An extensive inventory of municipal open waste burning nationwide based on machine learning analysis

BACKGROUND AND OBJECTIVES: Residential open waste burning remains a major environmental and climate challenge in Indonesia. Th study objectives were to conduct a comprehensive nationwide
assessment of open burning by measuring its prevalence, recognizing spatial patterns, examining material composition, and revealing the behavioral influences that contribute to it. The ultimate objectives of this study were to generate evidence-based insights that can inform targeted policies and interventions to reduce open waste burning and its associated impacts.

METHODS: The study integrates multiple approaches, including national datasets, a large-scale household survey, spatial analysis, and topic modelling of qualitative responses. The estimation of waste burning activities was conducted through a framework derived from the Intergovernmental Panel on Climate Change's activity and emission inventory, with a crucial improvement that integrated the official administrative classifications of Indonesian villages and cities to more precisely allocate uncollected waste fractions at the subnational level. Primary data were collected via an online questionnaire, yielding 722 valid responses distributed across major regional clusters in Indonesia, including Java, Sumatra, Kalimantan, Sulawesi, Bali–Nusa Tenggara, and eastern regions, characterizing household waste generation, disposal practices, and behavioral drivers.

FINDINGS: The results indicate that in the reference year, approximately 26.6 million tonnes of municipal waste were estimated to be openly burned in Indonesia, corresponding to about 23.3 million tonnes of carbon dioxide equivalent emissions. Residential combustion represents approximately 70 percent of the overall waste incinerated, significantly surpassing the contributions from landfill fires. Spatial analysis revealed strong clustering of open waste burning in densely populated provinces, particularly on Java Island, with notable intra-provincial variation at the district level. Analysis of material composition revealed that dry and combustible components, including plastics, paper, wood, and garden waste, were disproportionately present in the incinerated waste. Latent Dirichlet Allocation topic modelling identified inadequate waste collection infrastructure and household convenience as dominant drivers of open burning.

CONCLUSION: This study illustrates that open burning is a prevalent and serious concern in Indonesia, leading to considerable climate and environmental consequences. Given that residential burning constitutes approximately 70% of the 26.6 million tonnes incinerated annually, targeted improvements in household waste collection services present significant opportunities to decrease emissions.