Movement of the tropical rain belt (TRB) is arguably the most important determinant of regional climate in Africa: its average seasonal position defines humidity or aridity and fluctuations lead to flooding or drought. Accurate simulation of the TRB is thus essential to build confidence in future projections of regional African rainfall. However it has been shown that previous generations of climate models have shown significant problems with fundamental aspects of TRB seasonality, particularly over East Africa (Tierney et al. 2015). Here we propose to evaluate the representation of the TRB in CMIP6 models. Existing code is available (Nikulin and Hewitson 2019), which can be used to swiftly assess representation of key attributes of the TRB. From this a more in-depth focus on regional aspects of TRB variability, such as the TRB-influence on Sahel summer rainfall, and its representation in models can be explored, along with future projections.

• Nikulin, G. and Hewitson, B., 2019. A simple set of indices describing the Tropical Rain Belt over central and southern Africa. Atmospheric Science Letters, 20(12), p.e946.
• Tierney, J.E., Ummenhofer, C.C. and Demenocal, P.B., 2015. Past and future rainfall in the Horn of Africa. Science advances, 1(9), p.e1500682.