Extreme Climate Changes in the MENA Region: Their Impacts and Effective Adaptation Strategies

<p>Countries of the Middle East and North Africa (MENA Region) are plagued by extremely hot, dry summers and extended warm spells, and are known as a &#8220;climate change hot spot&#8221;. Results of numerical climate models project heat waves lasting up to 90 days with temperatures of more than 50&#176;C for the late 21^st century. Since the region is heavily urbanized, enhanced warming in larger cities leads to outdoor conditions that become unbearable and pose extreme health risks to a large fraction of the human population. Decreases in precipitation are enhanced through heat-related processes and result in extreme water scarcity.</p> <p>Such conditions need to be addressed by effective and well-founded adaptation strategies in the MENA region. With regard to the provision of potable water, desalination of sea- and brackish water becomes an almost unavoidable requirement for coastal cities. In order to maintain food security in water-scarce agricultural areas, innovative irrigation technologies in combination with smart agricultural practices need to be practiced. Extreme outdoor and indoor temperatures in urban settings require substantial space cooling through electrically driven air conditioners. In addition and preferentially, new buildings should be erected following strict rules for low to zero-energy houses. Existing buildings should undergo significant retrofitting efforts that reduce heat intake and minimize the use of air conditioning. In addition, and already practiced in some of the MENA countries, cities will have to provide &#8220;cooling spaces&#8221; for those inhabitants that live in poorly insulated buildings and cannot afford costly space cooling.</p> <p>All of these measures require substantial amounts of electrical energy. This applies in particular to the desalination process, which consumes ca. 4&#160;kWh/m³ of potable water. Assuming a need of ca. 100&#160;lpd (lpd=liters per person per day; 100&#160;lpd=0,1&#160;m³). In a city of, e.g., 250&#160;000 inhabitants, 25&#160;000&#160;m³ of potable water is needed, which requires 100 000 kWh (100 MWh) of electricity per day or 36 500 MWh (36,5 GWh) per year.</p> <p>The electrical energy required for space cooling amounts to ca. 0,15&#160;kW/m² of indoor living space. Assuming a daily cooling load of 10&#160;hours in a typical house/apartment will translate into 1,5&#160;kWh/m²/d. Given a nominal requirement of indoor space of ca. 25&#160;m²/person results in an energy need of 37,5 kWh/person/d. Assuming the above-described conditions of future extreme urban warming space cooling will be required for about 8 months (240 days) by 70% of a city&#8217;s population of 250 000 (175 000 persons), we derive at an annual electrical energy need of 1 575 GWh or ca. 1,6 TWh.</p> <p>Given such numbers, it is not surprising that cities currently account for about 80% of energy globally and 75% of greenhouse gas emissions. Given the prospects of extreme climate change in the MENA region, this number is likely to rise. This underlines the urgent need to employ alternative renewable energy sources to satisfy demand. Moreover, it becomes increasingly apparent that effective adaptation strategies that reduce the risks to human communities and natural ecosystems rely on innovative and effective strategies in the framework of a Water-, Energy- and Food-Nexus.</p>