Climate change: Cities can be subjected to twice as much temperature increase so what can be done?
As the climate crisis is causing significant temperature changes around the world, big cities have become massive hot boxes. The accumulation of multiple factors such as air conditioning use, the number of cars releasing Co2, and a lack of fountains and green corridors means that cities can be, especially in summer, a trap for the elderly, children and the most vulnerable.
According to the United Nations, more than half of the world's population lives in cities and this figure is likely to rise to more than two-thirds by 2030. Cities consume a large share of the world's energy supply and are responsible for about 70 per cent of the world's energy-related greenhouse gas emissions, which absorb heat and cause global warming.
The primary victims of the increased heat in cities will be the elderly, children and people living in poverty.
Urban warming expert Harriet Bulkeley, professor at Durhan University and the Copernicus Institute at Utrecht University says:
"Access to nature in cities is very diverse and it's the poorest areas that have the least access. That means that some of the people most vulnerable to the effects of heat do not have access to the solutions that can help them. So as we go forward and think about presenting nature in terms of green spaces or open spaces to support communities responding to heat, we need to think about how we're going to put the most vulnerable first."
She suggests working with schools and various communities in order to understand how they have access to nature could help develop solutions. She highlights that in many cases, the poorest city communities are often the ones with the least access to nature and the least resources. However, they could make all the difference in the fight against global warming.
She adds that a sustainable and just society would help those most vulnerable to the effects of global warming access the help they really need.
" That will be key in the future because otherwise, we won't reduce the impact that heat will have on cities in terms of the challenges it will have for people's health or for their well-being or our economy unless we make sure we bring the most vulnerable with us as well."
Cities such as Malmo in Sweden, Paris, Milan, Barcelona and Lisbon have successfully implemented public policies to limit the impact of climate change. There is enough accumulated experience to identify the main hazards that contribute to global warming in the city.
For Athens Sustainability Advisor Eleni Myrivilli, an expert on urban warming, "The first - of the hazards - is cars. They are a big problem and really inconsiderate. Moreover spending on air conditioning is really bad and stupid. The use of air conditioning is also a very big problem (...) We have to learn how to do green and blue infrastructure in cities or mixed infrastructure, grey and green together. And that is going to take time. We have to change the way we shop. (...) another enemy is that our politicians often still don't make climate change a priority, which also has to do with our own communities.
In the current situation, response measures would not be delayed at the risk of aggravating the situation.
For Bulkeley, "The first thing would be to maintain what we have. And the second would be to try to introduce more nature and blue areas in cities, which could be in the form of green walls, green roofs, small parks in the streets, and shady trees. (... .) We could start by simply painting roofs white. Much of our asphalt in cities is also very dark. And the more dark surfaces we have in cities, the more heat they absorb. (... .) Introducing blue areas in cities may be a bit quicker than growing the nature we need in cities to sustain us (...) We can think about the pavement. So, removing some of the pavement we have in our cities."
Ingenuity is urgently needed to get the ball rolling. The World Economic Forum in Davos pointed to a number of possible solutions to help keep cities cool. Examples range from improving sanitation by recycling waste to the impact of planting small urban forests.
If scientists claim that a single tree can capture up to 22kg of CO2 in a single year, there are forestry intervention companies that claim that when several species are grown together, the trees grow faster and capture up to six per cent more CO2.