Pacific Islands are under severe threat from a combination of rising sea levels, ocean warming, and acidification, according to the World Meteorological Organization’s (WMO) “State of the Climate in the South-West Pacific 2023” report. This alarming report underscores the escalating dangers that climate change poses to the region’s socioeconomic stability and survival.
ACCELERATING CLIMATE IMPACTS
The WMO report reveals that sea level rise in the South-West Pacific is surpassing the global average. Since 1980, sea surface temperatures in the region have increased at a rate three times faster than the global average. Marine heat waves, which have doubled in frequency and intensity, now last longer and affect larger areas.
The report, presented by UN Secretary-General António Guterres and WMO Secretary-General Celeste Saulo at the Pacific Islands Forum in Tonga, was accompanied by a special briefing document titled “Surging Seas in a Warming World.” Guterres described it as “an SOS on sea level rise.”
RISING SEA LEVELS: A GROWING CRISIS
In the western tropical Pacific, sea levels have risen by approximately 10–15 cm (4–6 in), nearly double the global rate since 1993. In the central tropical Pacific, the rise is 5–10 cm (2–4 in). The mean annual sea-level rise from January 1993 to May 2023 is about 4.52 mm per year around the Maritime Continent and 4.13 mm per year around New Zealand, compared to the global average of 3.4 mm per year.
This rise has led to increased coastal flooding. For example:
- Guam: Increased from 2 to 22 times per year
- Penrhyn, Cook Islands: From 5 to 43 times per year
- Majuro, Marshall Islands: From 2 to 20 times per year
- Papeete, French Polynesia: From 5 to 34 times per year
- Pago Pago, American Samoa: From 0 to 102 times per year
SOCIOECONOMIC AND ENVIRONMENTAL IMPACTS
Despite contributing only 0.02% of global emissions, Pacific islands face unique vulnerabilities. With an average elevation of just 1 to 2 meters above sea level and 90% of the population living within 5 kilometres of the coast, these islands are at high risk. The infrastructure, including 50% located within 500 meters of the sea, is also endangered.
Guterres emphasized that while some sea level rise is unavoidable, its extent and impact are influenced by our global actions. He called for drastic cuts in greenhouse gas emissions and increased climate adaptation efforts.
TONGA AND OTHER FRONTLINE NATIONS
Tonga, the host of the 53rd Pacific Islands Forum, faces direct climate hazards including tropical cyclones and flooding. The January 2022 volcanic eruption exacerbated these challenges, injecting massive amounts of water vapour into the atmosphere and affecting global climate patterns.
WMO Secretary-General Celeste Saulo warned: “Climate change is the defining challenge of our time. Communities, economies, and ecosystems in the South-West Pacific are profoundly affected by its cascading impacts.”
OCEAN WARMING AND ACIDIFICATION
From 1981 to 2023, ocean surface temperatures in the South-West Pacific have warmed at a rate more than three times faster than the global average. Marine heat waves have also become more frequent and intense, with significant consequences for fish stocks, coral reefs, and marine ecosystems.
In 2023, notable marine heat waves affected large areas, including New Zealand. The Intergovernmental Panel on Climate Change (IPCC) projects that such events will become more frequent and severe in the future.
Ocean acidification, driven by increased carbon dioxide absorption, has caused a significant decline in ocean chlorophyll and phytoplankton size, impacting the marine food chain.
The WMO report highlights the urgent need for enhanced early warning systems and proactive measures to address these interconnected climate risks. With only one-third of Small Island Developing States having access to such systems, the necessity for global support and action is clear.
