Trend Analysis of the Monthly and Annual Air Temperatures in Port-Said City (Egypt)

Abstract

This study investigated variations in a long-term air temperature record in Port Said; to conclude the presence or absence of climate change in this important Egyptian city. The data collection spans 31 years, from 1991 to 2021. The research examined the homogeneity of the annual data, and the linear regression approach to specify the trend of air temperature variations throughout the study period. Moreover, the study investigated the trend significancy by using the Mann-Kendall test, the anomaly calculations and statistically specified the extreme air temperature events. Results revealed that the data were homogenous. Monthly mean air temperatures had increasing trends with varying rates, and the annual increasing trend had a rate of + 0.04°C/yr at 99% confidence level. A negative anomaly period existed only during the period 1991–1997, and as of 1998 the anomaly was always positive. The extreme air temperature times were precisely specified. Four extreme high and 12 extreme low monthly events were detected throughout the study period. The year 2010 (22.7°C) and the year 1991 (20.5°C) were determined as sole years of respectively extreme high and extreme low mean annual air temperatures. The research findings are regarded to be a trustworthy indicator of climate change in Port Said.