The Provence-Alpes-Côte d' Azur region covers the 6 departments of Alpes de Haute-Provence (04), Alpes Maritimes (06), Bouches-du-Rhône (13), Hautes-Alpes (05), Vaucluse (84) and Var (83), representing 963 municipalities over 31 400 km2.
From west to east, there are nearly 900 km of coastline bordering the Mediterranean. The coastal regions are followed by the low shores (the Camargue and Crau) and the high cliffs of the Calanques. In the north and east, mountainous regions prevail. The glacier valleys of the Hautes-Alpes peak at 4,102 metres. Between these two large complexes lies the inner Provence, formed by hills and hillsides. This exceptional territory is the subject of numerous protections and labelling with 8 regional nature parks, 4 national parks, 12 national nature reserves, 5 regional nature reserves and 3 biosphere reserves.
The Provence-Alpes-Côte d' Azur region has 4.9 million inhabitants, 90% of them residing in the 3 major metropolises of Marseille, Nice and Toulon, or in medium-sized towns with more than 20,000 inhabitants.
The Aix-Marseille-Provence metropolis comprises 92 municipalities, covering an area of 3,148 km2, i. e. 10% of the regional surface area. It is thus the largest metropolis in France: four times Greater Paris and six times Greater Lyon.
The metropolitan area has an exceptional and diversified geographical and landscape setting. In contrast to the numerous hilly massifs and their valleys to the east, the water bodies of the lagoon of Berre and the lagoon of Bolmon to the west stand out. The coastline, 255 kilometres long, alternates between industrial and port spaces (Fos-sur-Mer area, Grand Port maritime, port of La Ciotat) and picturesque natural spaces, including the famous calanques between Marseille and Cassis. The terrestrial territory is marked both by numerous natural areas, some of which are remarkable for their protection, and by strong, multipolar urbanisation.
With 1,850,000 inhabitants, Aix-Marseille-Provence is also the most populated of the regional metropolises. The two major urban centres, Marseille (858,000 inhabitants) and Aix-en-Provence (142,000 inhabitants) have a combined population of one million, or 54% of the city's population. However, the population growth of the metropolis, like that of the PROVENCE-ALPES-CÔTE D' AZUR region, has been declining for the last ten years with an annual growth rate of only +0.4%.
A land of contrasts, rich in its natural heritage as well as in the plurality of human activities that develop there, the metropolis of Aix-Marseille-Provence is both a source of opportunities and a source of real stakes in terms of land use and development.
The challenges of the territory
" Preserving and enhancing our resources - For an attractive, sustainable and united metropolis at the heart of societal aspirations and the best way to live together "- AgAM - November 2017.
" Aix-Marseille-Provence, comprendre l' espace métropolitain ", Atlas cartographique - AgAM - June 2016.
Regards de l' AgAM n°39 - " Improving air quality A metropolitan scale challenge " - AgAM - October 2016.
The natural spaces of the metropolis are remarkable but under pressure from urbanisation, pollution, local and tourist traffic. On average, nearly 200 ha/year of agricultural and natural land was affected by urbanisation between 2006 and 2014. Moreover, they are fragmented by motorways, expressways, TGV lines, canals...
The high density of the population and its attachment to its territory translates into a very high use of natural spaces which become spaces for relaxation and leisure on land and water. There are many signs of deterioration: areas regularly burned down, uncontrolled landfills, water pollution, conflicts of uses... In order to preserve biodiversity and landscapes, many more or less restrictive regulatory protections on natural areas have been put in place: the Calanques National Park, the National and Regional Nature Reserves, prefectoral biotope protection orders, classified and inscribed sites correspond to strong site protection.
However, several sectors are still orphaned, especially in the north of the metropolis, such as the Trevaresse chain and the Rognes and Montaiguet massifs. Other areas are protected, but only partially: the Estaque chain, the Arbois plateau, the banks of the Berre pond and associated wetlands...
The challenge is to fill gaps in terms of protection and management of areas, in order to preserve the major balances in the structuring of the territory. The challenge is also to preserve and even restore the connections between these reservoirs of biodiversity, in the perspective of a green and blue grid of metropolitan scale. This issue takes on a particular dimension with climate change: some species will have to be able to migrate in order to adapt.
Moreover, on a territory heavily impacted by outdoor air pollution, classified as carcinogenic by the World Health Organization in 2013, the first challenge is health. Sustainable reduction of the population's exposure is essential to guarantee a quality living environment. This is particularly the case in urban centres, which are expected to be increasingly dense and which accumulate other nuisances such as noise and the phenomenon of heat islands. It is also about reducing environmental and spatial inequalities and improving the attractiveness of the territory. On the other hand, striving to comply with the air quality thresholds set by the European Union will avoid disputes with the European Court of Justice in France, as is currently the case with particulate matter. One of the answers is to conduct an integrated emissions reduction policy at a relevant territorial scale. Future reflections on housing, mobility and development policies in the development of the Metropolitan SCoT should contribute to providing more qualitative and respectful responses to environmental and quality of life issues. The challenge is also to integrate climate and energy policies in a double logic: reducing greenhouse gas emissions, adapting to current developments.
Finally, the metropolis is confronted with the more global challenge of adaptation and resilience to the impacts of climate change. Regional forecasts of increases in temperature, the frequency and intensity of heat waves or water stress will have an even greater impact on the urban population, due to their amplification in urban areas. The study and implementation of biases in climate change mitigation and resilience to their impacts is therefore a major challenge for the territory in the years to come.
To go further
Headquartered in the metropolis of Aix Marseille Provence, Marseille is the second largest city in France with 861,635 inhabitants and the third largest city with 1,578,584 inhabitants. Extending over 240 km2, Marseille is a city of contrasts, diversified, sheltering both a dense and very urban city centre and remarkable natural spaces including the famous massif of the Calanques. The port city, located between the waters of the Mediterranean Sea on one side and the hills of Estaque, Etoile, Garlaban and Saint Cyr on the other, has been growing for 2600 years and is nowadays becoming a major economic hub of the regional territory and an increasingly popular tourist destination.
More specifically, the city of Marseille is facing multiple climatic challenges due to its characteristics, for example:
- A impoverished population in the urban centre and a high demographics
- A strong urbanization
- Important tourism activities
- Natural spaces between the sea and fragile land
- A climate already conducive to fire and topography/hydrography conducive to flooding
- A geographical area suitable for the development of certain disease vectors (chikungunya)
To limit climate change, reducing greenhouse gas (GHG) emissions at source must remain a priority in transport, housing, agriculture, waste treatment, energy production, etc.... But the climate machine is difficult to slow down: the lifespan of GHGs being several tens or hundreds of years, even if we succeed in drastically reducing our emissions, a warming of our planet is inevitable and the impacts will be felt for several hundred years.
The Toulon Provence Méditerranée metropolis includes 12 communes on a territory of 36,654 hectares. The metropolis has 437,460 inhabitants (source: INSEE, legal population in force as of January 1,2018), representing more than 40% of the population of the Var department.
Between sea and land, the territory classified as the most touristic in France has more than 200 kilometres of coastline and mountainous massifs offering hiking trails with an exceptional panorama.
The challenges of the territory
With a view to the future impacts of climate change, certain territorial issues are emerging as a priority for the metropolis. This includes issues such as air quality and health, water availability and quality, the safety of infrastructures and habitats, and the protection of natural and agricultural heritage.
In fact, the increase in average annual temperatures will be accompanied by a consequent decrease in the quantity of water available on the surface and underground. The water problem will also be qualitative, with a deterioration in the physico-chemical quality of the water, which could lead to a disruption of the drinking water supply, conflicts of uses, but also a significant disruption of aquatic ecosystems due to an increase in water temperature and a decrease in flows.
This average temperature increase will be associated with an increase in the frequency and duration of heat waves and heat waves. However, these phenomena have an impact on air quality and hence on the health of populations. Air quality degradation, particularly by ozone and fine particulate matter, could pose a threat to the health of fragile populations such as the elderly and young children.
Beyond the development of resilience to these phenomena, the challenge is also to adapt the lifestyles and human activities that contribute to them: reducing greenhouse gas emissions and pollutants in the territory, reducing energy consumption, increasing the production of renewable energies.
In addition to water and air issues, these increases in temperature and decreases in annual precipitation lead to new challenges for agriculture, viticulture and the preservation of natural areas and biodiversity. These climatic changes could lead to yield losses (mainly in horticulture), quality and typicity of agricultural production. The loss of quality and typicity of the grapes represents a strong risk for viticulture as it could lead to the loss of AOC designations. They would also lead to a change in the ecological balance of natural environments and biodiversity (terrestrial and aquatic), as well as the possibility of introducing and/or developing invasive species.
Climatic hazards will also increase the risk of marine submersion and flooding. It is therefore necessary to anticipate and apprehend the issues of public safety and security and the protection of facilities, infrastructures and habitats. The adaptation of human activities, whether agricultural, viticultural, tertiary, industrial or tourist, to these risks of flooding and submersion is also an important territorial challenge.
To go further
The Nice Côte d' Azur metropolis covers 46 municipalities over 1,400 km2, or one third of the surface area of the Alpes-Maritimes department. It has 550,000 inhabitants, the majority of whom live in urban areas (79%), between Nice, Cagnes-sur-Mer and Saint-Laurent-du-Var.
The metropolis offers a mosaic of landscapes witnessing the geographical diversity of the territory, from the Mediterranean Sea to the summits of Mercantour. Beyond the variety of landscapes and places of life, three distinct spaces are defined by their geographical characteristics, the forms of land use and the economic activities that develop there:
The coastal frontage marked by a strong tourist and economic attractiveness, a place of concentration of the urban character and economic activities of the metropolitan territory.
The Middle Country, formerly agricultural, which is today a highly strategic area of urban expansion and economic development with the Operation of National Interest (OIN) Plain of the Var.
The Haut Pays Montagnard, characterized by natural areas and biodiversity of great richness, a specific object of protection with the Mercantour National Park in particular, and where the economy is largely based on agricultural, forestry and pastoral activities.
The challenges of the territory
Excerpts from PCET NCA (2012/2017) - Volume 3 - Diagnosis of Territory Vulnerabilities to Climate Change.
The strategic challenge posed by climate risk is considerable at the territorial level: environmental, economic and social impacts directly influence the quality of the inhabitants' living environment and the preservation of local resources. It is therefore necessary to anticipate and adapt to the potential impacts of climate change on the territory.
Climate change will have multiple impacts on water resources, both on supply (quantity and quality) and on demand (increasing water needs). Despite the good availability of water resources on the territory in the short term, the prospects for territorial development (urbanisation, population growth, hosting of new activities, pressures on watercourses) suggest that in the long term, pressure on the use of water resources will increase and potential conflicts to be anticipated (drinking water, water consuming activities, agricultural uses, energy uses, etc.). Nevertheless, today, the real short-term problem is the preservation of water quality in the territory.
Climate change is likely to increase the frequency and intensity of extreme events (IPCC, 2012). As a result, several issues will become increasingly restrictive for the territory:
- Flood risks: problems of urban runoff to be integrated;
- Risks Withdrawal Clay Swelling: little considered to date;
- Forest fire risks: numerous warning systems to reinforce and anticipate the risks of fires in peri-urban areas;
- Littoral risks: although coastal erosion is currently underway, the phenomena of temporary flooding must be anticipated in view of the high sensitivity of the coast to its activities.
It is therefore necessary to integrate a prospective dimension into the tools for the prevention and protection of natural hazards.
The metropolis has five times more natural spaces than the old urban community. By comparing the knowledge and expertise of the Mercantour National Park, the Parc Naturel Régional des Préalpes d' Azur and its services, the Metropolis provides the scale and means to fully understand its green and blue grid despite the strong distinctions between the issues linked to the coastline and those of the Upper Country. The first challenge of the Metropolis lies in its capacity to protect, manage and enhance the richness and diversity of this natural and urban landscape heritage. Various tools are currently being put in place, such as the Mercantour National Park, the OIN Plaine du Var, the bay contract and river contracts. The complexity of the interactions between biodiversity and climate make it difficult to identify the most fragile areas on a regional scale. It is therefore necessary to improve the knowledge of species and species that may be affected by the effects of climate change.
With its structuring skills in planning and development, the Metropolis must now integrate or implement a climate component in the forward thinking initiated at the regional level (SCOT, PLU, etc.). Thermal discomfort situations may have a greater and more regular impact on the quality of the inhabitants' living environment (urban heat islands). Thus, as of today, the priority is to anticipate the construction methods and the development of neighbourhoods so that the quality of life is the same in a few years.
The energy sector is directly linked to the climate. The production capacity required to meet energy requirements (heating, cooling) depends on climatic conditions. Observed and expected climate changes could therefore have potentially significant impacts on the energy system at several levels:
a change in energy demand: likely increase in energy needs for cooling in summer due to high temperatures;
production difficulties in summer due to lower river flows (hydroelectricity) and higher temperatures of water used as a cold source for conventional nuclear and thermal power plants;
Difficulties in the distribution of energy with the possible degradation or even destruction of service infrastructure;
increasing the vulnerability of power generation infrastructure to extreme events.
Due to its dependent energy situation, the territory has initiated for several years a contract of energy security in the East PROVENCE-ALPES-CÔTE D' AZUR. In continuity of these works, the territory will have to face potential impacts of climate change on energy consumption and production on a territorial scale.
In parallel with the reduction of agricultural activities on the territory, there is an increase in the area of forested areas. Despite this correlated dynamic, these two sectors are largely dependent on climatic conditions. Climate change can be a positive factor, and climate change offers new conditions for productivity in the region. However, negative effects such as productivity, geographical distribution, etc. have an impact. Forest management and land-use planning must now take these trends into account in order to adapt practices and reduce the vulnerability of forest stands to dieback, fire risk, etc. Thus, climate change exacerbates a dynamic of pressures already under way on agricultural activities. To date, few analyses have been initiated on the impact of climate change on agricultural productivity in the territory.
Tourism is largely linked to local climatic conditions, which constitute an essential criterion for the choice of tourist destinations. A change in climatic parameters could lead to significant changes both in the tourist attendance schedule (extending the summer season, increasing "off-season" attendance) and in the distribution of flows within the territory (e. g. seeking freshness in summer in the mountains, or ascending to higher altitudes for winter tourist activities) and possibly in the nature of tourist activities (new practices, abandonment of some...). Impacts would be foreseeable on the territory, particularly for the activity of mountain resorts, largely dependent on climatic conditions.
Climate change, through extreme events and predicted warming, will undoubtedly affect human health. The health risks linked to these changes will be accentuated and new health phenomena, which are currently not easily understood, could even appear. The PROVENCE-ALPES-CÔTE D' AZUR region, and more specifically the territory of the Metropolis, is particularly concerned by the risk of the emergence or extension of certain infectious diseases whose vectors are already present around the Mediterranean. Furthermore, an increase in the number of people vulnerable to heat is expected as a result of rising temperatures, coupled with an aging population and the concentration of populations in urban areas (InVS, 2010). Coupled with a vulnerable (elderly) population, these foreseeable effects of climate change on populations require the mobilization of health sectors to deal with this problem on the scale of the Nice Côte d' Azur metropolis.