Spatio-temporal variability of sea surface temperature in the Algerian Sea (SW Mediterranean Sea), from 37 years of analyzed data

This study examines the spatial and temporal variability of sea surface temperature (SST) in the highly dynamic Algerian Sea (AS), focusing on six different regions. These areas were chosen for their typical meteorological and geomorphological characteristics. SST data from the last 37 years (1982-2018) were analyzed on a monthly, seasonal, and yearly time scale. The relationship between SST, precipitation, river discharge, and a few natural climatic indicators was investigated. The non -parametric Mann -Kendall test was used for trend analysis, and the Pettitt, Buishand, and Hubert tests were used to assess dataset homogeneity over time. Correlation between variables was examined. The findings showed a significant warming trend of 0.030 degrees C/ year across the entire AS from 1982 to 2018, with two notable breakpoints. In the western regions, the warming trend was divided into three distinct phases: the first from 1982 to 1994, the second from 1994 to 2010, and the third from 2010 to 2018. In the eastern regions, three phases were observed: 1982-1994, 1994-2014, and 2014-2018. This finding suggests that western waters warmed before eastern areas. In all regions, the summer season had the fastest warming rate, ranging from 5.2 to 5.9 E (-2) degrees C/year, followed by autumn, with rates ranging from 2.8 to 3.7 E (-2) degrees C/year. Spring and winter warming rates were relatively low, ranging from 2 to 3 E-2 degrees C/year and 1.1-1.6 E -2 degrees C/year, respectively. The results indicate a seasonal and annual correlation between SST and the El Nin o Southern Oscillation (ENSO), Western Mediterranean Oscillation (WeMo), North Atlantic Oscillation (NAO), and Mediterranean Oscillation (MO) modes during the study period.