COUNTRIES ACROSS THE world have already been observing Earth Hour today, with Hong Kong’s skyline dimmed and the sails on Sydney’s Opera House going dark today.

Millions of people are expected to take part in the annual event organised by conservation group WWF, with hundreds of well-known sights including the Eiffel Tower in Paris and the Seattle Space Needle set to plunge into darkness.

Earth hour takes place from 8.30pm local time and encourages citizens, communities, businesses and organisations to switch the lights off for an hour to highlight the plight of the planet.

The restaurant at the Four Seasons Hotel in Dublin observed Earth Hour back in 2008. Maxwells / PA Maxwells / PA / PA

This year it comes ahead of a crucial UN meeting in Paris in December which is bringing together the global community in an effort to limit global warming.

The initiative began in Sydney in 2007 but quickly went global.

“Over 170 countries and territories have already confirmed their participation; more than 1,200 landmarks and close to 40 UNESCO world heritage sites,” Earth Hour head Sudhanshu Sarronwala told AFP ahead of the event.

Earth Hour’s goal is not to achieve measurable electricity savings, but to raise awareness of the need for sustainable energy use, and this year also to demand action to halt planet-harming climate change.

“We hope that with each light switch that goes off, the light cast on people calling for action becomes clearer and paves the way ahead for climate action,” said Sarronwala.

• Will you be switching out the lights for Earth Hour?

- With reporting from AFP. 

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