
    title: "Ice, Snow, and Glaciers and the Water Cycle"
    publisher: USGS
    url: https://www.usgs.gov/special-topics/water-science-school/science/ice-snow-and-glaciers-and-water-cycle
    accessed: 2026-11-04
    license: "US government work, public domain"
  - id: S2
    title: "Glaciers and Icecaps"
    publisher: USGS
    url: https://www.usgs.gov/special-topics/water-science-school/science/glaciers-and-icecaps
    accessed: 2026-11-04
    license: "US government work, public domain"
---
# Ice, snow, and glaciers in the water cycle

**Answer:** Ice, snow, and glaciers are storage pools in the water cycle. The water stored in glaciers moves very slowly compared to water in rivers, but both are part of the water cycle. Almost 10 percent of the world's land mass is currently covered with glaciers and ice caps, mostly in places like Greenland and Antarctica.

## Water in storage

Much more water is "in storage" at any one time than is actually moving through the cycle on an annual basis. By storage, USGS means water that is locked up in its present state for a relatively long period of time, from many years up to many centuries.

## Greenland

Almost the whole island of Greenland is overlain by a huge sheet of ice, almost three miles deep in places. The Greenland ice sheet averages almost a mile in thickness and contains about 10 percent of the total ice mass on the globe.

## How glaciers form and move

- Glaciers begin life as snowflakes. When the snowfall in an area far exceeds the melting that occurs during summer, glaciers start to form.
- The weight of the accumulated snow buries and compresses the previously fallen snow into ice.
- The ice slowly moves downhill in response to gravity, grinding away at the underlying sediment.
- Glaciers can vary from the size of a football field to an ice patch a hundred miles (161 kilometers) long.

## Ice and weather

Large continental glaciers and sea ice influence the weather, too. As ice is so white, sunlight is reflected back out to the sky, which keeps the earth's surface cooler than it would be if these bodies of ice didn't exist.

## Claims
- id: C1
  claim: Large areas of ice help keep the earth cool.
  source: S1
  evidence: "These large areas of ice help to keep the earth cool."
- id: C2
  claim: Water stored as ice is part of the water cycle.
  source: S1
  evidence: "Water stored as ice is part of the water cycle"
- id: C3
  claim: Glaciers begin life as snowflakes.
  source: S2
  evidence: "Glaciers begin life as snowflakes."

## Sources
- [S1] Ice, Snow, and Glaciers and the Water Cycle. USGS. https://www.usgs.gov/special-topics/water-science-school/science/ice-snow-and-glaciers-and-water-cycle . License: US government work, public domain. Accessed 2026-11-04.
- [S2] Glaciers and Icecaps. USGS. https://www.usgs.gov/special-topics/water-science-school/science/glaciers-and-icecaps . License: US government work, public domain. Accessed 2026-11-04.

License: this note is CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Summary by iinventedlight (AI-assisted).