How Can I Stop Climate Change: What is it and how to help - Литагент HarperCollins USD

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to decline by anything from 30 to 90 per cent by the end of the century, leaving growers at the mercy of unreliable rain. ‘We are way out of control,’ says Annie. ‘We are changing things and we do not know what is going to happen. That is pretty scary.’

      climate crisis in Africa

      Farming is the backbone of most African economies. Four out of five Africans live in the countryside and farm or keep livestock for their livelihoods. As extreme weather hits the continent some of the world’s poorest people are bearing the brunt of climatic shifts. Eastern and Southern Africa have been badly affected by changes in rainfall. Until recently the rainy season would normally arrive in April and May but it hasn’t done so since 2002. Rivers and irrigation canals are running dry.

      According to development agencies such as Christian Aid many people in rural areas are living on the edge of starvation. As temperatures rise, declining crop yields could leave hundreds of millions unable to produce or purchase enough food. In 2006 nearly 4 million

      people in Kenya needed emergency food aid and millions of cattle perished following three consecutive years of failed rains. Lack of rain and grazing for animals is destroying the way of life for cattle-herders, fishermen and farmers, who find themselves competing and sometimes in conflict over a dwindling resource. Without food or crops to sell, people are struggling. Those with livestock or access to pasture have to defend it from those without. In northern Kenya, shepherds carry automatic rifles. Others survive only with the help of food aid. Some turn to the towns and cities in search of an alternative living, often leaving children with grandparents to work the land.

      SHARE ISSUE:

      The early impacts of climate change are being felt by the people least responsible for bringing it on. The IPCC predicts mounting pressure on water resources, and a halving of yields from rain-fed agriculture for some African countries by 2020.

      water shortages in Kenya

      ‘When I was young there were grazing fields, water, milk, blood and meat,’ says Lore Kapisa who heads a family of 20 in Turkana, Kenya. ‘But we have seen huge changes over the past ten years: our livestock have died, our grazing fields have shrunk and our water dried up.’ The people in Turkana have lived in the arid terrain in the north-west corner of Kenya by farming animals. Lore has struggled for the past ten years because of relentless drought. As water and pasture become scarcer, disputes between neighbouring groups are spiralling into violence and Lore now carries an automatic rifle to protect his herd. But rather than food aid Lore wants water, pasture and a vet. This, he says, would enable them to continue their traditional ways of life. ‘We have been sick and without food, but we are human beings capable of being productive. Food aid creates dependency and reduces us to lesser human beings.’

       Chapter 2

       the science of climate change

      We know climate change is happening, but what’s causing it? This chapter looks at the facts behind the freaky weather, and the implications for our planet if things carry on as they are.

      why climate change is happening

      Vital signs Three charts that tell a story – as global temperatures and sea levels have risen snow cover in the northern hemisphere has shrunk. The red lines give a bird’s eye view of key changes over the past 150 years based on yearly measurements (the grey dots), while the narrowing blue bands shows the room for doubt declining as measurement techniques have improved. Source: IPCC.

      the greenhouse effect

      Most life on Earth relies on energy from the sun to provide warmth and light. Some of the sun’s energy reflects off the Earth’s surface in the form of infrared rays, and gases in the atmosphere trap and/or reflect this energy - just as glass keeps heat in a greenhouse. The greenhouse effect helps keep the Earth warm enough to support life.

      But some of these gases, particularly carbon dioxide, are building up because of pollution created by human activity. The result is more trapped heat and a sharp rise in the rate of warming.

       SUN TRAP:

      A thin blanket of gases around the Earth prevents some of the sun’s energy from escaping back into space.

       five warming signs

      Higher temperatures: Scientists have established that the global average temperature has increased by 0.76°C in the past century. Records going back over 150 years show that globally 19 of the 20 hottest years have occurred since 1980.

      Melting ice: Arctic and Antarctic ice is thinning and sections of ice shelves are breaking off completely. Temperatures in the Arctic are rising twice as quickly as the global average.

      Coral bleaching: Scientists have found a rise of 2°C can kill coral. Reefs are home to around a quarter of known marine species.

      Rising seas: We saw an increase of 17 cm during the 20th century.

      Drier: Droughts have become more intense over the past 30 years, and have lasted longer, particularly in the tropics and sub-tropics.

      fossil fuels and the greenhouse effect

      Plants, trees and ocean plankton containing carbon absorbed many millions of years ago fossilised underground to form oil, coal and gas. When these are burnt the carbon is released, and combines with oxygen to form carbon dioxide. The first person on record to recognise the power of fossil fuels to change the climate was Svante Arrhenius, a Swedish scientist who published his ‘greenhouse law’ in 1896. Arrhenius estimated that doubling carbon dioxide levels in the atmosphere would lead to a rise in temperature of 5 °C and thought this promised a warmer climate in colder parts of the world. His maths wasn’t far off but few people today would agree with his predictions that rising temperatures are a good thing.

      greenhouse gases

      The greenhouse gases include carbon dioxide, methane, nitrous oxide ozone, water vapour, sulphur hexafluoride and halocarbons. They make up quite a small proportion of our atmosphere; some have a more powerful warming effect than others.

      carbon dioxide

      Carbon dioxide (CO2) is naturally occurring. People and animals produce it when breathing out whereas plants absorb and metabolise it, releasing oxygen in return.

      The level of carbon dioxide in the atmosphere is measured in parts per million (ppm); or simply by weight (kg, tonnes).

      Scientists believe carbon dioxide levels have been much higher in the Earth’s distant past. Geological evidence suggests that in the Cretaceous period (65-144 million years ago) it was three to six times higher than today.

       RING LEADERS:

      Trees are in the frontline of defence against climate change – the vast sub-arctic forests of the north being among the most important. The United States, for instance, would be having an even greater impact on global warming if its forests weren’t absorbing around a tenth of its carbon dioxide emissions.

       The world was also 10-15 °C warmer then and there was no ice at the Poles. For much of the time that people have been on Earth, carbon Carbon moves between

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