Investigation of trends and variability in rainfall and temperature data in the Arid Arab region

Recently, the study of temperature and rainfall data on a global scale show the existence of significant trends, which are linked to the global warming phenomena. Studies also show that the variability of meteorological and hydrologic data can be attributed to some global phenomena such as the sunspot cycle and El-Niño/Southern oscillations, among others. In this paper, a number of temperature and rainfall data series in Egypt and the surrounding Arab countries are investigated for the existence of trends, their significance, and directions of change. Also, the variability in the characteristics of these time series and their relationship to global variations are studied. A number of new trend analysis techniques and modified statistical tests as well as improved spectral analysis methods are used.