The global environmental group 350.org has issued a challenge to whoever wins the presidential election: attend the next round of UN climate talks this December in Poznań, Poland.

It's about time that the US got involved in the UN's efforts to halt global warming, says the group:

For seven years now the United States delegation at the UNFCCC meetings has been an obstructionist force stalling and blocking progress while the rest of the world has attempted to tackle the climate crisis. It would send a remarkable signal and a new wave of energy if the next US President took the initiative to re-engage with the international community on this most pressing issue. We need to remind the US Presidential candidates that there's an even bigger meltdown than the one on Wall Street, and that the world is counting on them to be part of the international solution to climate change.

To make this happen, the group has set up a page where visitors can send an email to the Obama and McCain campaigns asking each candidate to agree to attend the conference if he wins the election.

Participants of the two-week long 14th Conference of the Parties to the United Nations Framework Convention on Climate Change, or COP 14,  will work toward drafting a successor agreement to the Kyoto Protocol, the system of mandatory carbon caps that are set to expire in 2012. The United States is the only industrialized country that has not signed the protocol.

Writing in Grist, author and 350.org cofounder Bill McKibben, argues that American participation in the talks is crucial.

[E]ither Barack Obama or John McCain will need to reengage the United States in the international process for reaching a global agreement on climate change. If we don't, we can cut as much as we like out of our carbon emissions and it won't do much to slow the planet's warming. Even as the financial markets struggle, we have the capital and the technology to make a crucial difference. After all, Americans are the biggest per capita polluters of all, but we've played no role in the global climate talks over the last eight years. That must end. Rajendra Pachauri, the head of the Intergovernmental Panel on Climate Change, said last year that we have until 2012 to make huge changes as a planet or it will be too late.

McKibben helped launched 350.org in March to highlight what he often calls "the most important number on the planet," that is, the maximum safe ratio, in parts per million, of carbon dioxide atoms in the atmosphere. Leading scientists say that CO2 concentrations higher than 350 ppm put us at risk for catastrophic climate change. Current atmospheric concentrations are at 387 ppm and rising.

The group released a brilliant animation in June to highlight the issue (the spot was produced by Free Range Studios, which also produced The Story of Stuff, which is well worth watching if you have 20 minutes.)

The group also put together a video about thier invitation, which you can watch here: