Sea level rise is perhaps the most serious consequence of the current climate crisis.
The ocean is absorbing more than 90 percent of the greenhouse gases that are released into the atmosphere. This is causing the sea water to expand. Also, as the world warms, glaciers and ice sheets melt, feeding the world’s oceans.
The scary thing? All of this is happening at an alarming rate. And scientists fear it could spiral out of control if the effects of climate change are not mitigated immediately.
“It’s better to think about sea level rise sooner or later. Current rates globally are 4 millimeters/year, which in a century is 40 centimeters, or about 16 inches. But in general, it’s expected It goes up and we could get to about 2 feet by 2100, but sooner or later we’re going to get to 2 feet or more,” said Kevin Trenberth, a distinguished scholar at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado. news week.
“Even if we stop global warming by reducing emissions to net zero, sea levels will continue to rise for centuries.”

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Even a small rise in sea level has the potential to devastate certain regions. This means that if no action is taken, the world could look very different in just a few decades.
In fact, the effects of sea level rise have already been seen. Sea level rise can contribute to more devastating storm surges during powerful hurricanes and typhoons, many of which we have seen in coastal regions.
So where can we expect to see these drastic changes, and which countries are most at risk?
Which 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 rising sea levels are low-lying coastal regions and small island nations,” Zita Sebesvari, a senior scientist at the United Nations University Institute for Environment and Human Security. (UNU-EHS), said news week.
This includes areas along the eastern and Gulf coasts of the US Scientists have predicted that sea levels along the US coast could rise by as much as one foot by 2050.
A study published in the journal nature communications in April 2023, found that the rate of sea level rise along these coasts “is unprecedented in at least 120 years.” Flooding is expected to worsen dramatically in 2050 as sea levels continue 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 of 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 cities most at risk include New York City, Jakarta, Tokyo, Shanghai and Mumbai”.
Jakarta was dubbed the “fastest sinking city” in the world according to a 2018 BBC report. The World Economic Forum predicted in 2019 that the city could be underwater by 2050.
The New York City Panel on Climate Change also predicts that water around New York City could rise by 8 to 30 inches by 2050. As one of the world’s most populous 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 and technology on May 2 of this year, found that hundreds of dangerous sites on the California coast, including wastewater treatment plants and oil and gas facilities, will flood more frequently as sea levels rise. With the increasing number of storms being seen as the climate crisis worsens, this could cause hazardous chemicals from these facilities to leak into the environment.
The effects of sea level rise have already begun to manifest from an increase in storm surges. One example was Storm Sandy, a devastating tropical hurricane that struck New York City on October 29, 2012. The storm caused storm surge in the East River, which subsequently caused flooding reaching up to 14 feet in some areas.
Hurricane Ian also revealed problems in Florida, Trenberth said.
“More broadly, low-lying areas that were once considered great places but probably shouldn’t have been built on are vulnerable, and this includes every country. Even coastal areas like Alaska that were once protected by ice marine, now you have open water and coastal erosion,” Trenberth said.
Many storms, made worse by rising sea levels, have also occurred in New Zealand.
Trenberth noted that Storm Gabrielle hit New Zealand in February and caused “tremendous damage.”
Sebesvari said 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 only a few meters above sea level, which means that even a small rise in sea level could have catastrophic consequences. Freshwater sources could become salinized. and flooding could occur more frequently and with more devastating impacts.An example is the Maldives, which is an archipelago of low-lying islands, with the highest point just a few meters above sea level,” Sebesvari said.
“As sea levels rise, the islands are at risk of severe flooding and could even be partially submerged. Pacific island nations such as Kiribati, Tuvalu and the Marshall Islands are low lying and also face the same risks. Sea levels could displace people, damage the economies of these nations, and threaten the loss of their unique cultures and traditions.”
The Maldives is the flattest country in the world. The Union of Concerned Scientists previously predicted that the Maldives will see a 1.5-foot rise in sea level and lose 77 percent of its land as a result by the year 2100.
“Overall, sea level rise poses a significant threat to many countries and areas of the world, with potentially devastating consequences for people and economies,” Sebesvari said.
Can we stop sea level rise?
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 now populated areas are not viable in the long term. Some areas are likely to be abandoned. Others can be protected with sea dikes – think the Netherlands; and devices to stop the high tides, like in the Thames or Venice can help for many decades. But stopping carbon dioxide emissions is the most important thing,” Trenberth said.
Most countries have ratified the Paris agreement, which aims to keep the increase in average global temperature well below 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels.
But even if the greenhouse gases stop altogether, there is a degree of damage that has already been done.
“Even if we stop the emission of greenhouse gases immediately, we will have to deal with rising sea levels for centuries to come. However, how much we will deal with is in our hands if we decide to act now,” Sebesvari said. .
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