The level of the planet's seas may rise at least six meters compared to the current sea level, "engulfing" many coastal cities, even if governments work together to decrease the temperature rise to a maximum of two degrees Celsius in relation to pre-industrial levels.
This new warning from scientists, which, however, does not concern the near future, is based on a new study showing that over the past three million years the water levels of the Earth has repeatedly risen above six meters because of the melting ice.
The researchers of the international consortium ‘Past Global Changes’ studied the data of the last three decades regarding the changes in the ice of Antarctica and Greenland in the past and their impact on ocean levels.
The main conclusion is that even small climatic changes are enough to lead to a significant increase in water and even an increase of six meters is something not unusual in the planet's climate history. Given the accumulation of hundreds of millions of people in coastal areas, such a rise in water would be terribly destructive to lives and infrastructure.
According to the researchers, the level of carbon dioxide in the atmosphere today is about the same as it was three million years ago, when the sea level was at least six meters higher than today. Therefore, according to scientists, it may be a matter of time something similar to happen in our time, even if there is a relatively successful containment of climate change and carbon dioxide at current levels or slightly higher.
125,000 years ago, when the ice had melted, the water had risen six to nine meters, and 400,000 years ago, when there was a warm period (the average temperature was only one degree Celsius higher than today) and melting ice, the level of the water had risen from six to thirteen meters.
Today the ocean level is about 20 cm higher than pre-industrial levels. The countries which are expected to be most affected by the rising waters, are China, Vietnam, India, Indonesia, Bangladesh, Japan and the USA.