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There are two methods of harvesting sugarcane—manual or mechanical. Manual harvesting requires the burning of the standing sugarcane crop. Burning of the crop results in the emission of aerosols and harmful trace gases into the atmosphere. This work makes use of a long-term dataset (1980–2019) to study (1) the atmospheric spatial and vertical distribution of pollutants; (2) the spatial distribution and temporal change of biomass emissions; and (3) the impact/influence of climatic factors on temporal change in atmospheric pollutant loading and biomass emissions over the Mpumalanga and KwaZulu Natal provinces in South Africa, where sugarcane farming is rife. Black carbon (BC) and sulfur dioxide (SO2) are two dominant pollutants in the JJA and SON seasons due to sugarcane burning. Overall, there was an increasing trend in the emissions of BC, SO2, and carbon dioxide (CO2) from 1980 to 2019. Climatic conditions, such as warm temperature, high wind speed, dry conditions in the JJA, and SON season, favor the intensity and spread of the fire, which is controlled. The emitted pollutants are transported to neighboring countries and can travel over the Atlantic Ocean, as far as ~6600 km from the source site.

In this study, seasonal, inter-annual variations of sulphur dioxide (SO 2) were analysed for Sharpeville, South Africa (27.86˚ E; 26.68˚ S) for the period 2007-2013. Sharpeville is a residential site located within a highly industrialised region. Inter-annual variations were investigated by analysis of data collated by a Ground-based (GB) instrument as well as the SO 2 retrievals recorded by the Ozone Monitoring Instrument (OMI), a satellite-based sensor. The Planetary Boundary Layer (PBL) SO 2 vertical column data recorded by OMI were converted to surface SO 2 volume mixing ratios using the pressure difference between surface and PBL. Accordingly, the OMI derived SO 2 measurements overestimated GB values and showed a good correlation with GB data in the austral winter. Besides this, the overall comparisons i.e. their daily, seasonal and yearly correlation studies found that OMI derived measurements was in better agreement with GB regardless of its moderate relative percentage of difference with GB. The seasonal variations of SO 2 demonstrated that GB and OMI derived measurements followed a general pattern of increasing trend from autumn until late winter and decreased from the onset of spring, 1 however the latter showed unique high SO 2 levels in summer. Together with this, the inter-annual variations of both computations displayed a small decrement in SO 2 values during the period 2011-2013. This however proved to be a stable variation when compared to other countries.