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Shrinking coal and the gas trap

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An important part of the 2015 Paris Climate Agreement is reducing the use of coal to produce electricity.  Coal is the dirtiest fuel in common use and not burning it is a way to greatly reduce emissions.  Ten years later, coal consumption around the world has decreased dramatically. 

The most convenient alternative to coal is natural gas, which is still a fossil fuel, but one that releases less carbon than coal.  As a result, around the world many countries have increasingly switched from coal to natural gas.

While the switch is a step in the right direction, it is also one that comes with an unintended consequence.  Economists at Stanford University have found that natural gas exports by countries have the effect of discouraging investments in renewable energy.  Over the long term, the result is increases in carbon emissions.  The Stanford researchers refer to this situation as ‘the gas trap’.

As a result of the gas trap, even countries that are very concerned about climate change and want to take action by abandoning the use of coal may end up reducing their investments in renewables and, ultimately, producing more emissions.

This problem comes about because replacing fossil fuels with renewables requires large investments and can take years before the renewables can fully compete with coal.  Natural gas, as a “transition fuel” gives countries time to develop renewable solutions.  But natural gas producers keep providing large amounts of their product at attractive prices so that customers buy more and more of it rather than investing in renewables.  The gas trap isn’t permanent or inevitable, but it is currently a problem.

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How the rush to quit coal is fueling a new ‘gas trap’

Photo, posted February 7, 2017, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Green transit in London

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TfL – Transport for London – the operator of the transportation system in Britain’s capital city, has signed a deal with EDF Renewables to purchase electricity from a huge solar array to be erected next year in Essex.  TfL has the goal of powering 100% of its entire transit system – including its sprawling underground railway network – with renewable electricity by 2030.

The forthcoming 1,000-acre solar facility will also transform low-quality farmland by incorporating the planting of trees and hedgerows as well as setting aside some areas for natural regeneration, attracting a greater number of species of plants and animals, expanding biodiversity in the area.  Looking after nature and protecting the environment are key elements in TfL’s contracts, in keeping with its wider goals to be greener, more sustainable, and well-adapted to climate change. 

The solar facility will generate 80 gigawatt-hours annually for the transit authority, roughly enough electricity to power 29,000 homes, comprising about 20% of its total output.  Powering the entire sprawling London underground railroad network is equivalent to powering 420,000 homes.  Over the course of the 15-year contract with EDF, TfL expects to save over 30,000 tons of carbon from its operations.

TfL plans to secure 70% of its electricity use from power purchase agreements for renewable electricity from various sources with the remainder from green tariffs.  The Mayor of London has set the goal for London to be a net zero carbon city by 2030.

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London Inches Closer to Running Transit System Entirely on Renewable Power

Photo, posted March 5, 2017, courtesy of Albert Koch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rainforests and thunderstorms

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Tropical forests are dying at an alarming rate, and not just from deforestation. Even intact forests are losing trees, threatening biodiversity, carbon storage, and the global climate. While drought and rising temperatures are often blamed, new research points to a surprising culprit: thunderstorms.

These intense, short-lived convective storms, common in the tropics, are increasing due to climate change. With strong winds and lightning, they can snap trees, strip canopies, and kill even the most robust tree specimens.

In a perspective paper recently published in the journal Ecology Letters, a research team led by the Cary Institute of Ecosystem Studies argues that thunderstorms, often overlooked in carbon storage research, may be the leading cause of tree death in tropical forests. The research team estimates that storms have caused 30 to 60% of tree mortality in the past, a number that is likely rising as storm activity increases 5 to 25% each decade.

Including storm data in forest carbon studies changes the picture significantly. Earlier models showed that carbon levels dropped sharply when temperatures rose beyond a certain point. But when storm impacts were added, that pattern disappeared, suggesting that storms – not just heat – may be a key factor in carbon loss.

Understanding which species are most vulnerable is critical for reforestation and conservation efforts. Mature trees store the most carbon, so if they’re lost to storms, future forests may fall short of their carbon storage potential.

As storm activity increases each decade, the stakes grow higher.  Accounting for storms could reshape how we protect, restore, and plan for the future of our forests. 

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Are the Amazon’s biggest trees dying? Forest coroners investigate

Photo, posted July 2, 2017, courtesy of Anna & Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The UK is heating up

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June and July have both seen multiple days with temperatures in the 90s in London, England.  This is almost unheard of, but according to British scientists, record-breaking extreme weather has become the new norm in the UK.

Weather records show that the UK’s climate is different now compared with just a few decades ago.  The number of days with temperatures 9 degrees Fahrenheit above the average from 1961-1990 has doubled in the last 10 years.  For days 14 degrees above average, the number has tripled, and for 18 degrees above average, it has quadrupled. 

Apart from the higher temperatures, rain in the UK has become more intense.  The number of months where counties receive at least double their average rainfall has risen by 50% in the past 20 years.  Sea level around the UK is rising faster than the global average, worsening the impact of coastal flooding.

An estimated 600 people died as a result of the heatwave that hit England and Wales at the end of June.  Scientists calculated that the extreme high temperatures were made 100 times more likely to have occurred as a result of climate warming.

The UK has some of the longest duration meteorological records in the world.  Those records show that recent temperatures have far exceeded any in at least 300 years.  The last three years were among the UK’s five hottest years on record. 

Today’s record-breaking temperatures are likely to be average by 2050 and positively cool by 2100, according to scientists.

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‘Profound concern’ as scientists say extreme heat ‘now the norm’ in UK

Photo, posted February 4, 2018, courtesy of Hannes Flo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geothermal energy may be safe

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The Trump Administration is outwardly hostile to renewable energy, especially solar and wind power.  Federal support for these energy sources that are by far the most rapidly growing energy sources across the globe is being gutted while fossil fuels are being propped up.

There is also renewed enthusiasm for nuclear power and, somewhat surprisingly, geothermal heat.   Geothermal is a renewable and clean energy source that has long been mostly overlooked and underfunded.  The main reasons are its expense and the fact that its large-scale use is unproven. 

Historically, geothermal energy has relied upon naturally occurring features such as hot springs and shallow underground heat sources.  However, technological breakthroughs that began in 2013 have led to enhanced geothermal systems, or EGS.  EGS makes use of the fact that if you drill deep enough into the earth pretty much anywhere, you will encounter substantial amounts of heat.  EGS plants pump water three miles down or more where it encounters rock that reaches over 500 degrees.  The piping hot water is then brought to the surface where it spins turbines to generate electricity.

Several companies are developing EGS in the U.S.  financed by tech companies seeking power for their AI activities, the Defense Department, and even by fossil fuel companies who use comparable drilling technology for fracking.

The so-called Big Beautiful Bill passed by Congress in July that eliminates tax credits for wind and solar energy preserves tax credits for geothermal projects.

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Why U.S. Geothermal May Advance, Despite Political Headwinds

Photo, posted September 30, 2019, courtesy of Stephen D Strowes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How much nanoplastic is in the oceans?

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It is unfortunately well-known that microplastics are pretty much everywhere on Earth.  They are also increasingly found in living things like birds and dolphins as well as in human brains and placentas.  The oceans are polluted with plastic, and for the first time, there is now an estimate for the volume of nanoplastics – which are even smaller than microplastics and invisible to the human eye – found in the North Atlantic.

According to a study published in the journal Nature by the microplastics and nanoplastics research group at the Helmholtz Center for Environmental Research in Germany, there are at least 30 million tons of nanoplastics in the North Atlantic, which is more than the weight of all wild land mammals on Earth.

The same researchers have analyzed plastic in lakes, urban air, and even the air in very remote places, but the new study reveals a missing part of the plastics story.

Nanoplastics are microscopic fragments smaller than one micron, about the size of small bacteria.  There has been ongoing concern about nanoplastics in ocean water, but there wasn’t the technology available to really investigate it.  While nanoplastics were expected to be found in the ocean, the sheer amount of it was surprising.

The average concentration of nanoplastics near coastlines is about 25 milligrams per cubic meter of water, about the weight of a single large bird feather.   Nanoplastics are tiny enough that they can easily infiltrate the bodies of living creatures.  For fish and other ocean animals, that means constant exposure that builds up over time.

It is highly unlikely that plastic pollution is going to stop any time soon, but there is a United Nations meeting on the subject in August in Geneva.

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Tons of Invisible Plastic Pieces Lurk in Ocean Water

Photo, posted June 24, 2020, courtesy of G.P. Schmal / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar power in Europe

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In June, solar power was the largest source of electricity in the European Union for the first time.  Solar supplied a record 22% of the power for the 27-country bloc.  At least 13 of the countries produced new monthly highs for solar power in June.  The Netherlands got more than 40% of its electricity from solar power and Greece 35%.  Other countries with record solar generation included France, Germany, and Sweden.

These solar records are for the most part a result of continuing installations of solar power in recent years as well as long stretches of hot and sunny weather.

Across the EU, nuclear power was the second largest source of electricity, followed by wind, natural gas, and hydropower.  Coal generated only 6% of the EU’s electricity, a new monthly low.  In fact, 15 countries in the EU don’t use any coal to generate electricity at all, including Austria, Belgium, and Ireland, which shut down its last coal plant in June.  All fossil fuels combined generated less than 24% of EU electricity in June, just a little more than the record low of 22.9% set in May, 2024.  Natural gas generation was somewhat higher than last year because of lower levels of hydro and wind generation.

Europe has been grappling with brutal heatwaves with triple-digit temperatures in multiple countries.  The heatwaves were, of course, accompanied by plentiful sunshine, which at least provided abundant solar power at midday, when there was the greatest demand for air conditioning.  This helped to take some of the pressure off the grid and helped to prevent blackouts.

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In a First, Solar Was Europe’s Biggest Source of Power Last Month

Photo, posted May 28, 2025, courtesy of Mike Popp via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Forest-based agroforestry

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Tree plantings have become a go-to climate solution for governments and conservation groups due to the carbon-storing potential of trees.  While planting new trees on open farmland would help capture additional carbon, a new study led by scientists from Yale School of the Environment suggests a powerful alternative: forest-based agroforestry.

Instead of clearing land for crops or starting fresh with new trees, forest-based agroforestry (or FAF) brings agriculture into existing forests.  Think fruits, nuts, and medicinal plants, for example, grown sustainably under a forest canopy – all while maintaining biodiversity and storing carbon.

According to the researchers, human activity in forests is often seen as harmful. But for thousands of years, Indigenous and local communities have managed forests in ways that actually strengthen them.

The study, which was recently published in the journal Nature Climate Change, found that FAF not only rivals tree planting in terms of climate benefits, but it can also generate income and support cultural practices tied to the land.

Despite these benefits, forest-based agroforestry receives far less funding and policy support due to two key misconceptions. It’s frequently confused with industrial systems focused on global commodity crops, and results from tropical regions are wrongly assumed to apply to temperate and boreal forests.

The researchers recommend including FAF in agroforestry policies, clearly distinguishing it from harmful industrial practices, and expanding research on FAF in temperate and boreal regions to guide better land management.

Forest-based agroforestry appears to be a natural climate solution hiding in plain sight.

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Agriculture in Forests Can Provide Climate and Economic Dividends

Photo, posted May 8, 2023, courtesy of Preston Keres / USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The world is warming and it’s happening faster

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This summer has already seen unprecedented heat in many places.  It started with a record-breaking heat dome in June in the United States.  Alaska had its first-ever heat advisory that month.  Europe has seen triple-digit temperatures in cities like Paris, Madrid, and Rome and even in places like Austria, Sarjevo, Bulgaria, Croatia, and Serbia.  On June 28th, a temperature of 96.8 degrees was measured in Biasca, Switzerland.

According to the latest report by the Intergovernmental Panel on Climate Change, the world is getting hotter, faster.  Human-caused global warming is now increasing by 0.27 degrees Celsius per decade.  That rate was recorded at 0.2 degrees in the 1970s and has been increasing ever since.

Climate scientists have long predicted that the rate of warming in the atmosphere would speed up, which has been evident from measurements for quite a while.  But now, these trends that have mostly been seen in charts and graphs are playing a growing role in people’s lives.

Each increase in the global mean temperature brings about a relatively larger increase in atmospheric extremes that include powerful downpours and severe droughts and wildfires.  According to climate models, extreme rainfall intensifies by 7% with each degree Celsius of atmospheric warming.  But recent data indicates that such record-shattering events are increasing at double that rate.

The current US administration may not accept the reality of the changing climate, but the planet really doesn’t care what it believes.

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The World Is Warming Up. And It’s Happening Faster.

Photo, posted August 28, 2013, courtesy of Tadas Balčiūnas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

AI and greener cement

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Cement pretty much holds the modern world together.  The amount of cement required to create our infrastructure is almost incomprehensible.   By weight, humanity consumes more cement than food, about 3 pounds per person per day.  The cement industry produces around eight percent of global CO2 emissions, which is more than the aviation industry.  So, if the amount of emissions produced making concrete could be reduced by even a few percent, it would make a significant impact.

Cement plants utilize rotary kilns heated to 2,500 degrees Fahrenheit to burn ground limestone down to a substance called clinker.  That energy-intensive combustion process emits large amounts of carbon dioxide.  However, the combustion process accounts for much less than half of the emissions associated with making concrete.  The majority comes from the raw materials needed to produce clinker.

One strategy to reduce concrete emissions is to modify the cement recipe itself, replacing some of the clinker with alternative materials.  Some producers already make use of materials like slag from iron production and fly ash from coal-fired power plants.   

A team of researchers at the Paul Scherrer Institute in Switzerland is making use of machine learning to simulate and optimize cement formulations that would emit significantly less CO2 while maintaining the same high level of mechanical performance.  This AI-based approach eliminates time-consuming experiments and conventional complex simulations.

The Scherrer Institute seeks to discover new materials and the effort has already yielded some promising candidates.  The next steps will be testing some of these recipes in the laboratory. 

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AI paves the way towards green cement

Photo, posted July 3, 2007, courtesy of Tim Shortt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Raccoons in Europe

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Tens of thousands of raccoons live in Kassel, a city of 200,000 people in central Germany known for its art scene.  Overall, there are an estimated 1.5 million raccoons in Germany.  The omnivorous mammals are native to North America, but they were brought to Germany in the 1930s for fur farming.  Fur farming ultimately ceased but escaping animals and intentional releases ultimately led to a large wild population of raccoons in the years afterward.

Raccoons have gradually made their way across Europe with animals spotted in France, Denmark, Poland, Italy, Austria, and elsewhere.

The people of Kassel have embraced raccoons.  In fact, the place is often called the raccoon city.  Several sports teams are named after the animals.  Many people feed them, and they are pretty much everywhere.  On the other hand, residents have to lock up their trash receptacles and they have to check under their cars before driving places.

Since 2016, the EU has classified racoons as an invasive species because of the threat they pose to native wildlife.  There are no equivalent species like them in Europe.  So, they are a threat to ground-nesting birds, bats in caves, amphibians, and more.  They are able to eat almost anything. 

What to do about raccoons in Europe is unclear.  Despite their popularity in Germany, 200,000 raccoons were culled last year.  But raccoon supporters argue that minks, which are native to Europe, and especially cats, are responsible for much of the pressure on species racoons are accused of consuming.  Meanwhile, Kassel citizens continue to enjoy their raccoons.

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Rampaging raccoons: how the American mammals took over a German city – and are heading across Europe

Photo, posted December 20, 2016, courtesy of Big Cypress National Preserve via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Deconstructing buildings

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An estimated 30 million tons of wood waste from construction and demolition in the U.S. ends up in landfills each year.  A growing number of cities have launched initiatives to reuse the wood instead.  It is a strategy to reduce carbon emissions, cut waste, and shift towards a circular economy.

For a long time, salvaged wood was a niche pursuit by people who valued the fine grain and enduring quality of older wood.  Reclaimed old-growth lumber offers character and strength.  These people pursued construction that uses wood with a story – timber recovered from historic structures, collapsing barns, and other demolished buildings.

Now, there are multiple companies in the business of salvaging wood from buildings.  Cities and businesses are embracing the use of reclaimed materials.   Ordinances in cities like Portland, Oregon, Boulder, Colorado, and San Antonio, Texas require older buildings to be taken apart for repurposing their materials.  Palo Alto, California has banned demolition completely. 

Portland was the first U.S. city to require old residential homes to be deconstructed.  After a decade, contractors have deconstructed more than 650 homes in the city, salvaging 2,000 tons of reusable wood.

Using reclaimed wood in local buildings stores carbon and reduces emissions by avoiding the need to cut new trees, process materials, and ship them long distances.

Deconstructing buildings is not a widely available skill.  Contractors have to be trained on how to dismantle buildings piece by piece.  But there is now a national registry of deconstruction trainers and a network of practitioners.

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Deconstructing Buildings: The Quest for New Life for Old Wood

Photo, posted May 16, 2018, courtesy of Alexandre Prevot via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biochar and poultry farm pollution

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Poultry farms are a significant source of air and water pollution.  In the US, they are the largest source of ammonia emissions, followed by dairy and non-dairy cattle farms. Poultry farms emit over two million tons of ammonia per year. Ammonia is not directly produced or excreted by the birds but is a common by-product of poultry wastes.

Poultry manure is a rich source of phosphate and large amounts of it are used in agricultural land as an organic fertilizer.  This poses an environmental risk when phosphates are washed into rivers and streams by rainwater. Phosphates lead to the proliferation of algae, harming other aquatic life and resulting in toxic conditions.

Researchers at the UK Centre for Ecology & Hydrology are investigating the use of biochar as a means of reducing air and water pollution from poultry farms in the UK.  Biochar is produced by heating biomass – typically wood – to high temperatures in the absence of oxygen.  The resultant material is effective at absorbing nutrients and other substances.

In laboratory experiments, adding biochar to birds’ bedding has been shown to reduce ammonia emissions from droppings by 58%.  The biochar binds ammonium to its surface, preventing release into the atmosphere as ammonia gas.

Modified biochars are also proven to be highly efficient at adsorbing phosphorous.  Adding a cost-effective biochar to poultry manure fertilizer could support the safe use of an important and otherwise renewable fertilizer.  The biochar binds phosphates in the manure to its surface, preventing leaching and run-off into waterways.

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Biochar could help restore River Wye

Photo, posted May 15, 2023, courtesy of Ark. Agricultural Experiment Station via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More efficient cooling for data centers

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Increasing reliance on digital technologies in general and artificial intelligence in particular are dramatically increasing the energy consumption of data centers.  Data centers consume far more energy per square foot than other commercial buildings.  By the year 2030, data center energy consumption in the US is projected to reach 9% of the country’s electricity generation. 

Computing hardware consumes large amounts of energy and generates large amounts of heat in the process.  Currently, cooling the equipment so it doesn’t burn out accounts for as much as 40% of a data center’s total energy use. 

Engineers at the University of California San Diego have developed a new cooling technology that could significantly improve the energy efficiency of data centers.  The technology makes use of a specially engineered fiber membrane that passively removes heat through evaporation.

The membrane has a network of tiny, interconnected pores that draw cooling liquid across the membrane surface using capillary action.  As the liquid evaporates, it removes heat from the electronics underneath.  No extra energy is required.

Tests of the membrane demonstrated record-breaking performance in removing heat from electronics and being able to withstand very high levels of heat flux.

The researchers say that the technology is still operating well below its theoretical limit, and with additional work, can lead to optimized performance.  The membranes will be integrated into cold plates, which are components that attach to power-hungry computing components to dissipate heat.  The team is also launching a startup company to commercialize the new cooling technology.

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New Cooling Tech Could Curb Data Centers’ Rising Energy Demands

Photo, posted January 23, 2023, courtesy of Jefferson Lab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Marine heatwaves are spreading

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Sea surface temperatures broke records in 2024 and a quarter of the world’s oceans are experiencing temperatures that qualify as a marine heatwave.  A marine heatwave is a prolonged period during which ocean temperatures are significantly warmer than average for that specific location and time of year. 

Unusual heatwaves have occurred in all the major ocean basins around the planet in recent years and some have become so intense that they are being called super marine heatwaves.

The seas off the coasts of the UK and Ireland experienced an unusually intense and long-lasting marine heatwave starting in April.  Australia was recently struck by heatwaves on two coasts.

Hotter oceans are causing drastic changes to marine life, sea levels, and weather patterns.  Some of the most apparent casualties of ocean warming have been coral reefs.  About 84% of reefs worldwide experienced bleaching-level heat stress at some point between January 2023 and March 2025.

Excess heat in the oceans can affect weather patterns, making hurricanes more likely to rapidly intensify and become more destructive.

A recent study published in Proceedings of the National Academy of Sciences concluded that climate change has been responsible for the overwhelming majority of marine heatwaves in recent decades.

People are learning to forecast these events.  Eventually, parts of the ocean might enter a constant state of marine heatwave, at least by how it is defined today.  Studying what is going on in the oceans today may provide insights into the future of the world’s oceans and provide guidance on how to try to achieve different outcomes.

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See How Marine Heat Waves Are Spreading Across the Globe

Photo, posted December 5, 2015, courtesy of Susanne Nilsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A recycling lottery

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Getting people to recycle isn’t always easy.  The bottled beverages we buy at the supermarket often require a small deposit that we can get back by recycling the bottle, but often, we just don’t.

Researchers from the University of British Columbia tested the idea of giving people returning bottles a small chance of winning a big cash prize instead of a 10-cent deposit return.  The result was that people recycled 47% more bottles.

Changing how we reward recycling made a big difference.  When given a choice between a guaranteed return and a possible large reward, many chose the lottery option.  When people were randomly assigned to one type of reward or the other, those in the lottery group brought in almost three bottles for every two returned by the other group.

This isn’t a new idea.  Norway has a recycling lottery, and their bottle return rate is close to 100 percent.  The way it works there is there are reverse vending machines in grocery stores all over the country.  The revenues generated by the machines is split in four ways:  34.5% of the gross revenue goes to the Red Cross; 35% goes to the people who bring in their bottles in the form of winnings in the lottery; 9.75% goes to the stores for managing the machines and the lottery; and 10.75% goes to the operating company of the Recycling Lottery.

The Canadian experiments demonstrate that a recycling lottery could be effective in more places than Norway.  However, it shouldn’t completely replace the guaranteed refund option, since some people depend on it for income.

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How lottery-style bottle returns could transform recycling

Photo, posted July 9, 2011, courtesy of Mr.TinMD via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wasting less wastewater

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Ultra-pure water is essential for multiple industries, for example semiconductors, batteries, and pharmaceuticals, as well as food and beverage companies.  Such water is produced by various processes including desalination plants that use reverse osmosis.  The byproduct of the processing is industrial brine:  salty wastewater.

The brine produced by desalination is generally dumped into the ocean if the desalination plant is located at the seashore, but if the plant is inland, such as in places like Arizona, that isn’t an option.

Nestle runs a water desalinating plant near Phoenix that generates more than 50,000 gallons of brine every day.  Concentrated brines must be carefully managed and disposed of. 

Researchers at Arizona State University are developing a mobile, closed-loop water recovery demonstration system that aims to recover 50%-90% of previously unusable water from industrial brine and reduce the remainder to solid salt. 

The team’s approach involves pretreating Nestle’s brine to remove larger particles.  It then goes through a reverse osmosis process that results in a stream of high-quality water and a salty concentrate.  The salty concentrate goes through a special membrane that recovers even more pure water.  The highly concentrated brine is then dried and crystalized into a solid salt product.  Atmospheric water harvesters capture any remaining water vapor during the drying process.

In places like Arizona where freshwater is a scarce commodity, finding sustainable ways to separate water from salt is both a scientific challenge and an economic necessity.

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Squeezing every last drop out of wastewater

Photo courtesy of the Global Center for Water Technology.

Earth Wise is a production of WAMC Northeast Public Radio

Planting trees to cool the planet

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Planting lots of trees is one of many strategies being pursued to combat climate change. Forests absorb carbon dioxide, provide shade, and help regulate temperatures. They also support biodiversity and improve air and water quality.

According to a new study by researchers from the University of California – Riverside, restoring forests to their pre-industrial extent could reduce global average temperatures by 0.34 degrees Celsius. That’s equivalent to about 25% of the warming the Earth has already experienced.

The study models restoring 4.6 million square miles of forest.  While previous studies have focused on the role trees play in removing carbon, this research adds that trees also alter atmospheric chemistry in ways that boost their cooling impact.

Trees release natural chemicals called BVOCs – biogenic volatile organic compounds – which interact in the atmosphere to form particles that reflect sunlight and promote cloud formation. These effects enhance the cooling impact of forests, especially in climate models that take these chemical reactions into account.

But not all reforestation is created equal. The benefits of reforestation vary by region, with tropical forests offering stronger cooling and fewer drawbacks.  Importantly, the researchers emphasize that meaningful climate benefits don’t require restoring every lost forest. Small, localized efforts can still shift regional climates.

While forest restoration can meaningfully aid climate efforts, the researchers stress that it must complement – not replace – fossil fuel reductions.

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Does planting trees really help cool the planet?

Photo, posted May 20, 2005, courtesy of Ben Britten via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hidden hydrogen

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The idea of using hydrogen as a fuel or an energy source has been around for a long time.  Hydrogen is the most common element in the universe, but most of it is locked up in various chemical compounds, such as water.  Hydrogen is a clean fuel; burning it or using it to generate electricity in a fuel cell produces no greenhouse gas emissions.  But more than 99% of the hydrogen that people current produce is obtained by methods that result in greenhouse gas emissions.

A new study by scientists at the University of Oxford, the University of Durham in the UK, and the University of Toronto looks at geological environments in which naturally occurring hydrogen could be hiding.  According to the study, over the last billion years, the Earth’s continental crust is likely to have produced enough hydrogen to satisfy the energy needs of modern society for 170,000 years.

Much of that hydrogen is likely to have been lost or is inaccessible; most of it is not economically feasible to extract.  But even the relatively small amount of hydrogen left could provide thousands of years of energy for us.  We just have to be able to find it.

The researchers have developed what they call an “exploration recipe” which identifies where natural hydrogen might be located as well as where it could be commercially feasible to extract.  These places with hydrogen have so-called reservoir rocks and geologic formations that prevent the gas from leaking into the atmosphere.

A few such places have already been identified such as one in Albania.  There are various candidates to explore, even including an area in Kansas.  The study’s authors have founded a company whose mission is to find these natural sources of hydrogen.

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Scientists Say Hidden Hydrogen Could Power the World for 170,000 Years

Photo, posted October 4, 2019, courtesy of Tony Sprezzatura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate change and hunger

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Worldwide, people are producing more food than ever, but most of that production is concentrated into only a handful of places.  For example, fully one third of the world’s wheat and barley exports come from Ukraine and Russia.  Across the globe, several major crop-growing regions, including some in the United States, are heading towards sharp drops in harvests as a result of climate change.

These forthcoming changes are not only bad news for farmers, but they are also bad news for everyone who eats.  According to a new study published in the journal Nature, it is going to become harder and more expensive to feed a more crowded and hungrier world.

Specifically, under a moderate greenhouse gas emissions scenario, six key staple crops will see an 11.2% decline by the end of the century, compared to a world without warming.  The largest drops won’t be in the poorer, more marginal farmlands, but rather in places that are major food producers.  These are places like the US Midwest that has long benefited by having both good soil and ideal weather for raising crops like corn and soy.

When the weather is not ideal, it can drastically reduce agricultural productivity.  Extreme weather in many places has already damaged crops.  Flooding has destroyed rice in Tajikistan, cucumbers in Spain, and bananas in Australia.  Severe storms in the US this spring caused millions of dollars’ worth of damage to crops.

As the climate changes, rising average temperatures and changing rainfall patterns are likely to diminish yields and extreme weather events like droughts and floods could wipe out harvests more often.  As climate change intensifies, agriculture is the most weather-affected sector of the economy.

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How climate change will worsen hunger

Photo, posted may 20, 2011, courtesy of Lance Cheung / USDA 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...)