Reducing black carbon in the region will have multiple benefits and save lives


The Himalaya region is among the most vulnerable parts of the world to climate change. Retreating glaciers reduce dry-season water availability and increase the risk of glacial lake outburst floods, while increased climate variability and changes in rainfall and monsoon patterns could threaten regional water and food security as well as change the occurrence of landslides and floods.   Changing temperatures and moisture availability also threaten rare or endangered species and ecosystems.

Part of the climate change experienced in the Himalayan region is a result of the greenhouse gas carbon dioxide (CO2), which can remain in the atmosphere and impact the climate for centuries. However, it is also caused by ‘short lived climate pollutants’ or SLCPs.  SLCPs are air pollutants that remain in the atmosphere for only a short time, but still have an impact on the climate.  In recent decades the Himalayan region has experienced increasing urban and rural air pollution, affecting people’s health, agriculture, visibility and tourism.  Globally, air pollutants have been shown to cause as many as seven million premature deaths every year, destroy millions of tons of crops, and push up earth’s temperature, contributing to climate change.  

Photo credit: Dr Arnico Panday/ICIMOD

The short atmospheric life time of SLCPs has two important consequences for policy makers: First, it means that actions to reduce their emissions yield results much faster than actions to reduce CO2 emissions.  Second, it means that they are most concentrated near their source regions. Because they also have significant impacts on health and agriculture, actions to reduce their emissions bring significant non-climate benefits near their source regions. Many of the biggest sources of SLCPs can be addressed using well-established measures that are cost-effective to implement.

Three years ago, the Climate and Clean Air Coalition (CCAC) was set up to reduce SLCPs globally. The growing coalition now has 100 members representing countries, international organizations, NGOs, and private industry and is focused on finding practical solutions to reduce four key short-lived climate pollutants: black carbon, tropospheric ozone, methane, and hydrofluorocarbons (HFCs).   

What are short-lived climate pollutants?

Black Carbon: a tiny black particle emitted during the incomplete combustion of fossil fuels and biomass, for example from brick kilns, open fires, diesel engines, and traditional cookstoves. Black carbon particles contaminate the air and darken snow and ice surfaces, making them less reflective and more light absorbent, which causes local warming and increases the melting rate of snow and ice. Black carbon has been recognized by the World Health Organization (WHO) as a carcinogen.

Tropospheric Ozone: a secondary gas because it is not directly emitted, but rather formed by sunlight-driven oxidation of ’precursor gases’, such as volatile organic compounds and nitrogen oxides. In the upper atmosphere (stratosphere), ozone acts as a shield, protecting the earth from harmful ultraviolet radiation. But in the lower atmosphere (troposphere) ozone warms the air and attacks lungs and leaves.

Methane: a powerful greenhouse gas with an atmospheric lifetime of approximately 12 years. Methane directly influences the climate system but also has indirect impacts on human health and ecosystems through its contribution to the formation of tropospheric ozone.

Hydrofluorocarbons (HFCs): powerful factory-made greenhouse gases used primarily in air conditioning, refrigeration, foam-blowing, fire suppression, solvents, and aerosols. Although they currently represent only a small fraction of the total greenhouse gases (less than 1%), HFCs are among the fastest-growing ones (in percentage) in many countries.

In the Himalayan region, action on just one of these SLCPs, black carbon (or ’soot’), could have multiple benefits for health, food and water security, and the environment. Household cookstoves are one of the main sources of black carbon in the Himalayan region. Typical cookstoves burn biomass (wood, dung and crop residues) for domestic energy, and usually have very incomplete combustion, which produces choking air pollution. They pollute both outdoor and indoor air, the latter of which is particularly dangerous for women and children who are most exposed. 

Reducing exposure to black carbon pollution from cookstoves could cut premature deaths in the region   by as much as three-quarters of a million people. Broaden the focus to diesel engines, brick production, and other pollution sources and the number goes even higher. The effect on agriculture could be just as dramatic: more than 15 million metric tons   of staple crops could be added to the region‘s food supply with the reduction of black carbon and methane.

Poor health isn’t the only regional problem exacerbated by black carbon. The glaciers and permafrost of the Himalayas, together with the Tibetan Plateau, the Hindu Kush and the Karakoram region, store more freshwater in the form of ice and snow than any region outside the Arctic and Antarctic: nearly 10% of the global total. Black carbon particles darken snow and ice surfaces, causing them to absorb more light and heat and melt faster. The melting of these huge stores of water and changing precipitation patterns threaten the water resources of up to 1.3 billion people living downstream of the Himalayas. This in turn has regional and global consequences for food security as the river basins fed by this water is responsible for the production of nearly 25% of the world’s cereals.

In the Himalayan region broadly, a number of efforts by the Climate and Clean Air Coalition (CCAC) are already underway:

  • Reducing Black Carbon Emissions from Heavy Duty Diesel Vehicles and Engines

Under the Diesel Initiative, which aims to catalyse major reductions in black carbon through adoption of clean fuel and vehicle regulations and policies, CCAC has supported country projects in Bangladesh, which led to the government’s signing of a project to introduce low sulphur fuels. Under the Initiative’s Green Freight Action Plan, Bangladesh is being supported by CCAC in its design and establishment of national green freight programmes. In addition, CCAC has approved a project to develop black carbon emissions reduction strategies for the country’s largest port, the Port of Chittagong, among other ports worldwide.

  • Mitigating Black Carbon and Other Pollutants From Brick Production

One thousand five-hundred billion bricks are produced every year, with the biggest brick producers located in Asia, including China, India, Pakistan, Vietnam, Bangladesh and Nepal. Recent studies show that implementing more efficient technologies, mainly during the firing of bricks, can result in the reduction of pollutant emissions from 10 to 50% depending on the process, scale, and fuel used. The CCAC Bricks Initiative is trying to elevate the anti-pollution issue onto national governments’ agendas, including through a Brick Kilns Policy Advocacy Network (PAN) at the global level and regional networks in South Asia and Latin America.

The CCAC’s Asian network, PAN Asia, is being coordinated by the International Centre for Integrated Mountain Development (ICIMOD) and will support Bangladesh, Nepal, India, and Pakistan in the development of comprehensive national strategies for cleaner brick production. The strategies will take into account the unique social, political, market, and resource conditions in each country. The Expert Group, formed from the Global PAN Workshop, will interact with the regional PAN for Asia and PAN for Latin America, and the experts will review national strategies and guidelines for implementation.

  • Addressing SLCPs from Agriculture 

The International Cryosphere Climate Initiative (ICCI) and other partners are leading the open burning component of the CCAC Agriculture Initiative in assessing options to reduce open burning in the Eastern Himalayas as well as the Andes region in 2014-2015, two cryosphere regions particularly sensitive to black carbon emissions. The ICCI and ICIMOD will hold a conference on the mitigation of open agricultural burning in the wider Himalayan region in Kathmandu, Nepal, on 20 and 21 February 2015.

Upon completion of the initial phase of work, these efforts will help identify ways to reduce black carbon emissions from open agricultural burning practices. Future projects will be designed in order to catalyse reductions in the estimated 40% of black carbon emissions globally arising from this source, and for which a 50% global reduction could result in 190,000 avoided deaths annually on a global scale.

  • Promoting HFC Alternative Technology and Standards

The CCAC has approved a variety of projects for Asian countries under the HFC Initiative. The CCAC is supporting the conduct of inventories of national consumption of alternatives to HFCs in 14 developing countries, among them Bangladesh, Cambodia, Indonesia, Jordan, Maldives, Mongolia, and Vietnam. With technical and financial assistance from the CCAC, a technology demonstration project is being conducted on the capital island of Maldives, and could extend to other population centres, such as tourist resorts. This study is expected to inspire other small island developing states and low-volume consuming countries. For India, CCAC has approved a technology demonstration project to demonstrate the commercial and technical viability of alternatives to HFCs in vehicle air-conditioning systems designed for high energy efficiency under high ambient temperature conditions.

From February 22-27 the Coalition’s Working Group, its main governing body, will be meeting in Kathmandu to discuss the work of the Coalition around the world as well as in the region. For more information, contact the Coalition’s secretariat at

Source: Time to act/CCAC

Dr Arnico Panday
Senior Atmospheric Scientist and Programme Coordinator, ICIMOD


Ms Helena Malin Valdes
Head of the CCAC Secretariat