Evaluation of Global Emissions from Small Combustion Activities Sector: Sources of Uncertainties and Improvements in EDGAR

Fuel combustion for heating (thermal capacity ≤ 50 MW_th) and cooking contributes significantly to the emissions affecting human health. For example, in Europe, this sector had the largest share for Benzo[a]pyrene (BaP) and PM_2.5 emissions in 2015 (EEA, 2017). Accurate emission estimates for this sector are essential to evaluate their impacts on environment and human health. Here, we focus on two major sources of uncertainties: the activity data from statistics on fuel consumption and the emissions distribution on gridmaps.

Firstly, we explore the improvements in activity data for all world countries by analyzing the changes in fuel consumption for the year 2008 in two different activity data releases. Using the Emissions Database for Global Atmospheric Research (EDGAR) methodology, two emissions datasets are compiled for the year 2008. We will discuss the changes in the levels of air pollutants due to the differences between the old (2010) and revised activity data (2017). Significant changes are seen e.g. for PM_2.5 in Italy, Nigeria, Pakistan, Indonesia, India and Bangladesh; the differences are provided in Figure 1 for all world countries. This shows that some countries revised their statistics on fuel consumption. We provide evidence, for biomass in particular, by presenting the outcome of case studies performed in the Danube Region. Consumption could be up to three times higher than the quantities reported before the revision of statistics by adding the self-production part; estimations based on energy demand show even higher differences.

Secondly, given the local impact of emissions from the small combustion activities sector, we used an advanced proxy of Global Human Settlement Layer (GHSL) that provides a refined degree of urbanization to improve the emissions distribution for all world countries. We will describe the methodology and analyze the changes in emissions distribution pattern; an example is provided in Figure 2a and 2b for BaP.

Finally, we will present the impact of air pollutants on human health resulting from these emissions improvements using the Fast Scenario Screening Tool (TM5-FASST) source-receptor model. The new EDGAR release, which uses the activity data of IEA (2017) for emissions estimation and advanced proxy for emissions distribution, can provide a better input to the models.