as construction and manufacturing, by using the latest plant designs in the poorest countries – and also to vastly improve efficiencies and recycling. Eventually, many dirty industries will become obsolete and be replaced by newer ones, providing an opportunity to design pollution avoidance from the outset.
The atmosphere of the Anthropocene is remarkable not because it is infused with a range of chemicals and particulates – natural events such as volcanic eruptions can produce that – nor because it is the first time humans have produced their own emissions, but because it is the first time that humans have done so on the global scale of the planet’s biggest natural events.
Our vast population – already more than 7 billion – is part of the cause. An increasing proportion of humanity relies on the goods, services and energy produced through dirty industrial activity. And on top of this, people are producing their own home-made pollution, the combined effect of which is turning the invisible air brown.
Kathmandu, Nepal’s only real city, is inscrutable through thick acrid smog. Pollution and dust generated in the bowl-shaped valley is not easily dissipated – there is limited rainfall to wash it away and little wind. The air is so laden with dirt that the shopfronts all wear a film of grime. Lacking customers, underemployed staff spend their hours pointlessly dusting and sweeping – shifting the miasma, which resettles in seconds. Visibility is so poor that flights are often cancelled or delayed, but perhaps not as often as they should be: there were five plane crashes here in 2012–13 alone, killing more than sixty people. Most of the haze, around two-thirds, comes from burning biomass for cooking, like the dung fires I saw in Nangi, with fossil fuels supplying the remainder. Plumes of smoke rise from the wood and dung fires burning in every household and merge with the emissions of factory chimneys and agricultural clearance fires. In the streets, motorbikes and cars with badly tuned engines crawl bumper to bumper, farting out sooty black puffs. The resultant fug hangs over the region for the entire season and well into the spring. It spreads in mile-long clouds of brown haze for thousands of kilometres from the Yellow Sea to the Arabian coast, and its sooty particulates have even been discovered in the Arctic ice at Svalbard.9 The brown cloud can be seen as a stain over Asia in satellite images, but it has become a highly emotive issue. When the pollution layer was at first called the Asian Brown Cloud, India complained, and so the United Nations Environment Programme renamed the haze ‘Atmospheric Brown Cloud’ during its follow-up study.
The warming effect of the brown haze adds to that of the greenhouse gases, and is hastening the retreat of the Hindu Kush glaciers and snow packs, including the snow that melts to drive Mahabir’s turbines, partly because rising air temperatures are more pronounced in elevated regions. And black unburnt carbon in the filthy clouds is being deposited on these white peaks, reducing their reflectivity and exacerbating ice melt. It’s a reason for the five-times-higher warming rate seen here, oranges growing higher on the slopes towards Nangi, and Mahabir’s overheating yaks.
The dense blanket of pollution hovering shroud-like over Asia is also affecting monsoons and agricultural production. It’s a complex relationship: the soot particles, ozone and water vapour in the haze absorb sunlight, heating the atmosphere, enhancing warming by as much as 50%; while at the same time, the sulphate particulates cool Earth’s surface by shading.10 The shading aerosols alter the global hydrological cycle because less sunlight hits the sea, so there is less evaporation and therefore less rainfall. A decrease of about 40% in the monsoon rainfall over the northern half of India to Afghanistan, and a north–south shift in rainfall patterns in eastern China has already been observed, reducing crop yields.11 The brown cloud also reduces the efficiency of precipitation because it makes it harder for large raindrops to form, leading to drought-like conditions. Its effects can be felt all the way to Australia.
Any changes to rainfall immediately affect plant growth, including agriculture, which is further impacted by particulates deposited on the plant leaves. These reduce the amount of light that gets through, limiting photosynthetic activity, and can also cause acid damage to the plant cells. And elevated levels of ground-level ozone reduce the yield of certain crops including wheat and legumes – one study estimates that the brown clouds have already reduced Indian rice yields by 25%.12
The haze is also a health hazard, linked to an increase in acute respiratory infections, particularly in children; lung cancer; adverse pregnancy outcomes; heart attacks and other conditions. In India alone, it is estimated that nearly 2 million people die each year from conditions related to the brown cloud. Household solid fuel used for cooking, a major source of brown haze, kills more people each year than malaria – wood smoke alone kills more than 1.5 million a year, mostly women and children. By 2050, urban air pollution is set to be a bigger killer than dirty water and poor sanitation, according to the OECD, with 3.6 million premature deaths a year predicted mainly in China and India. In many places where we live, we have turned the planet’s vital fresh air into a poisonous dangerous vapour.
But the atmosphere of the Anthropocene may not be permanently stained. The good news is that dealing with brown haze presents a much easier and faster solution to regional – and global – warming than acting on carbon emissions. The rewards of decreasing soot emissions from biomass combustion could be sizeable and rapid – because unlike carbon dioxide that persists for a hundred years, the brown cloud pollutants only hang in the atmosphere for a matter of days. Slashing black carbon alone could bring an astonishing 40–50% reduction in global warming, and that’s in addition to all the health benefits.13
This would mean more stringent vehicle emissions standards, which many developing countries from China to India are already starting to enforce. And it means fundamental changes to how people cook and warm their homes in places like Kathmandu. Supplying a $30 clean-cook stove to the 500 million households who cook with open fires could be done for just $15 billion. Distributing clean-cook stoves would not only reduce the pollution burden, but also free girls and women from gathering and carrying firewood, a task that endangers their health, puts them at risk of rape and prevents them from going to school. A big win all round.
The pretty village of Phakding, on the busy trekking route to Everest base camp, is immediately different to others I have visited, but it takes me a few hours to realise what is missing. I twig when I spot Ani, the owner of my guest house, cooking on an electric stove: the smoke, which has been a continual presence of every street and house since I entered the country, is strangely absent. I breathe in deeply through my nose to check. There is the faintest whiff of a fire burning on a far-off ridge but otherwise nothing smoky. I can smell the garlic and chillied onions cooking in Ani’s kitchen, the sweet dank smell of drying vegetation mingling with fragrant marijuana and flowers, and the earthy sourness of buffalo manure.
I chow down on vegetable stew with chapatis, and press Ani for details of this smoke-free nirvana. It’s an NGO initiative that has seen the whole village embrace micro-hydropower, using a flowing stream to drive a turbine that produces electricity for the village. ‘We were using more and more kerosene and diesel because of all the tourists that were coming, and it was getting so expensive,’ she says. Initially, when the micro-hydro was suggested, there was scepticism from some of the villagers, who thought that converting to the new energy source would cost too much. After all, those who couldn’t afford the increasingly costly diesel simply chopped wood in the forest and supplemented their fires with dung and other waste. But as more and more tourists came, and the village’s energy requirements rose, the sparse, high-altitude forest was becoming frighteningly depleted. Arguments were brewing between those who wanted to keep the forest for buffalo feed, and those who needed it for fuel.
Micro-hydro has changed all that, Ani says. ‘It powers everything for free – all the lights, the music, cooking. And the kitchen is so much cleaner without the black soot,’ she smiles. The forest has even started growing back. The other villagers I speak to agree that the new energy supply has been an improvement, even if one important controversy remains: whether chapati can ever be properly tasty when cooked on anything other than an open fire.
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