字幕列表 影片播放 列印英文字幕 Cacti and desert beetles can live in arid environments because they’ve adapted to suck water out of the air. So, can we do that if we’re in a drought? Hi guys, Amy here for DNews. We know the Earth’s climate is warming from a mix of natural changes, including solar activity, and man-made causes, namely greenhouse gases and aerosols. This is taking a toll on global weather. There is more water vapour in the atmosphere so rainfall is increasing in tropical areas, but drier areas are experiencing some of the worst droughts in history. The thing is, even in deserts, there's humidity in the air. So, to help tackle the world's drought problems, a team of scientists from Harvard, with support from the Department of Energy, looked to plants and insects that are able to pull water out of the air to survive in the desert. This biologically-inspired technology described in the journal Nature involves collecting water from air by condensing water vapor on surfaces inspired by beetles, cacti and other desert-dwelling organisms. They looked at the bumpy surfaces of desert beetles’ shells and found that, if the geometry is right, water droplets grow faster on the tops of convex bumps than on a raised flat surface of the same height. They looked at the asymmetric structure of cactus spines and found they had the best topography to guide the condensation off the bumps to be collected. And, the slippery surface of carnivorous pitcher plants inspired the researches to guide those formed water droplets down a smooth, non-stick surface. The team combined these elements with a material that repels liquid called Slippery Liquid-Infused Porous Surfaces technology or SLIPS. The three nature-inspired inventions combined with the SLIPS technology make an excellent collector to gather water from the air! When set up, any atmospheric moisture pools on the bumps and flows as water droplets down the asymmetrically pitted water-repellant surface! But could it make a difference? I asked the paper’s lead author Kenneth Park. He roughly calculates that the volume of air the size of a house in a desert holds about 16 liters of water. That’s not a lot for people in developed countries, but in desert regions it could be life changing access to drinking and cooking water. And of course in humid areas, that number rises even more. Basically, as long as surface temperature gets below the dew point, there will be condensation to harness from the air. The challenge now facing the team is controlling the size of the water droplets and the direction in which they flow. But with the details worked out, this could be a step towards developing a passive system capable of collecting and transporting atmospheric water to a reservoir. But remember, while this technology is great, it’s a proof of concept. We still need to conserve resources, especially those of us living in areas affected by drought, like California, which is experiencing the worst drought in more than a century. So with scientists developing these kinds of technologies, just how serious is the global drought that we’re looking to thin air as a water source? Julia’s got the information on this current crisis in this episode right here. Some people are creeped out drinking recycled water… would you feel weird drinking water pulled from the air? Let us know in the comments and don’t forget to subscribe so you never miss an episode of DNews.