Scientists estimate that half a billion people in the world lack sufficient water to meet their daily needs, and that number is only expected to rise with the ever-growing population and a changing climate. Therefore, researchers are working on technologies to soak up water from an abundant resource — the air. An article in Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society, describes several promising approaches.

Many water-harvesting devices are inspired by nature, Senior Correspondent Bethany Halford writes. For example, giant sequoia trees collect water from fog on their needles, which are parallel to one another. The water rolls downward and then drips to the tree’s roots. Using the same principle, researchers have developed a fog-harvesting apparatus (called a “fog harp”) with vertical parallel wires that catch microscopic droplets from the air and direct them into a water collector. Other fog-harvesting systems have been inspired by the tiny hairs on the Salsola crassa shrub, parallel grooves on rice leaves and the slippery lubricant of carnivorous pitcher plants. Read more

Why should I care about water when I can get as much as I want from my kitchen sink? That question might sound very different if you lived in Flint, Michigan or in a region of the world experiencing severe drought.

Water is everything. Actually, water is shockingly bizarre in its properties and of unsurpassed importance throughout human history, yet so mundane as to often be invisible in our daily lives. Water shaped civilization. People are increasingly aware of the intimate role that water plays in our quality of life and our relationship with society and the environment. Water Is… The Indispensability of Water in Society and Lifeexplores the ways-big and small-that water rules the world. It provides a holistic perspective on water, capturing the full breadth of the science, technology, policy, history, and future outlook for the most important substance on earth, written at a level accessible to non-experts in each of these areas. Read more

A team of scientists led by researchers from the University of Hawai’i at Mānoa School of Ocean and Earth Science and Technology (SOEST) found the first direct evidence for the surface exposed water ice in permanently shaded regions (PSRs) of the Moon.

THIS IMAGE SHOWS THE SURFACE EXPOSED WATER ICE (GREEN AND BLUE DOTS) IN THE LUNAR POLAR REGIONS OVERLAIN ON THE ANNUAL MAXIMUM TEMPERATURE (DARKER=COLDER, BRIGHTER=WARMER).

“We found that the distribution of ice on the lunar surface is very patchy, which is very different from other planetary bodies such as Mercury and Ceres where the ice is relatively pure and abundant,” said lead author Shuai Li, a postdoctoral researcher at the Hawai’i Institute of Geophysics and Planetology (HIGP) in SOEST. “The spectral features of our detected ice suggest that they were formed by slow condensation from a vapor phase either due to impact or water migration from space.” Read more

Forgot to water that plant on your desk again? It may soon be able to send out an SOS.

MIT engineers have created sensors that can be printed onto plant leaves and reveal when the plants are experiencing a water shortage. This kind of technology could not only save neglected houseplants but, more importantly, give farmers an early warning when their crops are in danger, says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and the senior author of the new study.

“This appears to be the earliest indicator of drought that we have for agricultural applications,” Strano says. “It’s hard to get this information any other way. You can put sensors into the soil, or you can do satellite imaging and mapping, but you never really know what a particular plant is detecting as the water potential.” Read more

25 researchers using radar to probe the planet’s polar ice caps have detected a lake of liquid water under the Martian ice.

It stretches 20 kilometers across, they say. The detection was made using the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on the Mars Express spacecraft. MARSIS sends radar pulses that penetrate the surface and ice caps of the planet, then measures how the radio waves propagate and reflect back to the spacecraft. Reflections off sub-surface features provide scientists with information about what lies beneath the surface. Read more