The Mogao Grottoes, a UNESCO World Heritage site in Northwest China, are using smart doors to combat climate challenges. When carbon dioxide levels rise inside the caves, gray doors automatically open for ventilation, protecting millennia-old murals.

Built in 366, the site features 492 art caves among 735 total, renowned as the world's largest and richest Buddhist art repository.

Climate change has intensified extreme weather incidents, threatening the murals and sculptures. The smart doors, co-developed by the Dunhuang Academy, seal out sandstorms, block moisture during heavy rain, and provide ventilation on sunny days to optimize internal air conditions. They have been installed in multiple caves at Mogao and the Western Thousand Buddha Caves.

Though Dunhuang's arid climate has preserved the grottoes for centuries, data show a warming-wetting trend in Northwest China since 2000, with rainfall increasing eightfold compared to the period from 1961 to 2000.

A monitoring system with over 600 sensors tracks real-time temperature, humidity, CO2, visitor flow, and regional weather. Humidity is critical for mural preservation, and a red-yellow-green alert system supports protection decisions. During extreme weather, ticketing may be suspended and cave doors closed to prevent moisture damage.

Researchers are also using multi-field coupling labs to simulate weather conditions from minus 30 C to 60 C, accelerating aging tests to develop preventive measures. Sand-control barriers have reduced annual sand accumulation from 3,000 to under 200 cubic meters, while flood-control projects have mitigated water risks.

This integrated "Dunhuang solution" now covers six grotto sites under the academy's management and is being shared with heritage sites along the ancient Silk Road through training programs for people from Central Asia.