The rise in the level of the Mediterranean will displace 20 million people

The Mediterranean and its vulnerability to the threats of climate change deserved their own space at the beginning of the second week of the negotiations taking place in Baku (Azerbaijan) on the occasion of the 29th Climate Summit. The MedECC expert group, an independent network of scientists providing scientific assessments, together with the Union for the Mediterranean (UfM), representing the countries of the Mare Nostrum basin, presented a study that compiles the latest available data on the dangers that will alter the future of what is today the main tourist destination in the world. Heat and rising sea levels will be the most serious problems that will require a greater adaptation effort.

Coordinated by the professor of Applied Physics at the University of Barcelona, ​​Carmen Llasat, 55 authors from 17 countries have exposed all the threats that justify the classification of “critical focus of global warming” that this region of the world receives.

Inés Durate, head of energy at the UfM, was clear during the press conference offered: “It is time to understand that the Mediterranean, as we know it, could cease to exist if our efforts to combat climate change continue to be insufficient” .

The study presented analyzes each future threat taking as a starting point the First Mediterranean Assessment Report (MAR1), the first of a regional scientific nature on climate change and environmental degradation carried out in this region, and provides adaptation solutions for each of them.

One more meter in 2100

The floods resulting from the rise in sea level during this century are perhaps the factor that will require greater adaptation measures for the population living in the Mediterranean basin.

As long as warming trends, emissions and the rate of rise of the planet’s ocean levels continue as they are, MedECC experts estimate that up to 20 million people across the region could be permanently displaced by the end of this century. .

Currently, a third of the population of the Mediterranean region lives very close to the sea and depends on its infrastructure and economic activities, which are also located in these areas. Far from decreasing, forecasts suggest that the coastal population will increase more rapidly than those in the interior of countries, which will leave a greater number of people exposed to the dangers of climate change.

This trend will put transportation networks or cultural heritage at “high risk.” Without going any further, the aforementioned work recalls that the Mediterranean region already hosts three of the twenty airports in the world at greatest risk from coastal flooding.

The current rate of sea level rise in the Mediterranean is 2.8 millimeters per year. This is double the 20th century average. Looking at the end of the 21st century, projections suggest that the average sea level could rise by one meter. “The Mediterranean coast is one of the regions in the world most likely to suffer severe flooding, the impact of which will be aggravated by climate change and population growth on the coast,” the international work states.

10% flooding

Extreme sea level events, which occur once every 100 years, are likely to increase in frequency by “at least” 10% by 2050 and by 22% by 2100, under a scenario of greenhouse gas emissions. greenhouse effect -responsible for global warming- intermediate.

The extremes will be accentuated. Torrential rains, such as those experienced during the danas this autumn, will increase in some regions of the northern Mediterranean, but the balance of global rainfall for the year will be negative, paradoxically accentuating droughts.

‘Both coastal flood protection and erosion management often rely on expensive engineering solutions and generally do not take into account future values ​​of sea level rise, which could imply that its effectiveness would be limited in the long term,” the experts warn when assessing how to adapt to the reality they draw for the year 2100.

This rise in water is closely linked to the increasingly high temperatures of the sea. If marine heat waves have already increased in frequency and duration during the last decades by 40% and 15% respectively, projections indicate that this progression will increase during the century.

Double the amount of plastic accumulated

This leads to an increase in carbon emissions (because the seas become less efficient at ‘cleaning’ the air of CO2 the higher their temperature) and, on the other hand, will favor the appearance of invasive species, which will have socioeconomic and ecological consequences. . Corals, sponges and mollusks have experienced massive deaths due to water temperatures, a phenomenon that will continue to worsen in the future.

Added to this is that it is one of the areas most contaminated by plastics in the world. These represent up to 82% of visible litter, 95-100% of total floating marine debris and more than 50% of that found on the sea floor. By 2040, it is estimated that plastic discharges into the sea will double if the production of this material continues to increase at a rate of 4% and if its management as waste does not undergo a radical improvement.

The availability of fresh water in the region will also be conditioned by changes in global temperatures. While the world is heading towards global warming of 3º Celsius above the average temperatures that existed on the planet before the pre-industrial era, the speed at which this phenomenon is happening in the Mediterranean is much greater and could be destined to exceed 5.5º Celsius of warming at the end of the 21st century.

Less fresh water

So far, the average temperature has already increased by more than 1.5º; In 2050 it is expected to rise between 2.3º and 3.6º if high emissions continue as before. “This flood will be especially high in summer, with maximum temperatures that can reach more than 7 °C above those usual at the beginning of the last century, which entails, among other things, very serious impacts on health,” the experts recalled. today in Baku, during his appearance.

In this context, and as global temperature increases, the limits will become increasingly strict and resources such as conventional freshwater will require greater and better adaptation measures.

“The Mediterranean region is facing notable spikes in water demand, a phenomenon that is expected to intensify in the coming years due to climate change, agricultural practices, and increasing population and tourism in coastal areas,” conclude the authors of the work.