{"id":105944,"date":"2025-03-22T09:15:21","date_gmt":"2025-03-22T08:15:21","guid":{"rendered":"https:\/\/www.sonnenseite.com\/?p=105944"},"modified":"2025-03-22T09:15:22","modified_gmt":"2025-03-22T08:15:22","slug":"nasa-analysis-shows-unexpected-amount-of-sea-level-rise-in-2024","status":"publish","type":"post","link":"https:\/\/www.sonnenseite.com\/en\/science\/nasa-analysis-shows-unexpected-amount-of-sea-level-rise-in-2024\/","title":{"rendered":"NASA Analysis Shows Unexpected Amount of Sea Level Rise in 2024"},"content":{"rendered":"\n

Last year\u2019s increase was due to an unusual amount of ocean warming, combined with meltwater from land-based ice such as glaciers.<\/p>\n\n\n\n

Global sea level rose faster than expected in 2024, mostly because of ocean water expanding as it warms, or thermal expansion. According to a NASA-led analysis, last year\u2019s rate of rise was 0.23 inches (0.59 centimeters) per year, compared to the expected rate of 0.17 inches (0.43 centimeters) per year.<\/p>\n\n\n\n

\u201cThe rise we saw in 2024 was higher than we expected,\u201d said Josh Willis, a sea level researcher at NASA\u2019s Jet Propulsion Laboratory in Southern California. \u201cEvery year is a little bit different, but what\u2019s clear is that the ocean continues to rise, and the rate of rise is getting faster and faster.\u201d<\/p>\n\n\n

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This graph shows global mean sea level (in blue) since 1993 as measured by a series of five satellites. The solid red line indicates the trajectory of this increase, which has more than doubled over the past three decades. The dotted red line projects future sea level rise. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n<\/div>\n\n\n

In recent years, about two-thirds of sea level<\/a> rise was from the addition of water from land into the ocean by melting ice sheets and glaciers. About a third came from thermal expansion<\/a> of seawater. But in 2024, those contributions flipped, with two-thirds of sea level rise coming from thermal expansion.<\/p>\n\n\n\n

\u201cWith 2024 as the warmest year on record, Earth\u2019s expanding oceans are following suit, reaching their highest levels in three decades,\u201d said Nadya Vinogradova Shiffer, head of physical oceanography programs and the Integrated Earth System Observatory at NASA Headquarters in Washington.<\/p>\n\n\n

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This picture shows the rise in global mean sea level from 1993 to 2024 based on data from five international satellites. The expansion of water as it warms was responsible for the majority of the higher-than-expected rate of rise in 2024. Credit: NASA\u2019s Scientific Visualization Studio<\/figcaption><\/figure>\n<\/div>\n\n\n

Since the satellite record of ocean height began in 1993, the rate of annual sea level rise<\/a> has more than doubled. In total, global sea level has gone up by 4 inches (10 centimeters) since 1993.<\/p>\n\n\n\n

This long-term record is made possible by an uninterrupted series of ocean-observing satellites starting with TOPEX\/Poseidon<\/a> in 1992. The current ocean-observing satellite in that series, Sentinel-6 Michael Freilich<\/a>, launched in 2020 and is one of an identical pair of spacecraft that will carry this sea level dataset into its fourth decade. Its twin, the upcoming Sentinel-6B satellite<\/a>, will continue to measure sea surface height down to a few centimeters for about 90% of the world\u2019s oceans.<\/p>\n\n\n\n

Mixing It Up<\/h4>\n\n\n\n

There are several ways in which heat makes its way into the ocean, resulting in the thermal expansion of water. Normally, seawater arranges itself into layers determined by water temperature and density. Warmer water floats on top of and is lighter than cooler water, which is denser. In most places, heat from the surface moves very slowly through these layers down into the deep ocean.<\/p>\n\n\n\n

But extremely windy areas of the ocean can agitate the layers enough to result in vertical mixing. Very large currents, like those found in the Southern Ocean, can tilt ocean layers, allowing surface waters to more easily slip down deep.<\/p>\n\n\n\n

The massive movement of water during El Ni\u00f1o \u2014 in which a large pool of warm water normally located in the western Pacific Ocean sloshes over to the central and eastern Pacific \u2014 can also result in vertical movement of heat within the ocean.<\/p>\n\n\n\n