Inducing Water Productivity from Snow Cover for Sustainable Water Management in Ibrahim River Basin, Lebanon
Talal Darwish *
National Council for Scientific Research, Remote Sensing Center, P.O. Box 11-8281, Beirut, Lebanon
Amin Shaban
National Council for Scientific Research, Remote Sensing Center, P.O. Box 11-8281, Beirut, Lebanon
Ivan Portoghese
Consiglio Nazionale delle Ricerche, IRSA – UOS di Bari, viale F. De Blasio 5, 70132 Bari, Italy
Michele Vurro
Consiglio Nazionale delle Ricerche, IRSA – UOS di Bari, viale F. De Blasio 5, 70132 Bari, Italy.
Roula Khadra
International Centre for Advanced Mediterranean Agronomic Studies, Bari Istituto Agronomico Mediterraneo (CIHEAM, IAM-Bar)i, via Ceglie 9, 70010 Valenzano (BA), Italy.
Sagedah Saqallah
International Centre for Advanced Mediterranean Agronomic Studies, Bari Istituto Agronomico Mediterraneo (CIHEAM, IAM-Bar)i, via Ceglie 9, 70010 Valenzano (BA), Italy
Laurent Drapeau
Centre for Space Studies of the Biosphere, CESBIO, 18Av. Edouard Belin (2801 BPI) 31401 Toulousecedex9, Toulouse, France.
Simon Gascoin
Centre for Space Studies of the Biosphere, CESBIO, 18Av. Edouard Belin (2801 BPI) 31401 Toulousecedex9, Toulouse, France.
Nabil Amacha
Litani River Authority, Beirut, Lebanon
*Author to whom correspondence should be addressed.
Abstract
The aim of this paper is to explore the effects and linkages between snow cover areas, distribution, probability and measured water discharge along east Mediterranean coastal watershed using moderate-resolution satellite images (MODIS-Terra). The Nahr Ibrahim River is a typical Lebanese watershed with an area of 326 km2 stretching between the sea and mountainous terrain to the east. The largest snow cover often exists in January-February with snow-free conditions between June and November. Image analysis enabled to analyze the temporal variability of the mean and maximum monthly areas of snow cover between 2000 and 2013. Snow cover dynamics were compared with the discharge from main springs (Afqa and Rouaiss) feeding the river and the probability of snow cover was estimated. The mean monthly snow cover, snow melting rates and springs discharge were found to be in direct relationship. In addition, the measured water discharge at the river mouth was found to be higher than the discharge of the two main feeding springs. This indicates a contribution of groundwater to the stream flow, which is again in direct connection with snow melting at the upper bordering slopes and probably from neighboring watersheds. Considering the characteristics of the mountainous rocks (i.e. Sinkholes, fissured and karstified limestone), the pedo-climatic and land cover conditions affect the hydrological regime which is directly responding to the area and temporal distribution of snow cover, which appears after two months from snowing events. This is reflected on water productivity and related disciplines (Agricultural yield, floods). This study highlights the potential of satellite snow detection over the watershed to estimate snow cover duration curve, forecast the stream flow regime and volume for better water management and flood risk preparedness.
Keywords: Snow melt, springs, groundwater, MODIS-Terra, east mediterranean