There was a time an event would not begin without a photographer.“I remember the days when event organizers would even delay a show if the photographer was running late,” says Balachandra Raju,a photographer of Sathyam studio,a still surviving photo studio in India’s southern city of Chennai.

Photo studios are facing extinction in the digital age.But as they struggle to continue doing the business,one research project is looking at ways to preserve their legacy(遗产) by digitizing archival(档案的) pictures.

The project,funded by the British Library,visited around 100 photo studios across the south Indian state of Tamil Nadu and digitized 10,000 prints.Many of the photos were taken between 1880-1980,and they ranged from pictures of families and famous stars to weddings and funerals.“The digital archive will be useful for those interested in history,” Said Zoe E Headley,one of the researchers.Ramesh Kumar,another researcher on the project,called it a “gold mine” for photographers.“The research we’ve done also highlights production techniques used before digital photography arrived in our cities and towns,” he said.

However, the researchers would often find old photos piled on top of one another in the storage room of a studio.“No one had bothered to clean them,” Kumar said,adding that many photos had been damaged due to the hot and wet weather in Tamil Nadu.

The owner of Nallapillai studio in central Tamil Nadu said he spends about 20,000 rupees (￡230;$310) each month to run the studio that was founded by his great grandfather almost 150 years ago.To survive in this digital age has been a struggle.“Many customers don’t book us for special events anymore,” he said,adding that they had all got smartphones to do the job.“I’m not sure if photo studios will exist five years from now,” he said.But this is why,according to Mr Raju,this archival project is so important.

In September, when UNESCO Director-General Audrey Azoulay visited Zhoukoudian in suburban Beijing, which is famous for the discovery of Peking Man living between 700,000 to 200,000 years ago, she was full of praise for the structure that successfully protected Yuanrendong Cave from an unusual rainstorm in July.

The cave in the central area of the site has so far revealed the remains of 40 individuals. The structure protects the site from the weather, including heavy wind, snow and hail, and its design fits in with the surrounding environment, Qin Changwei, secretary-general of the Chinese National Commission for UNESCO, said at the 2nd World Cultural and Natural Heritage Forum in Beijing on Nov. 17 and 18. “It provides a reference for the protection of precious cultural relics, and suggests measures for helping heritage sites respond to the influence of climate change.”

Organized by the World Heritage Institute of Training and Research for the Asia and the Pacific Region under the Auspices of UNESCO(Beijing), and the China Foundation for Cultural Heritage Conservation among others, the forum brought together some 50 professionals to discuss the protection and sustainable (可持续发展的) development of heritage sites. Scholars stressed the influence of climate change on heritage sites, and offered suggestions for how to solve the problem.

“Entering the 21st century, climate change has been the subject of in-depth discussion by the UNESCO World Heritage Committee. Questions like how to balance between humans and nature, how to respond to natural disasters caused by climate change, and what new challenges this brings to World Heritage Sites, are worth consideration,” says Qin. “Solving the problem requires us to unify, making full use of advanced technology, such as space and digital technologies, and jointly developing risk prevention and response plans,” he adds.

Even for a civilization as advanced as the Harappan, a second drought was perhaps one too many. The climate disaster may be what drove the ancient society to disappear step by.

The Harappan started in the Indus valley around 5200 years ago, strongest around 2600 BC. Much about them is unknown. Yet archaeological remains tell the story of the people, skilled in trade and city planning, and particularly good at controlling water. Their huge cities, complete with excellent systems for underground water and public baths, existed long before the Roman Empire.

But by 1900 BC, their society seemed to be on the fall, and by 1300 BC, the Harappan civilizations had broken down. Several ideas have been put forward to explain the downfall, including invasion and climate change. One recent study refers to a major drought in the northern half around 4200 years ago. This event was recently considered as the start of the Meghalayan period. It is thought to have broken up climate systems around the world, including the summer monsoon rainfall the Harappan depended on.

Nick Scroxton at University College Dublin, Ireland, and his team are now challenging this idea after studying 10 ancient records. They found some facts of a sudden drought starting around 4260 years ago. The study suggests the Harappan faced a sharp decrease in winter rain. “The civilization suffered, that's for sure,” says Scroxton. But that wasn't the end of the Harappan. “Their politics might change, the crops might change, the location of their cities changes, but they adapt,” says Scroxton.

Some 300 years later, however, just as the winter rains were starting to recover, a hottest drought kicked off. This was a slowing reduction in the sum monsoon rains over several centuries. Scroxton and his team say this second drought changed the Harappan into a poor society that disappeared at last.