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10 Lakes That Are Disappearing or Already Gone

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NASA

One hundred billion gallons of water don’t just go missing overnight. In the past, it took decades for man-made water diversion projects and changes in climate to dramatically reduce the size of some of the world’s largest bodies of water. Today, water around the globe is disappearing faster than ever. Here are ten bodies of water that are already dry, or disappearing at an unprecedented rate.

1. Owens Lake, United States

The unquenchable thirst of Los Angeles is to blame for the dust bowl now known as Owens Valley. Before drying up in 1926, Owens Lake covered about 108 square miles in California near the border with Nevada. But in 1913, the Los Angeles Department of Water and Power diverted the Owens River into the LA Aqueduct. One hundred years later, the City of Los Angeles has paid more than $1.2 billion to minimize the adverse health effects of the windblown dust coming off the dried lake bed. The DWP uses a combination of gravel and flora cover, plus flooding of about 42 square miles of the valley to keep airborne pollution to a minimum. But the DWP, along with local agriculture and livestock representatives, are unsatisfied with the wasted water that goes toward the flooding. This spring, the agency announced it would work with local agencies to craft a long-term solution to dust mitigation that relies less on water.

2. Aral Sea, Kazakhstan

NASA

Once an oasis in central Asia and the fourth largest body of fresh water in the world, the Aral Sea began losing volume in the 1960s. In an attempt to irrigate crops in the deserts of what is now Uzbekistan, the USSR had started diverting water from the Aral’s feeder rivers, the Amu Darya and Syr Darya, in the '40s. By 1986, the lake volume decreased to the point of becoming four distinct bodies of water. Today, it can claim only about 10 percent of its former surface area of 26,300 square miles. By volume, the lake has lost an estimated 167 billion gallons of water, more than the entire volume of Lake Erie.

Still, there is some hope the Aral Sea will persist—though at nowhere near the lake’s historic levels. In 2003, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan joined together to build the Kokaral Dam. By 2007, the structure had slowed the drainage enough to increase water levels in the northern body by about 40 meters.

3. Dead Sea, Middle East

NASA

At the lowest point on Earth, the Dead Sea is slowly wasting away. Although a one-inch drop in the lake level from evaporation on a hot summer day is normal, the last 30 years have seen a dramatic decrease in lake size. Recently, water levels have been dropping as quickly as 3 feet per year. Two distinct bodies of water now characterize the Dead Sea. The southern portion is home to ponds that are used to extract salts and other minerals, while the northern body is still a beacon for tourists.

To stem the disappearance of the Dead Sea, Israel, Jordan, and Palestine have agreed to a plan to pump in about 53 billion gallons of water per year from the Red Sea, which is more than 100 miles away.

4. Lake Faguibine, Mali

NASA

In its heartier days, Lake Faguibine in Mali was one of the largest lakes in West Africa, at about 230 square miles. Fed by the Niger River, the ecosystem supported a healthy economy of fishing, agriculture, and livestock herding. But by 1990, droughts had completely dried the lake, forcing residents to seek subsistence from other resources. A return of rains in the last 15 years has added about six percent of former surface area to Faguibine, but long-term restoration appears impossible.

5. Lake Assal, Djibouti

UNEP

With temperatures reaching a scorching 125 degrees Fahrenheit during the summer, the evaporation of Lake Assal in Djibouti is an unavoidable reality. Housed in a volcanic crater, the body of water was likely separated from the Gulf of Aden, and the greater Indian Ocean, by lava flows. In such harsh conditions, Assal sees little rainfall runoff to feed the lake. Instead, its volume is replenished through subsurface water flow from the nearby gulf.

One of just a few lakes that has not shrunk due to water diversion, Assal is still an important natural resource for the local economy. The lake is 10 times more saline than seawater, and its salt is harvested for distribution across Africa and Europe.

6. Lake Chad, Chad/Niger/Nigeria/Cameroon

NASA

The Lake Chad basin in central Africa is one of the most dusty places on earth, and a “ecological catastrophe” according to the United Nations. Like the Aral Sea, the lake’s main feeder, the Chari River, was diverted to provide irrigation for farmers in different regions. Between 1963 and 2001, the lake shrank by 95 percent to just 580 square miles; it had previously measured more than 10,000 square miles. With the lack of water and marshes, dust chokes the area, beginning the process of dune formation and the desertification of a once lush habitat.

Replenishment plans are ambitious, but still in the early phases. The nations of Chad, Nigeria, Cameroon, Niger, and the Central African Republic (which is home to a number of Chari River tributaries) hope to pump water from the Congo River north toward the Chari. Although the Congo dumps water into the Atlantic Ocean, the effects of diversion toward Chad remain unclear.

7. Lake Urmia, Iran

UNEP

With six dams capturing a majority of water from 11 rivers that once fed the salt lake, Lake Urmia in northern Iran is evolving from a luxury vacation destination into a cracked salt bed. As big as 2,000 square miles, the lake was once among the largest in the Middle East. Today, it covers just under 40 percent of that area. Although energy and food production has benefited from the damming of the rivers, many environmentalists fear the long-term result of water diversion could be a nearly dry lakebed like the dustbowl of the Aral Sea.

8. Poyang Lake, China

NASA

This past January, China’s Lake Poyang receded far enough to reveal an ancient stone bridge that had been submerged for 400 years. But excitement over the discovery has been tempered by continuing concerns over the extremely low water levels of the country’s largest freshwater lake. In 2012, during one of the country’s worst droughts, China’s official Xihua News Agency reported the lake had reached a new record low of 7.95 meters (about 28 feet). Local authorities at that time even went to the extreme measure of air-dropping millet, corn, and shrimp for the hundreds of thousands of migratory birds that feed at Poyang. And while mother nature is one of the main culprits, China’s disastrous Three Gorges Dam has also played a big role in withholding water from the lake.

Damming the lake, which is situated in the middle of the Yangtze River, has been proposed to restore lake levels for both economic and ecological benefits—but no imminent plans are in place, as the effects of the drought are forgotten during the wet season. 

9. Lake Chapala, Mexico

NASA

Since the time of the Spanish conquistadors, Mexico’s lakes have suffered dramatic upheaval. Once a pristine lake, the capital was created by draining and then building out Mexico City. Now the fate of Mexico’s largest lake, Chapala, may mimic that of the capital. Historically averaging about 700 square miles in surface area, Chapala experienced its first major crisis in 1955. A combination of drought and diversion saw the water level dip by about 7 percent, enough to wreak havoc on hydraulic electricity generation for the town of Guadalajara. Although the lake rebounded throughout the later part of the century, by 2001 more than 25 percent of the lake’s surface area had disappeared. Water levels nearly matched those of the crisis in 1955.

Faced with additional uncertainty about water availability, in March a presidential decree set strict limits on the amount of water that can be diverted from both Lake Chapala and its watershed. Enforcement of the limits will be the next test.

10. Great Lakes, United States/Canada

NOAA

Staring across the vast expanse of Lake Michigan, it could be hard to recognize the signs of trouble. But last year, the Great Lakes reached their lowest levels in recorded history. With a 1.5-foot average drop in water level across the connected Lakes Michigan and Huron since 1999, 2.5 million gallons have exited the body of water. The main culprit for the receding lake level is the St. Clair River, a waterway that has been widened and deepened numerous times in the last century to provide a shipping channel between the upper and lower Great Lakes. The cumulative effect of human engineering and mother nature’s power is an oversized drain spout at the bottom of Huron.

To avoid such a fate, the Army Corps of Engineers designed remediation measures in the 1960s during the last deepening. But bureaucracy and above-average water levels hindered any action on the structures. After years of agitation on the subject, groups like Restore our Water International have reignited the drive for remediation. In March, President Obama allocated funding toward re-evaluating the Corps’ plans. Other attempts are being made to keep attention on the topic while the evaluation takes place. The documentary Drain, which is currently in production, examines the current crisis at the Great Lakes, and the lessons learned from other inland oceans like the Aral Sea.

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European Space Agency Releases First High-Res Land Cover Map of Africa
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Land Cover CCI, ESA

This isn’t just any image of Africa. It represents the first of its kind: a high-resolution map of the different types of land cover that are found on the continent, released by The European Space Agency, as Travel + Leisure reports.

Land cover maps depict the different physical materials that cover the Earth, whether that material is vegetation, wetlands, concrete, or sand. They can be used to track the growth of cities, assess flooding, keep tabs on environmental issues like deforestation or desertification, and more.

The newly released land cover map of Africa shows the continent at an extremely detailed resolution. Each pixel represents just 65.6 feet (20 meters) on the ground. It’s designed to help researchers model the extent of climate change across Africa, study biodiversity and natural resources, and see how land use is changing, among other applications.

Developed as part of the Climate Change Initiative (CCI) Land Cover project, the space agency gathered a full year’s worth of data from its Sentinel-2A satellite to create the map. In total, the image is made from 90 terabytes of data—180,000 images—taken between December 2015 and December 2016.

The map is so large and detailed that the space agency created its own online viewer for it. You can dive further into the image here.

And keep watch: A better map might be close at hand. In March, the ESA launched the Sentinal-2B satellite, which it says will make a global map at a 32.8 feet-per-pixel (10 meters) resolution possible.

[h/t Travel + Leisure]

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Scientists May Have Found the Real Cause of Dyslexia—And a Way to Treat It
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iStock

Dyslexia is often described as trying to read letters as they jump around the page. Because of its connections to reading difficulties and trouble in school, the condition is often blamed on the brain. But according to a new study published in Proceedings of the Royal Society B, the so-called learning disability may actually start in the eyes.

As The Guardian reports, a team of French scientists say they've discovered a key physiological difference between the eyes of those with dyslexia and those without it. Our eyes have tiny light-receptor cells called rods and cones. The center of a region called the fovea is dominated by cones, which are also responsible for color perception.

Just as most of us have a dominant hand, most have a dominant eye too, which has more neural connections to the brain. The study of 60 people, divided evenly between those with dyslexia and those without, found that in the eyes of non-dyslexic people, the arrangement of the cones is asymmetrical: The dominant eye has a round, cone-free hole, while the other eye has an unevenly shaped hole. However, in people with dyslexia, both eyes have the same round hole. So when they're looking at something in front of them, such as a page in a book, their eyes perceive exact mirror images, which end up fighting for visual domination in the brain. This could explain why it's sometimes impossible for a dyslexic person to distinguish a "b" from a "d" or an "E" from a "3".

These results challenge previous research that connects dyslexia to cognitive abilities. In a study published earlier this year, people with the condition were found to have a harder time remembering musical notes, faces, and spoken words. In light of the new findings, it's unclear whether this is at the root of dyslexia or if growing up with vision-related reading difficulties affects brain plasticity.

If dyslexia does come down to some misarranged light-receptors in the eye, diagnosing the disorder could be as simple as giving an eye exam. The explanation could also make it easy to treat without invasive surgery. In the study, the authors describe using an LED lamp that blinks faster than the human eye can perceive to "cancel out" one of the mirror images perceived by dyslexic readers, leaving only one true image. The volunteers who read with it called it a "magic lamp." The researchers hope to further experiment with it to see see if it's a viable treatment option for the millions of people living with dyslexia.

[h/t The Guardian]

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