TITLE:
Spatio-Temporal Variation in Rainfall Erosivity over Jordan Using Annual and Seasonal Precipitation
AUTHORS:
Y. Farhan, S. Alnawaiseh
KEYWORDS:
Rainfall Erosivity, Regression Models, Pearson Correlation, Annual and Seasonal Precipitation, Soil Erosion
JOURNAL NAME:
Natural Resources,
Vol.9 No.6,
June
27,
2018
ABSTRACT:
The objective of this research is
to estimate the annual and seasonal rainfall erosivity over Jordan based on
three different regression models. Readily available annual and seasonal
precipitation data with long records (40 - 53 years) pertaining to 40 weather stations were utilized to estimate
rainfall erosivity. The spatial distribution of rainfall erosivity over Jordan
is controlled largely by morphological (relief) and climatic factors. The lowest R-values
(28 MJ mm.ha-1.h-1.yr-1) are found in the arid zone, where the average annual rainfall is below
100 mm, whereas the highest R-values
are found in the northern highlands (505 MJ mm.ha-1.h-1.yr-1) where the
average annual rainfall approaches 650 mm. The correlation between annual and
seasonal precipitation (mm) and annual erosivity exhibits a very strong relationship (R varies from 0.964 to 1.0,
and all correlations are significant at 0.01 level [2-tailed test]). Moderate positive correlations were achieved between
latitude (N) and the mean annual/seasonal precipitation (R ranges from 0.407 to 0.642, and all correlations are significant at 0.01 level
[2-tailed test]). Spatial differences observed in erosivity, afforded a
substantial source of information and maps for predicting erosion in Jordan.
According to the present analysis, two parameters proved to be useful to
predict rainfall erosivity on a national level. These parameters are the average annual precipitation, and latitude.