Climate change: a survivors' guide
Britain is expected to get more extremes of heat and rainfall, so prepare for more severe floods, longer droughts and more powerful storms. No one knows quite what the effect over time will be of a slowing Gulf stream, or the melting of arctic sea ice, but climate scientists confidently expect temperatures to rise up to 4C by 2100 . That could mean big shifts in rainfall patterns and a more unpredictable climate. So clear your drains, fix your roof and move to Wales or at least to somewhere with good water supply. The worst that could happen? Your grandchildren will inherit inexorably rising temperatures that render much of the Earth uninhabitable. Their problem? Yes, but yours, too. Sea levels are rising gradually and by the end of the century could be nearly 2ft higher than they are today . So don't pass on that beach hut to your children, and expect to lose acres if you live near the coast in East Anglia and other low lying areas. You won't have to head for the hills for many years, but prepare to view the seaside from behind higher walls and from the dykes that will be needed to protect many coastal towns. By 2100 the map of Britain will be smaller and many cities are likely to be besieged by climate "refugees" arriving from low-lying areas such as Norfolk. Climate change is going to be very, very expensive, and the poor, the old and the vulnerable will be the most affected because they are least likely to have the money to move house or adapt. Economists such as Lord Stern and Jim Yong Kim , the new president of the World Bank, expect a 4C temperature rise to result in global economic meltdown unless countries rapidly shift their economies towards less energy-intensive industries. Stern predicts that warming will knock at least 5% off GDP per year and Kim expects food shortages and conflicts over natural resources and water. Abnormal events such as Hurricane Sandy , which cost $65bn (40bn) and the 2011-12 US drought, which cost $35bn (21bn) may be just foretasters of the price to be paid. On the other hand, there's serious money to be made adapting cities and industries to climate change and reducing emissions. More heat and a longer growing season should make it easier to grow some crops in northern countries such as Britain, Russia and Canada, and more carbon dioxide in the atmosphere theoretically should increase plant growth . But don't expect climate change to feed the world. You are likely to have to change diets because bigger droughts, flash floods, heatwaves and storms may devastate harvests and reduce the amount of foods available. Countries such as Britain, which depend heavily on food grown abroad, may be able to grow fruit that farmers only ever dreamed about, but there will be less land on which to grow and imported grub will be much more expensive because other climate-affected countries will keep their smaller harvests for themselves. If coral reefs vanish there will be fewer fish in the sea and if the oceans continue to soak up CO2 they will become more acidic. That would be very, very bad, but the scientists say this won't impact heavily in the next few lifetimes. Don't take fresh water for granted . Longer droughts are likely to dry up large parts of southern and eastern England, and underground water suplies will be more stressed. We've always muddled through heatwaves and droughts, but as temperatures climb, a run of dry winters becomes more and more likely. So prepare for droughts not just once a decade but perhaps every other year. Get used to yellow lawns, taking showers with chums and watering your garden with waste water. Humanitarian groups such as Oxfam expect many more food shortages and natural disasters in countries where even a small shift in the rainfall pattern or increase in temperature is enough to reduce harvests and leave millions more hungry. Worst-case scenarios? A shift in the Asian monsoons is expected to reduce the amount of water in rivers coming off the Himalayas, and because this is needed for nearly a third of the world's population, there could be disastrous food shortages. Further drying out of the Sahel and African rangelands will force millions of people to move. Things are going to go wrong much more often, so expect mini-disasters. Cars, trains, roads, and buildings, flood barriers, drains, underground systems, reservoirs, power stations, ports and all are designed for existing temperatures, sea levels and rainfall, and may be overwhelmed in future . Railway lines will buckle more easily, nuclear power stations will get flooded more easily, building cooling systems will be inadequate, flat roofs will leak more and concrete structures will be like ovens. Designers will have to rethink the way things are made. Warmer winters mean fewer deaths among the old, but far more heart and respiratory diseases in the hot summer nights . Even worse, the warmer, wetter conditions will encourage the fungal, algal, tick-and-mosquito-borne diseases we usually only see in the tropics: Dengue fever was detected in France and Croatia in 2010; West Nile virus and Rift valley fever have become common in the US; and a 4C increase in Britain probably means malaria-carrying mosquitoes, and ticks infected with Lyme disease. Equally possibly, the already crumbling system of urban drains is likely to be overwhelmed by extreme weather events, which will discharge pathogens into heavily used rivers and seas, possibly heralding the return of diseases such as typhus. Life in many of the world's cities is already nearly unbearable in some months. The scorching urban nights expected with climate change will be a recipe for social disorder, illhealth and mass grumpiness. If there are water and power cuts, as expected, then get ready for migrations out of urban areas to cooler countryside. Best advice? Stay out of town. A 4C temperature rise doesn't sound much, but it is quite enough to kill off trees, wildlife, garden plants, insects, and river life . On the positive side, we may get faster-growing rainforests and enhanced plant growth, but many animals will not be able to adapt to higher temperatures. Don't expect to grow the same plants in your garden, or see the same trees in the parks. Change will be gradual, but profound.