 |
| (source) |
Under a 'business-as-usual' scenario, a recent study suggests that the region around the Arabian Gulf in the Middle East could become inhospitable for human life by the year 2100. To define a threshold to mark the climatic conditions tolerable by a fit human, Pal and Eltahir (2015) used a 'wet-bulb temperature' measure. This is a combination of temperature and humidity which is used to define the survivability of humans under certain climatic conditions. It is believed that the fittest human could last for up to six hours in a wet-bulb temperature of 35°C. The recent study published in Nature used an ensemble of high-resolution climate models to project future wet-bulb temperatures and found a specific regional hotpot in the region of the Middle East (figure 1). In July 2015, temperatures reached 34.6°C in Bandar-e Mahshahr, Iran for around an hour, extremely close to the 35°C wet-bulb temperature threshold identified as being fit for human survival. As the global surface temperatures continue to increase into the future, high evaporation rates from the Persian Gulf will increase humidity across the region. Furthermore, it is a region of low elevation and clear skies, conditions which makes the Middle East a hotspot for extreme conditions. Under the 'business-as-usual' IPCC scenario, this study suggests that the Middle East could see the 35°C threshold exceeded by 2100, making the region inhospitable for human life and driving major migration of people from the region.
This is a region with an ancient history which supports some of the world's earliest civilizations in Mesopotamia and the Fertile Crescent. It is the birthplace of many religions including Christianity, Islam and Judaism and a diversity of cultures and societies. Today, the region supports many of the world's major cities including Cairo (Egypt), Istanbul (Turkey), and Baghdad (Iraq). This study shows how the impacts of future climate change could have disastrous consequence for the societies inhabiting the region by 2100 by increasing threat to water and food security, driving a substantial rise in climate refugees from this region and a significant change to the world's demography.
 |
| Figure 1: Spatial distribution of extreme wet-bulb temperatures (a, b, c) and extreme temperature (d, e, f) for each historical GHG concentrations (a, d) and for representative concentration pathway RCP4.5 (b, e) and RCP8.5 (c, f) (source). |