By Isabelle Wicks What is firn? Firn is a material that is halfway between snow and glacier ice. It is defined as snow that has remained on a glacier for at least one year without being melted during the summer. It is not completely solid like ice, but it is also not light and fluffy […]
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By Dr Tom Slater, University of Leeds, UK How does mass balance vary over Greenland? The mass balance of the Greenland Ice Sheet is the net difference between ice gains through snowfall, and ice losses through melting at its surface or underneath its floating ice tongues, and through the calving of icebergs from glaciers flowing
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More videos available here: Films and Video Resources Watch this brief introductory video, made by Time for Geography with Bethan Davies and Simon Cook, about glacier mass balance. This is suitable for GCSE and A-level students. This more in-depth lecture (29 minutes) introduces the concept of glacier mass balance, and then goes on to discuss
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Snow How do we build a glacier? We start with a snowflake. Snow, over time, is compressed into firn, and then into glacier ice. Snow falls in cold regions, such as mountain tops or in polar regions. In glaciology, snow refers to material that has not changed since it fell1. Snow is very light and
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This page highlights some of the excellent teaching resources available for exploring glacier mass balance. For more ideas, see the Resources for Teachers page. Case study: USGS Benchmark Glaciers The USGS has an excellent resource on the mass balance of Lemon Creek Glacier, a World Reference Glacier, and the other USGS Benchmark Glaciers. This has
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What is glacier mass balance? The Mass balance of a glacier can be thought of as the health of a glacier. Mass balance is the total sum of all the accumulation (snow, ice, freezing rain) and melt or ice loss (from calving icebergs, melting, sublimation) across the entire glacier. If glaciers have a mass balance
This page draws from the excellent review of glacier melt by Hock (2005) and the equally informative chapter on ‘Snow, Ice and Climate’ (Chapter 2) in Glaciers and Glaciation by Benn and Evans (2010). I highly recommend these resources if you want to dive deeper into the processes of glacier melting and the surface energy
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Rock and sediment debris often cover part or all of a glacier’s surface, where it plays an important role in surface energy balance and the rate of glacier ablation. The relationship between debris thickness and glacier melting Measurements taken at the surface of glaciers show there to be a strong relationship between the thickness of
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How much land ice is there in the World? Most (99.5%) of the permanent ice volume in the world is locked up in ice sheets and glaciers. The Antarctic Ice Sheet is the largest store of frozen freshwater; it would raise sea levels by 57.9 m (its “sea level equivalent”, or SLE) on full melting
What is the global volume of land ice and how is it changing? Read More »
Glacier accumulation | Glacier ablation | Equilibrium line altitude | Glaciers as a system | Further reading | References | Comments | Glacier accumulation A glacier is a pile of snow and ice. In cold regions (either towards the poles or at high altitudes), more snow falls (accumulates) than melts (ablates) in the summer season.
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