Keywords :
MAX-DOAS, KINSHASA, NO2, H2CO, TROPOMI
Abstract :
[en] Many African cities are affected by the problem of air pollution as mentioned in
the study by Louisse et al 2014 stating that air quality in African urban areas is
expected to deteriorate in the coming decades.
The city of Kinshasa, the capital of the Democratic Republic of Congo (DRC), a
large megalopolis of 12 million inhabitants, with an estimated population of 30
million by 2030 UN (2016), is not spared by this air pollution as shown in
McFarlane et al. (2020) and WHO reports. It is dominated by a multiplication of
motorcycles, old vehicles, open garbage cans, unpaved roads and the use of
embers from forest wood as energy for cooking. Its surroundings are also affected
by seasonal forest burning, which is a potential source of several pollutants,
including NO2 and H2CO.
However, measurements are lacking, and this limits the number of studies address
this topic in this region of the world. Even with regard to the worldwide
distribution of atmospheric measurement stations (e.g. via the NDACC network
www.ndacc.org), it can be seen that Central Africa is largely under-sampled
compared to other land areas of the globe. Although satellite observations exist in
this region, they are generally unsuitable for sampling over heavily polluted areas
due to their low sensitivity near the surface, and the consequences can be directly
related to the inaccuracy of the corresponding emission estimates by top-down
approaches. Ground-based measurements are and will remain essential for
atmospheric research, whatever the future progress of satellite instruments and
the refinement of models. Therefore, measurements in this region are of particular
interest in order to know the temporal and spatial distribution of NO2 and H2CO
emission intensity at the local scale and also in order to understand the accuracy
of satellites and models.
It is in this perspective that the present work is inscribed, with the objective of
presenting a series of atmospheric measurements of NO2 and H2CO, going from
November 2019 to July 2021, with as vision: 1. to make a validation of the
TROPOMI satellite, 2. to evaluate the performance of the GEOS-Chem model to
constrain the emissions in this area.
