There are about 160,000 glaciers in the world. Most of them have been around for hundreds of thousands of years but over the past few decades some have completely disappeared and most are losing ice at unprecedented rates. In some regions, glaciers act as naturally regulated water reservoirs that supply water for 2 billion humans. The loss or decline of glaciers in these regions will create severe hardships for these people.
Perhaps even more important, glaciers are the proverbial canary in the coal mine for world climate. They are extraordinarily sensitive to minute changes in precipitation and temperature, providing an accurate gauge of the rate of climate change and an indicator of how fast we need to respond and how drastic the measures we need to take.
The Glacier Monitoring Program (www.ptaagmb.com) was developed to monitor daily changes in the health of 200 glaciers around the world, providing a broad overview rather than the local or regional 'spot checks' on which other monitoring projects have focused. To date about 40 of the 200 glaciers, in thirteen different countries, are shown on the PTAAGMB site.