Global light pollution rises but falls sharply in France, study finds

Findings highlight the impact of French street lighting policies on biodiversity, sleep and energy use

In Corrèze, the Millevaches Plateau, which is free from light pollution, has been designated a ‘Dark Sky Reserve’
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Good news for nocturnal wildlife, poor sleepers, and night sky watchers: light pollution levels in France are bucking the worldwide trend and have decreased by 33%.

A study published in the British journal Nature revealed findings by American and German researchers, based on 1.16 million images taken around the world by NASA satellites. It was able, reported France Inter, to create a precise map of the evolution of global light pollution between 2014 and 2022.

While light pollution worldwide increased by 16% – with Africa and Asia showing the biggest increases of 21% and 38% respectively – in Europe, it fell by 4%.

In France, it decreased by 33% thanks to policies to reduce public lighting, with the aim of protecting nocturnal biodiversity (insects, migratory birds and marine species) and reducing electricity bills.

In humans, prolonged exposure to light at night disrupts the production of melatonin, the hormone responsible for regulating sleep. Medical studies link sleep disruption to a greater risk of cardiovascular disease, metabolic disorders, and some cancers.

A note of caution was urged, however, because the satellites capture images in the middle of the night, when streetlights are often turned off, and do not accurately measure certain wavelengths, particularly those emitted by LEDs. This apparent decline therefore does not always reflect the reality on the ground, said 20minutes.

In 2024, more than a third of municipalities in mainland France turned off streetlights at night, when advertisements and illuminated signs must be turned off from 1am–6am.

France sued over seabird extinction

Three organisations are suing French authorities for a failure to act on the risk of seabird extinction due to a lack of monitoring of fishing activities.

According to ClientEarth, Sea Shepherd France, and Défense des Milieux Aquatiques (Defense of Aquatic Environments), France has some of the highest rates of seabird ‘bycatch’ – the accidental catching of birds by fishing nets – in Europe. Some species are now considered critically endangered, they said.

“Tens of thousands of seabirds are killed each year off the French coast due to fishing gear, caught in fisheries targeting hake, sea bass, and tuna, among others. 

“France has some of the highest seabird bycatch rates in Europe, affecting species such as the Balearic Shearwater (Puffinus mauretanicus), the Northern Gannet (Morus bassanus), and the Common Murre (Uria aalge), species which are now classified as critically endangered, near threatened, and endangered, respectively, according to the Red List of the International Union for Conservation of Nature,” they added.

The Balearic Shearwater (Puffinus mauretanicus) has been affected by seabird ‘bycatch’

The three NGOs argue that “France has failed to fulfil its data collection obligations or implement measures to reduce bycatch, in violation of the Birds and Habitats Directives, the regulation on technical measures, and other European data collection requirements.”

Cruise ships on-grid in Marseille

In Marseille, up to three cruise ships can now shut down their engines while docked and run on electricity, thanks to massive electrification upgrades at the Bouches-du-Rhône port.

The ships are connected via thick cables to mains electricity at a terminal on the pier so that the port can supply each ship with a maximum of 16 megawatts of power – equivalent to the consumption of a town of 13,000 residents – at the shipping company’s expense.

The electricity supply will cover the ships’ energy needs, such as for restaurants, air conditioning and lighting during the port call.

Marseille has invested €200 million in the electrification of the quays in order to banish black smoke and polluting emissions generated by the ships. “We are going to reduce fine particle emissions by 75%,” said a port spokesman.