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2.5 CONCLUSION
ОглавлениеThe climate system in central Africa suffers from a lack of attention compared to other regions in Africa. A simplistic view of the annual rainfall regime over the region was adopted and associated with the north–south migration of the ITCZ, which suggests collocation of maximum temperature, low pressure, high cloudiness, and rainfall. This results from conjectures that were later found to be incorrect for the region. The wealth of regional studies over West Africa, East Africa, and southern Africa contributed to advances in the understanding of several mean climate features over the continent, which later on have shown importance for the climate regime over central Africa. In the effort to improve comprehension of the functioning of the central African climate, attempts to parallel other region concepts may be avoided as some climate features have shown differences in their interactions with the climate in central Africa and other regions (Cook, 2015). This may also prevent from misinformation, as was the case for the ITCZ concept.
A progressively clearer picture of the seasonal cycle over central Africa is emerging. Recent findings highlight lower‐level subsidence underneath areas of deep convection, which is mainly controlled by the mid‐tropospheric dynamics. This mid‐tropospheric dynamic is modulated by the mid‐level jets and shallow meridional cells over northern and southern central Africa, which are associated with heat lows over northern and southern Africa. Another progress is the contribution of Walker‐like circulation, with the lower‐level Congo Basin Cell controlling the location of maximum rainfall over eastern central Africa and the upper level Zonal Asymmetric Pattern. This suggests myriad feedbacks to shape the annual rainfall regime over central Africa. What controls lower‐level subsidence over central Africa and how these climate features contribute to the dynamic of mesoscale convective systems is unclear and merits further attention.
Central Africa borders on West Africa, East Africa, and southern Africa, which all have climate systems that benefit from a wealth of region‐specific studies. This fragmented approach contributed to the poor understanding of the central African climate. An integrated approach is required to provide an improvement in the understanding of central Africa’s climate as the region is influenced by features as Saharan heat low, Angola low, mid‐tropospheric easterly jets, and shallow meridional circulation driven by these lows. Lack of this integrated assessment in past studies (Hart et al., 2019) suggests that exploration of the manner in which the central, eastern, northern, and southern African climate systems are linked is crucial, thereby breaking the rigid regional view of the continent’s climate system. Climate models generally suffer from poor performance over central Africa compared to other regions in the continent. Indisputably, lack of knowledge on mechanisms driving central African climate significantly hampered efforts for model evaluation and exacerbates the issue of model deficiencies. However, the credibility of model projection relies on the plausibility of mechanisms driving changes. This underlines the need, while improving understanding of regional climate, to advocate efforts for process‐based evaluation of models over the region.
The wealth of climate research programs, and the related field experiment results, led to dramatic changes in the understanding of the picture of meteorology over some regions of Africa (e.g., the project African Monsoon Multidisciplinary Analysis [Redelsperger et al., 2006] over West Africa) and underlines unavoidability of this route for central Africa in order to improve in the understanding of the current variability of Earth’s climate and increase trustworthiness in the assessment of its future changes.