Study: Sea surface is rising at the fastest rate in 4,000 years Environment and climate

A new study warns that sea levels are rising faster than at any time in the past 4,000 years, indicating the urgent need to take global and local action to reduce global warming and avert major disasters.

Scientists at Rutgers University examined thousands of geological records from multiple sources, including ancient coral reefs and mangroves, which are often used as a “natural archive” of past sea levels.

Scientists reconstructed changes in sea level dating back approximately 12,000 years to the beginning of the Holocene, the current geological era that began about 11,700 years ago after the end of the last major ice age.

The results, published in the journal Nature, showed that global sea levels have risen since 1900 at an average rate of 1.5 millimeters per year.

The study noted that sea level rise is a global issue, but China faces a “double threat” as its largest and most economically important cities are particularly vulnerable to submergence.

The study highlights “two major forces” accelerating sea level rise: thermal expansion and melting glaciers.

As the planet warms due to climate change, the oceans absorb more heat and expand. Meanwhile, ice sheets in polar regions are melting at unprecedented rates, adding more water to the oceans.

The study indicates that rising temperatures cause the ocean to accommodate a larger volume, and glaciers respond faster because they are smaller than ice sheets that are often the size of continents, confirming an increasing acceleration of melting in Greenland.

The Greenland ice sheet lost 80 billion tons of ice over the 12 months from September 2023 to August 2024, marking the 28th consecutive year in which it lost more ice than it produced.

The Greenland ice sheet, currently one of the world’s largest freshwater resources, contains water that would cause global sea levels to rise by the equivalent of 7.4 metres.

Sea level rise is a symptom of climate change, and with every centimeter of sea level rise, about 6 million people on the planet are exposed to coastal flooding.

And it showed Previous study The slightest expected increase in temperatures, even with reduced emissions, could lead to about 3 million buildings being regularly flooded. A sea level rise of 5 meters or more could put more than 100 million buildings at risk over the coming centuries, including residential neighborhoods and entire vital infrastructure.

Sea level rise leads to worsening storms, with rising water levels along coastlines, and an increased frequency of high-tide floods, which are sometimes called “nuisance floods,” because they are not generally fatal or dangerous, but they can be devastating and costly.

Saltwater intrusion caused by sea level rise also pollutes land and freshwater resources, destroys crops and livelihoods, damages infrastructure and the livelihoods of coastal communities, and undermines agriculture.