Climate Justice: Existential Threats to Lowlands and Small Island Nations

Climate change is no longer a distant threat-it is a present-day reality reshaping the lives of millions living on lowlands and small island nations. For communities situated just metres above sea level, rising temperatures, intensifying storms, and creeping seas present nothing less than an existential crisis. These regions, despite contributing minimally to global greenhouse gas emissions, bear the brunt of climate consequences. Understanding the vulnerabilities of lowlands and small islands is essential for grasping the full scope of climate justice.

What are lowlands and why do they matter? 🔗

Lowlands refer to broad expanses of land with generally low elevation. They encompass a variety of landscapes including coastal plains, river deltas, floodplains, depressions in mountain interiors, and regions contrasting with highland areas. These territories are found on every continent and serve as critical zones for agriculture, settlement, and economic activity.

Coastal lowlands are particularly significant because they often host dense populations and vital infrastructure. Rising high-tide flooding events combined with extreme rainfall and storm surge are increasing the frequency and magnitude of flood events in these areas. Many older coastal cities were built just above sea level and rely on gravity-driven drainage systems that are now overwhelmed by rising waters.

Lowland regions also include some of the world’s most productive agricultural zones. River deltas like the Ganges-Brahmaputra and Mekong support hundreds of millions of people dependent on rice cultivation and fishing. These areas face compounding threats from flooding, saltwater intrusion, and soil erosion-all worsened by climate change.

Agricultural impacts in lowland regions 🔗

Farming communities in lowlands face severe disruptions from climate variability. Floods and extreme rainfall substantially lower agricultural income and increase household food insecurity in affected regions. When fields become submerged, oxygen in the root zone depletes rapidly, disrupting water uptake and nutrient transport in plants.

The economic toll is staggering. Rapid temperature changes and increasing floods slash agricultural yields in small islands and lowlands, reducing their ability to produce food locally. Rising sea levels cause saltwater encroachment that threatens coastal farmland and freshwater supplies. In Bangladesh, both pre-monsoon and monsoon floods routinely damage crops in northern lowland areas, directly impacting farm income and food security.

Coastal flooding poses additional long-term challenges through soil salinisation. When saltwater inundates farmland, the damage persists for years as salts remain in the soil profile. Financial losses from a single coastal flood event can range significantly higher than freshwater flooding due to these extended salt damage projections.

Flooding and infrastructure vulnerability 🔗

Storm surge is an abnormal water level rise generated by storms that can cause extreme flooding in coastal areas, particularly when it coincides with high tide. Water levels can reach six metres or more above normal in some cases. The destructive power of surge combines with battering waves to demolish structures not specifically designed to withstand such forces.

Saltwater intrusion from storm surge endangers public health, kills vegetation, and contaminates freshwater sources. Storm surges occurring today are approximately 20 centimetres higher than they would have been in 1900 due to global sea level rise. For communities in low-lying coastal plains, this means that previously survivable storms now cause catastrophic flooding.

Small Island Developing States: characteristics and challenges 🔗

The 39 Small Island Developing States are remote economies prone to natural disasters and highly affected by climate change. They face challenges including high import and export costs while relying heavily on external markets due to narrow resource bases. Since they control an ocean area averaging 28 times their land mass, most natural resources come from surrounding seas.

SIDS share several common characteristics despite their diversity. These include small physical size, limited natural resources, oceanic boundaries, sensitivity to external shocks, high population density, and often limited infrastructure. The average population density in SIDS is 361 people per square kilometre-more than six times the global average-making them even more vulnerable to extreme weather impacts.

The three geographical regions containing SIDS are the Caribbean, the Pacific, and the Atlantic, Indian Ocean, and South China Sea (AIS). These nations are responsible for less than one percent of global greenhouse gas emissions but are among the most affected by climate change impacts. Their total land area is less than 0.5 percent of the world’s surface, yet they host over 20 percent of global biodiversity and 40 percent of the world’s coral reefs.

Economic and social vulnerabilities 🔗

From 1970 to 2020, SIDS lost US$153 billion due to weather extremes-a significant amount relative to their average GDP of US$13.7 billion. Industries like tourism and fisheries can constitute up to half the GDP of some small island economies, making them highly susceptible to climate disruptions.

Tropical Cyclone Dorian in 2019 resulted in over US$3 billion in damages and losses in the Bahamas alone, with 30,000 people impacted. Tropical Cyclone Maria hit Dominica in 2017 and caused economic damage equivalent to 226 percent of the country’s GDP, affecting 80 percent of the population. These events demonstrate how a single storm can devastate an entire national economy.

Tourism contributes an average of 30 percent to SIDS economies, making the sector’s vulnerability to extreme weather a national economic concern. When COVID-19 struck in 2020, tourist arrivals declined by 67 percent in the Caribbean and 70 percent in the Pacific, revealing how external shocks can compound climate vulnerabilities.

Sea level rise: the existential threat 🔗

For small island nations, sea level rise presents the most fundamental challenge to their existence. Sea level in coastal areas is projected to rise 20 centimetres or more by 2050 and potentially another 50 to 100 centimetres by century’s end. This poses direct challenges for low-lying islands where much of the land area and critical infrastructure sits within 500 metres of the coast.

Four low-lying atoll nations face the greatest risk: Marshall Islands with a highest point of 10 metres, Maldives at 5.1 metres, Tuvalu at 4.6 metres, and Kiribati. For Tuvalu, the situation is particularly dire-95 percent of the country could be underwater during high tide by 2100 if current trends continue.

Sea level in Tuvalu is already nearly 15 centimetres higher than it was 30 years ago, rising at approximately five millimetres per year-1.5 times faster than the global average. Much of the country’s land area and infrastructure will be below average high tide by 2050. Scientists project that by then, 50 percent of the capital Funafuti will experience tidal flooding.

Cascading impacts on communities 🔗

The rising saltwater table threatens deep-rooted food crops like coconut, pulaka, and taro before actual flooding occurs. Sea water has infiltrated island soil and made it difficult to grow staples of the Tuvaluan diet. Freshwater supplies are becoming contaminated, and coral reef degradation threatens both food sources and natural storm protection.

The loss of nations like Tuvalu would not only displace populations but also eradicate unique cultural heritage and history. For island communities, the word for land often encompasses both physical territory and a sense of belonging rooted in identity. Migration represents not just a physical relocation but a potential loss of nationhood itself.

Climate change is projected to amplify present direct economic damages from coastal flooding by more than 14 times under high-emission scenarios by century’s end. Even limiting global warming to 1.5°C would not prevent several SIDS from suffering economic losses corresponding to considerable shares of their GDP, likely leading to forced migration from coastal zones.

The fight for climate justice and survival 🔗

Climate change is an existential threat to small islands, which are extremely vulnerable to sea level rise and extreme weather events like tropical storms, hurricanes, droughts, and cyclones that can decimate communities and infrastructure. These crises have become more intense and interconnected, with climate-related disasters nearly doubling over the past 20 years.

SIDS have been at the forefront of international climate advocacy. Tuvalu’s permanent secretary for foreign affairs has stated that sea level rise should be treated as a standalone agenda, calling it an existential threat to the country’s statehood and survival of its identity. The nation is working to maintain sovereignty and maritime boundaries even if physical land becomes uninhabitable.

Innovative responses are emerging. Australia and Tuvalu signed the Falepili Union treaty in 2023, which provides funding for coastal restoration projects and allows Tuvaluans to emigrate to Australia annually. Tuvalu’s Coastal Adaptation Project aims to create new land above high tides and storm surges, potentially expanding the capital by 3.6 square kilometres at elevations safe from seawater for over 80 years.

Global responsibility and action needed 🔗

Keeping global warming below 1.5°C could avoid almost half of unmitigated damage to SIDS, depending on the region. However, substantial adaptation efforts will still be required. To keep economic damages in 2100 at today’s levels, existing protection would need to be upgraded to withstand sea level rises exceeding one metre in several countries.

The annual cost of adapting to climate change in SIDS is estimated between US$22 billion and US$26 billion per year, roughly four to five percent of their combined GDP. This underscores the urgent need for international support, particularly given that these nations contributed minimally to causing the climate crisis.

The situation of lowlands and small islands illuminates a fundamental climate justice issue: those least responsible for climate change suffer its worst consequences. As rising seas threaten to redraw the world map, the international community faces a moral imperative to act decisively. The survival of entire nations and the displacement of millions of people hang in the balance.

What do you think? How should the global community balance responsibility between nations that have contributed most to climate change and those suffering its greatest impacts? What rights should climate-displaced populations have when their homeland becomes uninhabitable?

References

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