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Release of major assessment of the state of the environment in Southeast Asia

The Association of Southeast Nations (ASEAN) in collaboration with SEI has published its ASEAN Fifth State of the Environment Report, which shows environmental challenges growing in number and complexity.

Expressway traffic in Bangkok seen from Baiyok tower. Photo: wnjay_wootthisak / Getty Images.

Rajesh Daniel / Published on 18 January 2018

Studies predict a 4.8°C rise in mean annual temperature and a mean 70cm rise in sea level rise by 2100 in Indonesia,the Philippines, Thailand and Viet Nam, putting tens of millions of coastal dwellers at risk.

  • By 2050, two-thirds of the region’s population will be concentrated in urban areas, increasing pressure on urban infrastructure and natural habitats.
  • Burning and clearing of forests and peatlands continues to contribute to transboundary haze, especially from Indonesia, which is considered the number one fire hotspot in the region due to rapid expansion of pulpwood and oil palm plantations.
SEI ASEAN SOER Cover 350x175
 ASEAN Fifth State of the Environment Report cover page. Source: ASEAN Cooperation on Environment

The report focuses on six critical environmental issues: air pollution, including transboundary haze; land and forests; biota and ecosystems; freshwater; oceans and marine ecosystems; and the need for more sustainable production-consumption systems to drive ASEAN to a more resource-efficient future.

The report provides a comprehensive assessment of these topics and ways to address them through increased regional cooperation using institutional and policy frameworks.

SEI Asia was commissioned by the ASEAN Secretariat to produce the fifth regional environmental assessment.


Among the various socio-economic trends contributing to increased environmental changes in the ASEAN region, rapid urbanization is leading to increased air and water pollution as well as growing amounts of waste.

Over the last two decades, ASEAN’s urban population has been growing at an annual rate of 2.65%, twice the rate of the overall population growth. By 2050, it is projected that two-thirds of ASEAN’s population will be concentrated in urban areas.

ASEAN governments are finding it difficult to cope with the rapid increases in theurban population that are fast outpacing their efforts to build betterinfrastructure in cities.

Meanwhile, more infrastructure such as roads to meet the growing demands for inner-city transport is exacerbating air and water pollution.

“ASEAN’s urban expansion has also led to significant conversion of natural habitats”, said Pin Pravalprukskul, research associate with SEI Asia and author of the SOER’s biota and ecosystems chapter. At the beginning of the century, biodiversity hotspots covered more than half of the region’s urban areas. But it is projected that by 2030, more protected areas in the ASEAN region will be within 10km of a city than in any other region globally.

ASEAN is trying to deal with this challenge: for instance, ASEAN convened the East Asian Summit (EAS) Seminar on Sustainable Cities in Chiang Rai, Thailand in February 2017. Later in June, an ASEAN Congress brought together researchers, development practitioners and policy experts to exchange and discuss experiences on sustainable urbanization.

Climate change, disasters and vulnerability

The ASEAN region has been experiencing climate change impacts such as irregular precipitation and increasing sealevel rise (1-3 mm per year).

Studies predict a 4.8°C rise inmean annual temperature and a mean 70cm rise in sea level by 2100 in Indonesia,the Philippines, Thailand and Viet Nam, putting tens of millions of coastal dwellers at risk.

Most at most risk from coastal flooding are the millions living in the coastal areas of Viet Nam, Thailand, Myanmar,Cambodia, Philippines, Malaysia, Indonesia and Brunei Darussalam.

In part due to climate change, the frequency and intensity of hydrological, meteorological and climatological disasters has been increasing over the last 50 years, particularly compared to geophysical disasters, at leastin part due to the impact of climatechange on disaster frequency and intensity.

Southeast Asia is one of the most at risk regions in the world to the impacts of climate change, with forecasted rankings showing six of the twenty countries most vulnerable to climate change worldwide being Indonesia, Thailand, Myanmar, Malaysia, Viet Nam and the Philippines.

Sea level projections for 2050 suggest that populations across ASEAN are at increasing risk from sea level rise resulting from climate change, including in Indonesia (20 million people at risk), the Philippines (15 million), and Viet Nam (10 million), and to a lesser extent, Malaysia, Myanmar and Thailand.

Transboundary haze

This regular, seasonal occurrence from July to September is a persistent challenge for ASEAN. The haze is caused by the burning and clearing forested areas, in particular peatlands, for commercial tree plantations primarily of oil palm. Indonesia is considered the number one fire hotspot in ASEAN due to its rapid expansion of pulpwood and oil palm plantations [Figure 14].

There have been efforts to tackle the haze pollution problem, including the full ratification of the ASEAN Agreement on Transboundary Haze Pollution (AATHP), which came into force in 2003, and the creation of the recent Roadmap on ASEAN Cooperation towards Transboundary Haze Pollution Control with Means of Implementation (2016). But much more still needs to be done including stronger commitments by the countries to implement better land management practices and monitoring of illegal land clearance.

ASEAN action

One of the report’s most important warnings is that ASEAN can expect greater disasters if future climate change impacts are not considered in national development and disaster risk reduction (DRR) policies and strategies.

ASEAN has addressed this critical issue with its 2015 ASEAN joint statement on climate change adopted at the 13th ASEAN Ministerial Meeting on Environment, in Hanoi in February 2017.

Moreover, ASEAN’s Strategic Plan on Environment (ASPEN) that is to be adopted in 2017, will guide action on environmental challenges common in ASEAN region. ASPEN also will support ASEAN to realize its Community Vision 2025 particularly on environmental cooperation. SEI has been part of also developing the ASPEN in collaboration with the ASEAN Secretariat.

Niall O’Connor, Centre Director of SEI’s Asia Centre said: “By undertaking this vast assessment of the environment for ASEAN, SEI has looked at the many critical and multi-faceted environmental impacts presently faced by this region.

“SEI has assessed how science-based evidence can help support decision-makers throughout the region, to make the informed and right choices in national and regional policy decisions. Working together, with informed governments, civil society and the private sector, and critically, with the vast young and educated populations of ASEAN, SEI believes it is possible to turn away from this destructive development pathway towards a more sustainable and prosperous future for all.”

Read the ASEAN Fifth State of the Environment Report»

Watch insights from SEI researchers on the ASEAN Fifth State of the Environment Report


Thanapon Piman
Thanapon Piman

Senior Research Fellow

SEI Asia

Niall O’Connor

Centre Director

SEI Asia

Natalia Biskupska

Manager, Programme Operations

SEI Asia

Rajesh Daniel

Head of Communications, SEI Asia


SEI Asia

Profile picture of Agus Nugroho
Agus Nugroho

Programme Manager

SEI Asia

Albert Salamanca
Albert Salamanca

Senior Research Fellow

SEI Asia

Profile picture of Frank Thomalla
Frank Thomalla

SEI Affiliated Researcher

SEI Asia

Topics and subtopics
Governance : Sustainable Development Goals
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