What is Earth Hour?

Earth Hour is an annual global campaign that encourages people and businesses around the world to switch off electricity at the same time for one hour. Earth Hour started in Australia in2007 when 2.2 million people in Sydney turned off all non-essential lights for an hour. Since then it has grow in to a massive global event. In 2013, millions of people in 7,000 cities and towns around the world switched off their lights for 60 minutes at the end of March. Every year landmarks and well-known buildings around the world take part and go dark for Earth Hour. The campaign even went into space when astronauts reduced power on the International Space Station in 2011.

Earth Hour is organized by the World Wide Fund for Nature (WWF). It was started by Andy Ridley who is executive director of Earth Hour Global, WWF. He came up with the idea because he wanted to raise awareness of environmental issues by asking people to do something positive to help the planet. Switching off the lights for an hour can make a small difference to the amount of energy we use but Earth Hour is also a symbolic event to make people think about the problems of climate change.

The end of March is around the time of the spring and autumn equinoxes(昼夜平分时) in both hemispheres (半球) respectively, when sunset times are at similar times. This means that a global “lights out” event has most visual effect at this time of year.

As well as famous London landmarks such as Big Ben, London Eye and Buckingham Palace switching off their lights, there are many other events around Britain. On the WWFs interactive map you can see which people, businesses, schools, organizations and landmarks are taking part each year and what they are doing.

We’re all familiar with the idea of climate change and how our planet is warming. Extremes in temperature have become more commonplace, making parts of the world difficult to live in. But one place where excessive heat is making life very uncomfortable is our cities. Luckily, innovation might be keeping a lid on it.

As thermometers record temperatures, sometimes above 50 degrees Celsius, solutions are being sought to cool the air in our cities. In India, for example, heatwaves and rapid urbanisation have led to a big rise in the use of air-conditioning units, adding to CO₂ emissions. So, architects, looking for a sustainable cooling solution, are reviving an ancient “lattice” design, used in old buildings like the Taj Mahal, to construct comfortable, low-car-bon buildings. Yatin Pandya said: “Traditional architectural forms have proven their performance in combatting environmental conditions.”

In America, about 80% of the population lives in cities, and it’s these cities that suffer from an urban heat island effect, caused by factors such as trapped waste heat, concrete structures and pavements absorbing the sun and tall buildings blocking the wind. Residents and developers have tried to heatproof these places by planting large trees that offer shade and putting plants and gardens on top of roofs that use vegetation to help trap heat. And in Los Angeles, there’s an experiment to cover streets with light-coloured material that reflects rather than absorbs the sun and so they remain cooler than typical black roads.

But it’s satellites in space that are really giving us the best picture of our over-heated cities. Glynn Hulley, who is leading an image-capturing project, called the Land Surface Temperature Monitoring mission, said: “The data can be used to identify hotspots, vulnerable regions, and assess the cooling impacts of heat mitigation approaches.” It’s already found how green spaces, white roads and water features, have helped prevent our cities from boiling over. But with excessive heat still posing a threat to our lives, more solutions are still needed.

Located at a depth of 20 feet below the surface, the sand of the ocean floor off the coast of the Florida Keys might be an unlikely spot to host a music festival, but that hasn’t stopped music enthusiasts from diving underwater to rock out.

For the past 35 years, the Underwater Music Festival, an event that pairs music with conservation, has been hosted. Equipped with guitars, drums and other musical instruments, divers go down to the depths and play along to a playlist of water-inspired songs that are piped underwater via speakers. Over the years the event has gone from being a small grassroots effort put together by few locals, with the idea that once people see what’s going on beneath the surface, the more likely they would be to protect it, to a two-day festival that draws dozens of divers, boaters, and musicians to the Keys from around the world.

“Thirty-five years ago a few Keys locals sat down and wanted to figure out a way to bring awareness to our coral reefs （珊瑚礁）that would preserve, rebuild and restore them in any way,” says Dave Turner, executive director of the Lower Keys Chamber of Commerce. “They came up with this idea of playing music underwater and invited people to listen while also enjoying the local sea life.”

“The preservation of the reef is our main purpose,” Turner says. “To avoid any further damage, the festival takes place in a nearby sandy area so that the musicians don’t disturb the coral when they’re performing.”

Although holding a music festival underwater may seem a bit out there, Turner is quick to point out that it is actually achievable. “The music is obviously not as clear as when you’re sitting in room with stereo （立体音响）but you can still hear it and understand the lyrics and music,” he says. “If you were to go underwater you would recognize the song and it would sound the same. It just has little different tone to it. Plus, sound travels faster and farther underwater.”