Terrifying Video Shows Sea Level Rise Predictions Were True

Rising sea levels may seem like a problem for the future, but it's already been happening for decades, a NASA animation shows.

The graphic, made by Andrew J. Christensen, a data visualizer for the NASA Scientific Visualization Studio, shows how much the sea level has risen in the 30 years between 1993 and 2022.

Since 1993, sea levels across the world have risen by about 3.9 inches, as shown in the video from the perspective of a ship window with water rising over it.

In the 1990 report of the Intergovernmental Panel on Climate Change (IPCC), sea levels were predicted to rise by between 2 mm (0.08 inches) and 7.3 mm (0.29 inches) per year up until 2030, accelerating to between 3.3 mm (0.2 inches) and 10.5 mm (0.41) per year until 2060.

The early predictions were correct, it seems, as on average, the sea level's 3.9-inch rise over 30 years comes to about 0.13 inches per year. The rise in sea levels is also accelerating, with levels expected by the the U.S. National Climate Assessment to have risen about 2 to 6 feet by 2100.

"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, previously told Newsweek.

Sea levels are rising as a result of human-driven climate change's impact on the planet, warming of the ocean, and increased melting of glaciers and ice sheets. Melting glaciers add water to the oceans, while increased ocean temperatures cause the water to expand, taking up more volume, according to the National Oceanic and Atmospheric Administration (NOAA).

The ocean absorbs 90 percent of the increased atmospheric heat associated with emissions from human activity.

The rising sea levels are bad news for people living near the coast, which in the United States amounts to nearly 40 percent of the population. The population centers are at risk of increased flooding, shoreline erosion and hazards from storms

"Sea level rise poses a significant threat to low-lying coastal areas and coastal communities," Zita Sebesvari, senior scientist at the United Nations University—Institute for Environment and Human Security (UNU-EHS), told Newsweek in May. "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."

Some areas along U.S. East and Gulf coasts could see sea levels rise by up to a foot by 2050, with one study published in the journal Nature Communications in April 2023 showing that the sea level rise rate along these coasts is "unprecedented in at least 120 years."

"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," Sebesvari said.

The NYC Panel on Climate Change predicted that New York City could see a water level increase of between 8 and 30 inches by 2050. NASA's interactive maps show just how much of the world's coastlines might be underwater as a result of a sea level rise.

The increasing sea levels are also expected to be exacerbated by other side effects of climate change, including more powerful and frequent tropical storms like hurricanes, that may result in increased storm damage across the worst affected areas.

"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.

The sea level is expected to rise about 7.5 feet for each degree Celsius of temperature rise, or for ever 1.8 degree Fahrenheit. We could slow the rise by drastically cutting carbon emissions, but it seems that the train of sea level rise has already left the station.

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

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