Quantitative analysis of spatial variability of rainfall in the Green Mountain region of Libya

Abstract

The Green Mountain region is of great importance in Libya, as desert and semi-desert lands cover an area exceeding 90% of the country's area. The Green Mountain region is the only exception to this critical geographical environment, as it receives the highest rainfall rates and is characterized by evergreen vegetation cover, which has made it an area of ​​dense population, agricultural, and pastoral settlement.
Rainfall is the most significant precipitation in the Green Mountain region. Since the region lies within the Mediterranean basin, which is influenced by low-pressure systems, cyclonic rain during the winter is the most important type of precipitation in the area. It should be noted that the rugged terrain and elevation of the region, exceeding 850 meters, impede the movement of moisture-laden air. In areas perpendicular to the windward slopes, the air rises and cools itself (aliabatic cooling) to the dew point, causing condensation and subsequent precipitation. Consequently, rainfall in the study region is orographically cyclonic in mountainous areas such as Al Marj and Shahat. However, in cases of atmospheric instability,
As in some situations accompanying the passage of cold air masses and Khamsin depressions in the spring and autumn seasons, the air becomes in an unstable equilibrium, which causes rainfall, usually heavy, accompanied by lightning and thunder, especially in the higher parts of the region.