Latest news with #IntegratedEarthSystemObservatory
Zawya
02-04-2025
- Science
- Zawya
Unexpected sea level rise threatens coastal ecosystems and marine biodiversity
Sea level rise is a major global issue driven by climate change, primarily due to melting ice caps and the thermal expansion of seawater. Higher sea levels lead to more frequent and severe coastal flooding. Increased erosion have seen threatening coastal infrastructure and communities around the world. Globally, sea level rose faster than expected in 2024, mostly because of ocean water expanding as it warms, or thermal expansion. According to a recent Nasa-led analysis, last year's rate of rise was 0.23 inches (0.59 centimetres) per year, compared to the expected rate of 0.17 inches (0.43 centimetres) per year. 'The rise we saw in 2024 was higher than we expected,' said Josh Willis, a sea level researcher at Nasa's Jet Propulsion Laboratory in Southern California. 'Every year is a little bit different, but what's clear is that the ocean continues to rise, and the rate of rise is getting faster and faster.' In recent years, about two-thirds of sea level 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 of seawater. But in 2024, those contributions flipped, with two-thirds of sea level rise coming from thermal expansion. 'With 2024 as the warmest year on record, Earth's expanding oceans are following suit, reaching their highest levels in three decades,' said Nadya Vinogradova Shiffer, head of physical oceanography programmes and the Integrated Earth System Observatory at Nasa Headquarters in Washington. Since the satellite record of ocean height began in 1993, the rate of annual sea level rise has more than doubled. In total, global sea level has gone up by 4 inches (10 centimetres) since 1993, noted Jane J Lee of Nasa's Jet Propulsion Laboratory. According to Nasa, 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. 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. The massive movement of water during El Niño — in which a large pool of warm water normally located in the western Pacific Ocean sloshes over to the central and eastern Pacific — can also result in vertical movement of heat within the ocean. In another report, Nasa noted the rate of global sea level rise doubled in the last 30 years. Citing recent findings, the premier space agency said this rate measures the average rise in sea level each year — most of it resulting from climate change. The study found that in 1993, the rate was about 0.08 inches (2.1 millimetres) per year but has since increased to about 0.18 inches (4.5 millimetres) per year in 2023. The study reports that sea level also is expected to grow by another 6.6 inches (169 millimetres) globally over the next 30 years if it follows this trend. 'We have had this succession of satellite missions over the past three decades, one building on top of another, and it's that data on a global scale that allows us to precisely track the rate of global sea level rise,' said Nasa Sea Level Change Team Principal Investigator Benjamin Hamlington, the new study's lead author. Although a number of factors contribute to sea level rise, the primary causes are warming and ice-melt due to greenhouse gas emissions, Hamlington said. © Gulf Times Newspaper 2022 Provided by SyndiGate Media Inc. (
Yahoo
14-03-2025
- Science
- Yahoo
Global sea level rose faster than expected in 2024, according to NASA analysis
Climate change was a major driver to an unexpected level of sea level rise in 2024, according to a new NASA analysis. Global sea levels rose 0.23 inches in 2024, satellite records show, compared to the predicted 0.17 inches expected for the year. MORE: Coastal US cities are sinking as sea levels continue to rise, new research shows "The rise we saw in 2024 was higher than we expected," said Josh Willis, a sea level researcher at NASA's Jet Propulsion Laboratory, in a statement. "Every year is a little bit different, but what's clear is that the ocean continues to rise, and the rate of rise is getting faster and faster." The majority of the difference between predicted and actual sea level rise was attributed to thermal expansion -- or the ocean waters expanding as they warm, researchers said. An unusual amount of ocean warming, combined with meltwater from land-based ice such as glaciers, led to the increase of sea level rise last year, according to NASA. MORE: How rising sea levels will affect New York City, America's most populous city About two-thirds of sea level rise in recent years has resulted from the melting of ice sheets and glaciers, with a third coming from thermal expansion, according to NASA. In 2024, those metrics flipped, with two-thirds of the rise attributed to expanding ocean water and one-third attributed to contributions from melting ice. "With 2024 as the warmest year on record, Earth's expanding oceans are following suit, reaching their highest levels in three decades," said Nadya Vinogradova Shiffer, head of physical oceanography programs and the Integrated Earth System Observatory at NASA. The rate of annual sea level rise has more than doubled since the satellite record began in 1993 -- with sea levels rising at least 4 inches since then, according to NASA. MORE: How climate change, rising sea levels are transforming coastlines around the world Sea levels have risen between 8 inches and 9 inches since 1880, according to the National Oceanic and Atmospheric Administration. Human-amplified climate change is the primary cause for present-day rising sea levels, climate research shows. Heat from the ocean's surface has slowly making its way down into cooler waters deeper into the sea, according to NASA. The massive movement of water during El Niño can also result in vertical movement of heat throughout the ocean's layers. Global sea level rose faster than expected in 2024, according to NASA analysis originally appeared on
Al Jazeera
14-03-2025
- Science
- Al Jazeera
‘Unexpected' rate of sea level rise in 2024: NASA
Sea levels rose faster than expected around the world in 2024 – the Earth's hottest year on record, according to new findings from the United States' NASA space agency, which attributed the rise to warming oceans and melting glaciers. 'With 2024 as the warmest year on record, Earth's expanding oceans are following suit, reaching their highest levels in three decades,' NASA's Nadya Vinogradova Shiffer, head of physical oceanography programmes and the Integrated Earth System Observatory, said on Thursday. Josh Willis, a sea level researcher at NASA, said the rise in the world's oceans last year was 'higher than expected', and while changes take place each year, what has become clear is that the 'rate of rise is getting faster and faster'. According to the NASA-led study of the information sourced via the Sentinel-6 Michael Freilich satellite, the rate of sea level rise last year was 0.59cm (0.23 inches) per year – higher than an initial expected estimate of 0.43cm (0.17 inches) per year. Satellite recordings of ocean height started in 1993, and in the three decades up to 2023, the rate of sea level rise has more than doubled, with average sea levels around the globe rising by 10cm (3.93 inches) in total, according to NASA. Rising sea levels are among the consequences of human-induced climate change, and oceans have risen in line with the increase in the Earth's average surface temperature – a change which itself is caused by greenhouse gas emissions. NASA said trends from recent years showed additional water from land due to melting ice sheets and glaciers to be the biggest contributor, accounting for two-thirds of sea level rise. In 2024, however, the increased rise in sea levels was largely driven by the thermal expansion of water – when ocean water expands as it warms – which accounts for about two-thirds of the increase. The UN has warned of threats to vast numbers of people living on islands or along coastlines due to rising sea levels, with low-lying coastal areas of India, Bangladesh, China and the Netherlands flagged as areas of particular concern, as well as island nations in the Pacific and Indian Oceans.
