Recent climate assessments indicate that the year 2025 is now recorded as the fifth warmest year in the western Pacific, reflecting a persistent warming trend that is dramatically changing environmental conditions throughout the region. The ERA5 dataset from the Copernicus Climate Change Service revealed that 2025 ranks as the third warmest year globally, following the exceptionally high temperatures noted in both 2024 and 2023.
In the western Pacific, temperatures averaged 0.65 °C above the baseline set between 1961 and 1990. This area has seen a steady increase in temperatures at an approximate rate of 0.1 °C per decade since 1940. Significantly, every year since 1986 has exceeded the long-term average, with all five of the hottest years documented occurring after 2016.
The report highlighted especially warm conditions over the western equatorial Pacific and the Coral Sea, which includes areas near Papua New Guinea and New Caledonia. This rise in temperatures is likely linked to unprecedented increases in sea surface temperatures in those areas. Interestingly, while cooler air temperatures were observed in the central tropical Pacific due to neutral ENSO or La Niña patterns, the readings for daytime and nighttime temperatures in 2025 nonetheless soared above average, by 0.68 °C and 0.63 °C respectively, marking some of the highest records on file.
The continuous climb in air temperatures across the Pacific underscores the critical importance of consistent monitoring. Although regional temperature variances may diverge from global trends, even slight increases can result in significant repercussions regarding public health, food security, ecosystems, and the everyday lives of Pacific communities.
Salesa Nihmei, Director of the Climate Science and Information Programme at the Secretariat of the Pacific Regional Environment Programme (SPREP), asserted that the evidence on climate change within the Pacific is irrefutable. The Pacific Regional Climate Centre Network, alongside initiatives like the Climate and Oceans Support Program in the Pacific (COSPPac), is committed to converting regional climate data into actionable strategies, enabling Pacific nations to anticipate challenges and implement proactive measures to protect lives and livelihoods.
The Climate and Ocean Support Programme in the Pacific, financed by Australia and New Zealand, is completing its third phase, focusing on providing practical and usable information. This initiative is essential for guiding government planning and facilitating discussions on international climate negotiations.
As the Pacific region grapples with increasing temperatures, the demand for reliable climate data and ongoing collaboration becomes vital in enhancing community resilience and adapting to the effects of climate change. Climate initiatives are setting a hopeful path forward, symbolizing the potential for collective action to address environmental challenges.