The ocean covers 70.8% of the Earth's surface.That share is____1____ up.Averaged across the globe, sea levels are 20cm higher today than they were before people_____2___suffusing the atmosphere with greenhouse gases in the late 1800s.They are ____3____ to rise by a further half-metre or so in the next 80 years; in some places, they could go up by twice as much-and more when amplified by storm____4____ like the one that Hurricane Sandy propelled into New York in 2012.____5____ flood plains are expected to grow by 12-20%, or 70,000-100,000 square kilometers, this century.That area,____6____the size of Austria or Maine, is home to masses of people and capital in booming sea-facing metropolises.One in seven of Earth's 7.5bn people already lives less than ten meters above sea lev-el; by 2050, 1.4bn will.____7____atolls like Kiribati may be permanently submerged.Assets worth tril-lions of dollars—including China's vast manufacturing cluster in the Pearl river delta and innumer-able military bases—have been built in places that could often find themselves underwater.
The___8_____ of the sea level is not mysterious.Seawater expands when heated and rises more when topped up by melt water from sweating glaciers and ice caps.True, scientists debate just how high the seas can rise and how quickly and politicians and economists are at odds____9____ how best to deal with the consequences—flooding, erosion, the poisoning of farmland by brine.Yet argument is no____10____for inaction.The need to adapt to higher seas is now a fact of life.
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