Hi,

The Mann–Kendall test is a non-parametric test used to detect trend

of a time series data (whether a set of data values is increasing over time or decreasing over time) and are used when the data do not normally distributed. So the null hypothesis is that there is no (monotonic) trend.

The Sen's slope is the non parametric estimator of the linear trend slope.

Beware, before utilizing the Mann–Kendall test and Sen's slope estimator, you need to remove serial correlation from the data (von Storch and Navarra 1999).

God luck,

Hamid

P values are used to test hypothesis, therefore, if the p value is greater than 0.05 it means that the result is not significant and the null hypothesis should be accepted. But if the p value is less than 0.05 the null hypothesis should be rejected