El Niño Causes Global Sea Level To Spike, NASA Says

Experts said that the El Niño phenomenon has resulted in the rise of global sea level. According to NASA, the global average sea level rose by about 0.3 inches (0.76 centimeters) from 2022 to 2023, which was a relatively large jump due mostly to a warming climate and the development of the strong El Niño.

Global Sea Level Rise

Officials said that the total rise was equivalent to draining a quarter of Lake Superior into the ocean over the course of a year.

The recent analysis was based on a sea level dataset featuring more than 30 years of satellite observations, starting with the U.S.-French TOPEX/Poseidon mission that was launched in 1992.

Scientists said that the Sentinel-6 Michael Freilich mission, which was launched in November 2020, was the latest in the series of satellites that have contributed to this sea level record.

The data showed that global average sea level has risen a total of about 4 inches (9.4 centimeters) since 1993.

The rate of this increase has also accelerated, more than doubling from 0.07 inches (0.18 centimeters) per year in 1993 to the current rate of 0.17 inches (0.42 centimeters) per year.

Experts said that the current rates of acceleration mean that the world is on track to add another 20 centimeters of global mean sea level by 2050.

This will double the amount of change in the next three decades compared to the previous 100 years and it will also increase the frequency and impacts of floods across the world.

Based on the analysis, the global sea level saw a significant jump from 2022 to 2023 due mainly to a switch between La Niña and El Niño conditions.

Experts said that a mild La Niña from 2021 to 2022 resulted in a lower-than-expected rise in sea level that year. Meanwhile, a strong El Niño developed in 2023, helping to boost the average amount of rise in sea surface height.

La Niña is characterized by cooler-than-normal ocean temperatures in the equatorial Pacific Ocean while the El Niño involves warmer-than-average ocean temperatures in the equatorial Pacific.

Climate Phenomena

Experts said that both periodic climate phenomena affect patterns of rainfall and snowfall as well as sea levels around the world.

According to research, the seasonal or periodic climate phenomena can affect global average sea level from year to year.

However, the underlying trend for more than three decades has been increasing ocean heights as a direct response to global warming due to the excessive heat trapped by greenhouse gases in the Earth's atmosphere.

Meanwhile, the researchers also periodically cross-check the sea level measurements against data from other sources. These include tide gauges, as well as satellite measurements of other factors like atmospheric water vapor and Earth's gravity field that can affect the accuracy of sea level measurements.

Using that information, the researchers recalibrated the 30-year dataset, resulting in updates to sea levels in some previous years. That includes a sea level rise increase of 0.08 inches (0.21 centimeters) from 2021 to 2022.

The information dramatically improved the understanding of how sea surface height has been changing on a global scale.

When these sea level measurements are combined with other information, including ocean temperature, ice loss, and land motion, scientists can decipher why and how the sea levels are rising.