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Melting Permafrost | Earth Wise

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The Arctic is warming faster than any region on Earth and mostly we’ve been hearing about the rapid disappearance of Arctic sea ice.  But the land in the Arctic is also undergoing major changes, especially to the permafrost that has been there for millennia.

Permafrost occurs in areas where the temperature of the ground remains below freezing for two years or more.  About a quarter of the Northern Hemisphere’s landscape meets this criterion.  Most of the world’s permafrost is found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

Permafrost regions previously carpeted in cranberries, blueberries, shrubs, sedges, and lichen are now being transformed into nothing but mud, silt, and peat.  So-called regressive thaw slumps – essentially landslides – are creating large craters in the landscape.  (The Batagaika Crater in the Yana River Basin of Siberia is a kilometer long and 100 meters deep).

Apart from the violence being done to the Arctic landscape, the greatest concern is that the permafrost has locked in huge stores of greenhouse gases, including methane, carbon dioxide, and nitrous oxide.  It is estimated that the permafrost contains twice as much carbon as is currently contained in the atmosphere.  As the permafrost thaws, these gases will be released.  With them will be pathogens from bygone millennia whose impact cannot be predicted.  Climatologists estimate that 40% of the permafrost could be gone by the end of the century.

As the permafrost thaws, the region’s ecosystems are changing, making it increasingly difficult for subsistence indigenous people and Arctic animals to find food.  Landslides are causing stream flows to change, lakes to suddenly drain, seashores to collapse, and water chemistry to be altered.

The warming Arctic is about much more than disappearing sea ice.

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How Thawing Permafrost Is Beginning to Transform the Arctic

Photo, posted February 9, 2017, courtesy of the U.S. Geological Survey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Narwhal Tusks And Stories Teeth Can Tell | Earth Wise

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Teeth and particularly narwhal tusks are getting some unusual press recently when one of them was the weapon of choice to fend off the London Bridge attacker, which was a good choice according to Harvard dental researcher Dr. Martin Nweeia.  Turns out that narwhal tusks have some pretty amazing physical features.  They exhibit both extreme strength and flexibility at the same time.  The narwhal is known as the unicorn of the sea, a pale-colored, medium-sized whale found in Arctic coastal waters and rivers.  In males, the more prominent tooth grows into a sword like, spiral tusk up to 8.8 feet long.

Changes in the shape of teeth over time can tell us about climate change. Adaptations in horse teeth 55 million years ago from North America were observed and caused by changes in climate, favoring different food sources.  The horses changed their diets from fruit to more favorable grasses and their teeth changed in response. For this same reason, the teeth of elephants adapting in different environments of Asia and Africa have different tooth forms.  Both eat plants but Asian elephants, with more ridges on their teeth, eat larger amounts of grasses while African elephants, with wider spread ridges, eat more leaves. 

Teeth have been used to link land mass theories like the Bering Land Strait Theory, hypothesizing that North America and Asia were once one land mass. The teeth shape and form of people on both sides of the Bering Land Bridge shared a common “mongoloid dentition” with unique features. And so, can the narwhal tusk tell us something about a changing Arctic?  Scientists have discovered that the narwhal tusk is a giant sensory organ that is able to continually monitor its environment and has the ability to detect ice formation, and melt, both capabilities helpful for surviving in a changing Arctic.

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–Earth Wise acknowledges script contribution from Dr. Martin Nweeia of Harvard University.

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Fossil teeth reveal new facts about a mass extinction 260 million years ago

From the Horse’s Mouth: Teeth Reveal Evolution

Photo, posted April 3, 2019, courtesy of James St. John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Hot November

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This past fall saw yet more of the high temperatures the world has been experiencing in recent times.  Both the season (September through November) and the year to date were the second hottest in recorded history.  November itself was the second-hottest November in the 140-year global climate record.

The high temperatures were felt at both ends of the world.  Sea ice coverage across both the Arctic and Antarctic oceans fell to near-record lows in November.  Arctic sea ice coverage was nearly 13% below the 1981-2010 average, while Antarctic coverage was 6.35% below average.

The average global land and ocean surface temperature for November was 1.66 degrees Fahrenheit above the 20th century average.  The year-to-date global temperature was 1.69 degrees Fahrenheit above the 20th century average.  These numbers correspond to almost a 1-degree Celsius increase, which should be compared with the Paris Climate Accord goal of keeping that increase to no more than 1.5 degrees.

November was the hottest November on record for South America, Africa, and the Hawaiian Islands.  The Caribbean had its second-hottest November, and Europe had its seventh hottest on record.

The world’s average sea surface temperature ranked second warmest for the year to date and was only 0.05 degrees cooler than the all-time record.

The National Oceanic and Atmospheric Administration issues monthly global climate reports and for quite some time, these reports seem to all be the same.  Another new record for heat or at least another near record.  We have to expect that this trend will continue at least until the world starts making progress in dealing with its root cause.

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November 2019 was 2nd hottest on record for the planet

Photo, posted July 20, 2016, courtesy of Salehin Chowdhury via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon Capture As Big Business

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Removing greenhouse gasses from the atmosphere is an essential part of the overall effort to achieve zero net carbon emissions and stabilize the climate.  Since we have not been able to reduce emissions fast enough to do the job, it is important to find ways to pull carbon dioxide out of the atmosphere.

There are many ways to do it, but they tend to be rather expensive and, so far, the need to mitigate climate change does not seem to provide sufficient incentive. A new study by researchers at UCLA, the University of Oxford, and five other institutions, analyzed the possibility of creating a large global industry based on capturing carbon dioxide and turning it into commercial products.

The study investigated the potential future scale and cost of 10 different ways to use carbon dioxide, including in fuels and chemicals, plastics, building materials, soil management, and forestry.  The study looked at processes using carbon dioxide captured from waste products that are produced by burning fossil fuels as well as by simply capturing it directly from the atmosphere.  The study also looked at processes that use carbon dioxide captured biologically by photosynthesis.

The conclusions of the study were that on average each of the ten utilization pathways could use about half a billion tons of carbon dioxide that would otherwise escape into the atmosphere.  Thus, theoretically, these various pathways could take more than five billion tons of CO2 out of the atmosphere.   Currently, fossil fuel combustion emits about 40 billion tons of carbon dioxide.

The authors of the study stress that there is no silver bullet in the fight against climate change.  It will require multiple approaches – including CO2 removal for industrial use – to make real progress

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Carbon dioxide capture and use could become big business

Photo, posted September 18, 2015, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas Will Erase Cities

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According to new research, climate-driven sea level rise could affect three times more people by 2050 than previously thought.  This sobering assessment means some of the world’s great coastal cities, including Bangkok, Shanghai, Mumbai, Basra, Alexandria, and Ho Chi Minh City, could be in big trouble.   

Scientists have always relied on land elevation data to determine the effects of sea level rise over large areas.  But standard elevation measurements using satellites struggle to differentiate the true ground level from the tops of trees or buildings.  The authors of the paper developed a more accurate way to calculate land elevation by using artificial intelligence to determine the error rate and to correct for it.  The new findings revealed that 150 million people – three times more than previously thought – are now living on land that is projected to be below the high-tide line by the middle of this century. 

Eight Asian nations – China, Bangladesh, India, Vietnam, Indonesia, Thailand, the Philippines, and Japan – account for about 70% of the people living on at-risk land. 

More than 20 million people in Vietnam, including much of Ho Chi Minh City, live on land that will be inundated by 2050.  In Thailand, more than 10% of its citizens, including much of Bangkok, currently live on land imperiled by projected sea level rise. 

This new research was produced by Climate Central, a New Jersey-based science organization, and was recently published in the journal Nature Communications. 

Sea level rise is clearly not just an environmental problem.  It’s a humanitarian crisis.

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New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding

Rising Seas Will Erase More Cities by 2050, New Research Shows

Photo, posted December 18, 2009, courtesy of Misko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Arctic As A Carbon Source

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According to a new NASA-funded study, the Arctic may now be a source for carbon in the atmosphere rather than being the sink for it that is has been for tens of thousands of years.

The study, published in Nature Climate Change, warns that carbon dioxide loss from the world’s permafrost regions could increase by more than 40% over the next century if human-caused greenhouse gas emissions continue at their current pace.  Worse yet, carbon emitted from thawing permafrost has not even been included in most climate models.

Permafrost is the carbon-rich frozen soil and organic matter that covers nearly a quarter of Northern Hemisphere land area, mostly in Alaska, Canada, Siberia, and Greenland.  Permafrost holds more carbon than has ever been released by humans from fossil fuel burning, but it has been safely locked away by ice for tens of thousands of years.

As global temperatures rise, the permafrost is starting to thaw and release greenhouse gases into the atmosphere.

The recent findings indicate that the loss of carbon dioxide during the winter in the Arctic may already be offsetting carbon uptake during the growing season.  The researchers compiled on-the-ground observations of carbon dioxide emissions across many sites and combined these with remote sensing data and modeling.  They estimate that the permafrost region is now losing 1.7 billion metric tons of carbon during the winter season but taking up only 1 billion during the growing season.

The major concern is that as the Arctic continues to warm, more carbon will be released into the atmosphere from the permafrost region, which will further the warming.  Climate modeling teams across the globe are trying to incorporate these findings into their projections.

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Arctic Shifts to a Carbon Source due to Winter Soil Emissions

Photo, posted July 27, 2015, courtesy of Gary Bembridge via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Plants Plump

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The leading cause of crop failures worldwide is drought.  Ironically, the very close runner-up is flooding.  Facing a changing and increasingly erratic climate, farmers need all the help they can get in protecting their crops.

Researchers at the University of California, Riverside, have created a chemical to help plants hold onto water, which could stem the tide of massive annual crop losses from drought.  Details of the team’s work is described in a paper published in Science.

The chemical is called Opabactin, but is also known as “OP.” OP is gamer slang for overpowered, referring to the best character or weapon in a game.

OP mimics abscisic acid, or ABA, which is the natural hormone produced by plants in response to drought stress.  ABA slows a plant’s growth, so it doesn’t consume more water than is available and doesn’t wilt.  OP is 10-times stronger than ABA, which makes it a super hormone.  It works fast.  Within hours, there is a measurable improvement in the amount of water plants release.  Because it works so quickly, OP could give farmers more flexibility in how they deal with drought.   Plants can’t predict the future, but if, for example, farmers think there is a reasonable chance of drought, they could make decisions such as to apply OP to improve crop yields.

The research team is now trying to find a second chemical tool.  Whereas OP slows down plant growth, the team wants to find a molecule that will accelerate it.  Such a molecule could be useful in controlled environments such as indoor greenhouses.  There are times when you want to speed up growth and times when you want to slow it down.

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Game changer: New chemical keeps plants plump

Photo, posted June 7, 2013, courtesy of Bayer CropScience UK via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The March Of The Penguins Toward Extinction

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According to a new study from the Woods Hole Oceanographic Institution, the warming climate may render emperor penguins extinct by the end of this century.  The study, which was part of an international collaboration between scientists, finds that emperor penguins will likely experience an 86% decline by 2100 if the global climate continues to warm at the current rate.  At that point, it would be very unlikely for them to recover, according to the study’s lead author.       

The research was funded by the National Science Foundation and recently published in the journal Global Change Biology.

The fate of emperor penguins is largely tied to the fate of sea ice.  The penguins use sea ice as a place for breeding, feeding, and molting.  They look for very specific conditions of sea ice – it must be locked in to the Antarctic shoreline but also close enough to open seawater to give them access to food. The study predicts that this sea ice will gradually disappear, depriving the birds of their habitat, food sources, and ability to raise their young.     

The researchers combined two existing computer models to study three different climate change scenarios.  If the average global temperature increases by only 1.5 degrees Celsius, the study found that only 5% of sea ice would be lost by 2100, resulting in a 19% drop in penguin colonies.  If the planet warms by 2 degrees Celsius, the sea ice loss nearly triples and more than a third of penguin colonies disappear.  The ‘business as usual’ scenario where the planet continues to warm at the current rate will ensure a near complete loss of emperor penguin colonies by 2100. 

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Unless warming is slowed, emperor penguins will be marching towards extinction

Photo, posted January 15, 2011, courtesy of Eli Duke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Geoengineering And Volcanoes

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Solar geoengineering is a theoretical strategy for curbing the effects of climate change by introducing aerosol particles in the upper atmosphere to reflect some of the Sun’s radiation back into space and thereby cool the planet.  It would basically be intentionally tinkering with the climate system on a global scale.

The concept is fraught with the danger of unintended consequences and most experts consider the idea almost unthinkable.  But there are those who see it as a last resort if all our other efforts to mitigate the effects of climate change are unsuccessful.

Proponents of the idea like to describe the technique as being like a human-made volcano.  Major volcanic eruptions spew ash particles into the atmosphere which can linger for as long as a few years.  The result is cooler temperatures, sometimes across much of the globe.  The Krakatoa eruption of 1883 lowered average Northern Hemisphere temperatures by more than 2 degrees and created chaotic weather patterns until about 1888.

Researchers at the Carnegie Institution and two Chinese research institutions used sophisticated modeling techniques to compare the effects on the climate of a volcanic eruption with long-term geoengineering deployment.

They found that the volcanic eruption created a greater temperature difference between the land and sea than the geoengineering and resulted in very different precipitation scenarios.  In both cases, there would be less available water for people on land.

Overall, the study demonstrated that volcanic eruptions are imperfect analogs for geoengineering and that scientists should be very cautious about extrapolating too much from them.  It is important to evaluate geoengineering from an informed position, but the truth is that it represents a great and perilous unknown.

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Geoengineering Versus A Volcano

Photo, posted November 1, 2002, courtesy of the NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bad News For The Aletsch Glacier

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The Aletsch Glacier in Switzerland is the largest glacier in the Alps.  Every year, it attracts thousands of visitors from around the world.  The huge ice flow in the Upper Valais region of Switzerland is an Alpine tourist attraction second only to the Matterhorn.  In the summer, meltwater from the glacier is an important water source in the dry Rhone Valley.

As the climate continues to warm, the massive glacier continues to shrink.  The tongue of the glacier has receded by about a kilometer since the year 2000 and scientists predict that this trend will continue over the coming years.

Detailed simulations by researchers at ETH Zurich assessed the future of the Aletsch Glacier under different scenarios related to the concentration of CO2 in the atmosphere and the resulting warming.

The best-case scenario in which global warming is limited to less than 2 degrees Celsius would result in the glacier being half the size it is today by the end of the century.  If the global community does not pull together quickly to take effective measures against global warming, Switzerland could warm by as much as 4 to 8 degrees and by 2100, what was once the largest glacier in the Alps will be a couple of measly patches of ice.

To understand how much global warming has already impacted the glacier to date, even if somehow the climate remains the same as it has been for the past 10 years going forward, the ice volume of the Aletsch glacier will still decrease by nearly half its volume by the end of the century.  The glacier is no longer in equilibrium with the climate.

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Gloomy forecast for the Aletsch Glacier

Photo, posted April 7, 2007, courtesy of Jessica Gardner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

An Upside Of Climate Change

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In contrast with most countries in the world, the main political factions in the United States have very different views of climate change.  Somehow, one side of the aisle remains skeptical about the changing climate even as temperature records are broken, arctic ice disappears, and powerful storms become increasingly common.

But putting aside the increasingly inexplicable political schism about climate change, there are instances where the consequences of the warming climate are not all dire.  In fact, there are places where climate change is having a positive effect.

One such place is West Virginia, where research studies are finding a real upside to the changing climate.

A recent study of the climate in West Virginia over the period from 1900 to 2016 found the maximum temperatures trended downward, average minimum temperatures ascended, and annual precipitation increased.  On average, West Virginians are now seeing cooler summers, warmer winters and wetter weather.

Given these changes, there have been big changes in agriculture.  Yields of important crops like hay, corn, winter wheat, and soybeans have all increased.  The winter season has shrunk by as much as 20 days and the growing season itself has increased by approximately 13 days.  A number of crops that historically did not fare well in West Virginia may now become viable.  It may even be possible to pursue double cropping, meaning that the longer growing season may allow farmers to raise one crop, harvest it, and then raise and harvest a second crop within the same year.

In the big picture, climate change is shaping up as a global calamity, but for a few people in certain places – such as West Virginia – it may have some real upside.

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The positive implications of…climate change? WVU researcher sees agricultural, food availability and economic possibilities

Photo, posted November 12, 2014, courtesy of Mike via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Maple Syrup And Climate Change

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According to a study recently published in the journal Forest Ecology and Management, scientists are predicting another casualty of climate change: the U.S. maple industry.  By the year 2100, the maple syrup season in the United States may be less productive and arrive one month earlier than it has between 1950 and 2017.

Maple syrup production is impacted by two climate-sensitive factors: sugar content and sap flow.  Sugar content is determined by the previous year’s carbohydrate stores.  Sap flow depends on the freeze/thaw cycle.  Sap begins to flow in sugar maples when winter nights dip below freezing and the days warm above freezing.

The researchers studied six sugar maple stands from Virginia to Quebec, Canada over a six year period.  They created a model that predicted the timing of optimal sap flow based on historical temperature data on freeze/thaw days, actual sap collection from their field work, and monthly climate. 

According to modeling projections, the maple syrup season is expected to be, on average, one month earlier by the end of the century.  States like Indiana and Virginia will barely produce any sap.  New Hampshire and Vermont are likely to be least affected, but are still expected to experience a decrease in production.  In fact, most areas of maple production in the United States are projected to see decreases in production by the year 2100, while areas in northern Ontario and Quebec should see moderate to large increases in production. 

Currently, Canada is responsible for approximately 80% of global maple syrup production while the U.S. produces 20%.  The shifting climate for optimal maple production will leave many scrambling to find the sweet spot. 

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Climate change study finds that maple syrup season may come earlier

Photo, posted March 24, 2019, courtesy of Paul VanDerWerf via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe Is Warming Faster Than Predicted

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A new study has found that Europe is warming faster than even climate models projected.  The number of summer days with extreme heat in Europe has tripled since the 1950s, while the number of days with extreme cold has decreased by factors of two or three depending on the region.

According to climate scientists at the Swiss Federal Institute of Technology in Zurich, the climate trends are much larger than what would come from natural variability and are a clear signal of climate change.  Extremely hot days in Europe have become hotter by an average of more than 4 degrees Fahrenheit while extremely cold days have warmed by more than 5 degrees.  The research examined data from weather stations across Europe from 1950 to 2018.  Over 90% of the stations recorded increasing temperatures over time, a percentage much too high to be purely from natural climate variability.  The results also showed that the region was warming even faster than climate models projected.

The research results come after an extremely hot summer in Europe.  Southern France hit 114.8 degrees, a new record, in June.  Germany, the Netherlands, and Belgium all recorded all-time national temperature highs.  The National Oceanic and Atmospheric Administration recently announced that July was the hottest month ever recorded.

European summers and winters will only grow hotter in the coming years as climate change accelerates.  The rapidly increasing temperatures will impact cities and people that are unprepared for them and pose real risks for residents in the coming decades.  Extreme heat is dangerous because it stresses the human body, potentially leading to heat exhaustion or heat stroke.

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Europe warming faster than expected due to climate change

Photo, posted July 30, 2011, courtesy of Marcel de Jong via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The State Of The Climate

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The federal government has issued the annual State of the Climate report and it is a sobering one.  The report states that carbon dioxide in the atmosphere rose to levels the world has not seen in at least 800,000 years.  Global carbon dioxide concentrations reached a record 407.4 parts per million during 2018.  That is 2.4 ppm more than 2017.

Other greenhouse gases like methane and nitrous oxide also continued their rapid increase.  Taken together, the global warming power of greenhouse gases was 43% stronger than it was in 1990.

Along with greenhouse gases, global sea levels also reached their highest levels on record for the seventh consecutive year.  Ocean levels are rising about an inch per decade, but that number may rise if ice melt at the poles continues to accelerate.

Global temperatures had their fourth highest level on record in 2018, slightly lagging 2016, 2015, and 2017 for the highest ever.  A La Niña over the Pacific cooled ocean waters for part of 2018, keeping temperatures a bit lower.  So far, 2019 is on track to be the warmest year in recorded history.

Global sea temperatures also set a record level in 2018.  And glaciers continued to melt at an alarming rate for the 30th consecutive year.

The State of the Climate report is yet another in a series of expert, science-based reports that continue to sound the alarm about the climate crisis.  Climate change is affecting our weather, agricultural productivity, water supply, public health and national security.  Unfortunately, the facts continue to be drowned out for many people by blogs, pundits, and posts on social media.

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Greenhouse Gases Reach Unprecedented Level

Photo, posted January 13, 2014, courtesy of Ronnie Robertson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Importance Of The Amazon Rainforest Fires

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The Amazon rainforest covers extensive parts of Brazil, Peru, Colombia, and small parts of six other countries.  It is the largest rainforest in the world and is instrumental in driving the weather and climate in South America.

The raging wildfires in the Amazon rainforest are a source of great concern.  The Amazon is always prone to wildfires during the dry season in South America, but the extent and number of fires this year cannot be attributed simply to drought.  The surge in fires has come from illegal deforestation by loggers and farmers, who are using the cleared-out land for cattle ranching.

Rainforests produce consistently high amounts of rainfall throughout the year by pulling water from the soil and then releasing it into the atmosphere.  The Amazon rainforest essentially makes it rain in South America. 

Over time, the forest plays a crucial role in cycling carbon out of the atmosphere by turning it into biomass.  The Amazon jungle sucks up as much as a quarter of the planet’s atmospheric carbon dioxide.

Pristine rainforest burns less frequently and less intensely than cleared and recovering forest.  As more and more of the Amazon rainforest is deforested, it becomes more likely to burn each year.

The major disruption of the water dynamics in South America has the potential to not only drive the weather in South American countries but even potentially influence natural resources like snow packs in the Northern Hemisphere.

The skies of Sāo Paulo, Brazil’s financial hub have been dark at midday because of the Amazon fires.  This is like having a fire in California and seeing the smoke in Boston.  The Amazon rainforest fires are a big problem for the whole world.

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The Amazon Rainforest has been burning for weeks. Here’s why that matters.

Photo, posted August 21, 2019, courtesy of NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Contrails And Climate Change

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The white wispy trails of condensation produced by the exhaust from aircraft engines have been the subject of a popular conspiracy theory for quite a while.  The story goes that the long-lasting condensation trails are actually “chemtrails” composed of chemical or biological agents left in the sky by aircraft and are intentionally sprayed for a variety of nefarious purposes undisclosed to the general public.  This story, of course, is nonsense.

But while contrails are not deliberate efforts to modify weather, control population, manipulate psychology, or any of the other bizarre things attributed to them, it turns out that they are having unfortunate effects on the climate.

It turns out that contrails are creating an often-invisible thermal blanket of cloud across the planet that has a significant effect on atmospheric temperatures.  Contrails are essentially human-made clouds that form above 25,000 feet where the air is moist and colder than -40 degrees Celsius.  At times, contrails stick around in the sky, either as tight, white lines like chalk marks, or by spreading to create thin layers of ice clouds.  At any one time, contrail-created clouds cover more than half a percent of global skies.

Research has shown that when contrails are around, nighttime temperatures can go up appreciably.  After 9/11, when all U.S. flights were grounded for three days, the difference between daytime and nighttime temperatures actually increased by about 3 degrees Fahrenheit because nights were cooler.

The effects of aviation on climate, both from the CO2 emissions from aircraft engines and from these contrail effects are becoming an increasingly important issue. To complicate matters further, as aircraft engines become more efficient, they will create more, whiter, and longer-lasting contrails.

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How Airplane Contrails Are Helping Make the Planet Warmer

Photo, posted May 15, 2012, courtesy of Mike Lewinski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Methane From Animals

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Methane emissions from ruminant livestock are currently estimated to be more than 100 million tons each year and, after rice agriculture, represent the biggest human-initiated methane source.  Given that fact, there is widespread encouragement for people to reduce their consumption of meat in order to reduce the amount of the potent greenhouse gas going into the atmosphere.

But an additional strategy to lower global methane emissions is to actually reduce the amount of methane produced by each animal.  To that end, researchers at the University of Otago in New Zealand have now identified new processes that control methane production in the stomachs of sheep and similar animals like cattle and deer.

They determined the specific microbes and enzymes that control the supply of hydrogen, which is the main energy source for methane producing microbes, known as methanogens.  Their work is focused on the development of small molecule inhibitors and vaccines to specifically target the production of methane by methanogens.  By reducing the supply of hydrogen to methanogens, it is possible to reduce animal methane emissions.

The research involved studying two types of sheep – those producing large amounts of methane and those producing less.  They found that the most active hydrogen-consuming microbes differed between the sheep.  Specifically, in the low methane emitting sheep, hydrogen consuming bacteria dominated over methanogens.

Ultimately, a strategy might emerge to introduce feed supplements that encourage non-methane producers to out-compete methanogens.  Controlling the supply of hydrogen to the methanogens will lead to reduced methane emissions. 

Having low-emission cattle would definitely help reduce the impact of agriculture on the climate.

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Scientists discover processes to lower methane emissions from animals

Photo, posted April 7, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Meeting Climate Goals With Current Energy Infrastructure

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The Paris Climate Agreement set forth a goal to keep global warming below 2 degrees Celsius as well as a more optimistic (and preferable) goal of keeping the temperature rise to less than 1.5 degrees.  Reaching either of these goals requires getting to net-zero emissions by the middle of the century.

A new paper, published in Nature, looks at the issue of whether existing power plants and other fossil-fuel-burning equipment (including vehicles) can continue to operate until they age out of functionality, or whether they need to be retired early.

The results of the study are that future emissions from existing facilities would take up the entire carbon budget needed to limit warming to 1.5 degrees Celsius and almost 2/3 of the budget needed to keep warming below 2 degrees over the next 30 years.

So, the good news is that we can still avoid a 2-degree rise without having to shut down all the existing power plants early.  But we would definitely have to stop building new things with smokestacks and tailpipes that dump CO2 into the atmosphere. 

That good news is tempered by the fact that the number of fossil fuel-burning power plants and vehicles in the world has increased dramatically over the past decade, spurred by rapid economic and industrial development in China and India.  In fact, China is predicted to produce more than 40% of all the carbon emissions over the next 30 years.

The 2-degree climate goal is not at all the most desirable result.  The 1.5-degree target would be far better for the climate.  But if the world is to achieve it, there will be dramatic changes needed in the existing infrastructure – either shutting it down or retrofitting it to drastically reduce emissions.

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Two-Degree Climate Goal Attainable Without Early Infrastructure Retirement

Photo, posted March 5, 2010, courtesy of Tennessee Valley Authority via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hottest Month Ever

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European climate researchers announced that July was the hottest July ever recorded and since July is generally the hottest month of the year, it was indeed the hottest month ever recorded.  It just barely beat out the previous record set in July 2016.  There are multiple agencies that track temperatures around the world, and it is possible that some of them may report slightly different results. 

But whatever July’s ultimate ranking is, it is part of a long-term trend.  The past five years have been the hottest on record.   The 10 hottest years ever recorded have all occurred during the past twenty years.

This June was also the warmest on record, and the previous five months were all among the four warmest for their respective months.  All of that puts this year on track to be in the top five warmest years, or perhaps the hottest ever.

The highest above-average conditions were recorded across Alaska, Greenland, and large areas of Siberia.   Large parts of Africa and Australia were warmer than normal, as was much of central Asia.  New temperature records were set in Belgium, the Netherlands, and Germany with temperatures over 104 degrees Fahrenheit.  Great Britain saw an all-time record of 101.7 degrees and Anchorage, Alaska stayed above 79 degrees for a record six days in a row.

Wildfires have raged across the Russian Arctic, India has suffered heatwaves and severe water shortages, and Japan saw more than 5,000 people seek hospital treatment during a heatwave.

While scientists cannot directly link any particular heatwave to climate change, the trend for new heat records is likely to continue and accelerate unless we do something about curbing greenhouse gas emissions.

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Web Links

How Hot Was July? Hotter Than Ever, Global Data Shows

Photo, posted May 25, 2019, courtesy of Jakob Montrasio via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Energy Demand

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Human beings are utterly dependent upon energy both for our well-being and for societal development.  Our energy use is highly dependent upon climate since so much energy is expended either keeping us warm in winter or cool in summer.  As the climate changes, it is important to understand how energy demand is likely to be affected.

A new study published in Nature Communications by researchers in Austria, Italy and the United States explored this topic.  The study is a global analysis using temperature projections from 21 climate models, and population and economy projections for five socioeconomic scenarios.  The purpose was to determine how energy demand would shift relative to today’s climate under modest and high-warming scenarios by the year 2050.

The findings indicate that, compared to scenarios in which energy demand is driven only by population and income growth, climate change will increase the global demand for energy by 11-27% by the year 2050 under a modest warming scenario.  With vigorous climate warming, energy demand would increase by 25-58%.  (Large areas of the tropics, as well as southern Europe, China, and the US are likely to experience the highest increases).

These findings are important because if energy use rises and leads to additional emissions of heat-trapping greenhouse gases, it will be increasingly difficult to mitigate future climate warming.  Quantifying this risk provides even more incentive for reducing greenhouse gas emissions before these effects upon demand are realized and it becomes even more difficult to prevent further impacts.

Policymakers need to be aware that even moderate levels of climate change will lead to increases in energy demand that will make it increasingly difficult to minimize the harmful effects on their societies.

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Web Links

More energy needed to cope with climate change

Photo, posted December 15, 2008, courtesy of Matt Hintsa 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...)