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Our world in 2050
When scientists scan the global horizon, overfishing, loss of species habitat, water shortage, climate change, and invasive species(外来物种)seem to be the biggest threats to the earth.What will our world be like in 2050?
Population Decrease and Increase
There are two features(特征)in the growth of world population.The United Nations estimates(预计)that by 2050, the population of European countries will decrease from the current 0.72 billion to 0.63 billion.Second, the population in developing counties is growing rapidly.By 2050, the population of Africa is expected to reach 1.8 billion, 0.9 billion more than its current population.
Global Warming
A recent research report published by the Unites Nations indicates that it is quite possible that the earth’s temperature is rising well above the previous estimate.
A research team from the University of Colorado used satellite data to estimate that the ice sheet will lose up 48 cubic miles by2050.In comparison, a city the size of Los Angeles uses one
cubic mile of fresh water every year.Ice shelves in Antarctic will have decreased by more than 7,200 square miles in the next four decades(十年)
Water Shortage
Africa's rivers face dramatic change that will leave a quarter of the continent severely short of water by the middle of the century, according to a global warming study published today.
If you're already walking 5 km to the nearest stream to get water, by 2050, it's going to mean walking 30 km or moving your whole household closer to the water source.
Four Wheels Good, Four Wheels Bad
The car has transformed(改变)the lives of people, but the planet is paying too high a price.Today there are 620 million private cars worldwide, to say nothing of buses, vans and lorries.With current growth trends that by 2050 there will be about three billion cars.
And by around 2050, the levels of carbon dioxide in the atmosphere will reach 550 ppm(pats per million).Car using will increase global temperature between 1.4℃ and 4.8℃ and the sea levels will rise between 0.09 and 0.78 meters.