Outcomes & Impact

The issues of climate change and air pollution are truly international. Per unit of mass, black carbon has a warming impact on climate that is 460-1500 times stronger than that of CO2, which makes its monitoring and mitigation important for early reductions in current global warming predictions. The breadth and depth of the challenges that need to be overcome to provide traceability for BC-related optical and mass concentration measurements require an extensive range of expertise. The scope of this project is therefore beyond the capabilities of a single NMI and a pan-European approach is essential in order to deliver the work.

Normative projects tackling global challenges, such as pollution and its detrimental effects on public health, must achieve wide consensus in order to harmonise procedures in Europe (and worldwide). They rely therefore by nature on the close collaboration between countries and the will to align national regulations. The EPM programme, bringing together NMIs, research institutes, instruments manufacturers and experts from air quality monitoring networks across Europe, is the ideal platform for the work described in this project.

The EMPIR 16ENV02 Black Carbon and 18HLT02 AeroTox projects have greatly contributed to the development and characterisation of novel aerosol instruments (including a soot generator, the oxidation flow reactor known as OCU, and the photo-thermal interferometer PTAAM-2λ). All these are manufactured in Europe and will be employed in the calibration procedure for filter-based absorption photometers either as reference aerosol sources or as reference measurement methods. Moreover, several manufacturers of filter-based absorption photometers are based in the EU. This project will enhance the end users’ confidence in these instruments through standardisation, promote sales and help European manufacturers assume a leading role in the global market.

The direct impact of the proposed research will be more accurate and more comparable measurements of aerosol light-absorption coefficient and better estimates of eBC mass concentration than in the current status of the widespread aerosol monitoring networks in Europe, through the standardisation of traceable methods for calibrating filter-based absorption photometers.

Indirectly, the impact would be very widespread. In terms of scientific benefits, the improved measurements would fit into EU atmospheric aerosol projects, refining climate change models, and improving the quality of conclusions from cohort health studies looking at the health effects of air pollution. Air quality measures to reduce human exposure to BC such as emission reduction and low emission zones have already been taken.

However, traceable BC-related metrics to reliably quantify the success of these measures are not yet available. The results of this project will feed directly into national air quality monitoring networks across Europe. The improved measurement accuracy will also help set up reliable black carbon emission inventories.

Currently, there are no legislated limits for BC for outdoor air concentrations, only the total mass of fine particles is regulated. This is partly due to the fact that there is no well-defined metric for BC mass concentration in ambient air. Ultimately, the project will provide a CEN standard on BC-related metrics and form the basis for future European legislation.

According to WHO “…air pollution imposes a large economic cost on the countries of the WHO European Region. As at 2010, the annual cost of premature deaths from air pollution across the countries of the WHO European Region stood at EUR 1.4 trillion, and the overall annual cost of health impacts from air pollution stood at EUR 1.6 trillion”. Thus, even a small decrease in health effects from air pollution would lead to substantial economic benefits.