Some of the most beautiful and highly-populated coastal cities around the world risk to go under water due to sea level rise. Why is this happening?

According to the survey of Geophysical Research Letters, ice is melting at the poles, water is approaching the equator and accumulating there under the influence of gravity. As a result, in the tropics water level rises more than in the northern regions.

Houston, Texas

Houston is the biggest city in Texas and the fourth by population in the US. It regularly suffers from flooding.

Harvey is the most powerful hurricane that has ever attacked the continental territory of the United States over the last 10 years. It caused catastrophic floods in Houston in 2017. Due to frequent downpours, accompanied by hurricanes, rivers overflow their banks. Floodwater breaks down trees, rolls cars over and destroys thousands of buildings.

Some Houston areas are sinking at the speed of 5 cm per year caused by excessive groundwater pumping.

Dhaka, Bangladesh

Bangladesh’s coastal lands face major consequences of global warming during summer monsoon period.

Much of the country’s land is only a few metres above sea level. That is why annually over 22 thousand square kilometers of the land is under threat of flooding. Continuous deforestation contributes to increasing risks of ecological disaster.

According to the United Nations Environmental Program, if the water level rises just by 1.5 metres, Dhaka, together with its nearest settlements, will drown, leaving over 18 mln people homeless. Sundarban, the largest mangrove forest on our planet, will also be doomed.

Venice, Italy

Floods, the so-called alta aqua (high water), occur regularly in Venice. As a result, the city goes under water at a speed of up to 5 mm per year. If the World’s Ocean rises by just a metre, nothing will remain from this well known city of romance, registered on the UNESCO World Heritage List. 

The situation is aggravating due to excessive tourist flow. The ancient beams that support the buildings are almost sagging under the feet of tens of millions of travellers.

In this regard, the Italian authorities are discussing a bill to restrict visits to the city imposing a fee. They are planning to build new dams to support buildings and avoid serious damage.

Virginia Beach, Virginia

Recent scientific studies have proved that around 1400 American cities are in danger of going under water with the state of Virginia first in line.

Virginia Beach has one of the fastest rates of sea level rise on the east coast. The experts of the US National Oceanic and Atmospheric Administration believe that sea level in the city is going to increase 30 cm by the year 2100.

Bangkok, Thailand

Many Asian cities deal with overflows, and Bangkok is not an exception. According to The Guardian, it is going under water at a speed of more than 1 cm per year and may be below sea level by 2030.

In recent years, measures have been taken to reduce the use of groundwater. However, it is impossible to completely stop the sagging of the city. Tropical cyclones and hurricanes, accompanied by devastating floods, are the norm rather than an exception.

New Orleans, Louisiana 

New Orleans, hit by the devastating Hurricane Katrina in 2005, is still recovering. Back then, powerful streams washed away some houses from the foundations and moved them several quarters away. That is why there is no guarantee that this will not happen again. 

Based on NASA research in 2016 and U.S. Geological Survey data, the city is sinking at a speed of 5 cm per year and can completely drown by 2100. Its major territory will be 2.5-4 metres below sea level.

The Netherlands

Apart from cities, entire countries, such as the Netherlands, can go under water.

According to The New York Times, 90% of Rotterdam’s territory is below sea level and Amsterdam has long surpassed Venice in the number of bridges and canals.

In an attempt to save numerous medieval buildings from water destruction, the authorities of Amsterdam are introducing the latest engineering innovations (floodwater spillways). But the fact is that the city is going under water by almost 8 mm per year, leaving tourists less than 10 years to visit this unique water corridors. In about 150 years, with the 2 m increase in water, Amsterdam will be completely flooded. 

Alexandria, Egypt

Today, several historical sights testify to the former greatness of the capital of Ptolemaic Egypt. The majority of artefacts are hidden in the waters of the Mediterranean Sea and the sands of deserts. Despite all this, Alexandria remains one of the most beautiful places in the world.

Scientists believe that by 2100, the level of the Mediterranean Sea will rise by 60 cm. It means that ancient Alexandria which have seen a lot of natural disasters, conquests and sieges in its history, will again be on the brink of extinction.

Miami, Florida

Miami’s territory together with its fashionable beaches is in danger of sinking. The scientists of the US National Oceanic and Atmospheric Administration are trying to simulate the rise of the World's Ocean waters and find out what are Miami’s chances in the fight against the element.

Considering that there are limestone rocks under the city, the water will easily concentrate in the centre causing devastating floods. Besides, underground freshwater reserves are depleting every year.

Jakarta, Indonesia

The capital of Indonesia is built on marshy grounds at the mouth of the Ci Liwung River that flows into the Java Sea. The proximity of Jakarta to the sea together with 13 rivers plays an important role in the development of the city. At the same time, close vicinity to water causes flooding of the territory of Jakarta at an enormous speed - up to 17 cm per year. Еhe downtown of this heavily populated city, which is completely below sea level, will go under water by 2050, experts say.

Indonesian authorities are promoting a bill to build an external sea wall with artificial islands. An artificial lagoon could save the city from flooding, but recently the effectiveness of such a solution has been in question.

The ban on the groundwater pumping will not solve the situation either since it is not beneficial to the authorities and can cause social disaster among city’s population. Such a prohibition will also seriously affect business development in the country. The city needs an alternative source of fresh water.