Answer questions like ...
- The graph to the left, called the Keeling curve, maps the overall rise in atmospheric carbon dioxide since 1958. But why does it have a zig-zag shape, showing cyclical rises and falls in carbon dioxide levels?
- In the 10,000 years before the Industrial Revolution in 1751, carbon dioxide levels rose less than 6 percent. Since then, they've risen by:
- The average American adds how much carbon dioxide to the atmosphere per year?
- Climate scientists predict that increasing carbon dioxide levels in the atmosphere will result in:
- Which planets have carbon dioxide in their atmosphere?