The Athabasca Glacier in Western Canada is melting faster than new snow is added. Its snout is receding about 15 metres each year. The glacier’s surface is also melting downwards - several metres each summer.
Variations in climate cause glaciers to advance and retreat. The current warming trend has caused the Athabasca glacier to retreat about 1.5km in the last 100 years.
Glaciers are good indicators of climate change because they average out short term meteorological variation.
The flat rock surface in the foreground is marked by parallel scratches. These were made by rocks which were embedded in the base of the glacier ice as it flowed over this point.
This picture was taken in 2005. The date marker shows where the snout of the glacer was in 1992. At this rate, this mid latitude valley glacier will be gone by the end of the current century.