Recent studies published in the scientific journal ‘Scientific Reports’ have predicted global damage, affecting a large population and economic assets as a consequence of rising sea levels (SLR). Worsening climate change has been identified as the main culprit behind this potential crisis.
The Consequences of Sea Level Rise (SLR)
SLR is a direct outcome of climate change and is predicted to increase coastal flooding by 2100. The research suggests that the global population potentially exposed to episodic coastal flooding will rise from 128-171 million people to 176-287 million by 2100. Approximately 0.5-0.7% of the world’s land area is at risk of episodic coastal flooding by 2100, which would impact 2.5-4.1% of the total human population. Furthermore, the value of global assets exposed to such coastal flooding could fall between USD 6,000-9,000 billion or 12-20% of the global GDP.
Understanding Sea Level Rise (SLR)
The rise in sea levels is directly related to climate change factors, specifically global warming, which is caused by three primary factors:
1. Thermal Expansion: As water heats up, it expands. This has accounted for about half of the sea-level rise over the past 25 years, simply due to warmer oceans occupying more space.
2. Melting Glaciers: Increased global temperatures lead to greater-than-average summer melting of large ice formations like mountain glaciers, resulting in an imbalance between runoff and ocean evaporation, leading to further sea level rise.
3. Loss of Greenland and Antarctica’s ice sheets: Similar to mountain glaciers, increased heat causes the huge ice sheets covering Greenland and Antarctica to melt and move into the sea faster.
The average global sea level has risen 8.9 inches between 1880 and 2015, an acceleration compared to the previous 2,700 years.
Regional Variations in SLR
It’s important to note that SLR isn’t uniform worldwide due to factors like subsidence, upstream flood control, erosion, regional ocean currents, variations in land height, and the weight of Ice Age glaciers. Sea levels are mainly measured using tide stations and satellite laser altimeters.
The Impact of Rising Sea Levels
The implications of SLR aren’t just physical. They extend to socio-economic effects as well, such as:
1. Coastal Flooding: Eight out of the world’s ten largest cities are coastal, threatened by increasing coastal flooding.
2. Destruction of Coastal Biodiversity: Rising sea levels can cause destructive erosion, wetland flooding, soil and groundwater contamination, and loss of habitat for biodiversity.
3. Lateral and Inland Migration: Increased flooding is forcing people to move to higher ground, causing displacement and sparking refugee crises worldwide.
4. Effect on Communications Infrastructure: Internet access, a basic service, could be disrupted by higher coastal water levels.
Other potential impacts include damage to tourism in coastal areas and military preparedness.
Adapting to Rising Sea Levels
Several strategies have been proposed to mitigate the impacts of rising sea levels:
1. Relocation: Many coastal cities are considering relocation. For example, the entirety of Kiribati Island is set to move to Fiji, and the capital of Indonesia is being relocated from Jakarta to Borneo.
2. Building Sea Walls: Projects like Indonesia’s ‘Giant Sea Wall/Giant Garuda’ aim to protect cities from flooding.
3. Building Enclosures: Proposals have been made to construct protective dams around regions most at risk from rising seas.
The Way Forward
Long-term solutions for curtailing SLR lie in reducing greenhouse gas emissions. Steps towards this goal include switching to clean energy sources like solar and wind, instituting carbon taxes and subsidies for reducing the carbon footprint, and implementing carbon sequestration techniques. Afforestation, reducing deforestation, and subsidizing climate change research are also crucial aspects of mitigating this pressing issue.