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.