Scientists have compiled the first map detailing the height of forests worldwide, an inventory they hope will provide new insights into global carbon storage. The map — compiled from data collected over seven years using NASA satellite laser technology that can measure vertical “slices” of different tree heights in forests — shows that the tallest forests on Earth are in the Pacific Northwest of North America and across parts of Southeast Asia. Shorter forests predominate across northern Canada and Eurasia.
The tallest canopies are found in temperate conifer forests, which include Douglas fir, redwoods, and sequoias, and can easily reach 131 feet (40 meters) in height; some California redwoods are more than 300 feet tall. In contrast, boreal forests — which include spruce, fir, larch, and pine — have canopies that are typically less than 66 feet. NASA scientists hope the map will help them determine how much of the world’s carbon is stored in forests; which types of forest absorb more carbon than others; where some 2 billion tons of “missing” carbon released by humans annually ends up; and how well the planet can continue to absorb rising CO2 emissions.