There is nothing like a coast redwood. It is the planet's tallest tree, up to heights of more than 320 feet into the sky. With trunks that grow to more than 27 feet wide, they can live for over 2,000 years. Some of them living today were alive during the time of the Roman Empire.
Coast redwoods have survived through thousands of years of natural floods, droughts, tsunamis and fires. They can thrive and recover from damage as long as they can count on rainwater and coastal fog banks that roll in every morning. And it is those critical water sources that are disappearing as temperatures continue to rise. The damp conditions the trees like are rarer than they used to be. Coast redwoods now occupy less than 10 percent of their original range.
Their loss will have some consequences, paricularly in the vast amount of carbon they store. Redwoods can store 2,600 metric tons of carbon per hectare, more than double the absorption rate of the Pacific Northwest's conifer trees (针叶树)，according to a new research published in Forest Ecology and Management.
David Milarch, an arborist from Michigan, says he feels sorrowful about the disappearing redwoods. He spends his days tracking down the healthiest coast redwood specimens (样本) he can find, cloning them in his own lab, and then planting them in carefully chosen places where they can thrive. Milarch's goal is both to strengthen the coast redwood gene pool with clones of the strongest individuals, and to store loads of carbon. It's a complicated mission with a simple philosophy: save the big trees, and they'll save us.
Milarch explains that we need a practical and measurable solution to fighting against climate change. He believes the redwoods are the answer. However, scientist Mark Maslin cautions against viewing tree planting as a magic bullet, since even fast-growing trees take a long time to grow and be mature enough to reach their maximum carbon-trapping time which climate change cannot afford. As a global society, the most important thing we should do now is to reduce our overall carbon emissions(碳排放) if we want to have any impact on the planet's climate crisis(危机).
