Technological Innovations Safeguard and Digitally Preserve China’s Millennia-Old Mogao Grottoes

Millennia-Old Mogao Grottoes

Dunhuang, The Gulf Observer: As the Chinese Lunar New Year marks the beginning of festivities, the Mogao Grottoes, a UNESCO World Heritage Site in Dunhuang, Gansu Province, has attracted a steady flow of tourists. Dating back to the 4th century, the millennium-old cave temple complex, featuring 735 caves carved into a cliff, boasts over 60,000 cultural relics and 45,000 square meters of murals.

Situated in a vast desert, the Mogao Grottoes faced severe threats from wind and sand nearly a century ago. To combat these challenges, Chinese researchers have employed scientific and technological methods to ensure the grottoes’ preservation.

Initially, manual efforts involved cleaning 3,000 to 4,000 cubic meters of sand annually to prevent pollution and erosion of the murals and colored sculptures. In the late 1980s, scientific techniques were introduced, including the installation of automatic weather stations atop the caves to monitor wind conditions and the construction of grass grid sand barriers and nylon net fences covering extensive areas.

A 2011 project, with an investment of nearly 14 million yuan, significantly reduced the annual inflow of sand into the caves by 85 percent, according to monitoring data. Over 600 sensors have been installed to monitor temperature, humidity, carbon dioxide concentration, and passenger flow for disaster prevention.

While achieving successful outcomes in safeguarding the Mogao Grottoes, experts at the Dunhuang Academy have also undertaken initiatives for digital preservation. Since the late 1980s, they began photographing the murals and digitally piecing together comprehensive representations using computers.

Challenges in maneuvering within the narrow grottoes led to a 20-year digitalization process, capturing thousands of photos for each mural covering around 10 square meters. With the advent of 3D laser scanning technology in recent years, data acquisition efficiency has significantly improved, allowing experts to capture images of 20 to 30 caves annually.

By the end of 2022, the Dunhuang Academy completed the digital photography collection of 289 caves, along with the 3D reconstruction of 45 colored sculptures and 140 caves. These digital archives, totaling over 6,500 high-definition images, are accessible worldwide through an official blockchain-based platform launched in 2022.

Yu Tianxiu, director of the Dunhuang Academy’s cultural relic digitalization institute, highlighted the transformative impact of technology, stating, “Today, scholars and culture enthusiasts across the globe can access these images from their homes with just a click of the mouse, compared to the past when cultural relics workers had to use ladders and rely on flashlights or telescopes to observe the murals.” The technological advancements ensure the permanent preservation and global accessibility of the invaluable Mogao Grottoes.