The accelerated melting of the Himalaya has often been blamed on the greenhouse effect caused by the historical emissions of carbon dioxide by rich countries. And this has been used as an excuse by developing countries to blame the west and do nothing to control their own emissions.
They can’t do that any longer. There is growing evidence that glacial retreat in the Himalaya is caused by tiny particles of wind-blown soot and dust generated in cities like Kathmandu and deposited on the mountains. Last month, scientists for the first time quantified the role that this ‘black carbon’ plays in melting the snow faster.
This winter, the pollution haze and smog trapped under an inversion layer in Kathmandu Valley was the worst ever. Added to this was the region-wide pall of dust and soot over the Indo-Gangetic plains, all of which was wafted by prevailing westerly winds into the mountains.
Tiny soot particles emitted from the exhaust of diesel vehicles, thermal power plants, firewood, and dung cooking stoves have long been known to cause lung disease, but a new study has shown that they also have a profound role in heating the earth’s surface.
The most comprehensive study of black carbon yet conducted was published in the Journal of Geophysical Research: Atmospheres in January and concludes that the heat-trapping property of black carbon was double of previous estimates and combined with other effects was three times worse for the climate as had been thought until now.
“Finally the study has cleared the doubts of many who for years played down the role of pollutants such as black carbon in global warming,” says Mark Lawrence, director of the Germany-based Institute for Advanced Sustainable Studies. Lawrence was in Kathmandu with his team of experts to oversee the Sustainable Atmosphere for the Kathmandu Valley project which has begun measuring the valley’s air pollutants, including black carbon.
However, a NASA project to fly over the Himalaya to do a ‘curtain study’ of air samples last year had to be cancelled because of Thailand’s refusal to grant stopover rights for its research aircraft at Utapao Air Base. The study would have mapped black carbon suspended in the atmosphere above the Himalaya and the Indian Ocean that are spewed out in China, India, and other countries in the region called the Asian Brown Cloud (ABC).
Soot particles are called ‘short-lived climate pollutants’ in scientific jargon, and the United Nations Environment Programme (UNEP) is taking the lead in getting governments in the region to clean up their air. Ministers from 19 Asian countries, including Nepal’s Minister for Science, Technology, and Environment Keshab Man Shakya, got together for a meeting organised by UNEP’s Climate and Clean Air Coalition(CCAC).
Gokarna Mani Duwadi, joint secretary at the Ministry of Science, Technology, and Environment who attended the meet said participants agreed to share technology and data on black carbon and other greenhouse gases. “Nepal’s failure to implement the ban on old vehicles to control emission was also discussed,” Duwadi told us.
Arnico Panday, lead atmospheric scientist at the Kathmandu-based International Centre for Integrated Mountain Development (ICIMOD), is conducting a study of the impact of air pollutants including black carbon in the Jomsom area. Unlike carbon dioxide gas that remains in the atmosphere for centuries, solid soot particles stay suspended only for a few weeks before settling or being washed down by rain.
“The Journal of Geophysical Research study has provided a better understanding of how black carbon affects the climate by quantifying its effect,” Panday explains.
While reducing carbon dioxide emission is a long-term global challenge, controlling pollution can be carried out locally and faster. For example, the promotion of improved cooking stoves in rural Nepal has not just reduced respiratory diseases caused by indoor pollution, but also decreased the amount of soot in the atmosphere. Other measures Nepal can take immediately are to have stricter controls on vehicular emissions, cleaner brick kilns, and controlling wind-blown dust which are directly upwind from Himalayan glaciers.
“Reducing soot and dust from the atmosphere is easier and gives us some more time to address the larger global issue of carbon dioxide emissions,” says Maheswar Rupakheti of the Institute for Advanced Sustainable Studies. “We have to control pollution in our own backyard if we are to save our mountains from melting, instead of just blaming industrialised nations for their greenhouse gas emissions.”
Lost in the smog
Dirty snow is melting our mountains faster
An automobile company partnering with a scientific research centre to improve air quality? Yes, that is exactly what the Czech car-maker Skoda is doing with the Kathmandu-based International Centre for Integrated Mountain Development (ICIMOD) to raise awareness among the public about the impact of black carbon and its negative health and environmental impacts. The one year partnership will complement ICIMOD’s own research, and help install improved cooking stoves in 300 rural homes in Makwanpur district south-west of Kathmandu. The improved stoves are more fuel-efficient and smokeless, reducing lung infections inside homes and reducing the emission of soot particles into the atmosphere. The Patan Academy of Health Sciences is also involved and is conducting a health impact study in the homes where the stoves are installed.
“This is a small start, but we must all do our bit to clean up the air and protect our mountains,” says Skoda’s Vishnu Kumar Agarwal (pictured above left with ICIMOD’s David Muldoon), “we cannot endanger the environment and community for growth.”