Adventures in the Anthropocene - Gaia Vince

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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.

      The glacier that feeds the village’s micro-hydro sits high in the mountains, a dirty apostrophe surrounded by snowy peaks on Nepal’s northern border with Tibet. ‘We used to play on the glacier as children, and it came right down to the monastery,’ says Ringin Laama, a local yak herder. ‘But now it’s about two kilometres further back.’ The mountainside beneath the glacier is heavily scarred, clearly marking its original extent on the rocks. Every year, the glacier retreats much further, according to Laama. ‘I think it will be completely gone in ten years’ time,’ he says. ‘Strange to think.’

      Curved walls made of large boulders have been constructed along the mountain face above each small cluster of houses. The ground here used to be permanently iced all year, and the melting has exposed fissures in the rocks. The Himalayan mountain range – the ‘Abode of Snows’ in Sanskrit – is one of the youngest on Earth and it’s still highly energetic with active seismic and tectonic processes. Landslides, already common here, are becoming more frequent in the warming climate, with deadly consequences. Laama traces a large scratch in the mountain opposite with his finger. It extends down through the rubble of former houses and terminates in a huge boulder.

      Elsewhere, landslides are damming up rivers, resulting in a build-up of water. The risk then is of a catastrophic release: a flash flood that occurs rapidly, with little warning and transports vast amounts of water and debris at high velocity. Every year, hundreds of people die – in 2002, flash floods and landslides killed 427 people in Nepal and caused $2.7 million-worth of damage.

      Glacier-fed rivers are set to swell over the next decade as melting accelerates. But it will be a short-lived sufficiency – once the glaciers have gone, there will be no more meltwater. It means that the turbines that power Ani’s kitchen will lie still. Perhaps anticipating this, some of the villagers have invested in a rival cooking source, supported by another NGO. I visit the home of Alok Shrestha, a man so self-sufficient he makes methane cooking gas from his household’s sewage, animal manure and other waste, which are shovelled into a biodigester under his house. The biodigester is a large feeding box for bacteria, which metabolise the nutritious waste and produce useful methane in the process. Shrestha taps this for his cooking stove and has plenty left over to power lighting and a small generator that recharges batteries.

      I have visited several homes around the world where people are making their own biogas from a range of wastes, including one in Peru that was powered by guinea-pig poo, and all fuel efficient cooking stoves with smokeless flames. Firing up a stove for brief, if regular, intervals is one thing; powering equipment that requires a continual source of electricity is another. For example, the hydroturbine on which the hopes and dreams of Mahabir’s Pun tribe rest is powered by a stream fed by snowmelt higher up. No snow means no meltwater and no power, and levels have been diminishing in the once-deep stream. When the water fails, the development of that entire region, which outstrips its neighbours on every measurable scale from literacy to health, will be at the mercy of the government for grid provision.

      The government has just a few years to build enough reservoirs to trap the melting waters and power the country towards twenty-first-century development, before lights go out. It is hard to see how that will happen. Drought conditions are already causing

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