What's happening?

Here's your host: Al Gore is keen to tackle climate change.Live Earth, LLC

Al Gore is continuing his crusade to tackle climate change by hosting a 24-hour, seven-continent mega-concert. On 7 July, starting from 02:10 London time, bands will belt out songs from (in order) Sydney, Tokyo, Shanghai, Hamburg, London, Johannesburg, New York, Rio de Janeiro and, although this bit won't be live for logistical reasons, the Antarctic. Some other venues are also hosting shows, including Kyoto — home of the agreement to try to reduce greenhouse-gas emissions.

What's the point?

To raise awareness about climate change, and what can be done about it. The music itself might have little to do with that, but political speeches will probably be interspersed with performance, and the vast media coverage (and Live Earth website) contain some weightier discussions of the issue (and some lighter discussions too, including a list of greensex_guide.aspx">climate-friendly ways to heat up your love life).

Critics argue that the world is already aware of climate change, and that the concerts don't have the clear-cut aims that have fuelled success at similar events in the past. Live Aid raised money to feed the starving and Live 8 was an attempt to influence a specific political event, the Gleneagles G8 summit.

Live Earth tries to convince everyone to be a bit more aware and do a bit more about it — from leaving the tap off while brushing their teeth, to turning down the thermostat by 1 degree . Such actions will be impossible to properly quantify and so the success of the event hard to judge.

How's it going?

In the United Kingdom there's a fair amount of media coverage. But the BBC reports that many other venues are having a hard time selling all their tickets, with indifference where the promoters hoped for buzz. An Istanbul concert event has been cancelled due to lack of interest.

Logistical difficulties have cropped up. In South Africa the concert was originally slated for the World Heritage Site the Cradle of Humankind near Johannesburg but had to be moved. Security concerns in Brazil, where the outdoor concert is slated to be free of charge, caused the courts to call for a cancellation of the show — which they later rescinded. And the Antarctic 'venue' of a research station doesn't have the broadband capacity to stream their concert to the world live — it has been recorded in advance (see 'The great gig in the South ').

Won't this whole thing use up a lot of the planet's resources?

Unfortunately, yes — but the organizers are trying to make sure that it is less profligate than other events on this scale. Burgers in London will be sold in biodegradable starch containers, for example, and Sydney's concert tickets come with free public transportation. These may look like token gestures, but the concerts are all about the idea that every little bit makes a difference.

John Rego, environmental adviser for the eight live concerts, has said that comparable events in the past have produce 3,000-4,000 tonnes of carbon dioxide per venue, and that Live Earth hopes to do at least 25% better.

The electricity to power the concerts, he says, will come from renewable sources, including biodiesel (which is not perfectly 'green' — see 'Biofuels get mixed review'). Four thousand tonnes is the amount of carbon dioxide put out by about 200 average Americans over the course of a year.

So is the whole event 'carbon neutral'?

Rego has said that greenhouse gases spewed out by stars' jets or by the audience's travel will be offset. But calculating how much carbon one is guilty of emitting for such a huge event is nearly impossible, and different 'greening' companies try to make amends for emissions in different ways — some more certain than others (see 'Climate credits').

One of the Japanese bands has offered to plant trees to offset its emissions, for example — a fairly dubious means of offsetting, since it isn't clear how much carbon forests permanently store away. Rego is working with a number of different greening consultants, including the independent, nonprofit organization Climate Group.

Where will the money go?

Net proceeds from the events will go to the Gore-founded Alliance for Climate Protection , the stated mission of which is to "persuade the American people — and people elsewhere in the world — of the importance and urgency of adopting and implementing effective and comprehensive solutions for the climate crisis." Their money goes towards education campaigns and political petitioning.

How can I watch?

Live Earth concerts will be streamed live at www.LiveEarth.MSN.com.

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