at risk

A Global Assessment Of Groundwater Wells | Earth Wise

May 19, 2021 By EarthWise Leave a Comment

Water is a fundamental need for every human being on the planet. Each person requires more than five gallons of clean and safe water a day for drinking, cooking, and keeping clean.

Groundwater wells remain one of the primary sources of drinking water. In fact, more than half of the world’s population gets its drinking water from groundwater wells. Groundwater wells also sustain more than 40% of irrigated agriculture.

Researchers from UC Santa Barbara have recently compiled the most comprehensive assessment of groundwater wells to date. Their research, which was recently published in the journal Science, spanned 40 countries, which collectively account for more than 50% of all groundwater pumping.

According to the survey’s findings, many wells are at risk of running dry – up to one in five wells, to be exact. The researchers compared the depths of water tables against well depths. They found that 6% to 20% of the wells in the study were at risk of running dry if water levels continue to decline by just a few meters.

In many areas where groundwater levels are declining, the research team found that new wells are not being drilled deeper to keep pace with the falling water table. As a result, newer wells are just as vulnerable as older wells should groundwater levels continue to decline.

The researchers hope to expand on this study to include data from China, Iran, and Pakistan, three major users of groundwater from which the researchers could not obtain records. The researchers also plan to investigate how quickly water tables are dropping and where the trend is accelerating.

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The largest assessment of global groundwater wells finds many are at risk of drying up

Photo, posted January 20, 2018, courtesy of François Molle via Water Alternatives Photos on Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sharks On The Decline | Earth Wise

September 4, 2020 By EarthWise Leave a Comment

During the past 70 years, global shark populations have been on the decline. Many species have become threatened or endangered. Conservation efforts have been underway in many places, but shark populations continue to be at risk because of over-fishing and habitat loss.

A comprehensive study by marine biologists at Texas A&M University deployed more than 15,000 baited remote underwater video stations on 371 coral reefs in 58 countries. The study included 59 different shark species in the Atlantic, Pacific and Indian Oceans. The researchers were surprised to find that no sharks at all were detected in almost 20% of the locations surveyed and were almost completely absent from coral reefs in several nations.

Scientists believe that demand for shark products, such as fins and meat, and bycatch (that is, sharks captured in nets by fisherman trapping other kinds of fish) are strong contributors to the widespread declines in shark numbers around the world.

The study shows that if corrective steps are not taken in regions where marine management is still ineffective, continued depletion of shark populations is highly likely.

Sharks have important roles in marine ecosystems. When their habitats deteriorate and their populations decrease, ecosystem stability and health is degraded because sharks help regulate prey populations.

Some countries, notably the Bahamas, are combating the problem by providing sanctuaries for sharks where fishing and harvesting is prohibited. Such places support some of the healthiest shark populations in the world. However, the decline of coral reefs is just another challenge facing shark populations around the world.

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Study Shows Alarming Decline In Shark Numbers Around The World

Photo, posted January 9, 2017, courtesy of Kris-Mikael Krister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas Will Erase Cities

December 18, 2019 By EarthWise Leave a Comment

According to new research, climate-driven sea level rise could affect three times more people by 2050 than previously thought. This sobering assessment means some of the world’s great coastal cities, including Bangkok, Shanghai, Mumbai, Basra, Alexandria, and Ho Chi Minh City, could be in big trouble.

Scientists have always relied on land elevation data to determine the effects of sea level rise over large areas. But standard elevation measurements using satellites struggle to differentiate the true ground level from the tops of trees or buildings. The authors of the paper developed a more accurate way to calculate land elevation by using artificial intelligence to determine the error rate and to correct for it. The new findings revealed that 150 million people – three times more than previously thought – are now living on land that is projected to be below the high-tide line by the middle of this century.

Eight Asian nations – China, Bangladesh, India, Vietnam, Indonesia, Thailand, the Philippines, and Japan – account for about 70% of the people living on at-risk land.

More than 20 million people in Vietnam, including much of Ho Chi Minh City, live on land that will be inundated by 2050. In Thailand, more than 10% of its citizens, including much of Bangkok, currently live on land imperiled by projected sea level rise.

This new research was produced by Climate Central, a New Jersey-based science organization, and was recently published in the journal Nature Communications.

Sea level rise is clearly not just an environmental problem. It’s a humanitarian crisis.

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New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding

Rising Seas Will Erase More Cities by 2050, New Research Shows

Photo, posted December 18, 2009, courtesy of Misko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Banning The Shark Fin Trade

July 4, 2019 By EarthWise Leave a Comment

Shark fins are considered a delicacy in many parts of the world, especially in China. Shark fin soup, for example, is often served at engagement parties and weddings. But the use of shark fins has come under increasing scrutiny in recent years, especially since an estimated one-third of fins are harvested from species deemed at risk.

Many of the fins used in shark fin soup come from a practice known as “finning,” which is an inhumane and wasteful practice where the fins are hacked from live sharks and then the sharks are thrown back into the water and left to die. According to U.N. estimates, 73 million sharks are killed every year for their fins.

The possession, sale, and distribution of shark fins is banned in 12 U.S. states, as well as in all European Union member states.

In 1994, Canada banned the practice of finning in its own waters, but allowed the import of fins to continue. Canada has been one of the largest markets for shark fins outside Asia, importing nearly 300,000 pounds of shark fins last year. But in late June, Canada passed a bill that bans both the import and export of shark fins harvested by shark finning. They are the first G7 and the first G20 country to do so.

But shark fins taken from sharks sustainably harvested for their meat will continue to be allowed in Canada. While demand for shark fins is decreasing globally, demand for shark meat is rising.

Since sharks still face a myriad of environmental pressures, including illegal fishing and high bycatch rates, there are concerns that this Canadian ban oversimplifies the threats facing global shark populations.

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Canada becomes the first G20 country to ban shark fin trade

Photo, posted January 4, 2013, courtesy of Andrew Currie via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.