The absence of rainfall in Lebanon: upcoming water crisis?
By Giulia Del Sarto
Lebanon will face a water crisis this spring and summer due to unprecedented scarcity in rainfall. January 2014 – usually the rainiest month of the year – have witnessed an awkwardly sunny weather. Until January 21, rainfall rates in Lebanon had failed to reach the normal yearly average, according to meteorological figures at Beirut’s international airport. Rainfall in the capital should have been 440 millimeters at this time of year, but only 237.8 millimeters were recorded. In Central Bekaa, the average reached 128 millimeters, compared to an average of 435 in previous years. In the north, it reached 340.9 millimeters, compared to 454.
If precipitations fail to increase in February and March, a crisis of water scarcity will be inevitable.
Underground water needs to be refilled and replaced by rainfall and snow in order to meet residents’ needs, both in rural areas and in the municipalities.
The lack of precipitation, the decline in surface area covered in snow and the decrease of snow layers will inevitably lead to underground and surface water scarcity.
Indeed, consumers will have to rely on underground water to meet their needs given the lack of surface water but underground water resources will dry up quickly. Moreover, Syrian refugees – who represent around a quarter of the population – will make water demand increase. Supposing that their water consumption is the same as the indigenous population’s, the demand will increase by 25 percent.
Climate Change and Global Warming Effects
The drastic reduction in precipitation seems to be the result of climate change. According to the National Oceanic Atmospheric Administration’s calculations, 2013 tied for the world’s fourth warmest year on record. Comparison with LMS (Lebanese Meteorological Station) historical temperature records from the early 20th century indicates that the expected warming has no precedent. Rainfall is also projected to decrease by 10-20% by 2040 compared to the present. The climate will become hotter and drier and temperature extremes will intensify and the drought periods, over the whole country, will become longer.
Professor John Pomeroy, the Canada research chair in water resources and climate change at Saskatchewan University declared in 2011 that “The intensity of rainfall is getting greater but the time between rainfalls is also getting greater. This means that ironically we will have more rain but also more droughts.” That brings two different negative effects: erosion and floods – due to the fact that water comes too fast – and droughts and warming (existing climate models predict temperatures in Lebanon rising between 4 to 5°Celsius within the century) which will lead to the disappearing of the snowpack bringing about a devastating impact on Lebanon’s water reserves.
Temperature raise will have adverse impacts on rivers and groundwater recharge, especially that snow melt will occur in early spring, while the demand for irrigation water is especially high in the summer period. In addition, according to UNDP, snow will shift from 1,500 m to 1,700 m by 2050 and to 1,900 m by 2090, affecting the recharge of most springs. Extreme weather conditions will also manifest, experts predict that winter ﬂoods can increase up to 30%, and hot summer days and tropical nights can last at least two months longer. Droughts are predicted to occur 15 days to 1 month earlier, which will negatively affect the existing water shortage due to urbanization and population growth. The already dry regions (Bekaa, Hermel and the South) will be mostly affected.
The impact on agriculture is also worrisome: higher temperature, reduced precipitation and high evapotranspiration will decrease soil moisture and increase aridity, which will affect the overall agricultural yield of crops. Productivity is expected to decrease (especially for wheat tomatoes, cherries, apples and olives) and infestation of fungi and bacterial diseases will increase.