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Saharan dust and solar power

May 29, 2025 By EarthWise Leave a Comment

The world is a big place but even things that are far away can have serious local consequences. The effects of distant Canadian wildfires on air quality in Florida is a good example.

Europe is increasingly becoming reliant on solar energy to meet its targets for climate change mitigation and energy security. According to new research by four Hungarian universities, mineral dust carried on the wind from the Sahara Desert is not only reducing electricity generation from solar power across Europe but it is also making it harder to predict what gets generated.

The Sahara releases billions of tons of fine dust into the atmosphere each year. Tens of millions of tons reach European skies where the tiny particles scatter and absorb sunlight, reduce the amount of light reaching the surface, and even promote cloud formation. All of these things reduce the output of photovoltaic systems.

In addition, conventional weather forecasting tools don’t consider the effects of Saharan dust events, so that scheduling of solar power for the energy system becomes less reliable. Incorporating these events into new forecast models will be essential.

Apart from the atmospheric effects of the dust, there are also long-term impacts due to dust contaminating and eroding the physical infrastructure of solar panels thereby further reducing their efficiency and increasing maintenance costs.

Over time, south-to-north transport of Saharan dust is likely to become more pronounced due to a steeper thermal gradient. Currently, the quantities of atmospheric dust, the dynamics of its transport, and the physical properties of the dust itself are not very well understood. Understanding these things will be crucial for Europe’s energy future.

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The shadow of the wind: photovoltaic power generation under Europe’s dusty skies

Photo, posted March 11, 2023, courtesy of Mark Wordy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and orchard health

November 1, 2024 By EarthWise Leave a Comment

The frequent and massive megafires in places like Canada and the American west have led to a lot of research on the impact of smoke on humans but there has been less study of the effects of smoke on plant health. Researchers at the University of California, Davis have found that trees are just as vulnerable as humans are to the harmful effects of long-term exposure to smoke.

The Davis researchers studied almond, pistachio, and walnut trees at 467 orchard sites in California’s Central Valley from 2018 to 2022. In 2022, so-called megafires burned more than 4.2 million acres in California, pouring ash and smoke into the sky. The researchers had been studying how trees store carbohydrates to cope with heat and drought.

With the onset of the fires, they saw an opportunity to study how smoke affects carbohydrate levels. Trees use stored carbohydrates to sustain them through winter dormancy and spring growth. Trees produce carbohydrates via photosynthesis and thick smoke blocks the amount of light reaching the trees. Beyond that, there are other aspects of wildfire smoke, such as particulate matter and ozone that appear to affect photosynthesis.

The team found that the smoke not only reduced the amount of carbohydrates in trees but also caused losses that continued even after the fires were extinguished. This led to nut yield decreases of 15% up to 50% in some orchards. The researchers expected to see some impact on the trees during periods when smoke was really dense but were not expecting the smoke to have such a lingering effect and result in a significant drop in yield.

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Smoke From Megafires Puts Orchard Trees at Risk

Photo, posted October 1, 2008, courtesy of Suzi Rosenberg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Balloon release laws

May 27, 2024 By EarthWise Leave a Comment

The Florida state legislature has recently passed a law that bans the intentional release of helium balloons outdoors. It is a rare example of a bipartisan piece of legislation. Florida is joining six other states that have already enacted balloon restricting laws.

Balloons released into the sky don’t just disappear into the ether. They often end up in oceans and waterways and the thin material that remains is 32 times more likely to kill seabirds than other types of plastic debris. Aquatic animals often mistake balloons for jellyfish and fill up on them. Balloons tied up with ribbons entangle turtles and manatees. Even grazing cows have died from ingesting balloons. Balloons contribute to microplastic pollution, which is a growing problem for all living things, including humans.

Other states with balloon release laws are Connecticut, Tennessee, New York, Texas, California, and Virginia. Details of the laws vary. They carve out exceptions for specific applications. They exempt small children. Some limit the quantity of balloon release. Others require balloons to be weighted down to prevent them from rising too high. California’s legislation is aimed at the metallized mylar balloons that have shorted out high-tension electrical wires and triggered wildfires.

The Florida law equates intentionally releasing a lighter-than-air balloon with littering. It’s a non-criminal offense that carries a fine of $150.

People enjoy releasing helium balloons, particularly en masse. The spectacle has become part of weddings, gender reveal parties, and even funerals. But the practice has serious environmental repercussions, and its restriction is being pursued by more and more states and municipalities.

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Up, Up and Not OK: Letting Go of Balloons Could Soon Be Illegal in Florida

Photo, posted August 16, 2022, courtesy of Ryan Mandelbaum via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Space Tourism And The Climate | Earth Wise

July 29, 2022 By EarthWise Leave a Comment

Space tourism is human space travel for recreational purposes. A few well-known billionaires have taken rocket rides in recent years and at least a dozen companies are at the vanguard of what they are expecting to be a burgeoning industry. If space tourism truly takes off – pun intended – it could be a serious threat to the climate and the environment.

Black carbon – essentially soot – is emitted when fossil fuels, including rocket fuels, are burned. Black carbon absorbs light from the sun and releases thermal energy, making it a powerful climate warming agent. At lower altitudes, black carbon quickly falls from the sky, remaining in the atmosphere for only a matter of days or weeks.

Rockets are another story entirely. They dump black carbon into the stratosphere as they blast into space, and up there black carbon is 500 times worse for the climate and sticks around for several years.

A detailed study by researchers at University College London looked at the climate impact of present-day space launches compared with the potential massive expansion of launches from a large space tourism industry.

The overall result is that current space launches are not a significant source of emissions, but space launches would become incredibly significant if projections of tourist space flights proved to be true. Currently, there are roughly 100 space launches a year world-wide. If that number becomes thousands, the impact on the climate would be substantial.

The same researchers looked at the ozone impact of rocket launches and reached a similar conclusion. The current impact of spaceflights is not very significant, but a massive increase in launches could have a major impact on atmospheric ozone concentrations.

Space tourism may be exciting, but it also could be very dangerous for the planet.

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Space Tourism Poses a Significant ‘Risk to the Climate’

Impact of Rocket Launch and Space Debris Air Pollutant Emissions on Stratospheric Ozone and Global Climate

Photo, posted May 30, 2020, courtesy of Daniel Oberhaus (2020) via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Methane Leaks Are Worse Than We Thought | Earth Wise

May 4, 2022 By EarthWise Leave a Comment

Methane leaking from oil and gas wells is a real problem for the environment because methane is far more potent at trapping heat than carbon dioxide. The EPA has estimated that about 1.4% of the methane produced by wells nationally leaks into the atmosphere. However, environmental experts and energy industry engineers have been concerned that leaks from mines, wells, refineries, storage facilities, and pipelines are vastly underreported. But until recently, there really wasn’t a good way to find out.

Researchers at Stanford University have developed a technique based on the use of hyperspectral cameras mounted to airplanes. The cameras measure sunlight reflected off of chemicals in the air that are invisible to the human eye. Each chemical, including methane, has a unique fingerprint. Using these sensors, methane is easy to spot and the technique can measure the output of individual wells.

The researchers performed a study of almost every oil and gas asset in the New Mexico Permian Basin, one of the largest and highest-producing oil and gas regions in the world. They surveyed the sites for an entire year. They estimate that more than 9% of all methane produced in the region is being leaked into the skies, far more than EPA estimates.

The positive outcome of the survey is that the researchers found that fewer than 4% of the 26,000 sites studied produced half of all the methane emissions observed. Being able to identify the so-called super-emitter sites and dealing with them could lead to a major improvement in the situation.

The new technique is more accurate, faster, and more cost-effective than current ways to monitor emissions.

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Stanford-led study: Methane leaks are far worse than estimates, at least in New Mexico, but there’s hope

Photo, posted July 10, 2016, courtesy of Ken Lund via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dust From The Sahara | Earth Wise

July 9, 2020 By EarthWise Leave a Comment

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.

Complications For New York Solar Farms

July 12, 2019 By EarthWise Leave a Comment

A study by engineers at Cornell University looked at the implications of adding utility-scale solar farms throughout New York State. Adding such farms could reduce demand for electricity from conventional sources by nearly 10% in some places. But the engineers caution that winters in upstate New York could create some novel problems for the state’s power system.

Electrical energy demand tends to be low around midday when many people are not home. Electrical production from solar farms is high at that time when the sun is at its highest position in the sky. This can lead to what power system operators call “ramping”, which is the term for rapid increases or decreases in demand.

This sort of ramping was first discussed in California years ago. When people wake up and prepare for the day, there is a morning peak in electrical load, which occurs before solar production ramps up. When people get home from work in the evening, energy demands create a second peak. A graph of this lack of synchronicity of load and supply looks a little like the shape of a duck and is popularly known as the duck curve.

The Cornell engineers figured out that maximum ramping in New York – where electrical demand and electricity supply from solar farms are out of synch- will take place in the winter. In fact, when there are several days of sunshine in a row during winter, the largest ramping in the New York power system will take place.

The general issue of having solar energy available when it is most needed is one that is the driver for energy storage technology. If the energy can be provided when demand calls for it, there would be no more ramping.

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Winter could pose solar farm ‘ramping’ snag for power grid

Photo, posted September 8, 2015, courtesy of New York National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Removing CO2 From The Air

July 18, 2018 By EarthWise Leave a Comment

A growing body of work is leading to the conclusion that it may be nearly impossible to prevent global temperatures from rising more than 1.5 degrees Celsius (or 2.7 degrees Fahrenheit) because we are simply not reducing emissions quickly enough. By some estimates, the current level of emissions will lock in that large a gain within the next few years. At that point, the only way to reverse the effects is to remove carbon dioxide from the atmosphere, where it otherwise will stay for hundreds to thousands of years.