Constraining the uncertainties of key climate-affecting components from African large-scale fires

Large-scale biomass fires in Africa emit vast amounts of aerosols and gases into the atmosphere, perturbing the regional climate.

In this project, we address the large uncertainties related to the climate impact of key, but poorly constrained, climate-warming components from these emissions: light-absorbing aerosols and carbon monoxide (CO).

The knowledge-status of these components are particularly low for the rapidly developing African region, owing to the lack of long-term ground-based observations.

Here, we continue our long-term involvement at the Rwandan Climate Observatory (RCO): a unique mountain receptor site for capturing the regional air mass footprint from central and eastern Africa.Filter samples and flask samples will be collected year-round at RCO, ensuring capture of the two annual dry biomass emission maxima.

The samples are sent to Stockholm University for chemical and multi-isotope analysis, allowing detailed assessment of sources and atmospheric processing.

These characteristics are then linked to physical properties such as aerosol light-absorption and atmospheric lifetimes – of key importance for estimating climate warming effects. The observational results will then be compared to an atmospheric chemistry-transport model.

Overall, this project address key uncertainties regarding the environmental impact of light-absorbing aerosols and CO, of central importance for sustainable development in Africa. These results will be communicated to key stakeholders.