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Geothermal Energy Storage | Earth Wise

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About 12% of the energy consumed by humanity is used to heat and cool homes and businesses.  A study by researchers at Lawrence Berkeley National Laboratory and Princeton University looked at a novel approach to making use of underground water to maintain comfortable temperatures and reduce consumption of natural gas and electricity.

The idea is to use aquifer thermal energy storage (known as ATES) to provide both heat in the winter and cooling in the summer.  The concept leverages the heat-absorbing property of water and natural geological features.  The idea is to pump up water from existing underground reservoirs and heat it at the surface using environmental heat or even excess energy from solar or wind generation.  Then the warm water is pumped back down. It stays warm for a long time – even months – because the earth is a good insulator.  When the water is pumped back up in the winter, it is much hotter than the ambient air and can be used to supply heat to buildings.

Alternately, water can be pumped up and cooled in the winter and then put back down underground and stored until cooling is needed in the summer months.

This technology has not been used much in the US, but it is gaining recognition internationally, particularly in the Netherlands.  It can perform very well in areas with large seasonal fluctuations.

The research study used modeling and various simulations to estimate how much energy ATES could save on the US grid.  The results showed that adding ATES to the grid could reduce consumption of petroleum products for heating and  cooling by up to 40%.  The system could also help prevent blackouts by reducing high power demand during extreme weather events.

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Underground Water Could be the Solution to Green Heating and Cooling

Photo, posted February 19, 2012, courtesy of Sanjay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record Low Antarctic Sea Ice | Earth Wise

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Recent satellite observations of the sea ice in the Antarctic found the lowest level of ice cover ever seen in the forty years that these observations have been made.  As of February 8th, there were only 849,000 square miles of the Southern Ocean covered with ice.  The previous record low was measured last February 24th when the total coverage was 876,000 square miles.  Ice melting was likely to continue as the month went on.

This past January had already set a new record for that month’s mean extent of ice coverage at 1.24 million square miles. This rapid decline in sea ice has been going on for the past six years and is very unusual.  Average Antarctic ice cover hardly changed at all during the previous thirty-five years.

Antarctic sea ice generally reaches its maximum extent in September or October and its minimum extent in February.  At its maximum, the sea ice cover in the Antarctic is generally between 6.9 and 7.7 million square miles.   On the other hand, there are some places where the sea ice melts completely during the Southern Hemisphere summer.  Sea ice varies much more in the Antarctic than in the Arctic where the ice is much thicker.

Climate warming at the poles is much higher than at lower latitudes.  Nonetheless, it is not yet clear whether what we are seeing is the beginning of the end of summer sea ice in the Antarctic, or whether this is just a new phase characterized by low but still stable sea ice cover in the summer.

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Record low sea ice cover in the Antarctic

Photo, posted January 24, 2012, courtesy of Rob Oo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Disappearing Glaciers | Earth Wise

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Glaciers are massive bodies of slowly moving ice.  Glaciers form on land, and represent the snows of centuries compressed over time.  They move slowly downward under the influence of their own weight and gravity. 

Most of the glaciers on the planet are found in the polar regions, including Antarctica, the Canadian Arctic, and Greenland.  Glaciers can also be found closer to the equator in mountain ranges, such as the Andes Mountain range in South America.  Glaciers are always changing, accumulating snow in the winter and losing ice to melting in the summer.  But in recent times, the melting has been outpacing the accumulation.

A new international study led by researchers at Carnegie Mellon University’s College of Engineering has produced new projections of glacier loss through the century under different emissions scenarios.  According to the projections, the world could lose as much as 41% of its total glacier mass this century – or as little as 26% – depending on climate change mitigation efforts. 

In a future with continued investments in fossil fuels (sometimes referred to as the “business as usual” scenario), more than 40% of the glacial mass will be gone by 2100, and more than 80% of glaciers by number could disappear.  Even in a best case scenario where the increase in global mean temperature is limited to 1.5° degrees Celsius relative to pre-industrial levels, more than 25% of glacial mass will be gone, and nearly 50% of glaciers by number will disappear.

Glaciers take a long time to respond to changes in climate.  A complete halt to emissions today would take anywhere from 30 to 100 years to be reflected in glacier mass loss rates.

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Team projects two out of three glaciers could be lost by 2100

Ice, Snow, and Glaciers and the Water Cycle

Photo, posted August 13, 2010, courtesy of Kimberly Vardeman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Hot Year In Europe | Earth Wise

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This past summer was marked by some devastating heat waves in Europe.  Through November, the UK, Germany, and France have experienced their hottest year on record.

The UK has experienced its warmest year since 1884 and, in fact, all the top ten warmest years on record have occurred since 2002.

In France, the average temperature for the year is a few tenths of a degree higher than the  previous record, which was set in 2020.

In Germany, the first 11 months of the year saw a record for average temperature.  Its previous record was also set in 2020.

All three countries saw a spike in heat-related mortality as result of the summer heatwaves.  England and Wales reported 3,271 excess deaths during the summer.  France reported 2,816 excess deaths during its three heat waves.  In Germany, an estimated 4,500 people died as a result of extreme heat.

There are multiple effects of climate change which include more frequent heat waves in Europe.  A recent study showed that European summers are warming twice as fast as the global average.  In fact, summer temperatures across much of the European continent have already risen by 3.6 degrees Fahrenheit or 2 degrees Celsius, which is the feared level of global climate increase that nations around the world are trying to stave off.

Worldwide, 2022 will rank among the top ten warmest years on record but will most likely not be the warmest.   That being said, the past eight years are on track to be the eight warmest years on record.  The US will also see one of its ten warmest years, although not the warmest.

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UK, Germany, France on Pace for Their Hottest Year on Record

Photo, posted April 23, 2022, courtesy of Jose A. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Europe Is Warming Faster Than The Rest Of The Planet | Earth Wise

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A new study by researchers at Stockholm University has found that the warming during the summer months in Europe has been much faster than the global average.  The findings, published in the Journal of Geophysical Research Atmospheres, are that the climate across the European continent has become drier, particularly in southern Europe, leading to worse heat waves and an increased risk of fires.

Warming over land areas occurs much faster than over oceans.  The global average warming to date is 1.6 degrees Celsius over land and 0.9 degrees over oceans.   This means that the global emissions budget to keep warming below 1.5 degrees has already been used up over land.  The new study in fact shows that the emissions budget to avoid 2 degrees of warming has already been exceeded over large parts of Europe during the summer half-year (April to September).

This accelerated warming in Europe has led to more frequent heat waves.  These, in turn, increase the risk of fires, such as the devastating fires in southern Europe this past summer.

Southern Europe has been experiencing a positive feedback situation in which the ongoing warming has been amplified because of drier soil and decreased evaporation.  Added to that, there has been less cloud coverage over large parts of Europe, probably as a result of less water vapor in the air.

The study also looked at the impact of aerosol particles on temperatures in Europe.  As the amount of relatively short-lived aerosol particles has decreased with the reduction of coal-fired power plants, the temporary cooling effects of those particles partially masking the underlying warming trend have diminished.  In contrast, carbon dioxide emissions stay in the atmosphere for centuries.

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Large parts of Europe are warming twice as fast as the planet on average

Photo, posted April 18, 2020, courtesy of Roman Ranniew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Glacial Loss In The Swiss Alps | Earth Wise

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In 2022, glaciers in the Swiss Alps melted more than in any year on record.   This is the latest piece of bad news for the country’s glaciers, which have lost more than half of their volume of ice since the 1930s.

The melting season for Switzerland’s snow and ice typically starts in May and ends in early October.  This year’s melting season caused glaciers in the Diablerets mountain group to thin by an average of 13 feet, which is 3 times the amount of thinning observed over the past decade.   The Tsanfleuron pass between two of the glaciers is now exposed as bare rock for the first time in several thousand years. Across Switzerland, glaciers lost about 6% of their remaining volume just this year.  The previous worst year for glaciers was 2003, when losses were nearly 4%. 

There was significant melting this year in part because of the small amount of snowfall over the winter.  That snow melted quickly, being sped up by the warming effect of dust from the Sahara Desert falling on the snow.  By early summer, there was no longer a protective blanket of snow on the glaciers, exposing them to summer heat.

The loss of glaciers is far more serious than the disappearance of aesthetically pleasing landscape features.   Glaciers act as reservoirs of water that persist through the summer months.  Melt from glaciers provides water to ecosystems and creates habitats for plants and animals.  Cold runoff from glaciers affects downstream water temperatures which have a major impact on insects, fish, and other creatures.  Globally, melting glaciers contribute more than 20% of the observed ongoing sea-level rise.

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Rocky Road for Swiss Glaciers

Photo, posted June 22, 2015, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Global Stilling | Earth Wise

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During the summer of 2021, much of Europe experienced a “wind drought” – wind speeds in many places were about 15% below average.  In the UK in particular, winds were unusually calm and wind energy production was dramatically reduced.

Globally, wind speeds have been dropping by about 2.3% per decade since the 1970s.  In 2019, however, global average windspeeds actually increased by about 6%.  The question is whether a trend of slowing winds – so-called global stilling – is associated with climate change or is just natural variability in action.

Wind results from uneven temperatures in air masses.   Much of the world’s wind comes from the difference between the cold air at the poles and the warm air at the tropics.  Because the Arctic is warming much faster than the tropics, it is possible that winds will continue to decline around the world. 

Another factor people cite is the increase in surface roughness.  The number and size of urban buildings continues to increase, which acts as a drag on winds.

Some models predict that wind speeds will decrease over much of the western U.S. and East Coast, but the central U.S. will see an increase.  Experts do not all agree about what is happening with global winds.  Many believe that the observed changes to date have been within the range of variability.  Furthermore, some places have been windier than usual.

All of this really matters for many reasons.  Europe is increasingly dependent upon wind power as an alternative to fossil fuels.  A 10% drop in wind speed results in a 30% drop in energy generation.   Whatever their cause may be, wind droughts cannot be ignored.

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Global ‘Stilling’: Is Climate Change Slowing Down the Wind?

Photo, posted June 28, 2008, courtesy of Patrick Finnegan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Low Fares Clean German Air | Earth Wise

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Germany’s parliament set summer public transport fares at 9 euros a month as a way to slash pollution and reduce imports of Russian oil.   The low price included all buses, trams, subways, and regional trains, effectively lowering prices by more than 90% in some cities.  Berliners saved 98 euros on their monthly travel pass; commuters in Hamburg saved even more.

The program began June 1 and ended August 31.  The bargain rates drove widespread use of public transport and discouraged the use of cars, which already was undesirable due to high gasoline prices.   Over the three-month period, transit authorities sold over 50 million subsidized tickets.  One out of five travelers were using public transport for the first time, according to surveys.

According to an estimate from the Association of German Transport Companies, the program helped to avoid 1.8 million tons of carbon dioxide emissions.  This is roughly equivalent to taking 1.5 million cars off the road for the summer or planting 30 million trees.

The discount transit program had a clearly positive effect on the climate and, obviously, was a source of financial relief for German citizens.  Last year, Germany was the largest buyer of Russian oil in Europe and it wanted to make drastic reductions in its purchases.  The success of the program prompted many to ask for it to be continued.  However, the program cost the government about 2.5 billion euros in reimbursements to transit companies.  The German government has said it would not be extended.

Nonetheless, German policymakers are weighing other proposals for low-cost public transit.  Clearly encouraging people to use public transit pays dividends.

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Germany’s Cheap Summer Train Fares Prevented 1.8 Million Tons of Carbon Pollution

Photo, posted June 6, 2022, courtesy of 7C0 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More Bleaching In The Great Barrier Reef | Earth Wise

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Australia’s Great Barrier Reef is an ecosystem that can be seen from space.  It has now suffered its 6th mass coral bleaching event since 1998.  Previous events happened in 1998, 2002, 2006, 2016, and 2017.  This latest bleaching has occurred even though this is a La Niña year, when more rain and cooler temperatures are supposed to help protect delicate corals.

An aerial survey of 750 separate reefs across much of the 1500 mile-long Great Barrier Reef system found severe bleaching among 60% of the corals.  The bleaching covers an area even wider than the back-to-back outbreaks in 2016 and 2017.

The bleaching is a product of a summer in Australia that started early.  December temperatures were already warmer than the historical February summer maximums.  Globally, 2021 was the hottest year on record for the world’s oceans for the sixth year in a row.

Bleached coral can recover if temperatures cool down for a long enough period, but this is becoming increasingly rare.  Between 2009 and 2019, 14% of the world’s coral reefs were lost for good.

In Australia, the plight of the Great Barrier Reef has become politicized.  The current government is not supportive of efforts to reduce the country’s fossil fuel dependence and has worked to keep the reef from being placed on the list of endangered world heritage sites.  Instead of pushing for emissions cuts, Australia has focused on a variety of long-shot projects aimed at helping the reef.

The fact is that coral reefs cannot cope with the current rate of warming and unless that slows down soon, they will simply not survive for long.

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Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Smart Roof | Earth Wise

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Scientists at the Lawrence Berkeley Laboratory have developed an all-season smart roof coating that can keep homes warm during the winter and cool during the summer, and the coating does not consume any gas or electricity.

Existing cool roof systems consist of reflective coatings, membranes, shingles, or tile that lower house temperatures by reflecting sunlight as well as emitting some of the absorbed solar heat away from the roof as infrared radiation.  The problem with such systems is that they continue to radiate heat during the winter, which actually drives up heating costs.

The new material is called a temperature-adaptive radiative coating or TARC.  It enables energy savings by automatically turning off the radiative cooling in the winter.  TARC reflects about 75% of sunlight year-round, but its thermal emittance is high when the temperature is warm – promoting heat loss to the sky – but decreases in cooler weather, helping to retain the heat in a building.

The researchers produced thin-film TARC material that looks like Scotch tape that could be affixed to a surface like a rooftop.  They applied the material to a balcony alongside a sample of commercial dark roof material and a sample of commercial white roof material.

In experiments simulating 15 different climate zones across the US, they found that the TARC material outperforms existing roof coatings for energy savings in 12 out of the 15 zones, particularly in regions with wide temperature variations between day and night, such as in the San Francisco Bay Area, or between winter and summer, such as New York City.

The researchers believe that installing TARC coatings on roofs would save the average U.S. household about 10% in utility costs.

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New Smart-Roof Coating Enables Year-Round Energy Savings

Photo, posted May 18, 2017, courtesy of Damian Gadal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Could Lyme Disease Be Eradicated? | Earth Wise

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Tiny ticks are a big problem.  Measuring only three to five millimeters in size, ticks are widely distributed around the world.  They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

According to estimates from the Centers for Disease Control and Prevention, ticks infect an estimated 476,000 people with Lyme disease in the United States every year.  Lyme disease is caused by a bacterium called Borrelia burgdorferi that lurks in wild mice. Ticks that feed on the mice become infected and can then in turn infect people and animals.   

The disease is not only a problem in the United States, but in other parts of North America, Europe and Asia as well.  It often causes a characteristic “bullseye” rash and flu-like symptoms. If left untreated, it can lead to serious long-term health problems.

Currently, lyme disease is treated using antibiotics.  But antibiotics kill a wide range of bacteria – including healthy gut bacteria – which can lead to additional health issues and more antibiotic resistance.

A recent discovery by researchers from Northeastern University in Boston could allow Lyme disease to be eradicated in the wild.  The researchers found that a compound called hygromycin A is deadly to the bacterium that causes Lyme disease but harmless to animals and has little effect on most other bacteria. 

The little-known antibiotic cleared Lyme disease infection in mice, both when administered via injection and when ingested using bait.  As a result, dropping feeding baits could eradicate Lyme disease from whole areas or even entire countries.  The first field trial will be next summer.

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Drug treatment for Lyme disease could lead to its eradication

Photo, posted June 21, 2017, courtesy of NIAID via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metals In Western Water Supplies | Earth Wise

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A new study published by the University of Colorado Boulder looked at the problem of rivers being contaminated by acid rock drainage.  Rocks that include sulfide-based minerals, such as pyrite, oxidize when exposed to air and water.  The resulting chemical reaction produces sulfuric acid which, when present in water, dissolves metals like lead, cadmium, and zinc.  The recent study found that rare earth elements are also leached out of rock by this process.

Rock drainage occurs naturally throughout the western United States, but historic mines that disturbed large amounts of rocks and soil have dramatically increased this process and have led to growing downstream water pollution.  Upwards of forty percent of the headwaters of major rivers in the West are contaminated by some form of acid mine or rock drainage.

The warming climate has brought longer summers and less snow in winters.  Longer, lower stream flows make it easier for metals to leach into watersheds and concentrate the metals that would otherwise be diluted by snowmelt.

Rare earth elements are essential components of many high-tech devices such as computers, hard drives, and cell phones.  There is not a long history of studying the hazards they might represent when they enter the environment.

The study looked at the Snake River watershed in Colorado and found that increasing amounts of rare earth elements are entering Colorado water supplies.  Concentrations of rare earth elements are not ordinarily monitored and there are no water quality standards set for them.

According to the researchers, once rare earth elements get into water, they tend to stay there.  Traditional treatment processes don’t remove them.  It is a growing problem that needs to be addressed.

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Rare earth elements and old mines spell trouble for Western water supplies

Photo, posted October 27, 2007, courtesy of Dion Gillard 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.

Wildfires And The Climate | Earth Wise

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Scientists from the National Center for Atmospheric Research recently published a study analyzing the events that influenced the world’s climate in 2020.  Among these were the pandemic-related lockdowns that reduced emissions and resulted in clearer air in many of the world’s cities.

While this was a significant event, the study found that something entirely different had a more immediate effect on global climate:  the enormous bushfires that burned in Australia from late 2019 to 2020, producing plumes of smoke that reached the stratosphere and circled much of the southern hemisphere.

Those fires sprung up in September 2019 and lasted until March 2020.  The fires burned more than 46 million acres (about 72,000 square miles), which is roughly the same area as the entire country of Syria.  Thousands of homes and other buildings were lost.

Major fires inject so many sulfates and other particles into the atmosphere that they can disrupt the climate system, push tropical thunderstorms northward from the equator, and potentially influence the periodic warming and cooling of tropical Pacific Ocean waters known as El Nino and La Nina.

According to the study, the COVID-19 lockdowns actually had a slight warming influence on global climate, as a result of clearer skies enabling more heat to reach the earth’s surface.  In contrast, the Australian bushfires cooled the Southern Hemisphere because the atmospheric particles reflected some of the incoming solar radiation back to space.

This summer, there have been raging wildfires in the western US and Canada, which have affected air quality in many parts of the nation and have been a serious health hazard.  Undoubtedly, these fires are influencing the climate system as well in ways that we are still trying to understand.

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Bushfires, not pandemic lockdowns, had biggest impact on global climate in 2020

Photo, posted January 18, 2020, courtesy of BLM-Idaho via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tracking Ocean Plastics | Earth Wise

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Plastic pollution in the oceans is a major problem.  An estimated 8 million tons of plastic trash enters the ocean every year.  Most of it is broken up by sun and waves into microplastics, which are tiny bits that ride currents for hundreds or thousands of miles.  All of this debris is harmful to marine ecosystems, and it is both challenging to track and very difficult to clean up.

University of Michigan researchers have developed a new technique for spotting and tracking ocean microplastics across the globe.  The approach relies on the Cyclone Global Navigation Satellite System, or CYGNSS, which is a constellation of eight microsatellites launched in 2016 to monitor weather near large storm systems.  It turns out that the radar systems on CYGNSS that measure surface roughness to calculate the wind speed near the eyes of hurricanes can also be used to detect the presence of microplastics.

With the satellite measurements, the researchers have found that global microplastic concentrations tend to vary by season, peaking during the summer months.  For example, June and July are the peak months for the Great Pacific Garbage Patch.  The data also showed spikes in microplastic concentration at the mouth of China’s Yangtze River, long suspected to be a chief source of plastic pollution.  The researchers produced visualizations that show microplastic concentrations around the world.

The information provided by the new technique could help organizations that clean up microplastics to deploy ships and other resources more efficiently.  Data of single-point release of plastics, such as from rivers, may also be useful to UNESCO, which has sponsored a task force to find new ways to track the release of microplastics into the world’s waters.

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Ocean microplastics: First global view shows seasonal changes and sources

Photo, posted April 3, 2018, courtesy of Rey Perezoso via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Heat In The Arctic | Earth Wise

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By mid-November, the Arctic stays dark around the clock and twilight does not return until the end of January.  But even as winter darkness descended upon the Arctic this year, record-breaking high temperatures in the region continued.  In late November, temperatures across the entire Arctic basin were 12 degrees Fahrenheit above normal and some locations saw temperatures as high as 30 degrees above normal.

The entire summer and fall in the Arctic were characterized by exceptionally warm temperatures.  In June, the Siberian town of Verkhoyansk – located north of the Arctic Circle – registered a high temperature of 100.4 degrees.  The refreezing of the Arctic Ocean was greatly delayed this year.  The Northeast Passage along the Siberian Coast remained navigable for a record 112 days before freezing in November, breaking the previous record by more than a month.  The extent of sea ice covering the Arctic Ocean in October was the lowest ever recorded for that month.

The strongest warming occurring in the Arctic is during the fall.  That is because rapidly disappearing sea ice is enabling the dark waters of the Arctic Ocean to absorb heat in the summer and then radiate it back into the atmosphere until late in the fall.  The Arctic region is heating up three times faster than the rest of the planet, which has led to the volume of sea ice decreasing by 2/3 in the past 40 years.

According to researchers, the extreme heat in Siberia this year would have been virtually impossible without human-caused climate change and became 600 times more likely because of human emissions of greenhouse gases.

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Record-shattering Warmth Pushes Arctic Temperatures to 12 Degrees F Above Normal

Photo, posted September 1, 2009, courtesy of the U.S. Geological Survey via Flickr. Photo Credit: Patrick Kelley, U.S. Coast Guard.

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.

Dust From The Sahara | Earth Wise

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A vast cloud of dust from the Sahara Desert blanketed the Caribbean in late June before drifting across the southeastern U.S.  The phenomenon is nothing new; only the magnitude of the occurrence this time around was unusual.  According to experts, this is the most significant Sahara dust event in 50 years.

The Sahara Desert is the major source on Earth of mineral dust, with some 60-200 million tons of it per year being lifted into the atmosphere.  Convection currents over hot desert areas lift the dust to very high altitudes.  From there, it can be transported worldwide by winds.   The dust, combined with the extremely hot, dry air of the Sahara Desert often forms an atmospheric layer called the Saharan Air Layer, which can have significant effects on tropical weather by interfering with the development of hurricanes.  The Saharan Air Layer typically moves across the North Atlantic every three to five days from late spring to early fall, peaking in the middle of the summer.  It can occupy a layer as much as two miles thick in the atmosphere.

The dust plume this summer was highly visible from space, covering thousands of miles of the Atlantic Ocean and the Caribbean Sea.

A common effect of Sahara dust is that normally blue skies can acquire a milky haze, but beyond that can lead to spectacular sunsets.  But apart from the visual spectacle, the dust can aggravate the conditions of people with asthma, respiratory illnesses, and allergies. On the positive side, as long as the dust is around, it is much less likely that tropical storms and hurricanes will form.

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Sahara dust blankets Caribbean, air quality hazardous

Photo, posted June 22, 2020, courtesy of Sagar Rana via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Dead Zone In The Gulf Of Mexico | Earth Wise

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The Gulf of Mexico has an area of low to no oxygen in the water that can kill fish and other marine life.  It is an annual event that is primarily caused by excess nutrient pollution from human activities in urban and agricultural areas throughout the Mississippi River watershed.   When these excess nutrients reach the Gulf, they stimulate the overgrowth of algae, which eventually die and decompose, depleting the oxygen in the water as the algae sink to the bottom.

These low oxygen levels near the bottom of the Gulf cannot support most marine life.  Some species – among them many fish, shrimp, and crabs – swim out of the area, but animals that can’t swim or move away are stressed or killed by the low oxygen.  The dead zone in the Gulf occurs every summer.

A recent forecast for this summer’s dead zone predicts that the area of low or no oxygen will be approximate 6,700 square miles, which is roughly the size of Connecticut and Delaware combined.  This is about 1,100 square miles smaller than last year’s dead zone and much less than the record of 8,776 square miles set in 2017.  But it is still larger than the long-term average size of 5,387 square miles.

Making comparisons to the long-term average ignores the fact that the long-term average itself is unacceptable.  The dead zone not only hurts marine life, but it also harms commercial and recreational fisheries and the communities they support.  The actions that have been taken so far to reduce pollution in the Mississippi watershed are clearly not sufficient to drastically reduce the dead zone in the Gulf.

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Large ‘dead zone’ expected for Gulf of Mexico

Photo, posted October 17, 2017, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antarctica’s Hot Summer | Earth Wise

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The Southern Hemisphere’s recent summer brought drought, heatwaves and bush-fires that ravaged Australia.  At the same time, Antarctica experienced a summer of extreme weather.

In East Antarctica, the Casey research station in the Australian Antarctic Territory had its first heatwave event, recording extreme maximum and minimum temperatures over three consecutive days in January.  Record high temperatures were also reported at bases on the Antarctic Peninsula.

The Casey station recorded a record high maximum temperature of 49 degrees Fahrenheit and a record overnight low of 36 degrees.  In February, Brazilian scientists reported a high temperature of 69 degrees at Marambio, an all-time record for Antarctica.

Ecologists say that the hot summer would most likely lead to long-term disruption of local populations, communities, and the broader ecosystem.  That disruption could be both positive and negative.

Most life in Antarctica exists in small ice-free oases and depends on melting snow and ice for a water supply.  Melt water from the warming temperatures will lead to increased growth and reproduction of mosses, lichens, microbes and invertebrates.

However, excessive flooding can dislodge plants and alter the composition of communities of invertebrates and microbial mats. If the ice completely melts early in the season, then ecosystems will suffer drought for the rest of the season.

Extreme events often have impacts for years after the event.  There will be long-term studies of the areas affected by the recent Antarctic heat wave. Such extreme events associated with global climate change are predicted to increase in frequency and impact, and even the most remote areas of the planet are not immune to them.

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Antarctica’s summer of extreme heat

Photo, posted January 30, 2014, courtesy of Andreas Kambanis via Flickr

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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