英语音频杂志：天气

 　　Weather

　　
　　by Mike Rayner
　　It's hardly surprising that weather is a favourite topic for so many people around the world - it affects where we choose to live, what we wear, our moods, and perhaps even our national characteristics. A sunny day can relieve the deepest depression, while extreme weather can destroy homes and threaten lives.
　　
　　The effects of weather
　　Palm trees bent 1 double in hurricane force winds, cars stranded 2 in snow drifts, people navigating 3 small boats down flooded city streets – images we are all familiar with from news reports of severe weather spells. But many of the effects of the weather are less newsworthy.
　　‘I’m feeling a bit under the weather’ is a common complaint in Britain, especially on Monday mornings, and it seems that weather really can be responsible for moods. Studies have shown that changeable weather can make it hard to concentrate, cloudy skies slow down reflexes, and high humidity with hot, dry winds makes many people irritable 5 and snappy.
　　Some suggest that the weather also leaves its mark on character, giving people from the same region similar temperaments 6, although it seems that economic, political and social factors are likely to have a much stronger effect than the weather.
　　
　　What causes changes in the weather?
　　If you live in a place like Britain, where the weather seems to change daily if not hourly, you could be forgiven for thinking that the weather is random 7. In fact the weather is controlled by systems which move around areas of the globe. In the UK the weather depends on depressions, often called ‘lows’, and anticyclones, also known as ‘highs’. These systems start in the Atlantic Ocean, and make their way across the British Isles 9 from the west to the east. Highs bring sunny weather, while lows bring rain and wind.
　　The weather systems in tropical climates are very different from those in mid 4 and high latitudes 11. Tropical storms develop from depressions, and often build into cyclones 8, violent storms featuring hurricanes and torrential rain.
　　In modern times, human activity seems to be altering weather patterns. Gases produced by heavy industry change the temperature of the Earth’s surface, and affect cloud formation. Some researchers say that factories in Europe and North America may have been one of the causes of the droughts in Africa in the 1980s.
　　
　　Can we predict the weather?
　　The human race has always tried to guess the weather, especially in areas of the world where there are frequent changes. Traditional rhymes point to early attempts to identify weather patterns, popular poems include:
　　Red sky at night, shepherds’ delight; Red sky in the morning, shepherds’ warning
　　Ash leaf before the oak, then we will have a summer soak; Oak leaf before the ash, the summer comes without a splash
　　Flies will swarm 12 before a storm.
　　Rain before 7, clear by 11.
　　Two other popular traditional ways of forecasting the weather used pine cones 14 and seaweed. When the air has a high level of humidity there is a higher chance of rain, when the humidity is low, there is more chance of fine weather. Pine cones and seaweed react to changes in humidity - pines cones open, and seaweed feels dry when the humidity is low, while high humidity has the opposite effect.
　　While folk wisdom can still provide a guide to help forecast weather, today’s methods of prediction increasingly rely on technology. Satellites, balloons, ships, aircraft and weather centres with sensitive monitoring equipment, send data to computers. The data is then processed, and the weather predicted. However, even this system cannot predict weather for longer than about week.
　　A recent study by an Australian psychologist suggests that certain people may have a special gift for predicting the weather. However it is possible that these people would use their talent in another way, since the same group had considerable success in forecasting changes in another chaotic 15 system – the stock market.
　　It appears that a study of weather patterns may also enable scientists to predict the outbreak of disease. An Ebola epidemic 16 in Uganda in the year 2000 came after the same rare weather conditions that had been present before an outbreak 6 years earlier. Efforts to limit the spread of airborne diseases such as foot and mouth, are also strongly dependent on favourable 17 wind conditions.
　　
　　Extreme weather
　　Although people in Britain often moan about the weather, we should spare a thought for the inhabitants of parts of the world where extreme weather regularly wreaks 18 havoc 19 on the environment and population. Sandstorms, tornadoes 21, blizzards 23 and flashfloods regularly kill thousands of people and leave many others homeless.
　　While most of us try to avoid extreme weather, some adventurous 24 souls actively 25 seek out places where extreme weather conditions exist. Sports such as surfing, kiteboarding, ice-climbing and white-water rafting are becoming increasingly popular with people seeking relief from the monotony of daily routine. Extreme sports are about exhilaration, skill and danger, and often harness the weather to provide adrenaline addicts 26 with their kicks.
　　Even more extraordinary are storm-chasers – weather enthusiasts 27 who risk their lives following tornadoes and thunderstorms at high speed to witness the damage they cause at close hand.
　　
　　Glossary 28
　　adrenaline (n): a hormone 29 produced by the body when you are frightened, angry or excited, which makes the heart beat faster and prepares the body to react to danger.
　　ash (n): a forest tree which has a smooth grey bark, small greenish flowers and seeds shaped like wings.
　　blizzard 22 (n): a severe snow storm with strong winds.
　　climate (n): the general weather conditions usually found in a particular place.
　　drought (n): a long period when there is little or no rain.
　　humid (adj): (of air and weather conditions) containing extremely small drops of water in the air.
　　hurricane (n): a violent wind which has a circular movement, especially found in the West Atlantic Ocean.
　　latitude 10 (n): the position north or south of the equator measured from 0° to 90°.
　　oak (n): a large tree that is common especially in northern countries, or the hard wood of this tree.
　　pine cone 13 (n): the hard egg-shaped part of the pine tree which opens and releases seeds.
　　psychologist (n): someone who studies the human mind and human emotions and behaviour, and how different situations have an effect on them.
　　reflex (n): an uncontrollable physical reaction to something.
　　shepherd (n): a person whose job is to take care of sheep and move them from one place to another.
　　tornado 20 (plural tornados 30 tornadoes) (n) (US INFORMAL ALSO twister): a strong dangerous wind which forms itself into an upside-down spinning cone and is able to destroy buildings as it moves across the ground.
　　torrential (adj): used to refer to very heavy rain.