Rise in sea level caused by global warming will sink the earth
About 250 million people occupy land below the current annual food levels. A quarter billion people live just above the high-tide line.
Even if we stop emitting greenhouses gases overnight, the ocean level would still rise to another foot and a half by 2100. The seas might get 2-3 feet higher.
The new estimate suggests that more than three times more coastal residents worldwide are vulnerable to sea-level rise and flooding as compared to the previous studies. That comes to hundreds of millions of people across the planet.
The Real Numbers:
Researchers have used a new method to calculate the height of a building and sea level. It suggests that 110 million people worldwide live below the high-tide line. About 250 million people occupy land below the current annual food levels. A quarter billion people live just above the high-tide line.
"It turns out within those first couple of meters [above sea-level], there are more than 3 million people per vertical inch." says one of the scientists involved in the project.
Even if we are optimistic and the greenhouse emission starts declining from next year, 190 million people would occupy land below sea-level by the end of the century. And if emissions keep on rising through 2100, the number of people below sea-level would rise to 630 million people globally.
The most concerning is the number of people who are living close to the high-tide levels. There are 1 billion people who live less than 32 feet above today's high tide level. A quarter of a billion lives less than 3 feet (1 metre) above that line. The study suggests that if the Earth's temperature increases by more than 3 degrees Celsius, the water level would be 3 feet higher by 2100.
The most affected areas:
Results from the study name continents from Asia to be most affected by the change. It says that by 2050, 237 million people in China, Bangladesh, India, Vietnam, Indonesia, and Thailand could face annual coastal flooding threats. And by 2100, this number could increase to 250 million.
In the 20th century, we have seen a rise in sea level by 6-inches (15 centimetres). Melting of the Antarctic and Greenland ice sheets is the main reason behind the rise in the sea level. These glaciers are melting six times faster than they were melting four decades ago.
The study suggests that Greenland covers 1.7 million square kilometres (656,000 square miles). This is equivalent to three times the size of Texas. If we combine Antarctica, both of these contain 99 per cent of the world's freshwater.
If the Greenland ice melts, it will cause a 23-foot (7 metres) rise in sea level, on average. And if both the largest ice sheets - Antarctica and Greenland - melt, it would increase the sea level by 200 feet (61 metres).
A rise in ocean temperature also caused because of greenhouse gases makes the water expand. As 93 per cent of the extra heat is trapped by oceans, an increase in temperature will cause the sea levels to rise.
Now, you can compare the rise in sea level with the number of people who live close to the high-tide level. A slight increase is going to affect billions of people.
To be exact, the report suggests that higher seas would displace or affect 680 million people in low-lying coastal zones and about 65 million citizens of small island states.
One of the scientists involved in the project says "Even as we show there's a far greater threat from sea-level rise, we now know that there are far greater benefits to cutting emissions,". He also added, "This new data can be a useful tool for cities and countries to plan better for the future their coastal populations are facing.