The 1986 image shows the region prior to a major retreat of the glaciers. The 2002 image shows a retreat of nearly 10 km (5.5 miles) of the glacier on the left of the scene. The smaller glacier on the right has receded over 2 km (1.3 miles.) In front of the smaller glacier two ribbon lakes have formed behind the debris left behind from the glacier's advance. Scientists and Peruvian government managers will use the Landsat imagery to monitor the rate of retreat of the glaciers and the impact on water bodies caused by the changes in size and direction of the glaciers.