| You can tell the age of a tree by counting its rings, but these records of a tree's life really say a lot more. Scientists are using tree rings to learn what's being happening on the sun's surface for the last ten thousand years. Each ring represents a year of growth. As the tree grows, it adds a layer to its trunk taking up chemical elements from the air. By looking up the elements in the rings for a given year, scientists can tell what elements were in the air that year. Doctor Stevenson is analyzing one element —— carbon-14 in ring from both living and dead trees. Some of the rings go back almost ten thousand years to the end of the Ice Age. |
| You can tell the age of a tree by counting its rings, but these records of a tree' s life really say a lot more. Scientists are using tree rings to learn what' s being happening on the sun' s surface for the last ten thousand years. Each ring represents a year of growth. As the tree grows, it adds a layer to its trunk taking up chemical elements from the air. By looking up the elements in the rings for a given year, scientists can tell what elements were in the air that year. Doctor Stevenson is analyzing one element carbon14 in ring from both living and dead trees. Some of the rings go back almost ten thousand years to the end of the Ice Age. |
| You can tell the age of a tree by counting its rings, but these records of a tree' s life really say a lot more. Scientists are using tree rings to learn what' s being happening on the sun' s surface for the last ten thousand years. Each ring represents a year of growth. As the tree grows, it adds a layer to its trunk taking up chemical elements from the air. By looking up the elements in the rings for a given year, scientists can tell what elements were in the air that year. Doctor Stevenson is analyzing one element carbon14 in ring from both living and dead trees. Some of the rings go back almost ten thousand years to the end of the Ice Age. |
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