I have not tried to calculate R from records. I have read that from the USLE/RUSLE research, erosion rates (soil loss) reaches a maximum at 3 inches per hour. I don’t know why, but maybe a layer of water on the surface at that intensity dampens the energy. If one looks at the R map of the USA, you may note some areas with high rainfall as coastal Oregon have a substantially lower R value, that areas of the SE USA, which are exposed to a higher frequency of intense events from thunderstorms and tropical events from Gulf and Atlantic. You might look up our paper on Sediment from a Small Ephemeral Gully, and find that it was just a few events that episodically delivered sediment. I don’t know the extent that R values have been estimated across the world. If using the RUSLE, R is one of the several factors to include (K, s, SL, C, P). Interesting enough, Luna Leopold asked our class a question involving the dry SW USA, “Is there more erosion in wet or dry years?” His study showed more erosion in dry years due to the marked reduction in vegetation - cover. If you arrive at an estimate of R, see if you cannot find others who have estimated or used R factors in your area of interest.

Dear Dr. Alie Kamara I think, that should be acceptable.

However, I hope you considered the Kenetic energy as well in your derivation?

Additionally, you can try this R Package for calculation of rainfall erosivity factor

Best,

It can be suffitient. It depends on correlation coefficient and how many pluviographs for how large model area you have. You can get stastically significant correlation of R values and daily rainfalls even for 3 years data but regresion equation can differ according to used number of pluviographs or it can be different for several geographical locations of pluviographs. You can se some useful details about R factor in published papers on my profile. My recommendation for you: the correlation will be stronger for daily rainfall totals > 12.5 mm (or >/= 12.7 mm).