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The possible role of local air pollution in climate change in West Africa

Abstract

The climate of West Africa is characterized by a sensitive monsoon system that is associated with marked natural precipitation variability. This region has been and is projected to be subject to substantial global and regional-scale changes including greenhouse-gas-induced warming and sea-level rise, land-use and land-cover change, and substantial biomass burning. We argue that more attention should be paid to rapidly increasing air pollution over the explosively growing cities of West Africa, as experiences from other regions suggest that this can alter regional climate through the influences of aerosols on clouds and radiation, and will also affect human health and food security. We need better observations and models to quantify the magnitude and characteristics of these impacts.

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Figure 1: Sea breeze, clouds and pollution.
Figure 2: Clouds and the West African monsoon.
Figure 3: Trends in West African population and settlement patterns.
Figure 4: Emission inventories and scenarios.
Figure 5: Atmospheric chemistry and its impacts over West Africa.

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Acknowledgements

The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement 603,502 as part of the DACCIWA project. We thank M. Maranan for creating Fig. 1, and R. Redl and R. van der Linden for creating Fig. 2.

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P.K. led the drafting of the text with input from the other authors on specific aspects. All authors contributed to the intellectual content.

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Correspondence to Peter Knippertz.

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Knippertz, P., Evans, M., Field, P. et al. The possible role of local air pollution in climate change in West Africa. Nature Clim Change 5, 815–822 (2015). https://doi.org/10.1038/nclimate2727

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