Dagze Co (Lake) is one of many inland lakes in Tibet, with a present area of 260 km2 (100 square miles). In glacial times, the region was considerably wetter, and lakes were correspondingly much larger. Changes in climate have resulted in greater aridity on the Tibetan Plateau. The numerous concentric rings that circle the lake are fossil shorelines, and attest to the historical presence of a larger, deeper lake.
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Original entry was from the NASA Earth Observatory; [1]