字幕表 動画を再生する 英語字幕をプリント Architects are constructing wooden skyscrapers and transforming high rises into living gardens. And these designs...could go a long way in improving how we live in the future. Skyscrapers are symbols of modern ambition. But the race to be the tallest is fueled by steel and concrete, two materials that account for an estimated 8% of global C02 emissions. Two countries in particular - Singapore and Canada - are attempting to transform the urban skyline. In Singapore, engineering firms like WOHA are coating their buildings with lush, native plants. “To deal with high densities in cities, particularly Singapore where we are land-limited, it is actually important to bring landscape greenery and nature very close to where people alive and interact.” Aside from the aesthetics of this building, these towers of green are also helping to bring biodiversity back to our urban centers. Because this building has vertical gardens integrated into its design, it actually contains 1000 percent more plant life than could have existed on the original plot of land. And having buildings that integrate nature in this way within our dense cities could have a measurable impact on quality of life and the quality of the environment. Some of us may have experienced New York in the summertime. One of the reasons why we get a heat build up in cities like this is a process known as Insolation. When the sun hits a concrete skyscraper, heat is stored within the building and then re-radiated back into the environment causing the air temperature to rise. However, when WOHA designed the Oasia Hotel, they used plants to combat this problem. “In our projects, we have always tried to aim for more than 100% green replacement. We need to find plants that can handle not just the wind, but maybe also need to be quite hardy as well. Tropical high-rise building skyscraper, when you elevate it, you actually get nice breezes and nice wind. And that actually makes it very comfortable. There's no reason why, I think, when we have high density in the city that we should forget about gardens, parks, and nature. In Canada, architects and engineers are piloting new designs out of a familiar material: wood. “Wood is clearly an advantageous material, because it requires much less resources to be extracted from the forest. It requires less resources to transport on site. It allows for faster construction.” To construct a wooden skyscraper, engineers use mass timber, which is engineered to handle loads similar to concrete and steel. “Wood has a very, very favorable strength to weight ratio. Compared to how heavy it is, it is almost as strong as steel.” They'll use a technique called cross-laminated timber, where different layers of wood are glued together in a cross-based orientation. Wood isn't a new material by any stretch. It has ancient roots in medieval European churches and temples in Japan. But it has had a major historical drawback. Fire. Urban cities were wiped out in the early 19th century, and steel and concrete eventually became the dominant building materials. But mass timber today doesn't ignite as easily. “All these structural wood elements, that need to be protected from fire, they're encapsulated in drywall. These elements cannot burn anymore, and they're just as safe as if it were a concrete structure.” And wooden buildings have huge environmental benefits too. In all of Canada, the U.S., Europe, the amount of wood growing is significantly larger than the amount of wood that is actually harvested. If we harvest our trees and put them in structures, we actually give an incentive to reforest more areas, and regrow more trees. This trend has spread to countries like the U.K., and Japan, kickstarting the next race for the tallest timber tower. By 2050, there will be nearly 10 billion people living on this planet, and two-thirds of us will be in cities. To handle the rise of human population and global temperature, native plant designs and timber skyscrapers could go a long way in curbing environmental and economic impacts. And they'll make us feel better too. For more science documentaries, check out this one right. Don't forget to subscribe and keep coming back to Seeker for more videos.