Rising sea levels will pose a serious threat to human civilization by inundating not only large expanses of arable land, but also some of the world’s largest cities.
More than 100 million people live within 1 meter (about 3 feet) of sea level.
Furthermore, experts are predicting that there could be at least 150 million environmental refugees by 2050.
The Main Causes
The melting of glaciers in Greenland as well as the melting ice caps of Antarctica are mainly responsible.
On the other hand, the melting ice caps in the North Pole are not contributing to the rising sea levels. This is because the ice is not as thick, and that it floats on the Arctic Ocean.
Rising sea levels threatens some of the world's largest cities
Ice Sheets of Antarctica
About 98% of Antarctica is permanently covered in ice. On average, this ice is at least 1 mile (1.6 km) in thickness.
This cold continent contains roughly ninety percent of the world’s ice and about seventy percent of the world’s fresh water.
The world’s oceans will rise by at least ten meters (around 32 feet) if the Antarctic ice sheet melts and falls into the sea.
This alone will cause many coastal areas to be inundated.
Photo by Andrew Mandemaker, taken on January 20, 2006
Glaciers in Greenland
If all the glaciers in Greenland melt, sea levels worldwide will rise by over twenty feet.
Sadly, the latest reports from scientists inform us that these glaciers are melting far faster than they had anticipated.
In fact, scientists recently reported that ice all across the vast glacial interior of Greenland is rapidly melting, a phenomenon that has not occurred in the last 150 years.
In truth, this sudden turn of events baffled scientists.
Currently, there is no place on Earth that is changing more quickly than Greenland.
In addition to rising sea levels, this melting will also cause a change in
weather patterns.
NASA's James Hansen, the world's foremost climatologist warns that "If the world allows a substantial fraction of the Greenland ice sheet to disintegrate, all hell breaks loose for eastern North America and Europe."
Other Causes
As temperatures increase, sea levels will rise directly because of a phenomenon known as thermal expansion.
Moreover, as more glaciers melt, less of the sun’s energy is reflected away from Earth which will cause temperatures to rise even more.
This is known as a positive climate feedback loop.
Future Predictions
In the twentieth century, sea levels rose by 6.7 inches.
In addition, the Intergovernmental Panel on Climate Change predicted in 2007 that sea levels could rise by about 7.1 to 23 inches (18 to 59 cm) in the course of this century.
However, these projections don’t take into account the "uncertainties in climate-carbon cycle feedbacks nor do they include the full effects of changes in ice sheet flow."
Hence, the latest projections state that sea levels could in fact rise by at least one meter during the 21st century.
The Dire Consequences
The slightest rise in sea levels will cause severe floods in low-lying coastal areas worldwide.
These floods will impact agriculture and contaminate fresh water sources with salt water.
It should also be mentioned that the combination of rising sea levels, changes in weather patterns, and an increase in both the frequency and strength of tropical storms would be absolutely devastating to coastal regions.
According to the Internal Displacement Monitoring Centre, there were more than 42 million refugees in Asia and the Pacific during 2010 and 2011 due to rising sea levels as well as other disasters enhanced by abrupt climate change.
Currently, there more environmental refugees around the world than both war and political refugees combined.
With rising sea levels, there will be millions more which will have very strong social, political and economical effects.
Without doubt, it is our moral duty to help stop climate change and to spread the word on mankind's great challenge.
If we don't, the effects of climate change will have a tremendous impact on human civilization.
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