Greenhouse Gas Emissions; GHG Inventory; Road Transport Sector; Improved Activity Data; 2006 IPCC Guidelines; Malaysia
Abstract
The road transport sector contributes significantly to global greenhouse gas (GHG) emissions because of its reliance on fossil fuels. In Malaysia, emissions from this sector have shown a steady rise over the past few decades, highlighting the need for more precise estimation methods to strengthen climate and energy policy development. This study seeks to enhance the accuracy of activity data applied in national GHG inventory estimation by adopting the Tier 2 methodology as recommended in the 2006 IPCC Guidelines. The analysis focuses on the 2019 and emphasises disaggregation of fuel consumption data by vehicle type and fuel category. Findings reveal that GHG estimates derived using the Tier 2 approach differ by approximately 59% for CO₂, 48% for CH₄, and 56% for N₂O compared to Tier 1 results, reflecting the influence of data assumptions and methodological complexity. The study highlights the importance of enhancing national data systems and country-specific emission factors to improve reporting accuracy. Improved data granularity also provides a foundation for data-driven decision making and future integration of digital monitoring and AI-based analytical tools in the transport sector.