Archive for February 17, 2017

A Plea for the Water in All We Use, Make and Eat

“We’re using tomorrow’s water to meet today’s food demand,” warned Sandra Postel, National Geographic Freshwater Fellow, helping to provoke a meaningful discussion on water as it relates to food at the Aspen Environmental Forum. Agriculture was a central theme as it consumes a disproportionate share of global water resources.

Jon Foley from the University of Minnesota painted a picture of our inefficiency. “One liter of water is needed to irrigate one calorie food, but that changes by factor of 100 for the most inefficient practices.” It is clear that water efficiency improvements for agriculture must play a large role. Read more

Fuel cell lantern ditches batteries for salt water

For many people, camping/emergency lanterns are one of those things that may sit for months without being used, only to have dead batteries when they’re finally needed again. While solar-powered lanterns are one alternative, they do still need to sit in the sunlight for a few hours in order to charge. That’s where Hydra-Light’s PL-500 comes in. It’s a fuel cell-powered lantern that’s ready to shine as soon as it receives some salt water.

The PL(Personal Lantern)-500 features 16 LEDs, along with a USB outlet for charging devices such as smartphones. It also comes with a palm-sized 3-LED Accessory Light, which can be plugged into and powered by a 2.5-mm outlet on the main lantern, via a 30-ft (9-m) power cord. Read more

Scientists accidentally create nanorods that harvest water from the air

Researchers have accidentally created nanorods that can absorb water at low humidity and expel it as the humidity increases
Learning from your mistakes is a key life lesson, and it’s one that researchers at Pacific Northwest National Laboratory (PNNL) can attest to. After unintentionally creating carbon-rich nanorods, the team realized its accidental invention behaves weirdly with water, demonstrating a 20-year old theory and potentially paving the way to low-energy water harvesting systems and sweat-removing fabrics.

Researchers have accidentally created nanorods that can absorb water at low humidity and expel it as the humidity increases

The researchers note that ordinarily materials will absorb more water as the humidity in the air around them increases. But between 50 and 80 percent relative humidity, these nanorods will actually do the opposite and expel water, a behavior they say is not shared by any other material. Below that range, they behave as normal, so the process is reversible by lowering the humidity again. Read more

Bizarre fourth state of water discovered

You already know that water can have three states of matter: solid, liquid and gas. But scientists at the Oak Ridge National Lab (ORNL) have discovered that when it’s put under extreme pressure in small spaces, the life-giving liquid can exhibit a strange fourth state known as tunneling.

A sample of beryl and an illustration that shows the strange shape water molecules take when found in the mineral’s cage-like channels

The water under question was found in super-small six-sided channels in the mineral beryl, which forms the basis for the gems aquamarine and emerald. The channels measure only about five atoms across and function basically as cages that can each trap one water molecule. What the researchers found was that in this incredibly tight space, the water molecule exhibited a characteristic usually only seen at the much smaller quantum level, called tunneling. Read more

Billions of People Got Clean Water in the Past 25 Years

A new graphic shows where access to safe drinking water has gotten better—or worse.

Around the world, 663 million people don’t have access to clean drinking water. That’s about nine percent of the world’s population.

The reasons for this range from lack of plumbing—as with tropical villages built into mountains to escape heat—to the sheer distance many people live from reliable water sources. Further, shifts in the weather—some thought to be related to climate change—have brought droughts in some areas and flooding in others: Natural disasters like this can wreck the water table.

The numbers aren’t as bad as they once were, though. In 2000, the United Nations set out to halve the number of people without access to water sources that are protected from contamination, called “improved water.” It met the target in 2010.  Read more