Cape Town switches off for Earth Hour and the environment.

Show you care by turning off your lights from 20:30 to 21:30 on 31 March for Earth Hour 20012

All Cape Town residents and visitors are encouraged to participate in Earth Hour on Saturday 31 March 2012 by switching off all lights for one hour, between 20:30 and 21:30.

This is what went down in Cape Town for Earth Hour Events in Cape Town 2010.

Earth Hour is a World Wide Fund for Nature (WWF) initiative – and this symbolic act aims to create awareness that climate change threatens lives, livelihoods, and lifestyles, and galvanise support to pressure governments to combat climate change.

Climate change is the most pressing environmental, social and economic problem facing the planet. Climate change is how the average weather of our planet varies over time.

Global warming means that the average temperature on the Earth’s surface is rising. Carbon dioxide levels are higher than at any time in the past 650 000 years. This is caused by human activities such as the burning of fossil fuels (oil, gas and coal).

Other human factors affecting climate change include the destruction of forests (deforestation). Forests are important as they help to naturally remove carbon dioxide and other polluting gases from the air.

The ten warmest years on record have all occurred since 1990. If we do not stand together and act now to tackle climate change, the world will reach a critical 'tipping point' beyond which really dangerous climate change will become unstoppable.

We must take steps now to try and prevent further climate change rather than mitigate its effects later – when it is already too late.

Earth Hour started in 2007 in Sydney, Australia with 2.2 million homes and businesses turning their lights off for one hour.

By 2008 this event had become a global sustainability movement with up to 50 million people across 35 countries participating.

Global landmarks such as the Golden Gate Bridge in San Francisco, Rome’s Colosseum and the Coca Cola billboard in Times Square, all stood in darkness, as symbols of hope for a cause that grows more urgent by the hour.

Already 377 cities and 64 countries are committed for the 2009 event. This number grows every day as people realise how such a simple act, can have such a profound result in affecting change.

Cities have a central role to play in tackling climate change, particularly as cities bear a disproportional responsibility for causing it.

In fact, cities consume 75 percent of the world's energy and produce 80 percent of its greenhouse gas emissions. That is why it is so important for cities to work together, set the agenda on this issue and show leadership on this issue.

In South Africa, Archbishop Desmond Tutu has honoured WWF by agreeing to be the patron of Earth Hour 2009, and Executive Mayor Helen Zille has also pledged her support.

To demonstrate South Africa’s commitment to the rest of the world, Cape Town will switch off the lights that illuminate Table Mountain.

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