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Protecting Wetlands | Earth Wise

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Wetlands are distinct ecosystems that are flooded or saturated by water, either permanently or seasonally.  They include mangroves, marshes, swamps, forested wetlands, bogs, wet prairies, and vernal pools.   The feature that most wetlands share is soil or substrate that is at least periodically saturated with or covered by water.

Wetlands are some of the most threatened ecosystems in the world.  While wetlands can be affected by a variety of natural stressors, including erosion, droughts, and storms, human activities have been the major driver of wetland decline. 

But according to a new study by researchers from McGill University in Canada, the global loss of wetland areas since 1700 has likely been overestimated.  The research team calculated that the area of wetland ecosystems around the world has declined 21-35% since 1700 as a result of human activities – far less than the 50-87% decline estimated in other studies.  The study’s focus beyond regions with historically high wetland losses and its avoidance of possibly misleading extrapolations likely resulted in the lower estimate.      

According to the study, which was published in the journal Nature, more than 2.1 million square miles of wetlands have been lost during the past 300 years – an area roughly the size of India.  The five countries with the highest wetland losses are the United States, China, India, Russia and Indonesia. 

But discovering that fewer wetlands have been historically lost than previously thought gives researchers a second chance to protect wetlands.  The findings of the study will help researchers prioritize global conservation and restoration actions.

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A second chance to protect wetlands

Photo, posted February 2, 2005, courtesy of Jan Tik via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Storms And The Megadrought | Earth Wise

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California experienced its wettest 10-day period in 25 years as a result of a series of storms driven by atmospheric rivers in January.  The Rocky Mountains got buried in snow from the same weather pattern.   For the drought-stricken West, the storms were good news.  But they are not the cure for what’s been ailing the region.

In California, the snowpack in the Sierra Nevada mountains has been greatly enhanced, containing twice as much snow as is considered average for this time of year.  Without a doubt, it will reduce the impact of the drought that has plagued the state for 23 years.  But one big storm or even a series of them is not enough to undo years of minimal precipitation and rising temperatures.  Many of the states’ largest reservoirs remain well below historical averages despite the record-breaking rain.  It would take several wet years to really allow the state to recover from the drought.

The snowfall in the Rockies is crucial because it is the source of more than two-thirds of the water in the Colorado River.  The Colorado River is the water lifeline for 40 million people from Wyoming to Mexico.

The ongoing shrinking of the Colorado River is a crisis that has created massive problems for the multibillion-dollar agriculture industry and for many large cities, including Denver, Phoenix, Salt Lake City, Las Vegas, and Los Angeles.  Two of the nation’s largest reservoirs – Lake Mead and Lake Powell – are filled by the Colorado River.  The historic low levels of these reservoirs have threatened the functioning of hydropower facilities that provide electricity to millions of people.

The January storms were good news for the West, but its problems are not over.

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This Winter’s Rain and Snow Won’t be Enough to Pull the West Out of Drought

Photo, posted September 18, 2022, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Complicated Year For Energy | Earth Wise

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2022 was a complicated year for global energy.  Following its invasion of Ukraine, Russia curtailed natural gas exports to Europe.  This led to large increases in coal burning in many countries, but at the same time led to major new investments in renewable energy.  Projections are that the world will add as much renewable power in the next five years as it did over the previous 20.

In China, severe drought reduced the amount of available hydropower, which drove increased demand for coal in that country.  Between the war in Ukraine and the Chinese drought, coal burning reached an all-time high in 2022, albeit only a 1% uptick for the year.  This increased coal consumption is expected to be only temporary as the accelerating deployment of renewables, energy efficiency, and the use of heat pumps will inexorably reduce coal use.

Globally, governments have earmarked an additional $500 billion for clean energy just since March, bringing the total since the onset of the COVID pandemic to more than $1.2 trillion.  Nearly half of this total investment comes from the U.S. under the Inflation Reduction Act and the Infrastructure Investment and Jobs Act.

In light of these energy policies around the world, the International Energy Agency has revised its projections for renewable energy to substantially larger numbers.   Renewables are expected to surpass coal as the world’s largest source of electricity by early 2025. The global energy crisis triggered by the war in Ukraine has kicked off an extraordinary new phase of rapid renewables growth as countries around the world are seeking to obtain energy security as well as the other benefits of clean energy.

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In 2022, Energy Shocks Spurred Both Unprecedented Coal Burning and Massive Renewable Investments

Photo, posted April 5, 2015, courtesy of Jan Remund via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Harvesting Fresh Water From Ocean Air | Earth Wise

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Roughly three-quarters of the world population has access to a safely managed water source.  That means that one-in-four people do not have access to safe drinking water.  Even in the wealthy United States, persistent drought in the west is creating problems in places like Phoenix, Arizona.

Water is plentiful on Earth but more than 99% of it is unusable by humans and many other living things because it is saline, frozen, or inaccessible.  Only about 0.3% of our fresh water is found in the surface water of lakes, rivers, and swamps.

There is an almost limitless supply of fresh water in the form of water vapor above the oceans, but this source is untapped.  Researchers at the University of Illinois have been evaluating the feasibility of a hypothetical structure capable of capturing water vapor from above the ocean and condensing it into fresh water.

Existing ways to obtain fresh water like wastewater recycling, cloud seeding, and desalination have met only limited success and present various problems with regard to cost, environmental impact, and scalability.

The researchers have proposed hypothetical large offshore structures measuring 700 feet by 300 feet to capture water vapor that is continually evaporating from the ocean in subtropical regions.   Their modeling concluded that such structures could provide fresh water for large population centers in the subtropics.  Furthermore, climate projections show that the amount of water vapor over the oceans will only increase over time, providing even more fresh water supply.

This is only a theoretical study at this point, but the researchers believe it opens the door for novel infrastructure investments that could address global water scarcity.

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Researchers propose new structures to harvest untapped source of fresh water

Photo, posted June 28, 2009, courtesy of Nicolas Raymond via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trees Are Growing Bigger | Earth Wise

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The alarming rate of carbon dioxide flowing into the atmosphere is having a real and actually positive effect on plant life. Higher concentrations of carbon dioxide make plants more productive because photosynthesis makes use of the sun’s energy to synthesize sugar out of carbon dioxide and water.  Plants make use of the sugar both as a source of energy and as the basic building block for growth.  When carbon dioxide levels go up, plants can take it up faster, supercharging the rate of photosynthesis.

In a new study published in the journal Nature Communications, scientists at Ohio State University found that trees are feasting on decades of carbon dioxide emissions and are growing bigger as a result. 

The researchers tracked wood volume in 10 different tree groups from 1997 to 2017 and found that all of them except aspens and birches grew larger.  Over that time period, carbon dioxide levels climbed from 363 parts per million to 405 parts per million.  According to the study, each 1% increase in lifetime CO2 exposure for trees has led to more than a 1% increase in wood volume.

In the big picture, the news isn’t so positive.  The global warming caused by increasing carbon dioxide levels increasingly threatens the forests of the world.  It has led to worsening droughts, insect infestations, and wildfires.  So overall, increasing levels of carbon dioxide are by no means a good thing for the world’s trees.  However, since trees are growing bigger more quickly, it means that planting them is an increasingly cost-effective method for fighting climate change because the same number of trees can sequester more carbon.

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As Carbon Dioxide Grows More Abundant, Trees Are Growing Bigger, Study Finds

Photo, posted September 12, 2015, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Bad Year For California Rice | Earth Wise

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Rice production is the third largest cereal crop in the United States after corn and wheat.  Four regions in the country produce almost the entire U.S. rice crop:  the Arkansas Grand Prairie, the Mississippi Delta, the Gulf Coast, and the Sacramento Valley in California.  Arkansas is the largest producer of rice in the country by far, but California ranks second.

A combination of drought and water shortages in the Sacramento Valley has taken a major toll on the California rice crop.  This year, rice growers have only planted half as much grain as usual.  The changes in rice plantings in California are so substantial that they are easily visible from space.

In Colusa and Glenn counties, rice acreage this year dropped by 84 and 75 percent respectively, compared to 2021.  Farther to the east, in Butte Country, rice acreage was down by 17%.  The change was smaller there because farmers in that county had more groundwater to tap into.

According to the USDA, the California rice crop will be reduced by 38% this year, making it the smallest rice crop in the state since 1977.  California mostly grows short- and medium-grained rice, which is used in dishes like sushi, paella, and risotto.  Arkansas and other states produce most of the long-grain rice such as basmati and jasmine rice.

In late September, there was a burst of rain, which offered some short-term relief for farmers.  However, it will take much more wet weather to ease the ongoing drought conditions.  As of the end of September, over 40% of California remained in extreme drought and 17% was in exceptional drought.

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A Rough Year for Rice in California

Photo, posted March 21, 2020, courtesy of Ajay Suresh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects In A Changing Climate | Earth Wise

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Insects can be found in every environment on Earth and are critical components of many ecosystems.  They perform countless important functions, including aerating and fertilizing soil as well as pollinating flowers.  In fact, according to the USDA, 75% of the world’s flowering plants and about 35% of the world’s food crops depend on animal pollinators, the majority of which are insects, to reproduce.

According to a study published in the journal Nature earlier this year, the combination of climate change and intensive agriculture is having a profound impact on both the abundance and diversity of insects.  In regions where substantial warming had occurred and where land had been converted for intensive farming, insects were nearly 50% less abundant and more than 25% fewer species were observed.  Tropical regions were among those most at risk for heavy losses.

According to a new study recently published in the journal Global Change Biology, tropical insects will be even more susceptible to climate change than previously thought.  In a five-year study conducted in Peru, researchers from the Florida Museum of Natural History found that insect populations declined 50% following short periods of drought and following short periods of heavy rainfall.  Insect populations decreased after three months of dry weather, but also decreased after three months of exceptionally wet weather.   

Researchers have known that tropical insects don’t tend to do well when their habitats dry out.  But the researchers were surprised to discover that these insects were equally averse to increased precipitation.  Alarmingly, precipitation is expected to become more frequent and more intense as a consequence of the changing climate. 

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Tropical insects are extremely sensitive to changing climates

Photo, posted June 11, 2016, courtesy of Z. Leng via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Beavers As Climate Change Fighters | Earth Wise

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California is fighting the effects of climate change on multiple fronts.  The state has been grappling with relentless drought, record heat waves, and persistent wildfires.  The California Department of Fish and Wildlife is enlisting the help of beavers in its battle against climate change.

The state has created a beaver restoration unit charged with developing methods for nature-based restoration solutions involving beavers as well as artificial beaver dams. The agency plans to spend at least $3 million over the next two years to oversee a restoration program for the North American beaver.

A 2020 study showed that beaver-dammed corridors were relatively unharmed by wildfires compared with other areas that lacked beaver damming.  The study highlighted the differences between two adjacent corridors – one without a beaver population with a landscape scarred by a recent wildfire and another with beavers that remained a lush wetland after a fire.   The differences in burn severity, air temperature, humidity, and soil moisture between the beaver complex and the adjacent landscape were huge. 

From the 1920s through the 1950s, California actively exported beavers to other parts of the state and country so they could build dams in eroded areas where beaver dams could help evenly distribute water.  Now, the state wants to reintroduce beavers into watersheds where they once flourished.

The Department of Fish and Wildlife’s proposal to the California Legislature called beavers an important keystone species that can be used to combat climate change.   The state has spent enormous amounts of money on wildfire measures with minimal results.  Now they are going to see if beavers can make a difference.

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California says the beaver can be superhero in fighting climate change

Photo, posted September 19, 2021, courtesy of Larry Lamsa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

History Emerges In European Drought | Earth Wise

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During the summer, much of Europe faced a string of extreme heat waves and a devastating drought.  As a result, many reservoirs and rivers have shrunk back to reveal historical structures and relics that, in some cases, date back thousands of years.  Once-submerged villages, ships, and bridges have re-emerged this year.

In northwest Spain, a former village called Aceredo has reappeared after having been submerged 30 years ago when a hydropower dam flooded the valley where it was located.  Elsewhere in Spain, the Dolmen of Guadalperal, a 4000-5000-year-old stone monument often called the Spanish Stonehedge, has risen from a drought-stricken dam west of Madrid

In Italy, which is suffering from its worst drought in 70 years, the ruins of a bridge from the time of Nero are now visible in the Tiber River.   One of Germany’s largest reservoirs, the Edersee, has shrunk back so much that parts of Berich, a village that was flooded in 1914, can be seen.  In Serbia, water levels in the Danube River are so low that more than a dozen sunken Nazi boats from World War II have been exposed in the town of Prahovo.   In Northern England, the lower water levels of the Batings Reservoir have uncovered an ancient packhorse bridge.

The shrinking of riverbeds and reservoirs across Europe has attracted a great deal of attention, probably more than many other effects of the increasing number of extreme weather events because it is so visual.  But the frequency of extreme heat and drought is only likely to increase over time.

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Europe’s Shrinking Waterways Reveal Treasures, and Experts Are Worried

Photo, posted July 13, 2017, courtesy of Marco Brandstetter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving Giant Sequoias | Earth Wise

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Last year, the KNP Complex Fire burning in Sequoia National Park drew global attention as the General Sherman, the world’s largest tree, was wrapped in tinfoil-like material in order to repel the flames from the fire.  Hundreds of firefighters labored for weeks trying to save giant redwood trees.  Despite these efforts, the U.S. Forest Service estimates that wildfires killed 13% to 19% of the world’s giant sequoias in 2020 and 2021.

This past July, the Washburn Fire burned through part of Yosemite’s Mariposa Grove and the giant sequoias there were surrounded by automated sprinklers trying to shelter them from the flames.

For a century, government agencies have worked to extinguish all natural wildfires and prohibited Native people in the region from lighting the fires they traditionally used to manage their lands.  As a result, forests have grown far thicker with trees that can fuel fires.  The Sierras are now home to more than three times as many trees as when they were managed by indigenous communities.  But more than 100 million of those trees had died by 2016 because of drought.

Add to this massive amount of kindling the effects of climate change – a hotter and drier environment – and there is the perfect storm for megafires among the giant sequoias.

There is federal legislation pending that would provide resources for prescribed burning and other forms of active forest management.  It is controversial.  It has attracted support from the Nature Conservancy, the Save The Redwoods League, and others, but also opposition from more than 80 environmental groups.

What is not controversial is that the Giant Sequoias are in the midst of a crisis and urgent action is needed.

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In California, a Race to Save the World’s Largest Trees From Megafires

Photo, posted December 10, 2014, courtesy of Laura Camp via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Coping With Climate Change | Earth Wise

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Extreme weather events including prolonged drought and heavy rainfall are becoming more common and more severe as global temperatures rise.  As the climate continues to change in the coming decades, how will animals respond? 

Researchers from the University of Southern Denmark have examined how different mammals react to climate change. They analyzed data on population fluctuations from 157 mammal species around the world.  They compared these fluctuations with weather and climate data from the same time period.  The research team had 10 or more years of data for each species studied. 

The researchers found that mammals that live for a long time and/or produce less offspring –  like llamas, elephants, bears, and bison – are more climate resilient than small mammals with short lives — like mice, possums, lemmings, and rare marsupials. 

For example, large, long-lived mammals can invest their energy into one offspring, or simply wait for better times if conditions become challenging.  On the other hand, small, short-lived mammals like rodents have more extreme population changes in the short term. In the event of a prolonged drought, large portions of their food base may rapidly disappear, and they are left to starve because they have limited fat reserves.

However, the research team notes that the ability of a species to withstand climate change must not be the only factor when assessing a species’ vulnerability.  In fact, in many cases, habitat destruction, poaching, pollution, and invasive species pose a larger threat to animal species than climate change. 

While the study only examined 157 species, the findings enable researchers to also predict how animals they know less about will react to climate change.

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Which animals can best withstand climate change?

Photo, posted July 8, 2018, courtesy of Ray via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Climate Legislation | Earth Wise

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At the end of its summer session, California’s state legislature passed five climate-related bills including ones that it had been unable to pass in previous sessions.  Taking all of these actions puts California in the position of blazing a trail for the country and the rest of world in taking aggressive action on climate issues.

One bill confirmed California’s goal of reaching net-zero emissions by 2045.  Another bill added interim-term targets to go along with the state’s goal of 100% renewable electricity by 2045.  It sets a target of 90% by 2030 and 95% by 2040.  That bill mandates that California state agencies use 100% clean energy by 2035, which is a decade earlier than the previous requirement.

A third bill requires the California Air Resources Board to determine steps and regulations for carbon-capture and storage projects at pollution hotspots like oil refineries.

A fourth bill requires the state to set goals for removing carbon dioxide from the atmosphere through natural means such as tree planting.

The California state budget includes a record-breaking $54 billion to be spent on climate programs over the next five years, including $6.1 billion toward electric vehicles, $14.8 billion towards public transit projects, more than $8 billion for electric grid stabilization, $2.7 billion towards preventing wildfires, and $2.8 billion towards managing drought.

California has been dealing with ongoing drought and numerous wildfires and is highly motivated to take decisive action in dealing with the climate crisis.  California’s environmental initiatives often result in comparable actions taken by other states.

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California Passes Massive Climate Legislation Package

Photo, posted March 16, 2019, courtesy of Raymond Shobe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Food For The Future | Earth Wise

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Researchers predict that climate change will negatively impact most staple food crops, including rice, corn, and soybeans.  Therefore, climate resilient food crops – those that are salt, drought, and heat resilient – will have an important role to play in global food security.  Examples of climate resilient crops include quinoa, kernza, amaranth, millet, and tepary beans.    

According to a new study by researchers from Northwestern University, breadfruit – a starchy tree fruit native to the Pacific Islands – will be relatively unaffected by climate change.  Because breadfruit is climate resilient and well-suited to grow in regions with high levels of food insecurity, the research team suggests breadfruit could be a part of the solution to global hunger.

While it has ”fruit” in its name, breadfruit is more like a potato.  It’s starchy and seedless, and is closely related to jackfruit.  Breadfruit is nutrient-rich, and high in fiber, vitamins, and minerals.  It can be steamed, roasted, fried, fermented, and even turned into flour.  People in tropical regions around the world have been eating breadfruit for thousands of years. 

In the study, which was recently published in the journal PLOS Climate, researchers determined the climate conditions necessary to cultivate breadfruit and then looked at how these conditions are predicted to change in the future.  They examined two future climate scenarios: one that reflects high greenhouse-gas emissions and another in which emissions stabilize.

In both scenarios, the regions suitable for breadfruit cultivation were mostly unaffected.  Additionally, the researchers identified new suitable land where breadfruit cultivation could expand.   

As the climate continues to change, breadfruit might soon be on a table near you.

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Climate-resilient breadfruit might be the food of the future

Photo, posted August 11, 2007, courtesy of Malcolm Manners via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rewilding The American West | Earth Wise

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Oregon State University scientists have proposed a series of management changes for western federal lands aimed at re-establishing ecosystems there.  Their proposal would result in more gray wolves and beavers in nearly 200,000 square miles of federal lands in 11 states.

In each of those states, the researchers identified areas containing prime wolf habitat.  Gray wolves were hunted to near extinction in the West but have been gradually reintroduced in some areas starting in the 1990s.  Wolf restoration offers significant ecological benefits by helping to naturally control the population of grazing animals such as elk.  This in turn facilitates the regrowth of vegetation species such as aspen, which ultimately supports diverse plant and animal communities.

Beaver populations, which used to be robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many areas.  By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and settlement retention, maintain water flows during droughts, and increase carbon sequestration.

According to the researchers, the biggest threat to these western lands is livestock grazing, which has degraded ecosystems to a great extent.  They recommend the removal of grazing on about 30% of the federal lands being used for that purpose and instead would have rewilding efforts go on. 

The American West is going through a period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires, and loss of biodiversity.  Rewilding is a way to reestablish long-standing ecosystems.

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More wolves, beavers needed as part of improving western United States habitats, scientists say

Photo, posted October 1, 2020, courtesy of Tina DaPuglet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tepary Beans | Earth Wise

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Tepary beans are an ancient crop native to the northern part of Mexico and the southwestern part of the U.S..  They have been grown in those places by native peoples since pre-Columbian times.  They are still grown in Native American reservations in Arizona’s Sonoran Desert.  One can purchase them from some small farms in that region. 

What sets tepary beans apart from other beans is that they are among the most drought- and heat-tolerant legume crops in the world.  They can be grown without irrigation under conditions that are not viable for other crops.  They can be consumed by people like many other kinds of beans, and they can also provide forage for livestock with better nutrition content than many other plants.  They seem to be a very attractive option for a crop in the changing climate.  What is lacking, at present, is large supplies of tepary seeds to be planted.

Researchers at Texas A&M have been funded to bring tepary beans into modern cropping systems and diets.  The goal is to develop tepary bean cultivars with high biomass and yield that are still well-suited to drought and heat conditions.  Getting the beans to the point of widespread commercialization will take several years.  The end result should be of interest to pulse growers, seed industries, and food companies across the U.S.

Tepary beans are higher in fiber and protein than most other beans.  They come in several different colors, each of which has unique flavor and texture characteristics.  The white ones have a naturally sweet flavor.   The brown beans are slightly nutty in flavor and are similar to pinto beans.  If the Texas program is successful, we may all be eating tepary beans some day.

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Tepary Beans Offer Producers A Low-Input, Climate-Resilient Legume Alternative

Photo, posted August 25, 2017, courtesy of Katja Schulz 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.

California Trees Are Dying | Earth Wise

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California relies on extensive forests to help reduce the amount of carbon dioxide entering the atmosphere.  But extensive drought and increasingly frequent wildfires have been reducing the state’s tree population for the past three decades.

A comprehensive study by a team of scientists from the University of California Irvine used satellite data to study vegetation changes between 1985 and 2021.  Across the entire state, tree cover area has declined 6.7% over that time period.  The results varied from region to region across the state.

Southern California exhibited the sharpest decline, where 14% of the tree population in local mountain ranges vanished, potentially permanently.  In the Sierra Nevada mountains, tree populations were relatively stable until about 2010.  After that, a severe drought followed by historically large wildfires resulted in a 8.8% die-off of trees.  The northern parts of the state, with higher rainfall and cooler temperatures, fared better, being able to more easily recover from wildfires.

The study goes beyond measuring the tree population of the state and its effects on carbon storage.  The data is also important for understanding how changes in forest cover affects water resources and fire behavior in the state.

The decline of trees in California is affecting the carbon storage abilities of the state.  The satellite survey showed that as the tree populations have dropped, the state’s coverage of shrubs and grasses has risen, possibly indicating that permanent ecosystem shifts are occurring.  The forces contributing to the decline of trees in California are not going away any time soon.  As a result, the threat to California’s ability to mitigate the effects of climate change continues to grow.

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UCI study: California’s trees are dying, and might not be coming back

Photo, posted March 24, 2016, courtesy of David Fulmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Cotton More Sustainable | Earth Wise

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In the United States, cotton is a $7 billion annual crop grown in 17 states.  Cotton plants in the largest producing countries in the world – India, China, and the U.S. – are genetically very similar and, like other crops that lack diversity, can be at risk.

Cultivated cotton around the world has been bred to look and act very similar.  It is high yielding and easy to harvest using machines.  But it is also wildly unprepared to fight disease, drought, or insect-borne pathogens.

Researchers are looking beyond breeding for ways to combat the low genetic diversity of cultivated cotton.  There are new approaches that combine breeding with elements of genetic modification.  Most cotton in the U.S. has already been genetically modified to resist caterpillar pests.  But as new problems emerge, new solutions will be needed that may require complicated changes to the cotton genome.  Getting regulatory approval for a genetically modified crop is a long and expensive process.

However, ordinary genetic modification is not the only possibility.  Modern genetic sequencing technology can allow researchers to examine various wild cotton varieties and identify the genetic markers for desirable traits.  Once valuable genes in wild species have been identified, traditional plant breeding techniques could be used to produce cultivated cotton varieties that are more resistant to disease and drought.

Climate change is raising average global temperatures and some important cotton-producing regions such as the U.S. Southwest are becoming drier.  Researchers are hoping to produce cultivated cotton that can tolerate drought at the seedling stage.  The ultimate goal is to create more sustainable and genetically diverse cotton that can thrive in a changing world.

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Cotton Breeders Are Using Genetic Insights To Make This Global Crop More Sustainable

Photo, posted November 9, 2008, courtesy of BP Takoma via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Forests And Water | Earth Wise

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We hear a great deal about the environmental services provided by forests.  Deforestation is one of the major factors contributing to increasing levels of carbon dioxide in the atmosphere.  And, of course, forests – most notably rainforests – are major contributors to biodiversity.  A new study by the U.S. Forest Service looked at the role forests play in providing water for Americans.

According to the study, published in the journal Water Resources Research, forested lands across the U.S. provide 83 million Americans with at least half of their water.  125 million people – well over a third of the country – receive at least 10% of their water from forests.  Notably, in the drought-stricken western U.S., nearly 40 million people get more than half of their drinking water from forests that are increasingly threatened by wildfires.

The study looked at surface water sources for more than 5,000 public water systems.  It provides a critical update to the map of where our water comes from.  The study focused on surface waters such as lakes, rivers, and streams because it is too difficult to trace sources of groundwater on a national scale.  Included is a new database of inter-basin water transfers, which are how surface water moves from places where it is plentiful to where it is not.  Examples are the California Aqueduct and the Central Arizona Project which respectively supply Los Angeles and Phoenix with drinking water.  

In Los Angeles, 69% of the water coming in through inter-basin transfers originated in forested lands.  In Phoenix, the figure is 82%.  There are many urban communities that obtain more than half of their drinking water from inter-basin transfers.  Even far from forests, water from forests is essential for millions of Americans.

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U.S. Forests Provide 83 Million People with Half Their Water

Photo, posted September 26, 2016, courtesy of Don Graham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Solar | Earth Wise

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The largest floating solar array in Europe, 12,000 panels sitting on top of the Alqueva Reservoir in Portugal – will come online in July.  Installing floating solar arrays, which are sometimes called “floatovoltaics”, produce renewable energy while shielding significant expanses of water from the sun’s heat.  These dual benefits have led to floatovoltaic projects in multiple countries around the world.

The city of Cohoes, in New York’s Albany County, has proposed an 8,000-panel floating solar array on the city reservoir.  Federal funding of $3 million for the project was obtained by local Congressman Paul Tonko and, in May, utility National Grid donated $750,000 towards the project.  Engineering work will shortly be underway on the 3.2 megawatt grid of solar panels.

The city of Cohoes pumps its drinking water supplies from the Mohawk River into the 10-acre, manmade reservoir.  The surface of the water is the largest undeveloped open space in the city.  Such reservoirs constitute prime sites for solar arrays since the space cannot be used for other purposes.  In addition, covering the water’s surface with the solar panels greatly reduces evaporation and helps to inhibit the growth of algae.

There are currently only 14 floating solar arrays in the U.S. and all of those are privately owned.  The Cohoes municipal array will be the first of its kind.  There are nearly 500 reservoirs in New York State and 24,000 nationwide that could be sites for floating arrays.   Drought-stricken Western reservoirs like Lake Mead and Lake Powell could be ideal locations of solar arrays.  Those reservoirs lose huge amounts of water to evaporation.  There are estimates that floating arrays could provide as much as 10% of the nation’s electrical needs.

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Web Links

National Grid gives Cohoes $750,000 for floating solar array project

Photo, posted August 25, 2010, courtesy of Martin Abegglen via Flickr.

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