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

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

Earth Wise is a production of WAMC Northeast Public Radio.

Record Renewable Use In California | Earth Wise

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California, the most populous state, is the second largest electricity user.  Only Texas, the second most populous state, uses more energy, in part because it consumes large amounts in refining fossil fuels. Overall, California uses about 8% of the electricity generated in the U.S.

Thus, it was a significant milestone when briefly, on April 3, a record 97.6% of the energy on California’s statewide grid came from renewable energy resources.  (The previous record of 96.4% was set just a few days earlier).

Renewable energy’s share of the power typically peaks in the spring when mild temperatures keep demand relatively low and higher sun angles drive greater solar energy production.

On April 8, a record peak solar power production was set at 13,628 megawatts just after noon.  On March 4, the state set an all-time wind generation record of 6,265 megawatts. 

California now has over 15,000 MW of grid-connected solar power and 8,000 MW of wind.  Another 600 MW of solar and 200 MW of wind are coming online by June.  The state also has about 2,700 MW of energy storage online and that will climb to 4,000 MW by June.

In 2020, 34.5% of the state’s retail electricity sales came from wind and solar sources.  Adding in hydropower and nuclear power, nearly 60% of the state’s electricity came from non-fossil fuel.  Despite the effects of drought on hydropower generation and the impact of the pandemic on the pace of renewable energy projects, California continues its dramatic transition to sustainable energy.

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Solar and wind notched records as renewables met California’s energy demand

Photo, posted September 20, 2016, courtesy of Tom Brewster Photography / BLM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Atmosphere Is Thirstier | Earth Wise      

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The American West is in the throes of a two-decade-long drought.  The climate there is getting warmer and drier, which has led to increasing demand for water resources from both humans and ecosystems.  According to a new study by the Desert Research Institute and collaborators, the atmosphere across much of the U.S. is also demanding a greater share of water than it used to.

Evaporative demand, which is also called atmospheric thirst, is a measure of the potential loss of water from the earth’s surface up to the atmosphere.  It is a function of temperature, humidity, wind speed, and solar radiation.  The study, published in the Journal of Hydrometeorology, assessed trends in evaporative demand during a 40-year period from 1980-2020.

The study’s findings showed substantial increases in atmospheric thirst across much of the Western U.S. over that period, with the largest increases centered around the Rio Grande and Lower Colorado rivers.  This is important because atmospheric thirst is a persistent force in pushing Western landscapes and water supplies toward drought.

The study found that, on average, increases in temperature were responsible for 57% of the changes observed in atmospheric thirst, humidity 26%, and the other factors playing lesser roles.

For farmers and other water users, increases in atmospheric thirst mean that, in the future, more water will be required to meet existing water needs.  Crops already require more water than they did in the past and can be expected to require more water in the future.  Over time, for every drop of precipitation that falls, less and less water is likely to drain into streams, wetlands, aquifers, or other water bodies.

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New study shows robust increases in atmospheric thirst across much of U.S. during past 40 years

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cloud Seeding And The Western Drought | Earth Wise

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The massive megadrought affecting the American West is now considered to be the driest two-decade period in the past 1,200 years.  The lengthy drought has led to increased wildfires, reduced agricultural productivity, and reduced electricity generation by hydropower plants.  The historically low water levels in the largest two reservoirs in the U.S. – Lake Mead and Lake Powell – has triggered reductions in water allocations to Arizona, Nevada, and Mexico.

Several western states have expanded cloud seeding programs in an attempt to increase precipitation.  During the past two years, Idaho, Utah, Colorado, Wyoming, and California have all stepped up their cloud seeding efforts.  Outside of the US, the United Arab Emirates and China both have implemented massive cloud seeding programs.

A study by researchers at the University of Colorado and the National Center for Atmospheric Research looked at the ability of cloud seeding to increase snowfall.  The study unambiguously demonstrated that cloud seeding can increase snowfall.  Just how effective it is in terms of how much additional snow seeding produces is less clear.

Given the dire need for water and the fact that cloud seeding is not especially expensive, governments and other users are not hesitating to make use of it.

Unfortunately, the study shed no light on the efficacy of warm weather seeding to produce rain.  There is in fact little evidence that seeding clouds to produce rain accomplishes very much.  Once again, the prevailing view is that it is worth trying.  There do not appear to be environmental downsides to seeding.

The hope is that cloud seeding may at least restore clouds to the state they had been in before industrial pollution and other human activities affected them.

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Can Cloud Seeding Help Quench the Thirst of the U.S. West?

Photo, posted November 21, 2013, courtesy of Sharon Tate Soberon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Historic Western Drought | Earth Wise

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The American Southwest has suffered from drought conditions since the year 2000.  The drought has reduced water supplies, devastated farmers and ranchers, and it has helped to fuel numerous wildfires across the region.  It has generally been considered to be worst in 500 years.

According to a recent analysis, the drought has become so severe that it has actually led to the driest two decades in at least 1,200 years and the changing climate is largely responsible.  The summer of 2021 was especially dry; about 2/3 of the West was in severe drought conditions.

Scientists at UCLA used tree ring data to gauge drought.  Based on that analysis, 2000-2021 is the driest 22-year period since 800 A.D. which is as far back as the data goes.

The study confirmed the role of temperature, more than precipitation, in driving exceptional droughts.  Precipitation levels can go up and down over time and can vary in different regions.  But the ongoing emissions of greenhouse gases into the atmosphere are causing temperatures to generally rise over time.  Warmer temperatures make the air more capable of pulling water out of the soil, out of vegetation, out of crops, and out of forests.  All of that makes drought conditions more severe.

A megadrought is generally considered to be one that is both severe and long.  But even during one, there can be wet years.  2005 was a notable one.  But there must be enough consecutive wet years to actually end a drought.

Several previous megadroughts over the past 1,200 years lasted as long as 30 years.  So, the current drought is in full swing and may go on for a long time to come.

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How Bad Is the Western Drought? Worst in 12 Centuries, Study Finds.

Photo, posted September 25, 2021, courtesy of David Sierralupe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Koalas Are Endangered | Earth Wise             

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The koala is one of the world’s most iconic animal species and is widely considered to be the symbol of Australia.   Koalas are not bears; they are marsupials. 

Being iconic symbols is not sufficient to prevent koalas from going extinct.  In the 1920s, hundreds of thousands of koalas were shot for the fur trade, greatly reducing their population.

More recently, drought, bush fires, disease, and habitat loss have drastically reduced the numbers of koalas.  Since 2018, there has been a 30% decline in koala populations across Australia.  It is difficult to get an accurate count of the animals because they don’t move around much, and they live high up in tree canopies where they are hard to spot.

 Estimates are that the koala population has dropped from between 45,000-82,000 in 2018 to between 32,000-58,000 in 2021.  The koala is now extinct in 47 Australian electorates and in many others, there are only handfuls of animals remaining.   The population decline was accelerated by devastating wildfires in late 2019 into early 2020.  Some estimates are that koalas could be extinct by 2050.  Conservation organizations around the world have been demanding greater protection for koalas for years.

Given this dire situation, the Australian government recently declared the koala an endangered species, reclassifying it from being a vulnerable species.  The government plans to adopt a recovery plan that will include new laws protecting koalas and their natural woodland environments.  The details of the plan remain to revealed.

According to the Australian Koala Foundation, however, the new status of the koala means very little in and of itself.  If the clearing of the koala habitat continues, the species has little chance of surviving in the wild.

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‘In rapid decline’: Australia has lost 30% of its koalas in just 3 years, foundation says

Australia Declares Koalas an Endangered Species

Photo, posted September 18, 2019, courtesy of Guido Konrad 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.

Bomb Cyclones | Earth Wise

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It seems like we are hearing about new weather phenomena pretty frequently these days.  One name that has popped up lately is “bomb cyclones.”  Bomb cyclones, it turns out, are storms that undergo “bombogenesis.”  What that means is a low-pressure area (in other words, a storm) that undergoes rapid strengthening and can be described as a weather bomb, or popularly, a bomb cyclone.

These things usually take place over remote tropical ocean areas but a really intense one struck the Pacific Northwest on October 24th.  The storm off the coast of Washington, with a barometric pressure reading equivalent to a category 4 hurricane, was the second extreme low-pressure storm in the North Pacific in a single week.  Both storms involved pressure drops of more than 24 millibars in 24 hours, making them bomb cyclones.

These storms brought high winds and extreme precipitation that doused wildfires and provided some relief to the extreme drought in Central and Northern California.  Along with these positive effects, however, the storms also caused power outages, flooding, landslides, and mud and debris that washed out roads.

The October 24-25 event brought 16.55 inches of rain to Mount Tamalpais in Marin County, California in a 48-hour period.  Sacramento got 5.44 inches of rain, breaking a 140-year-old record.  And the city had just broken another extreme weather record for the longest dry spell in history.

The storms directed streams of moisture from north of Hawaii toward the West Coast in long, narrow bands of moisture known as atmospheric rivers.  We are learning about all sorts of unfamiliar weather phenomena as extreme weather events become increasingly common.

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Extratropical Cyclones Drench West Coast

Photo, posted January 4, 2018, courtesy of NOAA/CIRA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drought And U.S. Hydropower | Earth Wise

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The ongoing severe drought in the western U.S. has led to low water levels in the rivers and reservoirs that feed hydroelectric power systems.  The Energy Information Administration is projecting a 13.9% decrease in hydroelectric generation this year compared to 2020.

Water levels in Lake Powell have fallen so low that it may not be possible to operate the power plant at Glen Canyon Dam starting as soon as 2022.  California officials took the Edward Hyatt hydroelectric plant offline in August because of low water levels on Lake Oroville.   Washington, the state with the most hydroelectric power generation, has seen an 11% drop in electricity generated to date this year as compared to last year.  That state is actually doing better than others in the West, such as California, where hydro generation is down 38%.

Hydropower accounts for over 7% of the electricity generated in the United States.  Five states – Washington, Idaho, Vermont, Oregon, and South Dakota – generate at least half of their electricity from hydroelectric dams.

The current decrease in hydropower is alarming, but it is not unprecedented.  The more significant question is whether the drop in generation this year is a sign that this power source is declining and becoming less reliable.   According to some scientists, the West is in a “megadrought” that could last for decades.

The greater concern is whether the bad years are likely to become more common because of climate change.  Climate projections agree that temperatures will continue to rise, but what will happen to precipitation levels in specific places is much less certain.  That is what will determine what the future holds for hydroelectric power.

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Inside Clean Energy: Drought is Causing U.S. Hydropower to Have a Rough Year. Is This a Sign of a Long-Term Shift?

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drought And Desalination | Earth Wise

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The Western US is currently experiencing what might be the worst drought in over 1,000 years.   The region has seen many droughts in the past, but the changing climate is making dry years drier and wet years wetter.   Diminishing snow-packs mean that rivers, streams, reservoirs, and soil are not replenished enough in the spring and summer.

Meanwhile, the Southwest has seen a growth rate over the past 60 years that is twice that of the rest of the country.  More and more people are moving to areas expected to get even drier in the years to come.  There have been unprecedented water allocation cuts from the Colorado River – which provides water to seven states – and there have been shutdowns of hydroelectric power plants.

Only three percent of the planet’s water is fresh water and much of that is not available for our use.  Over 120 countries have turned to desalination for at least some of their drinking water.  In the US, the largest plant is in Carlsbad, California and a huge new plant is likely to be built in Huntington Beach, California.

Desalination has its drawbacks.  It is expensive, consumes large amounts of energy, and has detrimental environmental impacts.  Most of the world’s desal plants now use membrane filtration technology but there are still many that use the thermal distillation method.

There are efforts around the world aimed at improving desalination.  A giant project in Saudi Arabia is based on solar heating of sea water.  The U.S. Army and the University of Rochester are working on a different solar-based system.  European companies are developing a floating seawater desalination plant powered by wind energy. 

Droughts seem to be here to stay.  Finding better ways to get fresh water is essential.

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A 1,000 Year Drought is Hitting the West. Could Desalination Be a Solution?

Photo, posted May 31, 2021, courtesy of Frank Schulenburg 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.

Wine And Wildfire Smoke | Earth Wise

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Rising global temperatures have made droughts and heatwaves more common and intense, leading to larger and more destructive wildfires.   In 2020, wildfires in California blackened more than 4 million acres, the largest wildfire season on record.   With its continuing drought, California has already had 1.5 million acres burned by wildfires this year, and the fires continue.

Wildfires can cause extensive damage throughout the agricultural industry by destroying crops and killing livestock.  But the fires can have a unique effect on the wine industry:  wine grapes can be affected by smoke taint.

Vineyards have demonstrated themselves to be good fire breaks.  They definitely help prevent the movement of wildfires.  But there is no way to stop smoke from the fires from drifting into vineyards.  By far, the damage caused by smoke far outweighs direct losses from fires in vineyards.

Winemakers sometimes add subtle smoky notes to their vintages by aging them in toasted oak barrels.   But wildfire smoke permeating vineyards – even from distant blazes – can end up making wines undrinkable.  Smoke-tainted wines end up having unpleasant aromas that people describe as being like disinfectants or burnt rubber. 

With wildfires an increasingly persistent presence in California, the state’s $43 billion wine industry is facing a major challenge.  An estimated 165,000 to 325,000 tons of California wine grapes went unharvested last year, adding up to more than $600 million in losses from fire and smoke.  The industry will need to figure out ways to detect and manage smoke taint as the problem isn’t going to go away.

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Wildfire Smoke: An Emerging Threat to West Coast Wines

Photo, posted July 25, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

RNA Modification For Plants | Earth Wise

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We have heard a lot about RNA this past year as messenger RNA vaccine technology has been used for the first time to combat the Covid-19 pandemic.  Now RNA-based technology has shown promise to make major contributions to agriculture.

A group of researchers at the University of Chicago and two Chinese universities have announced that manipulating RNA can allow plants to yield dramatically more crops as well as have better drought resistance.

Adding  gene encoding for a protein called FTO to both rice and potato plants increased their yield by 50% in initial field tests.  The plants were larger, produced longer root systems, and could better tolerate drought conditions.  Further analysis showed that the plants had increased their rate of photosynthesis.

FTO protein erases chemical marks on RNA.  Specifically, it controls a process known as m6A, which is a key modification of RNA.  The FTO erases m6A to reduce some of the signals that tell plants to slow down and reduce growth.  Plants modified with the addition of FTO produced significantly more RNA than control plants.

Experiments with both rice plants and potato plants – which are completely unrelated – demonstrated the same results, indicating that the technique could be broadly applicable.  (The genetic modification is rather simple to make and has worked with every type of plant the researchers have tried it with so far).

These results are just the beginning but demonstrate the potential of a technology that could help address problems of poverty and food insecurity at a global scale as well as responding to climate change.  The world depends on plants for everything from wood, food, and medicine, to flowers and oils. This technique has the potential to dramatically increase the stock material we can get from most plants.

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RNA breakthrough creates crops that can grow 50% more potatoes, rice

Photo, posted September 22, 2014, courtesy of Toshiyuki Imai via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Dangerous Fire Season | Earth Wise

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The western United States is entering the fire season under much worse drought conditions than last year.  Last year, 15,800 square miles burned in the U.S., mostly in the West.

The western U.S. is in the midst of a 20-year mega-drought.  Rainfall in the Rocky Mountains and farther west was the second lowest on record this April.  The soil in the western half of the country is the driest it has been since 1895.

The situation is particularly bad in California and the Southwest.  In March, less than a third of California was experiencing extreme or exceptional drought.  Now, 73% of the state is.  A year ago, a record-breaking fire season burned 4% of the state and, at that time, only 3% of California was in a state of extreme drought.

A year ago, no parts of Arizona, Nevada, or Utah were in extreme or exceptional drought.  Now, more than 90% of Utah, 86% of Arizona, and 75% of Nevada face severe drought conditions.  At this time last year, only 4% of New Mexico faced extreme drought but 77% does now.

These extreme drought conditions, which are believed to be linked to climate change, are causing increased tree mortality among many species, ranging from junipers in the Southwest even to drought-tolerant blue oaks in the San Francisco Bay Area.

Conditions are extremely ripe for a lot of forest fire this year.  Last year was a terrible year for wildfires in the West and we are heading into a fire season with much drier fuels than there were last year.  The risks of great damage from wildfires are higher than ever.

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US West Enters Fire Season Facing Extremely Dry Conditions

Photo, posted September 18, 2020, courtesy of USFS/National Interagency Fire Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

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The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world.  In Mexico, the pads are known as nopales and are used in a variety of dishes.  The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops.  Cactus pear can be used for both human consumption and livestock feed.  As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear.  The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid.  There is enormous potential for planting cactus for carbon sequestration.  If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Widespread Drought | Earth Wise

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As the U.S. enters the last part of the summer, fully one-third of the country is experiencing at least a moderate level of drought.   Much of the West is reaching severe drought conditions and New England has been unusually dry and hot.  In total, over 50 million Americans are living in drought-affected areas.

According to the U.S. Drought Monitor program, more than 93% of Utah, Colorado, Nevada, and New Mexico are experiencing drought to some degree.  More than 60% of both Utah and Colorado are in severe drought.   More than three-quarters of Oregon, Arizona, and Wyoming are also in drought.  And most of these areas had no sign of drought this time last year.

Severe drought conditions result in stunted and browning crops, limited pasture yields, dust storms, reduced well water levels, and an increase in the number and severity of wildfires.

Warm air temperatures and minimal snowfall in spring set the stage for this summer’s drought conditions.  A ridge of high pressure over the northeastern Pacific Ocean pushed the jet stream farther north than usual.  And, once again, there has been a failure of the southwestern monsoon in Arizona and New Mexico and the Four Corners region.  Monsoon rains provide half of the year’s precipitation in many of those areas. 

Instead, there has been extreme heat in the region.  Phoenix has already smashed the record for the most days over 110oF in a calendar year (42 as of August 18), with five months to go.  Las Vegas hasn’t seen measurable rainfall since April, and Cedar City, Utah has recorded a record low of 0.05 inches of rain this summer.

Conditions are not expected to get better for a couple of months.

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A Third of the U.S. Faces Drought

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conserving The Colorado River | Earth Wise

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Last year, we talked about the troubles facing the Colorado River.  Nearly two decades of drought conditions have reduced the water levels of the two largest reservoirs of Colorado River water and have threatened the water supply of millions of people in the region.  Clear scientific evidence shows that climate change is constricting the iconic river and will do further damage as temperatures rise.

Faced with these facts, water resource managers have been implementing conservation policies in the region and the results so far are very encouraging.

The use of Colorado River water in the three states of the river’s lower basin – Arizona, California, and Nevada – fell to a 33-year low in 2019.  The three states consumed just over 6.5 million acre-feet for the year, which is about 1 million acre-feet less than the three states are entitled to use under the legal agreement that allocates Colorado River water.

The last time water consumption from the river was that low was in 1986, which is the year that Arizona opened a large canal that extracts river water for its entitlement. 

A key indicator of river health is the depth of Lake Mead, the largest reservoir of Colorado River water.  It has been steadily dropping in recent years, but last year, with the reduced consumption, the water level actually increased by 12 feet.

According to water managers, the steady drop in water consumption in recent years is a sign that conservation efforts are working and that there are strategies that can deal with chronic shortages on the river in the future.  It represents an important demonstration that it is possible to use less water in a region that irrigates 5 million acres of farmland and has 40 million people in 2 countries and 29 tribal nations.

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Remarkable Drop in Colorado River Water Use a Sign of Climate Adaptation

Photo, posted July 7, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Expensive And Dangerous Storms | Earth Wise

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Severe storms are getting more and more common.  Early in July, the United States experienced its 10th billion-dollar weather disaster of the year – the earliest this has happened.  It also marks 2020 as the sixth consecutive year with at least 10 such extreme weather events, which is also a record.  With the country struggling with the effects of a global pandemic, extreme weather is pretty much the last thing we need.

This year’s 10 storms have primarily consisted of tornadoes, damaging winds, and hail.  Seven out of the 10 storms were in the South or Southeast.  An Easter Sunday outbreak in that region saw 190 tornadoes and 36 people were killed that day.

Since 1980, the US has averaged nearly 7 billion-dollar weather disasters per year.  But the last five years have seen nearly 14 severe storms on average.  The way things are going this year, there will probably be more than that number.

This year’s growing total does not include the looming hurricane season, which is widely predicted to be more active than usual.  Because so many places in the South are still recovering from earlier disasters, they are particularly vulnerable to the effects of an active hurricane season.

Meanwhile, much of the country is suffering from drought conditions, making wildfires a major concern.  Recent years have seen deadly and destructive wildfires in many places, notably in California two years ago.  Between hurricanes and wildfires, the prospects are alarming for what could turn out to be a disastrous year for expensive and dangerous severe weather.

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US hits 10th billion-dollar weather disaster of the year — at a record pace

Photo, posted March 3, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)