BY Dr Osama Gazal
Water scarcity and limited water resources combine in Jordan with other driving forces and pressures which can be classified according to Gazal’s DPSIR framework (2021) into three main pressures: climate change, agricultural activities and refugees. In this article, climate change and the increasing frequency of drought episodes have been briefly explained.
Gazal 2021 studied daily climatological data from 346 weather stations to summarize the climatological parameters of Jordan. Jordan’s annual regional precipitation has a decreasing trend, with an average of -0.674 mm / year estimated annual precipitation from 1937 to 2019 by Gazal (2021). The long area of annual precipitation over the past 82 years is average P = 92.2 mm). Gazal 2021 has shown that the rate of drought at which they occur is expected to increase every 25 years, with normal drought averaging 2-3 years and severe drought every 8-11 years. These droughts are increasing and other adverse effects of climate change in Jordan are expected to further reduce water availability by 15-20%.
Recent in-depth studies by the United Nations Development Program (UNDP, 2017) (Development of a high-resolution hydro-climatic model to promote cooperation on water management between the Palestinian, Israeli and Jordanian authorities in the ‘water) have shown that the forecast water situation for Jordan is problematic. predicted taking into account both RCP4.5 and 8.5 scenarios. The study’s RCP 4.5 predicted a median decrease of 14 mm (-7%) for 2021-2050 and of 22 mm (-11%) for 2071-2100. One of the main conclusions of this previous study is that even in the absence of a strong trend of precipitation, the combination of the increase in temperature and evapotranspiration clearly shows that the situation of the management of the Water will worsen, with increasing water demand and stress in Jordan.
Jordan is divided into three climatic zones according to the special variation of annual rainfall, according to the Jordanian Ministry of Water and Irrigation (MWI), these three very different climatic zones are the Jordan Valley, the Plateau of mountain heights, and the eastern desert or Badia region (MWI & BGR 2018). The climate of the Jordan Valley is arid to semi-arid, with a hot, dry summer and a warm winter. Average annual precipitation is very low, generally less than 200 mm / year. The northern and central parts of the Jordan Mountain plateau are characterized by a Mediterranean climate with hot and dry summers, cool and wet winters and two short transition seasons. This climatic zone has the highest rainfall levels in Jordan. While the annual average precipitation in the Eastern Desert and the Badia area is less than 100 mm / year.
According to the precipitation zones adopted by MWI (2016), modified by Gazal (2021), there are five zones of precipitation (desert, arid, marginal, semi-arid, semi-humid) each zone represents (71.5%, 22 , 27%, 2.25%, 3.27%, 0.68% respectively) of the total area of the country, each zone receives an average annual precipitation of approximately (less than 100 mm, 100-200 mm, 200- 300mm, 300-500mm, 500-650mm respectively). Only the semi-humid zone, which is about 620 km2 and represents 0.68% of the country’s surface area, can receive 500-650 mm / year.
Therefore, increased efforts to adapt to the effects of climate change and the increasing period of drought are needed, along with concerted efforts to increase water harvesting projects and make optimal use of the rainfall received. coupled with an increase in studies to demonstrate the feasibility of increasing the storage capacity of existing dams or of expanding it by establishing small dams. But the desalination of seawater and brackish groundwater is the future solution to tackle the water crisis in Jordan.