The Countries at Risk From Rising Sea Levels

Rising sea levels are perhaps the most severe consequence emerging from the ongoing climate crisis.

The ocean is absorbing more than 90 percent of greenhouse gases being pumped into the atmosphere. This is causing the sea water to expand. Also, as the world warms, glaciers and ice sheets are melting, feeding into the world’s oceans.

The scary thing? This is all happening at an alarming rate. And scientists fear that it could get out of hand if the effects of climate change are not mitigated immediately.

“Sea level rise is best thought of as sooner or later. Current rates globally are 4 millimeters/year which in a century is 40 centimeters, or about 16 inches. But generally this is expected to increase and we could get up to about 2 feet by 2100, but sooner or later we will get to 2 feet and more,” Kevin Trenberth, a distinguished scholar at the National Center of Atmospheric Research (NCAR) in Boulder, Colorado, told Newsweek.

“Even if we stop global warming by cutting emissions to net zero, sea levels continue to rise for centuries.”

Even a small rise in sea levels has the potential to devastate certain regions. This means if action is not taken, the world could look very different in just a few decades’ time.

In fact, the effects of rising sea levels have already been seen. Rising sea levels can contribute to more devastating storm surges during powerful hurricanes and typhoons—many of which we have seen across coastal regions.

So where can we expect to see these drastic changes and what countries are most at risk?

What Countries Are Most at Risk?

“Sea level rise poses a significant threat to low-lying coastal areas and coastal communities. As sea levels continue to rise, coastal areas are at risk of flooding, coastal erosion and salinization of soils and water sources. Erosion and flooding can damage infrastructure, homes, and businesses, and even displace people from their homes. Areas particularly at risk from sea level rise are low-lying coastal regions and small island nations,” Zita Sebesvari, senior scientist at the United Nations University—Institute for Environment and Human Security (UNU-EHS), told Newsweek.

This includes areas along the East and Gulf Coasts of the U.S. Scientists have predicted that sea levels along the U.S. coastline could rise by up to a foot by 2050.

A study published in the journal Nature Communications in April 2023, found that the sea level rise rate along these coasts is “unprecedented in at least 120 years.” Flooding is expected to drastically worsen in 2050, as the sea level continues to rise.

Other low-lying coastal regions are also at risk. Sebesvari said other vulnerable areas include Bangladesh and Vietnam.

“River deltas are a type of low-lying coastal area specifically at risk. Deltas are often home to many people and are essential agricultural areas due to their fertile soil. However, they are low lying and prone to flooding and at risk to saltwater intrusion. Consequently, the most vulnerable delta regions include the Nile Delta, the Mekong Delta, the Ganges-Brahmaputra Delta and the Mississippi Delta,” Sebesvari said. “Many of the world’s largest cities are located on or near coastlines, making them particularly vulnerable to sea level rise. Some of the most at-risk cities include New York City, Jakarta, Tokyo, Shanghai and Mumbai.”

Jakarta was dubbed the “fastest-sinking city” in the world by a 2018 BBC report. The World Economic Forum predicted in 2019 that the city could be underwater by 2050.

The NYC Panel on Climate Change also predicts that the water around New York City could rise by between 8 and 30 inches by 2050. As one of the world’s most populated cities, this could be devastating.

California is also at risk of coastal erosion as sea levels rise, Trenberth said.

A study published in the journal Environmental Science & Technology on May 2 this year, found that hundreds of hazardous sites on the California coast, including sewage treatment plants and gas and oil facilities, will flood more regularly as sea levels rise. With the increased number of storms being seen as the climate crisis worsens, this could cause hazardous chemicals from these facilities to seep out into the environment.

The effects of rising sea levels have already started to manifest from an increase in storm surges. An example was Storm Sandy, a devastating tropical hurricane which hit New York City on October 29, 2012. The storm caused surges into the East River, which subsequently caused floods reaching up to 14 feet in some areas.

Hurricane Ian also revealed issues in Florida, Trenberth said.

“More generally, any low lying areas that were once deemed great spots but which probably should not have been built on, are vulnerable and this includes all countries. Even coastal areas like Alaska that were once protected by sea ice now have open waters and coastal erosion,” Trenberth said.

A lot of storms, worsened by sea level rise, have also occurred in New Zealand.

Trenberth noted Storm Gabrielle which hit New Zealand in February and caused “tremendous damage.”

Sebesvari said that small island nations in the Pacific, Indian and Atlantic Oceans are also “among the most vulnerable to sea level rise.”

“These nations have limited land area and are often located just a few meters above sea level, which means that even a small rise in sea level could have catastrophic consequences. Freshwater sources could be salinized and flooding could occur more frequently and with more devastating impacts. An example are the Maldives, which is an archipelago of low-lying islands, with the highest point being just few meters above sea level,” Sebesvari said.

“As sea levels rise, the islands are at risk of experiencing heavy floods and could even be partly submerged. Pacific Island nations, such as Kiribati, Tuvalu and the Marshall Islands, are low-lying and face the same risks as well. Sea level rise could displace inhabitants, harm the economies of these nations, and threaten the loss of their unique cultures and traditions.”

The Maldives is the flattest country on the globe. The Union of Concerned Scientists previously predicted that the Maldives will see a 1.5 feet increase in sea levels and as a result, lose 77 percent of its land by the year 2100.

“Overall, rising sea levels pose a significant threat to many countries and areas around the world, with potentially devastating consequences for people and economies,” Sebesvari said.

Can We Stop Rising Sea Levels?

The rise we are seeing in sea levels is certainly alarming—but can anything be done?

“Coastal regions and barrier islands are vulnerable, and many areas now settled are not viable in the longer term. Abandonment is likely in some areas. Others can be protected with sea walls: think the Netherlands; and devices to stop high tides—as in the Thames, or Venice—can help for many decades. But stopping emissions of carbon dioxide is most important,” Trenberth said.

Most countries have ratified the Paris agreement, which aims to keep the rise in mean global temperature to well below 2 degrees Centigrade (3.6 degrees Fahrenheit) above pre-industrial levels.

But even if greenhouse gasses are stopped completely, there is a degree of damage that has already been done.

“Even if we stop the emission of greenhouse gases immediately, we will need to deal with sea level rise for the centuries to come. However, the amount we will deal with is in our hands if we choose to act now,” Sebesvari said.

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