Abstract: Long-term temperature and precipitation trends are two of the major determinants of climate
variability at geographic scale. This study aims to determine past trends in climatic parameters in
different regions of Benin. Six stations throughout Benin provided daily records of precipitation,
potential evapotranspiration, minimum and maximum temperatures. Those records were used for
the detection of probable trends. Time series data (1960-2016) of mean daily maximum and
minimum temperature, mean daily precipitation and potential evapotranspiration were analyzed.
Descriptive statistics, graphs and test of comparison were used in order to demonstrate possible
trends or differences. The results indicate that the minimum and maximum temperatures have
increased at all region of Benin. Likewise, precipitation during the same period revealed a
decreasing trend. In addition, the annual precipitation analysis showed disparate coefficients of
variation according to the stations explaining the abnormal distribution with large discrepancies
among years. The comparison of the mean state of the minimum and maximum temperatures
between the periods 1960-1988 and 1989-2016 exhibited a significant difference at five stations.
About potential evapotranspiration, the mean difference indicated the shortage through five
stations, but significant only at one station. However, there was no difference between the two
periods with respect to average annual precipitation. |