towards “ultra-extreme” heat waves in the Middle East and North Africa

Spread the love

The heat waves that threaten to hit the European continent if nothing is done to limit the warming pale in comparison to those announced in North Africa and the Middle East. Indeed, the results of a study recently published in the journal Climate and Atmospheric Science indicate that maximum temperatures could reach values ​​above 56 ° C, or even exceed 60 ° C in some highly urbanized localities.

Given the intensity of these episodes, the researchers speak of heat waves ultra-extreme. Lasting up to a few weeks, they should occur exclusively in the second half of the century. These are then more than 600 million people that would be regularly exposed. However, at such temperatures, the human organism, like that of very many animals, is no longer easily able to regulate its metabolism and thus depends heavily on artificial cooling (air conditioning, etc.). In addition to the implications for agriculture, these heat waves therefore constitute a very serious threat to human health and the environment.

A study specifically focused on the field MENA

To carry out their study, the scientists used a set of numerical simulations from different climate models. The objective being to analyze the way in which the heat waves evolve on the field MENA (Middle East and North Africa) when the global climate heats up sharply.

Evolution of the heat wave amplitude index according to different models (a). Percentages of the region MENA exposed to different types of heat waves each year (b). The timescale runs from 1951 to 2100. Finally, remember that in the scenario studied, global warming continues unhindered. Credits: George Zittis et al. 2021.

The scientific community that deals with regional climate modeling is mainly concentrated in Europe and North America, and there is still little interest and funding for studying the impacts of climate change in the Mediterranean and North African region »Explains Paola Mercogliano, director of REHMI who did not directly participate in the work. ” To have such an important and detailed study on this area, which is still poor in data and scientific knowledge on climate change, is a great success for us. “.

Heat waves and climate: a double penalty

Finally, the image which emerges concretizes a double problem. On the one hand, global warming, which should be limited as best as possible to prevent these countries from being confronted with particularly dangerous heat waves. On the other hand, urbanization which makes populations even more sensitive to hot extremes due tourban heat island. “ The vast majority of the exposed population (> 90%) is expected to live in urban centers, which are expected to face socially disruptive weather conditions »Notes the study in its summary.

Population (in millions of people) exposed to different types of hot extremes (color code). The solid lines represent the affected population. The dotted lines, the share of the population in urban areas. In black, the expected evolution of the total population in the area MENA. Credits: George Zittis et al. 2021.

With the new data obtained, political and social decisions that will dictate climate mitigation and adaptation measures can be taken in a better scientific context. Thus, the growing interest of the community of modellers for the domain MENA will allow better ownership and management of the climate challenge, which promises to be particularly difficult in these regions of the world.


Source link