Tibet’s “lake region” is lightly populated by nomadic tribes, and stretches from the west of the occupied Chinese region eastward to the sources of some of Asia’s greatest waterways.

Visible in the image to the right are some of the many small lakes, mainly salt or alkaline, which appear in contrast to the tundra-like frozen bogs that are covered with tussocks of grass during the summer months.

Since there are generally no outlets for the lakes, mineral deposits consisting of soda, potash, borax and common salt accumulate in their waters. The largest lake visible in the upper right of the image is Siling Co, which is listed as a saltwater lake.

Temperatures in the thin, dry air of the Tibetan Plateau section seen in the image ranged from around 20 degrees Fahrenheit in the morning to warmer than 40 degrees a few hours after the image was taken.

Some of the lakes appear to be relatively free of ice, while others are clearly frozen solid at elevations that average around 12,500 feet.

The lake region is quite literally an arid and wind-swept desert, lying in the “rain shadow” of the Himalayas. The towering mountain range acts as a barrier to moisture and monsoon rainfall from the Indian Ocean to the south.

Not visible in the image are some of the region’s geothermal springs. Columns of ice sometimes develop around them as nearly boiling water freezes solid while being ejected by geysers into the often bitterly cold Tibetan air of winter.

Image: European Space Agency