Reducing black carbon emissions is key to preserving glaciers and their life-supporting benefits, writes Pema Gyamtsho, head of the International Centre for Integrated Mountain Development (ICIMOD).
If you have ever visited a glacier you will know how otherworldly they are. There is a certain stillness when standing on an iceflow, and a quality of light like no other.
Tragically, the opportunity to experience the magic of these centuries-old landscapes may not exist in the future, and nor will the life-supporting benefits they bring to communities and societies worldwide.
The latest expert research has revealed that glaciers are disappearing at an alarming rate. Since the turn of the century, they have lost more than 6,500 billion tonnes – or 5 per cent – of their ice. And the pace of melting is increasing. As much as half of the world’s glaciers could disappear by the end of the century if we don’t dramatically reduce carbon emissions.
The implications of this are deeply serious. Hundreds of millions of people worldwide rely to some extent on seasonal meltwater from glaciers, which act like giant reservoirs to help buffer populations from drought. And there are wider consequences too: glacier melt contributes to sea level rise which can devastate coastal communities and force relocation.
For the Hindu Kush region, where I am from, the threat to glaciers is particularly concerning. The Hindu Kush Himalayan mountain range stretches for 3,500km across eight countries in Asia. The mountain ecosystem is vital for the food, water and power security of up to two billion people and a habitat for countless irreplaceable species.
The Hindu Kush region is also, perhaps surprisingly, one of the most polluted in the world, with the majority of its citizens regularly breathing air that exceeds safe limits. As well as affecting animal and human health, and damaging economies and livelihoods, air pollution impacts water security by accelerating the loss of snow and ice in the mountains and affecting monsoon patterns and rainfall distribution.
A particular component of air pollution is black carbon – otherwise known as soot. A short-lived so-called “super pollutant”, black carbon only remains in the atmosphere for a few days, but has an immediate warming effect, up to 1,500 times stronger than carbon dioxide.
As a component of fine particulate matter, black carbon contributes to ill health and the more than 8 million premature deaths caused by air pollution annually. It is also a key driver of the economic costs of air pollution, which are estimated to be equivalent to over 6 per cent of global GDP each year. Black carbon and other super pollutants such as methane are responsible for half of the global warming witnessed to date.
Sources of black carbon include petrol- and diesel-fuelled vehicles, wildfires, household activities such as cooking or heating with wood or coal, and industrial activity. Black carbon emissions are also a major reason the Arctic is warming four times faster than other parts of the world, and why we are losing our glaciers. In one study conducted on a glacier in the Central Himalayas, black carbon contributed to 39 per cent of total mass loss observed during the pre-monsoon.
Overcoming obstacles
Scientists have long known about the impacts of black carbon but not enough has been done to address it.
A new report from the Clean Air Fund identifies six key types of obstacles to action – political, scientific, financial, regulatory, industrial and communication. It proposes technical and economically feasible solutions that could deliver an 80 per cent reduction in black carbon by 2030, from 2010 levels, compared to a 3 per cent reduction on a “business as usual” trajectory.
It seems to me that given the human health and environmental impacts of black carbon, including the accelerating threat it poses to mountains and glaciers, we would be mad not to act to overcome these obstacles and realise the potential reductions.
Indeed, as the Clean Air Fund report makes clear, reducing black carbon, alongside other super pollutants, would be the fastest, most effective way to slow climate change, while unlocking huge health and economic benefits.
Our experience in the Hindu Kush Himalaya region shows that investing in cleaner technologies, advanced monitoring, and strong policy support mechanisms will be critical for success in this mission.
Residential solid fuel burning and brick kilns together account for up to two thirds of the anthropogenic black carbon deposition in the region. Given this, a transition to clean energy is needed in all three residential sectors -cooking, lighting, and heating – which will also generate significant benefits for air quality and improved health outcomes in the region.
Other actions that would help reduce the black carbon emissions include requiring ships operating in or near the Arctic to use cleaner fuels, setting a new post-2025 black carbon emissions target at the Arctic Council, and prioritising black carbon in clean air and energy policies.
Countries can demonstrate leadership ahead of the next UN climate summit, COP30, by setting black carbon reduction targets in their updated Nationally Determined Contributions (climate plans).
Funding more research to deepen the evidence base for the impact of black carbon on both climate and health, with a focus on vulnerable groups, would also provide further impetus for action.
The United Nations General Assembly has designated 2025 as the International Year of Glaciers’ Preservation. We should take this opportunity to accelerate action to protect high mountain areas, including by reducing black carbon emissions, before it’s too late.
Pema Gyamtsho is the director general of ICIMOD and a former minister of agriculture and forests in Bhutan.
This piece was produced by SciDev.Net’s Asia & Pacific desk.