In this study, twenty one of the CMIP5 models that have precipitation available for both the historical and AMIP experiments are used.  Their names are listed in Fig. \ref{fig:individual} and Fig. \ref{fig:scatter}. Only one run is chosen from each model in the calculation of the multimodel mean and other statistics across these models. As most models cover only the period before 2005 for the historical runs, the base period we choose to calculate climatology for both observations and simulations is 1979--2005 except that for the TRMM daily precipitation data, where 1998--2005 is used instead. In this study, we focus on the land areas of East Africa (30$^{\circ}$E-52$^{\circ}$E and 10$^{\circ}$S-12$^{\circ}$N) that show a bimodal rainfall annual cycle and an arid/semi-arid annual mean climatology by applying the following criteria to the GPCC precipitation dataset: 1) precipitation rate in March--May greater than both seasons of January--February and June--September; 2) annual mean precipitation rate less than 2 mm day$^{-1}$. The first criterion follows \citet{Yang_2015} to exclude the monsoonal areas with a single rainfall peak in local summer and thus isolates the bimodal annual cycle region.  The second criterion is added here to exclude the active equatorial convection areas where there are also two rainy seasons but  the annual mean rainfall is much larger than in the arid/semi-arid areas.  The resulting areas over East Africa are shown as gray grids in the mini panel of Fig. \ref{fig:boxplotAmip}. Area average over East Africa in this study is only applied to these grids unless otherwise stated.