According to UN Habitat, although cities amount only for less than 2 per cent of the world surface, they consume 78% of global energy and generate more than 60% of total greenhouse gas emissions. The use of polluting fuels to respond to the high demand of energy in urban areas not only increases dramatically the levels of air pollution, but it also worsens and accelerates the effects of climate change. The World Health Organizationestimates that nine out of ten people now breathe polluted air, increasing the occurrence of diseases such as lung cancer and heart stroke; as a matter of fact, health problems related to air pollution cost around 4% of the national GDP of the most polluting countries.
The link between air pollution and climate change creates a vicious circle that will keep existing unless policy-makers implement measures to adopt the use of new, sustainable sources of energy. Cities concentrate large amounts of traffic and industry, both of which emit the highest levels of greenhouse gases into the atmosphere, which in turn are the main cause of global warming and climate change. At the same time, climate change has led to the warming of the world, thus decreasing rainfall while increasing temperatures: this, added to high air pressure and high cloudiness, leads to a higher level of pollution.
Many large urban areas, especially in Europe, have started implementing measures to tackle the problem of air pollution as a response to the growing environmental awareness among the civil society. In Paris, which is one of the European cities with the worst air quality, the municipal government decided to ban the access of cars made before 1997 into the city center on weekdays as well as to declare the first Sunday of every month car-free. In London, most automobiles entering the Congestion Charging Zone in the center during daytime must pay a daily “congestion fee” which has already shown great results: since it was introduced in 2003, the number of vehicles in central London has declined by 30%. German cities such as Munich, Frankfurt and Berlin have also decided to ban old diesel cars in some specific areas after separate rulings of Administrative and Federal Courts. During pollution peaks mostly characterized by the absence of rain, cities like Paris and Madrid have introduced a system based on registration plates: even-numbered plates would be allowed one day, while odd-numbered ones would be allowed the next.
In Madrid, the previous leftist government established a zone covering 472 hectares which only allowed the access of cars belonging to residents and public transport, thus imposing a fine on any vehicle without an “eco label” (e.g. hybrid) that would enter this downtown area called Madrid Central. Aiming at reducing pollution by 40% in the affected area in accordance with the Commission’s Air Quality Directive, the initiative achieved great results despite its short life: only during the first three months of its existence, sales of hybrid vehicles equaled those of 2016, the use of public transport saw a great increase (which led to a higher regularity and frequency of buses and trains), and air pollution levels decreased to historical values month after month. However, the unexpected rise and victory of the (extreme) right-wing coalition in the Spanish capital poses an enormous threat to all these achievements: soon after they took office, the three-party coalition decided to establish a moratorium on the fining system for any vehicles entering Madrid Central. In practical terms, this moratorium means the end of an ambitious project aligned with European standards. If Madrid thus goes back to exceeding the targets on greenhouse gas emissions set by the Commission, it may face a fine of around €500 million. In fact, an Administrative Court has already noted this, forcing the municipal government to suspend the moratorium in an effort to keep the Madrid Central project alive.
Apart from setting restrictions on traffic, cities around the world are also implementing a series of novelty measures to provide incentives to decrease the use of private means of transport and increase that of public transport. In Milan, for instance, besides electric bicycles and a comprehensive bus and underground network, the municipality has now decided to introduce a new transport system lowering and standardizing train fares to other nearby municipalities, which will thus hopefully persuade daily commuters to leave their vehicles safely parked at home.
The case of Madrid is a clear example of the politization of the environment and of how some politicians would rather reverse a beneficial initiative instead of admitting that the opposition might have been right. However, the administrations of most big cities are becoming more and more conscious about the detrimental effects of pollution, and their decisions are increasingly backed both by the population and the judiciary. Hopefully, this will only be the beginning towards a fully sustainable urban atmosphere.
