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Great Salt Lake In Danger | Earth Wise

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Utah’s Great Salt Lake has been plagued by excessive water use and extensive drought conditions.  As of January, the lake dropped to record-low water levels, losing 73% of its water and exposing 60% of its lakebed. According to scientists, the lake could disappear entirely within five years.

Great Salt Lake is what is known as a “terminal lake,” which means that it is fed only by rain, snow, and runoff and has no rivers that take water to the ocean.  As a result, salt and minerals build up over time.  With so much salt in the water, only brine flies and shrimp can survive in it.  The unique ecosystem supports 10 million migratory birds.  As the lake continues to dry up, the water is becoming too salty for even algae and microbes to survive.  With shallow mud replacing previous shallow water, the nests of the 80,000 white pelicans that annually come to the lake are endangered by predators that can simply walk over to the eggs.

The historic low water levels have exposed 800 square miles of lakebed.  This lakebed holds centuries of natural and manmade toxins like mercury, arsenic, and selenium.  The exposed mud ultimately turns to dust that is carried off into the air.  This is contributing to what is already some of the worst winter air pollution in the nation.  Scientists warn that the unfolding ecological disaster may become a human health disaster.

State officials and university researchers have formed a “Great Salt Lake Strike Team” looking for ways to get more water to the lake.  There are a number of so-called moonshot proposals to save the lake.  It remains to be seen what will be done, but the clock is ticking.

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Great Salt Lake will disappear in 5 years without massive ‘emergency rescue,’ scientists say

Scientists fear a Great Toxic Dustbowl could soon emerge from the Great Salt Lake

Photo, posted September 19, 2009, courtesy of John Morgan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Great Salt Lake Is Disappearing | Earth Wise

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Utah’s Great Salt Lake is the largest saltwater lake in the western hemisphere.  According to data from the US Geological Survey, the surface water elevation of the Great Salt Lake has fallen to the lowest level since records began in the mid-1800s.  The average elevation is now 4,190 feet above sea level.   With this drop in water level, the surface area of the lake is little more than half of its historical size.  The lower water level has exposed about 700 square miles of previously submerged lakebed.

The lake now contains about a quarter of the volume of water that it did at its high point in 1987.  The precipitous drop in water is a result of water usage from the lake coupled with climate change-fueled drought.   Increased water demand is due to the rapidly growing population of metropolitan Salt Lake City.  Utah’s population is projected to increase by almost 50% by 2060.

The Great Salt Lake goes though seasonal cycles of water loss and replenishment.  Rain and snow generally refill its level.  However, because of the ongoing megadrought in the West, water evaporation and depletion continue to exceed the amount of water entering the lake.  The water levels are expected to further decrease until fall or early winter, when incoming water is expected to equal or exceed evaporation.

The decline of the Great Salt Lake is a serious threat to the economy, ecology, and people of northern Utah.  The lake generates snowpack, is a refuge for hundreds of migratory birds and other wildlife and generates millions of dollars in the economy through mineral extraction and tourism.

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Utah’s Great Salt Lake is disappearing

Photo, posted October 6, 2020, courtesy of Julie Girard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lake Tuz Is Disappearing | Earth Wise

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Lake Tuz is Turkey’s second-largest lake and one of the world’s largest hypersaline lakes.  Its high salt content makes it an ideal breeding ground for some migratory bird species, including flamingos, which are often present there in huge numbers in the spring and summer.

Now, Lake Tuz rarely spans an area much larger than a puddle. In some summers, it completely dries up.  It did so this past summer, which resulted in the deaths of thousands of flamingos.

According to experts, Lake Tuz is a victim of climate change-induced drought, which has hit the region hard, and decades of harmful agricultural policies that exhausted the underground water supply.

Water in this region has become increasingly scarce.  The Mediterranean Basin has already seen more frequent and intense droughts, and is considered a climate change hotspot. 

According to new research, which was recently published in the journal Regional Environmental Change, Lake Tuz generally contained enough water in August for the lake to be considered permanent up until 2000.  But between 2001 and 2016, something shifted.  Water spanned less than 20% of the lake in every August except for one, and droughts became more frequent and intense. And in some years, the lake completely dried up.   

What caused this change?  According to the research team, Lake Tuz’s decline coincided with the excessive use of groundwater and surface water resources responsible for feeding the lake.  Some streams were rerouted for agricultural purposes, while others were dammed.  And when surface water sources dwindled, people turned to groundwater that historically fed the springs in Lake Tuz. 

Lake Tuz may be on the brink of extinction. 

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Impact of climate variability on the surface of Lake Tuz (Turkey), 1985–2016

Disappearing Lake Tuz

Photo, posted August 16, 2021, courtesy of Godot via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Record Low For Lake Mead | Earth Wise

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Lake Mead is the reservoir that was formed by the Hoover Dam on the Colorado River.  The lake spans the Arizona-Nevada border.  It is the largest reservoir in the United States in terms of water capacity.  The lake is part of a system that supplies water to at least 40 million people in seven states and in Northern Mexico.

As of August 22, this year, Lake Mead was filled to just 35% of its capacity.  This low water level is happening while 95% of the land in nine Western states is under some level of drought conditions and 64% of the land is under extreme drought conditions.  A so-called megadrought has been going on for 22 years and may be the worst dry spell in the region in twelve centuries.

As of the end of July, the water elevation at the Hoover Dam was 1,067 feet above sea level, the lowest it has been since April 1937 when the lake was still being filled after dam construction.  The level has dropped by 132 feet since July 2000.  At maximum capacity, Lake Mead reaches an elevation of 1,220 feet and holds 9.3 trillion gallons of water.

With Lake Mead at 35% of capacity, Lake Powell on the Colorado at 31%, and the entire Lower Colorado system at 40%, water allocations for the coming water year are being cut back. Mexico will see a 5% reduction, Nevada will be cut 7%, and Arizona will lose 18% of its apportionment.   This unprecedented official declaration of a water shortage demonstrates the severity of the drought and low reservoir conditions.

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Lake Mead Drops to a Record Low

Photo, posted August 7, 2018, courtesy of Renee Grayson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Caspian Sea And Climate Change | Earth Wise

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According to the National Oceanic and Atmospheric Administration, global sea levels have been rising over the past century, and the rate has increased in recent decades.  Sea levels are currently rising about one-eighth of an inch every year.

Sea level rise is caused primarily by two factors related to climate change:  the added water from melting glaciers and ice sheets, and the expansion of seawater as it warms.  While climate change is causing global sea levels to rise, higher temperatures in other regions are having exactly the opposite effect.  The water levels are falling.

According to researchers from the University of Bremen in Germany, the Caspian Sea is a perfect example of how a body of water will change.  While it is named a sea due to its size and high salinity, the Caspian Sea is actually a lake.  In fact, it’s the largest lake in the world.  Its largest inflow is the Volga River and it has no natural connection to the ocean.  Its water level is determined by the proportional influences of inflow, precipitation, and evaporation.  Climate change is causing increased evaporation, which leads to a declining water level. 

According to the research team, the water level of the Caspian Sea could fall by 29 to 59 feet during this century.

The Caspian Sea is surrounded by Kazakhstan, Turkmenistan, Iran, Azerbaijan and Russia.  It’s an important regional water reservoir, and a biological and commercial center. 

The researchers hope the Caspian Sea will be used as an example in scientific research to assess the vulnerability of other regions to falling water levels.

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Climate crisis is causing lakes to shrink

Photo, posted October 31, 2016, courtesy of Amanderson2 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Road Salt Pollution

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Mirror Lake is a popular recreational lake located in the Village of Lake Placid.  It is the most developed lake within the Adirondack Park, which is a publicly protected area that is actually larger than Yellowstone, Yosemite, Glacier, and Grand Canyon National Parks combined.

New research has revealed that road salt runoff into Mirror Lake is preventing natural water turnover which poses a risk to the balance of its ecology.  The study, which was published in Lake and Reservoir Management, found that road salt runoff is preventing spring mixing of the water column.    This creates more anoxic water conditions, meaning there is less oxygen in the water, and limits the ability of the habitat to support the native lake trout. 

Mirror Lake is the first lake in the Adirondack Park to show an interruption in lake turnover due to road salt.  Many lakes in northern climes experience so-called “dimictic turnover”, which is a natural process where wind and less stratified water conditions of spring and fall allow mixing of the water column that redistribute oxygen and nutrients throughout the lake.  High levels of surface-water chloride introduced into the lake from road salt runoff inhibit the mixing of the water column.

The lack of mixing and oxygenation is bad news for fish species such as lake trout, which require cold, oxygenated water to survive.  It may also put the lake at a greater risk of algal blooms.

Mirror Lake is small, surrounded by concentrated development, and receives the direct discharge of stormwater.  So, it is particularly vulnerable to road salt contamination.  Other lakes elsewhere in New York may experience similar conditions.  The researchers are confident that natural turnover conditions could be restored to the lake if road salt application in the watershed is reduced.

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Road salt pollutes lake in one of the largest US protected areas, new study shows

Photo, posted January 5, 2018, courtesy of MTA of the State of NY via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lake George Health Report

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The Offshore Chemistry Program, run by the Darrin Fresh Water Institute at RPI, has been monitoring the deep waters of Lake George in New York for 40 years.  Lake George, nicknamed the Queen of American Lakes, is famed for the transparency of its water and a new report on the health of the lake reveals that it is doing rather well.

According to the report, although concentrations of chemicals and pollutants like salt and nutrients have increased in the deep waters of Lake George, they are still too low to harm the ecosystem at those depths.

The Offshore Chemistry Program studies the lake as part of a collaboration between RPI, IBM Research, and the FUND for Lake George that is called the Jefferson Project.  This long-term commitment provides a wealth of information over time matched by few lake studies in the world.

The recent results show that levels of salt, the nutrient orthophosphate, and chlorophyll have increased substantially over time, but none are yet at a level that will cause harm.

Orthophosphate occurs naturally, but most likely the higher levels are due to improperly functioning septic systems, failing wastewater treatment systems, and stormwater runoff.  The orthophosphate most likely triggered the increase in chlorophyll, which probably is associated with increased density of chlorophyll in individual algal cells, rather than an increase in total algal mass in the lake.

Overall, the results demonstrate the continuing resilience of Lake George to a growing array of stressors.  In nearly 40 years of human activities, the lake has changed in a number of ways, but the changes have so far been relatively small.  With such careful monitoring, we can hope to keep them that way.

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Four Decades of Data Sounds Early Warning on Lake George

Photo, posted September 24, 2009, courtesy of GPA Photo Archive via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saildrones For Science

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Nine years ago, engineer Richard Jenkins broke the world land speed record for a wind-powered vehicle with a sailboat on wheels driving across a dry lakebed at 126 miles per hour.  After years of engineering development, his technology has now taken on the form of a saildrone that can autonomously sail the sea gathering ecologic, oceanic and atmospheric data.

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Listening To Volcanoes

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Volcanoes are complicated, and we don’t have universally applicable ways to predict when they might erupt.  Measurements of seismicity, gas emissions and ground deformation are all useful in trying to figure out what volcanoes are up to.  However, it is unlikely that will ever have definitive prediction techniques.

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Learning From Fire

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The Tubbs Fire was the huge wildfire that burned parts of Napa, Sonoma and Lake counties in Northern California in October.  Between that fire and several smaller ones going on at the same time, at least 43 people died and over 8,400 homes and buildings were destroyed.  The Tubbs Fire alone burned over 36,000 acres. The even larger December wildfires in Southern California scorched hundreds of thousands of acres in multiple counties.

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DNA Analysis of River Water

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DNA analysis has become commonplace and inexpensive.  Millions of people have their DNA tested to learn about their origins and family connections.  And the technology has spread to biological research in the form of Environmental DNA or eDNA, which is such a powerful tool that it is transforming the field of wildlife biology.

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Saving Saharan Oases

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An oasis is an isolated area of vegetation in a desert, typically surrounding a spring or similar water source such as a pond or a small lake.  Oases can provide habitat for animals as well as people.   Oases have long been essential for trade and transportation routes in desert areas; caravans typically travel via oases so that supplies of water and food can be replenished.

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Bolivia’s Disappearing Lake

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Bolivia’s second largest lake has nearly disappeared. Lake Poopó, a saltwater lake located in a shallow depression in the Altiplano Mountains, used to cover an area about the size of Los Angeles. While it’s not the first time the lake has dried out, scientists believe its recovery hangs in the balance due to the combined stress of drought, climate change, and water diversion.

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