CLOSE
Original image
Debasish Ghosh, Wikimedia Commons // CC BY-NC-ND 2.0

Heat Waves Could Make South Asia Unlivable by 2100

Original image
Debasish Ghosh, Wikimedia Commons // CC BY-NC-ND 2.0

Scientists say increasing greenhouse gas emissions in densely populated parts of South Asia will push temperatures past the "upper limit on human survivability." They published their findings in the journal Science Advances.

The human body can only withstand so much heat, and the authors of the current paper note that 35°C (95°F) pushes that upper limit. Anything above that will result in death "even for the fittest of humans under shaded, well-ventilated conditions."

This 95°F maximum is what's called a wet bulb (TW) measurement. Like the heat index, TW considers humidity as well as air temperature, which means it's a more accurate measurement of how well our bodies can naturally cool themselves down. The muggier the climate, the higher the TW. And in places like India, the TW is pretty darn high.

The research team combined climate data from Pakistan, Nepal, India, Bangladesh, and Sri Lanka with information about current and estimated future greenhouse gas emissions in those countries.

With these combined data points, they created two possible scenarios: the "business as usual" model, in which the region's rapidly growing economy continues to produce more and more air pollution; and the "mitigation" model, in which something is done to slow, if not stop, emissions.

Neither outcome looked particularly good, but there was a big difference between them. The business-as-usual model indicated that average temperatures will easily reach TW 95°F by the year 2100. For the mitigation model, that number was closer to TW 88°F.

Heat map of India projecting temperatures from 1975 to 2100.
Historic and projected temperatures from 1975 (L) to 2100 (R).
Im et al. 2017. Science Advances.

These were just the total averages. Some regions were far worse off than others. In either situation, poorer agricultural communities in India will be hit the hardest—a particularly dangerous outcome in areas where most people live without air conditioning.

"This disparity raises important environmental justice questions beyond the scope of this study," the authors write. "The findings … may present a significant dilemma for India because the continuation of this current trajectory of rising emissions will likely impose significant added human health risks to some of its most vulnerable populations."

Original image
arrow
science
11-Year-Old Creates a Better Way to Test for Lead in Water
Original image

In the wake of the water crisis in Flint, Michigan, a Colorado middle schooler has invented a better way to test lead levels in water, as The Cut reports.

Gitanjali Rao, an 11-year-old seventh grader in Lone Tree, Colorado just won the 2017 Discovery Education 3M Young Scientist Challenge, taking home $25,000 for the water-quality testing device she invented, called Tethys.

Rao was inspired to create the device after watching Flint's water crisis unfold over the last few years. In 2014, after the city of Flint cut costs by switching water sources used for its tap water and failed to treat it properly, lead levels in the city's water skyrocketed. By 2015, researchers testing the water found that 40 percent of homes in the city had elevated lead levels in their water, and recommended the state declare Flint's water unsafe for drinking or cooking. In December of that year, the city declared a state of emergency. Researchers have found that the lead-poisoned water resulted in a "horrifyingly large" impact on fetal death rates as well as leading to a Legionnaires' disease outbreak that killed 12 people.

A close-up of the Tethys device

Rao's parents are engineers, and she watched them as they tried to test the lead in their own house, experiencing firsthand how complicated it could be. She spotted news of a cutting-edge technology for detecting hazardous substances on MIT's engineering department website (which she checks regularly just to see "if there's anything new," as ABC News reports) then set to work creating Tethys. The device works with carbon nanotube sensors to detect lead levels faster than other current techniques, sending the results to a smartphone app.

As one of 10 finalists for the Young Scientist Challenge, Rao spent the summer working with a 3M scientist to refine her device, then presented the prototype to a panel of judges from 3M and schools across the country.

The contamination crisis in Flint is still ongoing, and Rao's invention could have a significant impact. In March 2017, Flint officials cautioned that it could be as long as two more years until the city's tap water will be safe enough to drink without filtering. The state of Michigan now plans to replace water pipes leading to 18,000 households by 2020. Until then, residents using water filters could use a device like Tethys to make sure the water they're drinking is safe. Rao plans to put most of the $25,000 prize money back into her project with the hopes of making the device commercially available.

[h/t The Cut]

All images by Andy King, courtesy of the Discovery Education 3M Young Scientist Challenge.

Original image
iStock
arrow
Weird
Switzerland Flushes $1.8 Million in Gold Down the Sewer Every Year
Original image
iStock

Switzerland has some pretty valuable sewer systems. As Bloomberg reports, scientists have discovered around $1.8 million worth of gold in the country's wastewater, along with $1.7 million worth of silver.

Scientists at the Swiss Federal Institute of Aquatic Science and Technology examined sewage sludge and effluents, or discharged liquid waste, from 64 water treatment plants and major Swiss rivers. They did this to assess the concentrations of various trace elements, which are "increasingly widely used in the high-tech and medical sectors," the scientists explained in a press statement. "While the ultimate fate of the various elements has been little studied to date, a large proportion is known to enter wastewater."

The study, which was recently published online in the journal Environmental Science & Technology, revealed that around 94 pounds of gold makes its way through Switzerland's sewage system each year, along with 6600 pounds of silver and high concentrations of rare metals like gadolinium and niobium. For the most part, these metals don't harm the environment, researchers say.

With gold and silver quite literally flowing through their sewers, is there any way that Switzerland could turn their wastewater into wealth? Scientists are skeptical: "The recovery of metals from wastewater or sludge is scarcely worthwhile at present, either financially or in terms of the amounts which could be extracted," the release explains.

However, in the southern canton of Ticino, which is home to several gold refineries, the "concentrations of gold in sewage sludge are sufficiently high for recovery to be potentially worthwhile," they conclude.

Switzerland is famous for its chocolate, watches, and mountains, but it's also home to major gold refineries. On average, around 70 percent of the world's gold passes through Switzerland every year—and judging from the looks of it, much of it goes down the drain. As for the sewer silver, it's a byproduct of the chemical and pharmaceutical industry, which is a cornerstone of Switzerland's economy.

[h/t Bloomberg]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios