A man whose bicycle is equipped with LED lights riding near Merlion Park after lights in the Central Business District were switched off or dimmed at 8.30pm yesterday for an hour to herald Earth Hour, a worldwide movement to raise awareness of climate change.

The initiative by the World Wildlife Fund, which Singapore first observed in 2009, was marked across the island.

Malls such as those run by Capitaland, hotels like Pan Pacific Singapore and FairPrice supermarkets switched off non-essential lights, while grassroots organisations, including those in West Coast, Hong Kah North and Jurong Spring, held eco-friendly carnivals.

The main event was the free Earth Hour Concert on the Float@Marina Bay.

Elsewhere, cities on Australia's east coast were among the first in the world to go dark. The Sydney Opera House, normally brightly lit, switched off its lights, along with the Sydney Harbour Bridge. Other global icons such as the Eiffel Tower in Paris, the Empire State Building in New York City, and Taipei 101 also turned off their lights.

This year's theme is a celebration of "Places We Love", such as beaches, forests, reefs, snow-capped mountains and rivers, which could be at risk from climate change. In Singapore, Malaysia and Indonesia, the focus was on united action to protect forests and stop haze pollution.