翻译全文，通顺。以及summary（correct points, use of own words and communicatively clrear sentences）尽量用英式英语. 看满意度加分100~300不等
Floods and Droughts
Periodic floods are as normal as sunshine, although rarely as welcome. According to the United Nations, floods presently affect over 500 million people per year worldwide, resulting in as many as 25000 annual deaths, extensive homelessness, disaster-induced disease, crop and livestock damage and other serious harm. Because of climate change, population growth and unsustainable land use, the number of those vulnerable to catastrophic floods could rise to 2 billion by 2050. The number of major flood disasters has risen steadily; six in the 1950s; seven in the 1960s; eight in the 1970s; 18 in the 1980s and 26 in the 1990s.
The greatest potential flood hazard is in Asia. Between 1987 and 1997, 44% of all flood disasters worldwide affected Asia, claiming 228000 lives (over 90% of all flood-related deaths worldwide). China's vulnerability to massive floods in well-known and helps to account for mammoth building project of the last century that have attempted to control river water and turn it into electric power. Among the most devastating floods in history have been those when the Yellow River in China has overflowed its banks, the great flood of 1887, 1931 and 1959 all killing over a million people. Nothing on this scale has occurred in recent decades, mainly because of the flood defences put in place by the Chinese government, especially on the Yangtze and yellow Rivers.
Devastating floods in Mozambique (2000), Bangladesh (2004) and Bolivia (2006) show that the problem of large-scale inundation is by no means confined to Asia. The most costly flood of recent times was in New Orleans after Hurricane Katrina. Described as the ‘largest civil engineering disaster in the history of the United States’, the storm surge flooding of New Orleans that followed the onslaught of Hurricane Katrina in August 2005 was also a human tragedy of enormous proportions. Over 150000 properties in New Orleans were damaged or destroyed by wind, water and fire, and about 1100 people died.
No country has had to do more to protect itself from flooding than the Netherlands. This lowland country is continuously threatened by the sea and has long been protected by dikes. As far back as 1937 the public works authorities were warning that the dikes would not be enough if a major storm blew up. Their prediction came true in the 1950s when storm surges overwhelmed the dike system, flooded 140000 hectares and drowned some 2000 people. In response, the Dutch government embarked on the Deltawerken, the world’s most ambitious hydraulic engineering system. This system provided a ring of barriers across the mouths of the Rhine, the Meuse and the Schelde rivers, including both fixed dams and giant moveable storm barriers over 20 metres high.
Meanwhile Britain, also hit by storms in 1953, has constructed the Thames Barrier, a series of giant gates that can be closed to protect London from storm surges. Completed in 1984, the gates had to be closed four times in the 1980s, 32 times in the 1990s and 37 times in the period 2000-2004 which is clear evidence that the flood risk to London is growing.
The cost of such defence systems is beyond the reach of poorer countries. Yet Bangladesh, which had floods in 1988 that covered 60% of that country, put in place a Flood Action Plan (FAP) in the 1990s that has greatly reduced the destruction and loss of life that used to accompany the monsoon floods. Higher embankments, improved drainage systems and early warnings have been central to the FAP.
Periodic flooding of rivers constitutes a fact of life across the world. But such floods have become more hazardous with the spread of urban settlements on to natural flood plains. Much of Germany and central Europe suffered terrible floods in 2002, partly because so much of the land along the path of the Rhine had been built upon. The 1993 Mississippi flood, considered the most devastating single flood in US history, also showed what can go wrong when riverside fields are allowed to disappear under concrete. Overloading of the Mississippi delta caused the inundation of 44000sq km of land in nine states, and caused $15bn in damage. Since that time, a further 57sq km of flood plain land has been developed. Similar situations exist in many other part of the world.
In July2005 the city of Mumbai in India was hit by the most concentrated bout of rainfall in the country’s history, 944mm in just 24 hours. Meanwhile, Brazil was enduring its worst drought for 60 years. Such extremes appear to be getting more common and are usually ascribed to climate change.
Too much water is bad enough but too little is even worse. Periodic droughts have been a feature of climate for centuries but in recent years their incidence has grown. Droughts have long been the bane of Africa and help to explain why drought-resistant crops such as millet and cassava are often preferred by farmers to more palatable but water-hungry staples such as rice. The impact of periodic drought in Africa has been increasing as population grows and deserts spread.
In January 2006 the Food and Agriculture Organisation’s (FAQ’s) Global information and Early Warning System warned that food shortages were particularly grave in the four Horn of Africa countries of Somalis, Kenya, Djibouti and Ethiopia, where more than 11m people were estimated to be in urgent need of assistance. In recent years, severe droughts have also affected Ukraine and southern Russia, Spain and Portugal, Australia, Brazil and parts of south and central Asia.