# Spatial-Temporal Variability of Future Rainfall Erosivity and Its Impact on Soil Loss Risk in Kenya
## 4 Discussion
The entire croplands in the country were estimated to have the highest baseline average annual soil loss rate (17.86 t ha\({}^{-1}\) yr\({}^{-1}\)), which is comparable to the results reported by [PERSON] et al. [14]. Most of the croplands are found within areas of steep terrain and highly erodible soils. [PERSON] and [PERSON] [86] further attributed these high rates to poor farming practices, where farmers leave the soil bare for extended periods, thus enhancing soil erosion, especially during extreme weather conditions. The total baseline soil erosion rate estimated in Kenya (4.76 t ha\({}^{-1}\) yr\({}^{-1}\)) was slightly less than in most regions of the globe: 39.2 t ha\({}^{-1}\) yr\({}^{-1}\) for Rwanda [87], 0.7-17.9 t ha\({}^{-1}\) yr\({}^{-1}\) for Europe, 10.8-146 t ha\({}^{-1}\) yr\({}^{-1}\) for Africa [84] and 0-273 t ha\({}^{-1}\) yr\({}^{-1}\) for Nepal [81]. In addition, Kenya's erosion rate estimates were below the tolerable limit of 25 t ha\({}^{-1}\) yr\({}^{-1}\) for environments with young mountains topography, as suggested by [PERSON] [84]. The spatial pattern of the mean annual rainfall figure had a high degree of similarity with other rainfall distribution maps reported at both the continental and regional scales [88]. [PERSON] (2017) [89] largely attributed the aridity of the northeastern parts of Kenya to the divergence of the Somali jet that drives the Indian Monsoon. Both global and regional phenomena contribute to the heterogeneous nature of Kenya's rainfall pattern. These include the seasonal migration of the ITCZ that accounts for the EA's seasonal rainfall variability [97], solar flux fluctuations and global sea surface temperatures (SST) in the Atlantic Ocean, as well as the Indian and Pacific Ocean anomalies that are linked to the Indian Ocean Dipole (IOD) and the El Nino Southern Oscillation (ENSO), respectively [98]. Other factors, including proximity to large inland lakes and orographic effects, greatly influence moisture exchanges, thus contributing to variable local rainfall patterns [89]. Similar to our results, reference [99] also reported rainfall erosivity values greater than 5000 MJ mm ha\({}^{-1}\) h\({}^{-1}\) yr\({}^{-1}\) in the highland areas of Kenya as well as over the Lake Victoria region [18]. Furthermore, the rainfall erosivity distribution map showed a consistent pattern when compared to previous erosivity maps reported for Kenya. As presented in other previous regional research [50], this study predicted the soil erosion in Kenya with respect to changes in the climatic factor (rainfall erosivity) within the RUSLE model, while holding the other factors constant. Our results indicate that the overall future soil loss rate is projected to increase significantly for both time slices, due \begin{table}
\begin{tabular}{c c c c} \hline
**Location** & **Climate** & **\(R\) Factor** & **References** & **This Study** \\ \hline Kianjuki catchment & Aw & 8527 & [48] & 8784.5 \\ Katumani & Aw & 1644 & [67] & 1621.1 \\ Eldoret & Aw & 3795 & [67] & 4467.0 \\ Taita Taveta Voi & Bsh & 2774 & [67] & 2058.2 \\ Narok & Csb & 2621 & [67] & 3067.2 \\ \hline \end{tabular}
\end{table} 
Table 17: Past literature \(R\) factor values (MJ mm ha\({}^{-1}\) h\({}^{-1}\) y\({}^{-1}\)) based on multiple years \(El_{30}\) calculations in Kenya. \begin{table}
\begin{tabular}{c c c c} \hline
**Location** & **Climate** & **Observed MASLR** & **References** \\ \hline Lake Baringo sub-basin & Aw & 16–96 & [90] \\ Upper Ewaso Ng\({}^{\prime}\)iro sub-basin & Aw & 0–51.3 & [45] \\ Machakos, Kenya & Aw & 16–36 & [91] \\ Athi basin area & Bsh & 15 & [92] \\ Embu & Am & 11 & [93] \\ Machakos & Am & 2–60 & [94] \\ Embu & Am & 16–118 & [86] \\ Tharaka Nithi & Am & 1–2 & [95] \\ Kabete & Cfb & 2–6 & [96] \\ \hline \end{tabular}
\end{table} 
Table 18: Mean soil erosion rates (t ha\({}^{-1}\) yr\({}^{-1}\)) from previous plot studies within Kenya. to the increased erosive power of precipitation.