English: This image shows two graphs of changes in glacial and
ice cap mass balance (the amount of snow and ice contained in a
glacier or ice cap) for large regions (
Europe, the
Andes, the
Arctic,
Asian high mountains, North West
USA and South West
Canada,
Alaska and coast mountains, and
Patagonia). Graph (a) shows cumulative mean specific mass balances and graph balances of glaciers and ice caps, and (b) cumulative total mass balances of glaciers and ice caps. Mean specific mass balance shows the strength of
climate change in the respective region. Total mass balance is the contribution from each region to
sea level rise.
(a) plots time (1960 to ~2005) against cumulative mean specific mass balance, with most regions showing a decline in mass balance over time. (b) plots time (1960 to ~2005) against cumulative total mass balance, with most regions showing a decline in mass balance over time (see also
retreat of glaciers since 1850). From the cited public-domain source (NOAA, 2010): "Indirect indicators of warming such as borehole temperatures, snow cover, and glacier recession data, are in substantial agreement with the more direct indicators of recent warmth. Evidence such as changes in glacial mass balance (the amount of snow and ice contained in a glacier) is useful since it not only provides qualitative support for existing meteorological data, but glaciers often exist in places too remote to support meteorological stations. The records of glacial advance and retreat often extend back further than weather station records, and glaciers are usually at much higher altitudes than weather stations, allowing scientists more insight into temperature changes higher in the atmosphere."
Further discussion of this topic can be found in the following source, which also refers to these two graphs: Lemke, P., J.,
et al. 2007: figure 4.15, in
4.5.2 Large and Global-Scale Analyses, in:
Chapter 4: Observations: Changes in Snow, Ice and Frozen Ground. In:
Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (Solomon, S.,
et al., (eds.)). Cambridge University Press. Also available as a PDF
(figure is shown on p.359).