Paris’ coolest secret: Keeping Mona Lisa smiling

In a bid to combat the effects of global warming, adaptive measures are in place to keep Paris cool.

A network of ice-cold pipes lay 30m beneath the ground, covering a distance of nearly 90km and cooling the air at more than 700 locations across the city of Paris.

This includes the Louvre, where Mona Lisa, among 550,000 other artworks reside, where there is no air conditioning.

The cold water provided by the pipes is essential in preserving the artwork, allowing museums and galleries across the city to be able to control their temperature and humidity.

The system works by taking cold water from the River Seine and circulating it through a network of underground pipes, which is then injected into the air to reduce temperatures.

It is generated purely on renewable resources, and the heat that is created as a by-product, is then sent back into the Seine.

Whilst it is already the largest in Europe, there are plans to triple the network by 2042 to make it the largest urban cooling system in the world. The pipe network aims to reduce the temperature of the city centre by 1C.

Other adaptive measures, such as air conditioning, could in fact have a negative impact in the long-run.

This is because it releases excess waste heat into the environment, exacerbating the urban heat island effect and further increasing cooling demands.