<p>The region of the Middle East and North Africa (MENA region) encompasses countries of the eastern Mediterranean, the Middle East, and North Africa, from Morocco in the West to the Islamic Republic of Iran in the East and from the Syrian Arab Republic in the North to the Republic of Yemen in the South. It is home to some 500 million inhabitants and is characterized by widely varied political and economic settings and a rich cultural heritage. Stark environmental gradients, as well as significant differences in the provision of ecosystem services, both East to West and South to North, are typical for the MENA Region.</p><p>Climate changes in the Mediterranean Basin, in general, and in the MENA countries, in particular, currently exceed global mean values significantly. Numerical model results indicate that this trend will continue in the near future and imply that the number of extreme summer temperatures and heatwaves may increase significantly over the coming decades. At the same time, a decrease in precipitation and a significantly longer dry season for most MENA countries than at present are anticipated. This leads to a significantly increased demand for water and energy. In addition, other factors further exacerbate these demands in the MENA, including the general economic development, extreme population growth and increasing urbanization, changes in lifestyle, shifting consumption patterns, inefficiencies in the use of resources that result from technical and managerial inadequacies and energy and water subsidies in several countries of the region to name but a few.</p><p>The impacts of climate change will be particularly severe in urban settings and large cities of the Mediterranean Basin and the MENA region. Cities will see an enhanced heat accumulation compared to the surrounding rural land due to heat-build-up in buildings, transportation infrastructure, and enhanced human activities. Reduced ventilation within cities exacerbates the warming, particularly during summer heatwaves. Consequently, additional, energy-intensive space cooling will be needed in order to maintain acceptable indoor conditions. With regard to water scarcity, the aforementioned decreases in precipitation will reduce available drinking water for city inhabitants and green spaces. This requires the provision of unconventional water sources, e.g., through desalination, which requires significant quantities of energy. Overall, climate change will exacerbate resource demand for water and energy, in general, and in urban settings, in particular.</p><p>However, the provision of water and energy are interrelated. In order to maintain water and energy security in the MENA region, these issues need therefore be considered holistically in the framework of the Water-Energy-Nexus (WEN).</p><p>The present paper aims to elucidate some of the interrelationships between water and energy resources and their provision and will briefly outline a few of the possible mitigation/adaptation options/strategies to reduce adverse impacts of climate change on the MENA region and its inhabitants.</p>
Genetic flow among olive populations within the Mediterranean basin
