Investigation of trend analysis of monthly total precipitation by an innovative method

The purpose of this study is to detect possible trend in monthly total precipitation rate on the basis of Mann-Kendall (MK) and a new method recently proposed by Sen trend tests. The new method is used for trend analysis of monthly total precipitation data recorded at Samsun, Trabzon, Ankara, Yozgat, Adana, and Antalya provinces in Turkey. For comparison purposes, the well-known MK trend test is also applied to the same data. According to the MK trend test, Samsun and Trabzon generally have statistically significant increasing trend. There is no statistically significant trend (trendless time series) for Ankara, Yozgat, and Adana provinces. While the February month of Antalya shows statistically significant decreasing trend, April month of Antalya shows statistically significant increasing trend. According to the Sen's trend test, peak and low values of monthly total precipitation of the six provinces show different trends (increasing, decreasing, or trendless time series) from the MK trend test. The study shows that the Sen method could be successfully used in evaluation of peak and low values of data for trend analysis of monthly total precipitation variable.