More than 70% of harmful emissions that affect the climate and human health come from cities”, the WWF says, indirectly confirming that the problem is not “intensive livestock farming”.

“Over 70% of the harmful emissions that affect the climate and human health come from cities,” the WWF says in promoting its “Urban Nature” initiative. The celebration of nature in cities returns for its eighth edition with hundreds of events across Italy, culminating in the grand finale in Rome on Saturday, 28 and Sunday, 29 September, 2024. The event aimed to raise awareness of the importance of urban green spaces and their role in combating the negative effects of climate change and urban pollution. This indirectly confirms what we have long emphasised: the main culprits of climate and atmospheric health problems are not the so-called “intensive livestock farms”.

According to WWF, cities’ lack of green spaces contributes significantly to rising temperatures, air pollution and an increased risk of extreme climate events. The lack of green spaces in cities is one of the main factors behind the creation of heat islands, caused by the disproportionate use of building materials such as asphalt, cement and metal compared to the presence of green spaces. The WWF reminds us that over 4% of summer mortality in European cities is due to urban heat islands. In 2023 alone, heat caused 47,690 deaths in Europe, with Italy being one of the countries most affected by heat-related daily mortality.

This data further exonerates livestock farming as the main source of emissions. The annual ISPRA report, produced by the Italian Institute for Environmental Protection and Research, which collaborates with the WWF initiative, had already pointed out that agriculture in Italy was responsible for around 7% of fine particulate emissions and 2.5% of PM2.5 emissions, the most harmful particles. Meanwhile, transport, heating and industrial activities are responsible for the remaining 93%.

Enhancing urban green spaces

The WWF emphasises the enhancement of urban green spaces as an effective solution to mitigate environmental damage, as planting trees and plants in cities can significantly reduce temperatures, prevent flood damage, mitigate sudden storms and improve air quality. In fact, urban forests can remove up to 20% of the particulate matter emitted by traffic, construction and industry. One hectare of urban forest can remove significant amounts of PM10 and tropospheric ozone, improving public health. In Medellín, Colombia, for example, “green corridors” created by increasing the number of trees and plants have reduced the average local temperature by about 2°C, helping to improve air quality and demonstrating that increasing urban greenery is an effective and essential tool for mitigating the effects of climate change.

“In terms of pollution, just one hectare of urban forest can remove an average of 17 kg/year of PM10 and 36 kg/year of tropospheric ozone present in the layers of the atmosphere where we live,” Eva Alessi says, Sustainability Manager at WWF Italy. “With Urban Nature, our celebration of nature in cities, we want to spread the value and care of nature in urban environments for the well-being of people, renewing the way we think about and plan spaces and promoting virtuous actions by administrators, communities, citizens, businesses, universities and schools to protect and enhance biodiversity in urban systems“.

Urban green spaces are beneficial, but be mindful of fires

However, it should be added that “urban greenery is a great thing, but the increase in biomass in populated areas makes it more difficult to contain interface fires, especially if this increase is uncontrolled. Look at the case of Rome this year,” Giuseppe Pulina comments, professor of ethics and sustainability of animal husbandry at the University of Sassari. “The fact is that we rarely consider that fire is a living entity, in the sense that it wouldn’t exist without life (biomass to burn) and oxygen (produced by plants and algae). So yes to public green spaces, but no to urban forests that could become more of a risk than a benefit“.

“If we want cities to function like the countryside,” the expert adds, “we need to disarticulate the urban system with urbanised islands in a vast territorial matrix with large mosaics of ecosystem services. It’s a bit like the Italian model, which, instead of sending everyone to large urban areas, has preferred territorial dispersion with the ‘province’ model. As long as this model preserves rural corridors for agriculture and doesn’t fill them with concrete from industrial and commercial zones, which would nullify their positive impact on climate and water management. We already have the countryside in the cities: we just need to think about it, plan it and preserve it”.