Cambodia is highly vulnerable to the effects of climate change. According to the 2020 Global Climate Risk Index, Cambodia was ranked as the 12th most climate risk-prone country globally, showing the high-level of vulnerability of the country to extreme weather events. Beyond extreme weather events, climate change also results in slow-onset events that can have significant negative implications for Cambodia and its people .
Cambodia is projected to experience warming of 3.1°C by the 2090s, against the baseline conditions over 1986–2005 under the highest emissions pathway, RCP8.5 . Increases in annual maximum and minimum temperatures are expected to be larger than the rise in average temperature, increasing pressures on human health, livelihoods, and ecosystems. For instance, heat stress represents a major threat to human health in Cambodia, especially for outdoor laborers and urban populations. Climate change may also increase the likelihood of transmission of water and vector-borne diseases, but this area requires further research .
Cambodia has extremely high exposure to flooding, including, riverine and flash flooding. Projected climate change trends indicate more severe floods and droughts, which is expected to affect Cambodia’s GDP by nearly 10% by 2050 . Without action, the population exposed to an extreme river flood could grow by around 4 million by the 2040s, however human development factors such as the damming of the Mekong River as well as the large-scale dams built on its tributaries, may alter future flood dynamics , . The country also has some limited exposure to tropical cyclones and their associated hazards, and drought although exposure is slightly lower, is still of significant concern, as highlighted by the severe drought of 2015–2017 .
The sectors most affected by climate change are agriculture, infrastructure, forestry, human health, and coastal zone areas which are particularly vulnerable to sea level rises and intrusion . Climate change and human influences, such as upstream dam construction and deforestation, over the Mekong River’s hydrological regime threaten to reduce the productivity of the Tonle Sap Lake and Cambodia’s fisheries – a significant threat to the livelihoods and nourishment of many poor, rural communities .
Many of the climate changes projected are likely to disproportionately affect the poorest groups in society. Rural areas face some of the most serious climate change threats. As subsistence agriculture remains prevalent in Cambodia, and rates of undernourishment high, the threat of yield reductions in staple crops and the potentially high cost of adaptation also represent major risks. While climate change is only one of many pressures on livelihoods in the vicinity of the Tonle Sap Lake, the low adaptive capacity of rural communities in this area, particularly their limited ability to diversify income sources, demands attention. Ultimately, research has shown that if increases in environmental stressors make traditional livelihoods less stable or tenable, migration is likely to result. Migration may take many forms: migration from rural to urban areas is already happening at a rapid pace, as is international migration. Without adequate planning such migration can often lead to transfer or creation of new types of risk .
Cambodia’s greenhouse gas emissions are low compared to most countries; however, it is going through a rapid economic growth that has rendered the country increasingly carbon intensive.
As reported in Cambodia’s GHG Inventory within the First Biennial Update Report (BUR) to the UNFCCC, GHG emissions increased by 285% between 1994 and 2016, and GHG emissions increased across all sectors. The first biggest emitting sector in the country was the Forest and Other Land Use (FOLU) sector driven by the change in carbon stocks, primarily due to deforestation. The sharp increase in the emissions of the AFOLU from year 2010 is due to the major deforestation experienced during these years (the economic land concessions had increased significantly from 2009).
Agriculture represents the second largest emitter sector in the country. Cambodia’s economy is heavily influenced by the contribution of agriculture to total GDP, which is also reflected in emission patterns. The main driver for the increase in GHG emissions is the development of rice cultivations.
In the time span covered by the inventory, Cambodian GDP experienced significant expansion, along with its population. This is reflected in the increasing trend of emissions of the third and fourth largest emitter sectors in the country, the Energy and Waste sectors, respectively. Energy demand has experienced a significant increase, the transport sector is expanding, while the population migrates to cities; all these factors lead to increasing fuel consumption and higher GHG emissions in the energy sector. The increased population and changes in waste management and sanitation are the main drivers for waste sector emissions. Finally, the small size of the carbon intensive-industrial sector in the country makes the Industrial Processes and Product Use (IPPU) the fifth contributor to national total GHG emissions. Nevertheless, the IPPU sector emissions experienced a growing expansion in the last period of the series, due to the rising contribution of cement production and consumption of fluorinated gases .
Key policies and governance approach
The Royal Government of Cambodia (RGC) is committed to combating climate change and has already made remarkable progress in terms of climate change policy, particularly in mainstreaming climate change into national and sub-national planning . The Cambodia National Policy on Green Growth, the National Green Growth Strategy, National Strategic Development Plans (NDSPs), the National Forest Program and the National Environmental Strategy and Action Plan, among others, are being implemented to guide future development towards sustainable, low-carbon and climate-resilient development .
The RGC has developed and continues to implement the Cambodia Climate Change Strategic Plan 2014 – 2023 (CCCSP) (2013), and fourteen relevant ministries and agencies have developed associated sectoral action plans (CCAPs) , . The CCCSP aims at building a greener, low-carbon and climate-resilient, equitable, sustainable, and knowledge-based society to contribute to global efforts to addressing climate change . The strategic objectives are to: (i) promote climate resilience through improving food, water and energy security; (ii) reduce vulnerability of sectors, regions, gender and health to climate change impacts; (iii) ensure climate resilience of critical ecosystems, biodiversity, protected areas and cultural heritage sites; (iv) promote low-carbon planning and technologies to support sustainable development; (v) improve capacities, knowledge and awareness for climate change responses; (vi) promote adaptive social protection and participatory approaches in reducing loss and damage; (vii) strengthen institutions and coordination frameworks for national climate change responses; and (viii) strengthen collaboration and active participation in regional and global climate change processes .
In 2020, Cambodia submitted its first Biennial Update Report (BUR) and its updated NDC to the UNFCCC, and the Third National Communication (TNC) work is underway. In addition, the National Monitoring and Evaluation (M&E) Framework for the response to Climate Change has also been developed and regular climate public expenditure reviews have been undertaken. Cambodia has also improved the tracking of climate finance in its Official Development Assistance (ODA) database, among many other initiatives .
Cambodia’s Updated Nationally Determined Contribution (NDC) (2020) sets a mitigation target of reducing GHG emissions compared to business as usual (BAU) by 42% by 2030 and includes a strong set of adaptation actions, which remain the top priority for Cambodia. An ambitious target has been set in the Forestry and Land Use sector (FOLU) of halving the deforestation rate by 2030, in line with Cambodia’s REDD+ strategy. The updated NDC also pays particular attention to gender and vulnerable groups, in order to ensure that adaptation and mitigation actions contribute to a more inclusive society. Finally, a significant effort has been made to develop a solid framework for measurement, reporting and verification (MRV), so that credible evidence on progress made and on challenges encountered can be generated .
SUCCESSES AND REMAINING CHALLENGES
A key barrier for climate actions in Cambodia is limited resources: human, technical and financial resources, which could be enhanced with support from development partners and private sector financing .
Although many policies and strategies addressing climate change impacts have been developed, their implementation remains limited due to insufficient financial support. Development partners remain the largest source of funding for climate change responses (64% in 2017), and fluctuations in external climate change financing are affecting Cambodia’s capacity to implement actions on mitigation and adaption to climate change . The implementation of Cambodia’s NDC requires over US $ 5.8 billion for mitigation actions, and just over US $ 2 billion for adaptation actions, with most actions conditional upon international support .
There is also a need to enhance capacity and technical skills in data and information collection and management, particularly for Measuring, Reporting and Verification (MRV). For instance, Cambodia retains limited experts and researchers in the fields of GHG inventory and mitigation, climate vulnerability assessment and adaptation measures, climate change and energy, climate agronomists, climate economists, etc. Capacity building of climate change national experts, as well as expertise retention remain key challenges in achieving the successful implementation of climate change projects . Other barriers include limited staff capacity at the sub-national levels in implementing adaptation and mitigation actions, as well as coordination with line ministries and other stakeholders (civil society, community-based organizations, NGOs, and the private sector) to ensure that efforts and resources are concerted, and synergies are leveraged . International support will be required for capacity strengthening and technology transfer .
Initiatives and Development Plans
To accelerate the country’s adaptation and mitigation goals, Cambodia has partnered with the ‘Scaling up Climate Ambition on Land Use and Agriculture through nationally determined contributions (NDCs) and National Adaptation Plans’ (SCALA) programme, funded by Germany’s International Climate Initiative (IKI). Over the next five years, Cambodia will be supported by the SCALA programme to strengthen coordination on climate action between ministries, the private sector and community-based organizations to support transformative change in the agriculture and land use sectors in alignment with adaptation and mitigation priorities outlined in the NDC and NAP .
In addition, locally led adaptation is fighting rainfall variability and unsustainable practices across several community protected areas in Cambodia. A UNEP project, financed by the Adaptation Fund and executed by Cambodia’s Ministry of Environment, that ran from 2013 to 2019, has trained thousands of people to adapt and, more importantly, lead on climate change efforts in Cambodia. The ‘Enhancing climate change resilience of rural communities living in protected areas of Cambodia’ project was largely focused on ecosystem-based adaptation activities by planting multi-use native tree species – providing food, erosion control, timber, and medicine – and rice types which need little water, to overcome years with longer drought seasons. Training on a number of skills was carried out in households and schools across the regions . Almost 950,000 indigenous trees have been planted, nearly 2,000 families have benefitted from increased agricultural yield, and a total of 1,875 hectares of community forests have been improved and restored. Just over 1,500 households across the project sites also reported an improvement in water access after rainwater harvesting techniques were implemented , .
To address the emerging issue of climate change, the main opportunities are :
- Mainstreaming climate change mitigation and adaptation into other policies.
- Building resilience to climate change.
- Improving climate change data accessibility.
- Addressing the missing information and data needs.
 Willner, S., Levermann, A., Zhao, F., Frieler, K. (2018). Adaptation required to preserve future high-end river flood risk at present levels. Science Advances: 4:1. URL: https://advances.sciencemag.org/content/4/1/eaao1914.
 The General Secretariat, the National Council for Sustainable Development/Ministry of Environment, the Kingdom of Cambodia (2020). FIRST BIENNIAL UPDATE REPORT OF THE KINGDOM OF CAMBODIA TO THE UNITED NATIONS FRAMEWORK CONVENTION ON CLIMATE CHANGE.
 FAO (2021). [Online]. Available: https://www.fao.org/in-action/scala/news/news-detail/cambodia-strengthens-climate-action-coordination-with-ministries-private-sector-and-community-based-organizations/en.
 Climate Home News (2021). [Online]. Available: https://www.climatechangenews.com/2021/12/13/locals-lead-adaptation-efforts-drought-stricken-cambodian-forests/.
 General Directorate of Environmental Knowledge and Information (GDEKI), Ministry of Environment Cambodia (2021). Fourth State of Environment Report.