TITLE:
Use of the Daily Temperatures in Estimating the Climate Change Indices for 1985-2023 in Saudi Arabia
AUTHORS:
Salah Abdulmohsin Alshammar
KEYWORDS:
Maximum Daily Temperatures, Minimum Daily Temperature, Homogeneity Test, Variations, Trends, T-Student Test, Mann-Kendall Test, Saudi Arabia
JOURNAL NAME:
American Journal of Climate Change,
Vol.15 No.1,
January
30,
2026
ABSTRACT: Climate change poses significant economic, social, political and environmental challenges, with impacts more effective on dry areas. This research presents an analysis of daily temperatures used in determining the trends of maximum and minimum temperatures (Tx and Tm). The data was collected from NCM (National Center of Meteorology) for 39 years (1985-2023). This study addresses data by analyzing the variability by using the coefficient of variation (CV), homogeneity by applying three tests (Pettit, SNHT and Buishand). The Semi-average and Man-Kendall methods were used to analyze long-term trends in temperature in 10 regions of Saudi Arabia from 1985 to 2023 using Mann-Kendall test. The results of (Tx) frequency analysis showed that the temperature from 10˚C to 20˚C is the main class at Abha, from 15˚C to 25˚C at Riyadh and Yanbu, from 20˚C to 30˚C at seven stations during 1985-2023. The (Tm) from 20˚C to 30˚C is the main class at Rafha and Al Hassa, from 15˚C to 25˚C at Al Jouf and Al Bahah, and the class (10˚C - 20˚C) at Qurayate and Abha. The spatial variability reveals that the maximum Temperature (Tx) higher than 30˚C appears in Al Hassa, Yanbu, Riyadh, Rafha and Tabouk, while the (Tx) lower than the 30˚C appears at the northern stations and Assir. The lower minimum temperatures (Tm) are greater than 20˚C in Eastern Province) and (Western coast), but the minimum temperatures ranged between 15˚C and 18˚C were recorded in different regions. From Pettit’s test, the computed p-value of maximum daily temperatures (Tx) is greater than the significant level (alpha: 0.05) at the total of stations, except Turayf. The results of SNHT test also consistent with the results of Pettit’s test and indicate the homogeneous data at all stations. The results of Buishand’s test confirmed the results of SNHT test. The results of the T-student test revealed three and seven insignificant increased trends and seven insignificant decreased trends of maximum temperatures, respectively. The results of the semi-averages also showed four and three insignificant decreased and increased trends of the minimum daily temperature, respectively. However, the minimum temperatures showed the significant and increased trend in Abha, Al-Ahsa and Tabuk. This study presents the spatial variation of daily temperatures using the statistical tests for analyzing the data recorded during the period 1985-2023. The integrated employment of the statistical methods and gives more accurate results about climate change indicators over Saudi Arabia.