Abstract
The Intergovernmental Panel on Climate Change (IPCC) provides a comprehensive review of the potential impacts on the hydrological variables of the man induced climate changes. It states that such changes will likely increase runoff in the higher latitude regions because of increased precipitation; also, the flood frequency is expected to change in some locations and the severity of drought events could also increase as a result of the changes both in precipitation and evaporation. Observations show that changes are occurring in the amount, intensity, frequency and type of precipitation. The frequency of extreme temperatures during the summer is likely to be higher. The Mann-Kendall test coupled with the Sen's slope was applied to identify the significant trends, positive or negative trend and the magnitude of those trends. The results achieved for rainfall revealed more frequent significant decreasing trends in Syria in the last 19 years.