[LUM#2] Homo Mediterraneus condemned to evolution

[LUM Magazine] - Published on April 12, 2016 in Science-Society

What about man? What is the impact on populations, societies and economies? Zoom in on a Mediterranean area threatened with boiling over.

There's nothing more difficult than drawing a precise picture of the fate of human societies," explains Eric Servat, Director of the Observatoire de Research Méditerranéen de l'Environnement (OSU OREME). But what do we know with a reasonable minimum of probability? Firstly, the Mediterranean climate will be increasingly unstable. " This virtually closed environment, where average temperatures are expected to rise by 2 to 4 degrees by 2100, behaves like a pressure cooker when heated. The result: severe weather instability throughout the region. And floods: they already account for a third of all natural disasters, and more than half of all fatalities.

Water at the heart of concerns

Longer dry spells and wetter winters will not be enough to compensate: overall, the annual precipitation deficit in the Mediterranean is predicted to be between 5 and 30%. A catastrophe for many regions on the southern rim and in the Middle East, already below the critical threshold of "water stress". A situation exacerbated by the growth and concentration of populations...

" Before the middle of this century, two-thirds of humanity will be living in coastal areas, in the broadest sense of the term. With increased pressure on local resources, and highly concentrated pollution," continues Eric Servat. And yet, 70% of the freshwater available on our planet today is dedicated to agriculture. "In a modified and degraded context in terms of water resources, these demographic evolutions oblige us to imagine an adapted agriculture for the future ".

Growing inequalities

As the oceans continue to rise, the risk of marine flooding is increasing on French coasts - where the sea will rise by 26 to 55 cm by 2100 - threatening populations and infrastructures. We can therefore expect climate refugees in our latitudes. But this risk mainly concerns the southern shores. Unequal development, unequal vulnerability: not all human societies are equally threatened.

In the North, structures and resources should enable us to adapt. Vineyards in difficulty, chestnut groves on the verge of extinction? Scientists believe this is to be expected. But " climate change is also a source of new opportunities," points out Patrice Garin, researcher at the " Gestion de l'eau, acteurs et usages " laboratory: this will be the case in our mid-latitudes, with the possibility of orange and lemon trees blossoming ". In the South, on the other hand, where severe droughts are already raging, some populations will have to leave lands that will no longer feed them.

Promoting agrodiversity

And when agricultural production is threatened in the Mediterranean, " it's the cradle of agriculture that is affected," says Yildiz Aumeeruddy-Thomas, a researcher at the Centre d'Ecologie Fonctionnelle et Evolutive. The wild relatives of the cereals and legumes that feed humanity today are here," she explains. This agrodiversity is a major pillar of global food security. " Plantations today are often monoclonal: a single individual, replicated thousands of times ". Highly specialized varieties, created in laboratories for their productive capacities. But they are also " environmental aberrations ", according to the ethnobiologist...

" By planting monoclonal varieties, we not only lose genetic resources, but also valuable know-how. On the contrary, we should be promoting older, hardier varieties that are better adapted to their environment. And promote the biodiversity associated with agroecosystems, to increase their adaptability. Aiming for food security rather than overproduction for export: this is also the guarantee of food quality that pays off. " Conventional agriculture requires the massive use of chemical products, which have an enormous cost in terms of public health, which must be taken into account in the future when considering new agricultural models ".

Cost of inaction

While disruption is inevitable, its scale will depend on the ability of public policies to manage the crisis. For Patrice Garin, " we need to think about other ways of sharing out the territory, of exploiting and occupying space, of developing urbanization ". He advocates a model of society that is " more frugal and more respectful of the environment ". It also calls for the participation of civil society, and in particular scientists, to support decision-makers in their exploration of the field of possibilities.

Whatever strategies are followed, they will have a cost. But " doing nothing costs even more," points out Sophie Thoyer, professor of agricultural and environmental economics, and researcher at the Lameta laboratory, now the CEEM. " According to certain studies, it is estimated that the cost of inaction increases by 40% every 10 years. Not to mention the irreversible, indecipherable effects: the disappearance of the ice cap, for example.

An observation made against a backdrop of lacklustre political will. Is Europe aware of the urgency of the situation? " The Common Agricultural Policy recently green-lighted its action. But the measures taken are very timid in relation to the issues at stake, and will have very little impact on the environment". And what about the non-binding agreement signed at the recent COP21? For Sophie Thoyer, " it has an incremental value. Its success lies in the fact that the 195 countries reached a consensus and the momentum has been re-launched, with the aim of achieving ever-greater commitments ". A gentle method that could bear fruit. But how long will it take?

Key words : Climate change, Climate, LUM#2, LUM Magazine