This weekend, the world heads to Copenhagen to try and come up with a global strategy to combat climate change. The sessions formally open Monday, but already there are developments that suggest what seemed impossible just three weeks ago, may come true by Dec.18 when the U.N. conference closes.
President Barack Obama originally planned to go to the conference on his way to pick up the Nobel Peace Prize in Norway on Dec. 10. But, in an interesting move, he changed his schedule to come on Dec. 18, the last day of the conference, where he will join a host of world leaders.
The White House says the reason for the schedule change is due to "progress being made towards a meaningful Copenhagen accord."
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Offers of compromise from certain countries have prompted others to step up to the table. Obama said the United States is willing to commit to cutting its carbon emissions "in a range" of 17 percent by 2020. In turn, China and India have pledged to reduce their "carbon intensity" as they continue to grow economically. And the European Union is talking about boosting its promise to cut emissions from 20 to 30 percent by 2020. Japan also says it can slash its emissions by 25 percent.
But cutting emissions is not the only issue facing negotiators. Here's a quick guide to some of the other thorny issues.
A jump start for developing nations
The world's developing nations are adamant that they should not have to pay for the sins of already industrialized nations. They say they need to continue to grow their economies to lift their people out of poverty – even if it means doing so in less than environmentally progressive ways.
But many of these countries are on the front line of climate change and are already dealing with drought or sea level rise. They want aid money so they can buy the technology needed to adapt to what's already happening.
The White House says there is an emerging consensus to try to provide $10 billion a year by 2012 for these underdeveloped nations. It says America is willing to pay its fair share and that other countries will make substantial contributions, too.
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Cutting down the world's rainforests puts more carbon emissions in the air than all the cars, trucks, trains and planes in the world. Not only that, but it robs the Earth of one of its great carbon storage systems – the plants, trees and soil in the rainforest.
So there is a lot of talk about reforestation, planting trees to return land to the way nature intended. It is the cheapest and easiest way to combat climate change.
How is it done? For two decades, Costa Rica has paid landowners to maintain their forests or replant forests. As a result, the country's forest cover has grown from 21 percent to more than 50 percent.
And Brazil says it is willing to preserve its spectacular Amazon rainforest, but it wants to be paid to do so. The objective, more forests, is easy to agree on. The tougher issue is deciding who should pay for it.
The United States
At the Bali conference on climate change two years ago, the U.S. was told to lead or get out of the way. Now, the offer from the U.S. to reduce emissions by around 17 percent has prompted China and India to promise to take action as well.
But critics say it is not enough and that the U.S. must do more. Some see Copenhagen as a test of U.S. leadership in the world. However, any agreements made in Copenhagen will have to face domestic scrutiny as well. What the world wants may not be what the Senate is willing to pass – and the Senate will have to approve any climate treaty.
There are many more issues. We will be talking about them over the next two weeks. It should be a very exciting time.