Spatiotemporal variability of formaldehyde content in atmospheric air according to satellite measurements

Formaldehyde (HCHO) is a key ingredient in atmospheric chemistry, a precursor to ozone (O3) and an important indicator of atmospheric photochemical activity. It is also known to be a human and animal carcinogen. To assess the spatial and temporal variability of the formaldehyde content, the article analyzes long-term data (2003–2016) of measurements of the OMI spectrometer located on the Aura satellite. The results of the analysis showed that the tropospheric content of formaldehyde over most of the territory of Belarus for 2003–2016 had an uneven spatial distribution: there is a decrease in concentrations in the direction from the southwest to the northeast. Large cities and industrial centers form zones of increased troposphere pollution. The content of formaldehyde in the cells over the territory of Belarus during the study period was in the range of up to 30.8×1015 mol/cm2 and averaged 6.5×1015 molec./cm2. In most of the obtained values (84.1 %), the formaldehyde concentrations were fixed within the range of 2.0–10.0×1015 molec./cm2, and only 0.6 % exceeded 15.0×1015 molec./cm2. The obtained data are compared with the data of the ground-based atmospheric air monitoring system. The content of formaldehyde in the troposphere over the territory of Belarus, as well as in the surface layer of the atmosphere, has a pronounced seasonal dynamics with a maximum in the warm season with the highest concentrations in July and August. An analysis of the intra-annual dynamics of formaldehyde content in the surface layer and in the troposphere column indicates the presence of general trends, both for Belarus as a whole and for individual cities.1