Impact of Climate Change on Water Resources of Lebanon: Indications of Hydrological Droughts

Abstract

As a global meteorological process, change in climate conditions has become a serious topic that many researchers work on. However, data availability is still the major problem to analyze this process. Lebanon, as a Mediterranean region is influenced by climate change, which is viewed not only from fluctuation in the climatic elements, but also from its influence on the regime of water resources. These resources show an abrupt volumetric decrease in water supply, the so-called „hydrologic drought“. Thus accusation of water shortage has become a national issue. The study of this phenomenon is tackled through analyzing different indices of surface and subsurface water, thus comparing different records on graphical illustrations and numeric values. Results of this application in Lebanon revealed an obvious decline in the amount of available water. This decline shows a variance between different sources. However, those which are not in a direct touch with human, like precipitation and snow cover, are less influenced and a decrease of 12-16 % was resulted. These two elements directly represent the climate impact on water inputs. While, this percentage gets higher in the case of rivers and groundwater, in which their decrease ranges between 23-29 %. This adds the human interference to the climatic conditions, which is due to over exploitation form groundwater and rivers. Moreover, the number of springs and their discharge as well as the number of local reservoirs exhibits the most excessive influence, Consequently, it was reduced to 43 % and 79 % for the springs and local reservoirs; respectively. This high percentage is attributed to the dependence of human on these two sources. The obtained results in this study are quite alarming and expose a dramatic exceed in the level of hydrologic drought in Lebanon that would be worth taking decision as soon as possible to water conserve by following a wise-use of water resources.