Ancient adobe structures in Peru have come under threat due to El Nino-triggered rains, which could severely damage archeological sites that the country has strived to preserve.
Chan Chan, the ancient city in the Moche Valley outside Trujillo was once a thriving capital of the Chimor Empire, built to make use of the valley's precious water resources and irrigation systems over a thousand years ago.
Located on the northern coast of present-day Peru, about 480 km north of Lima, the ancient city is one of the largest and most important pre-Hispanic earthen architecture cities in the Americas. In 1986, it was inscribed on the World Heritage List for its extensive, hierarchically planned remains, which include remnants of the industrial, agricultural, and water management systems that sustained it.
Today, however, the clay architecture built centuries ago is vulnerable to flooding, soil erosion, and moisture damage.
"As the buildings are made of earth, rainwater erodes the surface of the walls and then seeps into the interior, creating grooves and voids through water-flow erosion. In the most severe cases, it may even affect the core structure of the walls, leading the wall or the whole structure to collapse," said Henry Gayoso Rullier, head of the Research, Conservation and Enhancement Unit of the Chan Chan Archaeological Complex Special Project.
To prevent rain erosion, archaeological conservators have installed roofs with drainage systems in key areas of the ancient city. Staff regularly repair the wall surfaces with chemical curing agents and mud.
"Depending on the specific area and conditions, we install roofs with drainage systems over certain sections to prevent rainwater from falling directly onto the walls, particularly those with decorative elements. For undecorated walls, we apply a protective layer to the top and then cover the sides and surfaces with a sacrificial layer, namely a thick coating of adobe and mud, to encase the entire structure. This ensures that when it rains, the water erodes this protective layer first, sparing the original wall from direct damage," said Rullier.
El Nino-triggered weather threatens preservation of Peru's world heritage site Chan Chan
After more than three months at sea, members of China's 16th Arctic Ocean expedition have jointly created a painting that captures both the triumphs and trials of polar scientific research.
Organized by the Ministry of Natural Resources, the expedition deployed four ships, Xuelong, Xuelong 2, Jidi, and Tansuo 3, to study extreme environmental changes in the Arctic against the backdrop of accelerating global warming. On September 29, Xuelong and Xuelong 2 returned to Shanghai after completing their missions.
During the voyage, China Media Group (CMG) reporters aboard Xuelong invited nearly 100 crew members to collaborate on a canvas, sharing their experiences. The painting depicts the difficulties and challenges they faced, the honors and expectations of their research, and the images of those dedicated to science.
Before any crew member ever picked up a brush, the Arctic had already sketched the background with its extreme weather. Strong winds, torrents, and a harsh environment posed major challenges for the researchers.
"After staying outside for some five or ten minutes, our hands would already be frozen red. When we reached the trough of the waves [on a boat], it would look as if the waves were coming right over our heads," recalled Zhu Chengwei, an expedition member.
Despite the hardship, the researchers successfully tested and used domestically produced advanced ocean observation equipment in polar research -- one of their proudest moments, which they recorded on the canvas.
Qin Chuan, captain of the Xuelong ocean team, chose to paint a domestically produced monitor float.
"This is an Argo float we deployed, which automatically monitors ocean profiles. It has great significance for understanding the basic marine environment, and it's made in China," he said.
Xie Haixiang, director of the Xuelong laboratory, sketched a fundamental research equipment for the trip.
"I will draw a CTD (Conductivity, Temperature, and Depth instrument). The CTD is the most important equipment for ocean surveys, providing the most basic data and water samples," he said.
"Only by carrying equipment onto the Arctic sea ice yourself and lowering the instruments, can you get what you want. For instance, we take a little ocean water, and analyze what's in it, to understand the changes each year. Global warming needs to be understood through different dimensions," recalled researcher Zhu.
Beyond the canvas, what stands out even more striking are the moments of dedication: veteran members leading newcomers onto the ice, a group holding its ground in level-8 gales and heavy snow, and 30 people relaying to recover equipment stuck in the ice.
The most important element, beyond any record or image in the painting, is this group of expedition members who fear no hardship.
"Whenever I think of the polar spirit, countless images of those standing at the very front would flash before my eyes," Zhu said.
"What we have done today will benefit future generations. Although we are doing something that may seem very insignificant, I believe it will surely prove its worth in the future,"said Ning Wenfeng, another team member.
China's 16th Arctic expedition crews paint portrait of proud polar expedition moments, hardships
