Sea Level Rise: A Global Crisis in Motion
Sea level rise is one of the most pressing consequences of climate change, with the potential to impact millions of lives by 2100. As global temperatures increase and ice sheets melt, the sea level is rising at an alarming rate, already climbing by over 10 centimeters in the last decade alone. The United Nations (UN) has warned that by the end of this century, over 410 million people may be at risk from coastal flooding, threatening homes, livelihoods, and entire communities.
Measuring Sea Level Rise
For over a century, scientists have been tracking sea level changes. Initially, tide gauges, attached to piers and other coastal structures, were used to monitor the sea's surface. In more recent times, satellite technology has taken over, offering a more comprehensive global view. By bouncing radar signals off the ocean’s surface, satellites provide precise measurements of sea level fluctuations across the globe. This data is then averaged to account for the varying local weather conditions that might skew short-term readings.
According to NASA, global sea levels have risen by more than 10 cm between 1993 and 2024. These seemingly small increases are actually profound, particularly during storms when higher sea levels allow storm surges to reach further inland, causing more extensive damage.
The Causes of Rising Seas
The primary drivers of sea level rise are well-established. First, the melting of glaciers and ice sheets contributes vast quantities of water to the ocean. Second, as ocean temperatures increase, seawater expands, exacerbating the rise.
The Greenland and Antarctic ice sheets, in particular, are contributing significantly to this issue. Greenland alone is losing around 30 million tonnes of ice per hour, pushing global sea levels upward. Scientists have found that the Greenland ice sheet is on the brink of irreversible collapse, a development that could occur as early as 2025. Combined with the melting of the Thwaites Glacier in Antarctica, often called the "doomsday glacier," sea levels could rise by more than three meters if these critical ice masses collapse.
Adding to the problem is the ocean’s absorption of heat caused by increased greenhouse gas emissions. Since 1971, the oceans have absorbed over 90% of the excess heat in the Earth’s climate system, further accelerating the rate of sea level rise.
Countries at Greatest Risk
Rising sea levels do not affect all regions equally. Some countries are far more vulnerable than others. Bangladesh, China, India, and the Netherlands have been identified as particularly at risk, with nearly 900 million people living in low-lying coastal regions that face acute danger.
In the Pacific, small island nations such as Kiribati, Tuvalu, and the Marshall Islands are also facing existential threats. These nations are not only exposed to rising seas but also to tropical storms and cyclones, which are becoming more frequent and severe due to climate change.
In Europe, projections indicate that sea levels could rise by more than 10 cm before 2050, and in the U.S., almost 1,100 critical buildings in coastal communities could face monthly flooding by mid-century. In many areas, communities may become uninhabitable within the next few decades.
Adaptation Efforts and Challenges
In response to these challenges, countries around the world are taking steps to adapt. New Zealand is developing climate adaptation policies to prevent new public housing projects from being built in areas prone to climate hazards. Coastal defences such as sea walls and surge barriers are being strengthened in Denmark, Germany, and the United Kingdom. In South Korea and the Maldives, experiments with floating homes offer an innovative solution for communities facing the immediate threat of rising seas.
However, adaptation efforts are falling short, particularly in terms of funding. The current finance gap for adaptation is estimated between $194 billion and $366 billion annually, leaving many vulnerable communities without the resources needed to protect themselves from the worst effects of sea level rise.
Fiji is already experiencing the human cost of sea level rise, with plans to relocate entire villages to higher ground. Six villages have already been moved, and 42 more have been identified for relocation in the next five to ten years.
International Dialogue on Sea Level Rise
Sea level rise has become a central issue on the world stage, with the UN General Assembly (UNGA) holding a High-Level Meeting on the topic in September 2024. The meeting will address the legal, financial, socio-economic, and scientific aspects of sea-level rise, with the goal of developing comprehensive strategies to mitigate its impacts.
Simultaneously, the World Economic Forum’s Sustainable Development Impact Meetings (SDIM24) will focus on issues related to climate change, energy transition, and nature preservation. With only 17% of the UN’s Sustainable Development Goals (SDGs) on track, these discussions underscore the urgent need for coordinated global action to address rising seas and other critical climate challenges.
Conclusion
Sea level rise is not a distant threat; it is a current reality that is already reshaping coastlines and endangering communities worldwide. While efforts to adapt are underway, much more must be done to close the funding gap, improve infrastructure, and protect vulnerable populations. As the global community continues to address this crisis, it is clear that only through coordinated, sustained efforts can we hope to mitigate the devastating impacts of rising seas.
