Leading climate change experts discuss one of the most complex scinetific puzzles ever to confront humankind. How do we know the earth is warming? How do we know the warming is caused by rising levels of carbon dioxide? How close are we to having all the answers?
The Carbon Cycle Much of the carbon we are burning is not staying in the atmosphere. What's happening? Where does the carbon in the atmosphere come from? How does carbon get into the oceans, and how much is in there? Is the oceans' ability to absorb carbon decreasing? How will increased amounts of carbon affect plants and animals? Plants need nitrogen. Can they get enough to meet the increased levels of carbon dioxide? What will increased carbon do to life in the oceans? Are there surprises in the carbon cycle that could lessen climate warming or make it much worse? Is there a carbon tipping point after which climate change consequences will become dire?