People Have Tracked Changes in Climate for Much Longer Than We Thought

Kiyoshi Miyasaki, a priest, points out some of the records on lake ice and the omiwatari, an ice ridge. His data sheet summarizing the records are on the table. Image credit:  John J. Magnuson 

Climate change may seem like a fairly new topic for scientific investigation—going back a few decades, perhaps—but a new study published in Nature Scientific Reports shows that people have been tracking changes in climate for much longer than previously thought. The study, which examined records from far northern Europe and from Japan stretching back to the 17th and 15th centuries, respectively, found that those early records—like those collected more recently—point to the same troubling conclusion: The world has been getting warmer ever since the Industrial Revolution.

In 1442, Shinto priests in the Japanese Alps started keeping track of the date on which a nearby lake froze. And in 1693, merchants in northern Finland began to track the date on which ice would break up on a local river. Taken together, these are the oldest inland water-and-ice records known.

“These are direct observations of climate, and they’re very consistent with each other,” biologist Sapna Sharma of York University in Toronto tells mental_floss.

The data from both locations can be plotted as approximately straight lines, showing only a very slow change in the freeze-date in Japan (which moved gradually earlier), and in the melting date from Finland (which moved gradually later), until the 19th century—at which point “the slope of the line changes significantly,” indicating a rise in temperatures, Sharma says.

The international team of researchers was led by Sharma and by John J. Magnuson, a limnologist (an expert on inland waters) at the University of Wisconsin in Madison. 

The Japanese data was collected by priests at Lake Suwa as part of a ceremony honoring two gods said to dwell on opposite sides of the lake. According to legend, the male god, Takeminakata, would cross the frozen waters to visit a female god, Yasakatome, at her shrine on the other side of the lake. In Finland, the freezing of Torne River was important to traders, merchants, and travelers. Record-keeping continued in both locations right up to the present, with few interruptions, Sharma says: “The Scandinavia data only has six missing years—when the Russians invaded Finland, and the record keeper had to flee.”

In Japan, the upward trend in temperature begins in the 1810s, while in Finland it begins around 1867—reflecting the later start of industrial activity in far northern Europe. “We looked at climate records, and diaries that people had kept describing the climate, and it seems to be consistent with when things started to warm up in both of those regions,” Sharma says.

In Japan, for more than 200 years, the freeze-date moved by only a tiny amount from year to year—less than one-fifth of a day per decade, on average. After the onset of industrialization, however, that rate climbs to 4.6 days per decade. The Finnish data show a comparable change.

The data are consistent with other studies of long-term climate change based on theoretical models as well as “paleo” studies (what scientists have been able to infer from sediment, ice cores, and tree rings) and from modern record keeping of ocean and air temperatures and atmospheric carbon dioxide levels, Sharma says.

The findings “provide a nice source of confirmation for other lines of evidence,” Michael Mann, an atmospheric scientist at Penn State University, who was not involved with the study, tells mental_floss. Attempts to model changes in Earth’s climate over time rely on extrapolations of modern data, so having these early records can help scientists refine their mathematical models, Mann says. This, in turn, can help us predict what may lie ahead. “The better we are able to reproduce documented past changes in climate, the more confidence we have in our projections of future, human-caused climate change using the same climate models,” he says.

An Eco-Friendly Startup Is Converting Banana Peels Into Fabric for Clothes

A new startup has found a unique way to tackle pollution while simultaneously supporting sustainable fashion. Circular Systems, a “clean-tech new materials company,” is transforming banana byproducts, pineapple leaves, sugarcane bark, and flax and hemp stalk into natural fabrics, according to Fast Company.

These five crops alone meet more than twice the global demand for fibers, and the conversion process provides farmers with an additional revenue stream, according to the company’s website. Fashion brands like H&M and Levi’s are already in talks with Circular Systems to incorporate some of these sustainable fibers into their clothes.

Additionally, Circular Systems recycles used clothing to make new fibers, and another technology called Orbital spins those textile scraps and crop byproducts together to create a durable type of yarn.

People eat about 100 billion bananas per year globally, resulting in 270 million tons of discarded peels. (Americans alone consume 3.2 billion pounds of bananas annually.) Although peels are biodegradable, they emit methane—a greenhouse gas—during decomposition. Crop burning, on the other hand, is even worse because it causes significant air pollution.

As Fast Company points out, using leaves and bark to create clothing may seem pretty groundbreaking, but 97 percent of the fibers used in clothes in 1960 were natural. Today, that figure is only 35 percent.

However, Circular Systems has joined a growing number of fashion brands and textile companies that are seeking out sustainable alternatives. Gucci has started incorporating a biodegradable material into some of its sunglasses, Bolt Threads invented a material made from mushroom filaments, and pineapple “leather” has been around for a couple of years now.

[h/t Fast Company]

Undersea Internet Cables Could Be Key to the Future of Earthquake Detection

Considering that 70 percent of the planet is covered by oceans, we don't have all that many underwater earthquake sensors. Though there's plenty of seismic activity that happens out in the middle of the ocean, most detection equipment is located on land, with the exception of a few offshore sensor projects in Japan, the U.S., and Canada.

To get better earthquake data for tremors and quakes that happen far from existing sensors, a group of scientists in the UK, Italy, and Malta suggest turning to the internet. As Science News reports, the fiber-optic cables already laid down to carry communication between continents could be repurposed as seismic sensors with the help of lasers.

The new study, detailed in a recent issue of Science, proposes beaming a laser into one end of the optical fiber, then measuring how that light changes. When the cable is disturbed by seismic shaking, the light will change.

This method, which the researchers tested during earthquakes in Italy, New Zealand, Japan, and Mexico, would allow scientists to use data from multiple undersea cables to both detect and measure earthquake activity, including pinpointing the epicenter and estimating the magnitude. They were able to sense quakes in New Zealand and Japan from a land-based fiber-optic cable in England, and measure an earthquake in the Malta Sea from an undersea cable running between Malta and Sicily that was located more than 50 miles away from the epicenter.

A map of the world's undersea cable connections with a diagram of how lasers can measure their movement
Marra et al., Science (2018)

Seismic sensors installed on the sea floor are expensive, but they can save lives: During the deadly Japanese earthquake in 2011, the country's extensive early-warning system, including underwater sensors, was able to alert people in Tokyo of the quake 90 seconds before the shaking started.

Using existing cable links that run across the ocean floor would allow scientists to collect data on earthquakes that start in the middle of the ocean that are too weak to register on land-based seismic sensors. The fact that hundreds of thousands of miles of these cables already crisscross the globe makes this method far, far cheaper to implement than installing brand-new seismic sensors at the bottom of the ocean, giving scientists potential access to data on earthquake activity throughout the world, rather than only from the select places that already have offshore sensors installed.

The researchers haven't yet studied how the laser method works on the long fiber-optic cables that run between continents, so it's not ready for the big leagues yet. But eventually, it could help bolster tsunami detection, monitor earthquakes in remote areas like the Arctic, and more.

[h/t Science News]


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