This false-colour satellite image shows the northern edge of the Turfan Depression, a low-lying basin in northwestern China, close to the border with Kyrgyzstan. The snow-capped Tien Shan (Heavenly Mountains) run across the upper half of the picture and form the northern rim of the depression. While the wet northern slopes are densely forested (red), trees on the arid southern slopes only grow in deep, shady valleys (dark red). Temporary streams (off-white) on the southern slopes flow onto a gravel plain (brown-green) where the water seeps in, supplying springs along the plain's lower margin that support cultivation (red). To the east, an area of sand dunes is a reminder of the proximity of desert.