The Tibetan Plateau is situated in one of Earth's extreme continental climate settings and is influenced by numerous climatic regimes such as the East Asian and Indian monsoons and westerlies. It is the largest region of the world where permafrost is present at mid-latitudes and its relative warmth and shallow thickness makes it more sensitive to climatic warming than the arctic region. Changes in permafrost temperature, extent and active layer thickness have been observed for decades. In this paper we review these changes in this dynamic permafrost region, especially noting the changes in permafrost distribution and area loss of about 99,000 km(2) per decade, increases in active layer thickness of 4-8 cm/year, and increases in thawing days of about 10-16 days/decade. As soil temperature and soil water content have changed, river run-off has decreased over most of the year. Warmer temperatures may have transformed the Tibetan Plateau from a net carbon source in the 20th century to a net sink as the increase rate of net primary production is faster than that of soil respiration.