Climate Change in Malaysia

Southeast Asia is one of the three regions in the world that will be hit hardest by climate change1. The main impacts in Malaysia will be increasing temperatures, extreme weather events, and sea level rise.

Increasing Temperatures

An approximate increase of 3°C by 2100 is the current estimation for Malaysia if all unconditional Nationally Determined Contributions (NDCs) are implemented2. For comparison, 2ºC is the threshold at which climate change becomes a serious threat. Furthermore, the Urban Heat Island (UHI) effect, which warms cities 2-8ºC above surrounding rural or natural areas, will exacerbate this increase. Research also shows that the UHI is increasing, as cities are warming up 29% faster than rural areas3.

Jalan Brown, images taken at 9:57 a.m.

Lebuh Gereja, images taken at 10:59 a.m.

A difference of 29.8°C in surface temperature can be observed between the images taken at Jalan Brown, a partially shaded tree-lined street in the Northwest part of George Town, Penang and Lebuh Gereja, a non-shaded street in the UNESCO World Heritage Site of George Town, Penang.

Source: Produced by Think City with a Perfect Prime IR0006 Thermal Imager Camera on 12 July 2019.

Extreme Weather Events

An increase of 15% in absolute volume of rainfall was registered in the past 40 years4; average precipitation is predicted to increase further for all of Peninsular Malaysia5. There is also a clear trend of changes in rainfall patterns, with more concentrated rainfall and longer periods of drought.

In November 2017, Penang experienced its worst recorded flood due to strong winds and torrential rain from a tropical cyclone, which led to:

  • 7 lives lost6
  • 2,861 people forced to evacuate7
  • Floodwaters reaching a height of 10-12 feet in some places8
  • Losses to manufacturing at an estimated RM 200 and 300 million9

A combination of increased urbanisation, heavy rain, tides, and storm surges results in floods as stormwater cannot discharge into the sea or infiltrate the ground table. Expanding built areas result in reduced stormwater absorption capacity, and increased volume and concentration of rainfall have exposed Penang Island to flooding.

In December 2021, eight states in Peninsular Malaysia experienced flooding, which led to:

  • 55 lives lost10
  • 400,000 people forced to evacuate11
  • Floodwaters reaching a height of 13 feet in some places
  • Losses to manufacturing at an estimated RM 900 million

Sea Level Rise

Sea level rise poses several threats, including saltwater intrusion into rivers and aquifers and coastal erosion. Between 1984 and 2013, the total average sea level rose at a rate of 3.67 (± 0.15) mm/year in Malaysia, which is higher than the global average12. Projected sea level changes from 2001 to 2100 vary regionally, with the lowest projected changes expected at 2.53 mm/year and the highest at 5.17 mm/year13.

In Malaysia, 1,349.3 km of coastline constantly faces erosion, and of these, approximately 55.4 km falls under the Critical Erosion category. Projected sea level rise indicates that except for Labuan, 37 out of 344 areas of coastline under the Critical Erosion and Significant Erosion categories will be vulnerable to sea level rise by 203014.

Coastal erosion sites are classified into three categories:

  1. Critical: Areas suffering from coastal erosion where shore-based facilities are in imminent danger of loss or damage
  2. Significant: Areas where shore-based facilities are expected to be endangered within five to 10 years if there is no remedial action taken
  3. Acceptable: Erosion areas that are generally undeveloped with minor economic loss if erosion continues unabated

Impacts on Tree Species

Malaysia is one of the most biodiverse countries in the world. It has an estimated 5,200 tree species15, of which 2,830 occur in Peninsular Malaysia16 and 4,000 occur in East Malaysia (Sabah and Sarawak). There is an overlap of 30% or 1,559 species between the two regions.

Trees are vital for addressing some of the major problems society faces due to climate change, both in mitigation and adaptation. They are especially effective in reducing urban heat, so international organisations such as the United Nations (UN) strongly encourage urban greening as a global solution. However, the climate in 2050 will be different from the climate today, and some species will not be able to adapt to the new urban habitat. Considering that urban trees are planted with a perspective of a minimum life cycle of 50 years, understanding which species are more resilient to the coming changes in climate is critical for responsible, future-oriented urban forest management.

Examples of Urban Greening

Several recent studies have demonstrated the vulnerability of urban tree species to climate change and addressed the need to understand the resilience of urban tree species to climate change impacts:

  • A study in Shanghai evaluated 65 urban tree species and developed an adaptability assessment framework to address the impacts of climate change17
  • A study in Australia subjected 20 tree and shrub species to heat and drought stresses and found that water loss at high temperatures can drive species towards mortality thresholds faster than expected18
  • A study on climate change and urban forests in 164 cities across 78 countries found that urban trees are most at risk in cities at low latitudes, such as New Delhi and Singapore19

The threats to urban habitats that tree species in Malaysia face are mainly related to heat stress, flooded root systems, and saltwater intrusion. These environmental stressors will also cause trees to be more susceptible to damage by insects, fungi, and disease. A continuous process of mapping the impacts of climate change on tree species and sharing this knowledge with professional organisations and local governments will provide long-term environmental, social, and economic benefits.


  1. Masson-Delmotte, Valérie, Panmao Zhai, Hans-Otto Pörtner, Debra Roberts, Jim Skea, Priyadarshi R. Shukla, Anna Pirani et al. "Global Warming of 1.5 ºC: An IPCC Special Report on the Impacts of Global Warming of 1.5ºC Above Pre-Industrial Levels and Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change, Sustainable Development, and Efforts to Eradicate Poverty.” (2018).
  2. League, Earth, Pavel Kabat, Paul Egerton, Omar Baddour, Laura Paterson, Clare Nullis, Sylvie Castonguay, and Melissa Walsh. "United in Science: High-level Synthesis Report of Latest Climate Science Information Convened by the Science Advisory Group of the UN Climate Action Summit 2019." (2019).
  3. Liu, Zihan, Wenfeng Zhan, Benjamin Bechtel, James Voogt, Jiameng Lai, Tirthankar Chakraborty, Zhi-Hua Wang, Manchun Li, Fan Huang, and Xuhui Lee. "Surface Warming in Global Cities is Substantially More Rapid than in Rural Background Areas." Communications Earth & Environment. (2022).
  4. National Hydraulic Research Institute Malaysia (NAHRIM). “The Study of the Impact of Climate Change on Sea Level Rise in Malaysia (Final Report).” (2010).
  5. Ministry of Energy, Science, Technology, Environment and Climate Change (MESTECC). “Malaysia: Third National Communication and Second Biennial Update Report to the UNFCCC.” (2018).
  6. “Penang Flood Death Toll Climbs to Seven, Three by Drowning.” Malay Mail. (2017).
  7. Mok, Opalyn. “Close to 3,000 Victims Evacuated, Thousands More Affected by Penang Floods.” Malay Mail. (2017).
  8. Shiying, Crystal Chiam. “Penang Paralysed by Floods.” The Star. (2017).
  9. Lee, Esther. “The State of the Nation: Penang Floods Likely to Have ‘Minimal Disruption’ on Economic Activities.” The Edge Malaysia. (2017).
  10. Zainal, Fatimah. “Floods: 55 Fatalities from December 2021 to January 2022.” The Star. (2022).
  11. Rahman, Serina. “Malaysia’s Floods of December 2021: Can Future Disasters be Avoided?” ISEAS Perspective. (2022).
  12. Kamaruddin, Abdul Hadi, Ami Hassan Md Din, Muhammad Faiz Pa'suya, and Kamaludin Mohd Omar. "Long-Term Sea Level Trend from Tidal Data in Malaysia." 2016 7th IEEE Control and System Graduate Research Colloquium (ICSGRC). (2016).
  13. Ercan, Ali, Mohd Fauzi Bin Mohamad, and M. Levent Kavvas. "The Impact of Climate Change on Sea Level Rise at Peninsular Malaysia and Sabah–Sarawak." Hydrological Processes. (2013).
  14. Ministry of Energy, Science, Technology, Environment and Climate Change (MESTECC). “Malaysia: Third National Communication and Second Biennial Update Report to the UNFCCC.” (2018).
  15. Saw, L. G., and R. C. K. Chung. "The Flora of Malaysia Projects." Rodriguésia. (2015).
  16. Ng, F.S.P., C.M. Low, and Mat Asri Ngah Sanah. “Endemic Trees of the Malay Peninsula.” (1990).
  17. Liu, Ming, Deshun Zhang, Ulrich Pietzarka, and Andreas Roloff. "Assessing the Adaptability of Urban Tree Species to Climate Change Impacts: A Case Study in Shanghai." Urban Forestry & Urban Greening. (2021).
  18. Marchin, Renée M., Diana Backes, Alessandro Ossola, Michelle R. Leishman, Mark G. Tjoelker, and David S. Ellsworth. "Extreme Heat Increases Stomatal Conductance and Drought‐Induced Mortality Risk in Vulnerable Plant Species." Global Change Biology. (2022).
  19. Esperon-Rodriguez, Manuel, Mark G. Tjoelker, Jonathan Lenoir, John B. Baumgartner, Linda J. Beaumont, David A. Nipperess, Sally A. Power, Benoît Richard, Paul D. Rymer, and Rachael V. Gallagher. "Climate Change Increases Global Risk to Urban Forests." Nature Climate Change. (2022).