The variability and changes of precipitation in arid and semi-arid zones of Algeria (Ghardaia, Ouargla, Biskra and Laghouat) From 1969-2016

Abstract

This study investigates the impact of climate change on extreme precipitation indicators in the arid and semi-arid regions of Algeria, specifically Ghardaïa, Ouargla, Laghouat, and Biskra, during the period 1969-2016. The research utilizes innovative trend analysis (ITA) and change point detection methods to analyze and calculate precipitation trends and indices. The results of the ITA and change point methods are compared, and 10 precipitation indices for extreme events are computed. The findings reveal increasing trends in mean precipitation for most stations, as well as varying trends in extreme daily precipitation events, often associated with flooding. However, no significant decreasing trend in precipitation is observed across all the analyzed stations. The change point detection analysis indicates that only two stations (Ghardaia and Biskra) exhibit three change points, signifying shifts in either station data or climate conditions. These findings provide insights into the behavior of precipitation data series and the specific dates of occurrence for these shifts. Notably, one station does not show any change point detection. This research aims to contribute to the understanding of climate change impacts in Algeria's arid and semi-arid regions and enhance preparedness for future extreme precipitation events