27-04-2025
What Asean, Pacific regions can expect: US National Intelligence Council
Published on: Sunday, April 27, 2025
Published on: Sun, Apr 27, 2025 Text Size: A farmer showing dried up paddy field due to drought in Kota Belud in 2019. (Pic: Bernama) AVERAGE annual temperatures are likely to increase across Southeast Asia and Pacific Islands by approximately 1°C through 2030 and they will keep increasing through the remainder of the 21st century, according to a United States (US) National Intelligence Council (NIC) report published online in 2009. It warned that this region is at risk from the impact of climate change within 20 years until 2030 due to the large growing population, long coastlines, abundant low-lying areas, reliance on the agricultural sector and dependence on natural resources. The Report titled 'Southeast Asia and Pacific Islands: The Impact of Climate Change to 2030' was jointly prepared by Joint Global Change Research Institute, Battelle Memorial Institute, Pacific Northwest Division and Scitor Corporation, and focuses on the nations of Thailand, Cambodia, Laos, Vietnam, the Philippines, Malaysia, Singapore and Indonesia. It said these countries have a diverse range of governments, populations, religions, economic growth, development and allocation of natural resources, but all have a similar tropical maritime climate and face similar threats from climate change. It said the effects of climate change are already being felt in these nations. Average annual surface temperatures in the region increased by 0.5-1.1°C during the period 1901-2005. Precipitation patterns are changing regionally, with increases in some locations and decreases in others. Annual rainfall decreased across most of Indonesia (Java, Lampung, South Sumatra, South Sulawesi and Nusa Tenggara) and increased across most of the northern regions (Kalimantan and North Sulawesi) during 1931-1990. Sea level is rising and the magnitude varies regionally. During 1993-2001, the largest increases in sea level (15-25 mm per year) occurred near Indonesia and the Philippines, while only moderate changes (0-10 mm per year) along the coasts of Thailand, Cambodia, and Vietnam. Climate model simulations indicate average annual temperatures likely to increase by approximately 1°C through 2030, and will keep increasing for the remainder of the 21st century. Climate model simulations suggest net precipitation rates will increase across the region in the next 20 years, but there will likely be local decreases that will vary geographically and temporally. Climate model results suggest that the onset of the monsoon in Thailand, Laos, Cambodia and Vietnam may be delayed by 10-15 days during 2030-2070, but the duration of the monsoon will not change. There is no evidence from climate model simulations that Enso events will become more frequent due to climate change, but it is possible that their intensity may increase. Sea levels will continue to rise, although rates will vary across the region. By the end of the 21st century, sea level is projected to rise by approximately 30-40 cm. There is overwhelming evidence that climate change will impact a variety of sectors in Southeast Asia and Pacific Islands through 2030. All of the major effects of climate change on the region are interrelated, so it is impossible to assess one impact independently of the others. The most high-risk impacts are related to fresh water and ocean water resources, and include the following: Sea Level Rise – Rising sea level will cause a number of devastating effects in the region, including saltwater intrusion into estuaries and aquifers, coastal erosion, displacement of wetlands and lowlands, degradation of coastal agricultural areas and increased susceptibility to coastal storms. These effects are interrelated with impacts on agriculture, natural disasters, river deltas, water resources, coastal ecosystems, human livelihoods and infrastructure and national security. Sea level rise has overarching socioeconomic impacts as well, due to loss in income associated with degradation of agricultural areas and loss of housing associated with coastal inundation, for example. Water Resources – Future changes in regional water resources are closely tied to changes in precipitation. Individual areas under severe water stress in the region are projected to increase dramatically in the next few decades, although model results suggest that the region as a whole will not be at risk for water shortages. Fresh water resources on all island nations in the region are especially vulnerable to any variability in precipitation because many rely on rainwater collection for their supply of fresh water. The management of water issues is one of the most challenging climate-related issues in the region, as it is central to health and sustainable development. The impacts are interrelated on agriculture, river deltas, forests, coastal ecosystems, diseases and human health and national security. Agriculture – It is difficult to reliably simulate the complicated effects of future variations in temperatures, precipitation and atmospheric CO2 concentrations on crop growth. Temperature increases associated with climate change could result in a northward expansion of growing areas and a lengthening of the growing season. Rising atmospheric CO2 levels are expected to stimulate plant photosynthesis, which would result in higher crop yields. Studies show that the beneficial effects of CO2 on plants may be offset by average temperature increases of more than 2°C, however. Overall, it is likely that future crop yields will vary by region and by crop, with yield increases in some locations but decreases in others. The impacts of climate change on agriculture are interrelated with impacts on sea level, river deltas, natural disasters, water resources and national security. Coastal Regions – Coastal regions are some of the most at-risk areas due to their prevalence and high population density. Mangroves and coral reefs are two key coastal ecosystems expected to be significantly impacted by climate change. Many coastal areas are already degraded by pollution, sediment-laden runoff and destructive fishing practices. Climate change-related destruction and degradation of mangroves and coral reefs will only exacerbate these effects and result in long-term economic repercussions, since these ecosystems are central to the tourism, agriculture, fishing and aquaculture industries. The area's coastal regions are also susceptible to inundation associated with sea level rise and destruction of infrastructure from flooding and storm surges, which are likely to increase as a result of future climate change. Careful management and safeguarding of coastal regions by regional governments is therefore essential in the next 20 years, as the effects of climate change manifest themselves. Impacts on coastal regions are interrelated with sea level, river deltas, natural disasters, water resources, agriculture, forests and human livelihoods and infrastructure.
