These close-ups of one of the larger lakes show how the formation and reduction of the lakes affected sand dunes.

• Sand dunes became inundated as the lakes formed. In the 2001 image, many larger dunes were small islands in the lake.
• Bright sand dunes re-emerged as the lake level dropped. In the 2013 and 2017 images, a few dunes are still islands.
• The darker ground in the later images indicates former water levels—the darker tone means moistened ground.