According to the National Oceanic and Atmospheric Administration (NOAA), the annual rate of sea level rise in the 20th century has doubled from 1.4 mm per year in 2006 to 3.6 mm in 2015.

NOAA predicts that sea levels will likely rise by 0.3 meters above the levels seen in 2000 by the beginning of the next century, while the United Nations Intergovernmental Panel on Climate Change (IPCC) estimates that they are It will rise by 40-63 centimeters by 2100.

And if the sea level rises this far, it could cause chaos all over the world.

According to a 2019 study published in Nature Communications, up to 250 million people across all continents could be directly affected by the year 2100.

Gerd Maselink: The disappearance of cities or countries depends on whether we as human beings do something to counter this threat (French)

Countries threatened with disappearance

“The disappearance of cities or countries depends on whether we as human beings do something to counter this threat,” Gerd Masilink, professor of coastal geomorphology at the University of Plymouth in the UK, told Live Science.

"Most of the Netherlands is already below sea level but it is not disappearing, because the Dutch are building and maintaining their coastal defenses," he added.

According to the Union of Concerned Scientists, the Maldives, which consists of 1,200 small atolls and is inhabited by about 540,000 people, will lose about 77% of its land area by 2100 if the sea level rises by only 45 centimeters, because it It rises on average only one meter above sea level.

The country of Kiribati - a small island located in the heart of the Pacific Ocean with a population of about 120,000 people - has a very low average elevation of 1.8 meters above sea level, so Kiribati would lose two-thirds of its territory if the sea level rose by 90 centimeters.

The Maldives is one of the islands in danger of drowning due to sea level rise (websites)

Anyone living on an island in the Pacific Ocean is likely to be severely affected by sea level rise.

According to the Science and Development Network (, as many as 3 million Pacific Islanders living within 10 km of the coast may need to move before the end of the century.

A 2016 study published in Environmental Research Letters reported that sea-level rise has already caused the disappearance of at least 5 "vegetable coral" islands, as well as 6 other islands experiencing severe coastal recession.

According to the EU-funded Life Adaptate project, most of the population in China will be affected by sea level change, with 43 million people living in unstable coastal locations, followed by Bangladesh, where 32 million people will be at risk by 2100. India with nearly 27 million people at risk of drowning.

Thus, it can be argued that millions of people will be directly affected by the consequences of sea-level rise by the end of the century, but it seems unlikely that any country will disappear completely, even those at very low altitudes.

Coastal cities in danger of drowning

Jakarta, the capital of Indonesia, is one of the clearest examples of rising sea levels causing great hardship in the world.

According to the website "" - a non-profit environmental organization based in Hong Kong - Jakarta - with a population of about 10 million people - was named "the fastest sinking city in the world" by the BBC, as It is sinking 5 to 10 centimeters every year due to "excessive drainage of groundwater".

According to the World Economic Forum, a large part of Jakarta could be under water by 2050, and by 2100 Dhaka in Bangladesh (22.4 million people), Lagos in Nigeria (15.3 million people), and Bangkok in Thailand (9 million people could be submerged by 2100). people) completely, or large areas of land will be submerged and unusable.

According to recent forecasts, many American cities may face serious problems by 2050, and large swaths of land are likely to become uninhabitable.

According to research by Climate Central's Research, New York City is considered the most vulnerable, and the report states that by 2050 nearly half a million New Yorkers will live on a "threatened land".

The report also indicated that 36 of the 50 cities in the United States classified among the cities most vulnerable to coastal flooding are in Florida.

Can cities threatened with drowning be saved?

Countries that invest in infrastructure such as the Netherlands may be able to avoid some of the effects of the floods, but some investments such as those proposed in Florida cannot be applied everywhere.

The measures to restore mangrove forests and expand coral reefs proposed by The Nature Conservancy are only feasible in specific climate zones, and they are very expensive.

According to The New York Times, officials in Miami-Dade County, Florida, recently announced a strategy that includes "raising homes and roads," as well as creating an open space that allows flooding without damaging infrastructure.

While the United States may be able to invest in coastal protection projects and have the ability to learn through trial and error, most developing countries cannot.

The United States may be able to invest in coastal protection projects when most developing countries cannot (Getty Images)

"Bangladesh is unlucky compared to countries like the Netherlands and the United States in terms of having the financial leverage to implement such projects," Masinic said.

He added, "The country may have a low altitude above sea level, but it is prosperous and politically stable, which guarantees its safety and continuity for decades to come, but it will not be able to withstand the sea if it is poor and unstable."

Thus, it can be said that the main factor in determining whether a city will disappear is not necessarily the rate of sea level rise, but mainly related to its ability to address the problem and develop long-term defenses.

"It is difficult to predict what will happen to our planet in 100 years, in addition to the uncertain rate of sea level rise - which is highly dependent on greenhouse gas emissions - the main factor is the measures and plans that states and society intend to implement to mitigate sea level rise," Masylink said. ".