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Carbon In The Congo Peatlands | Earth Wise

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The Congo peatlands in central Africa are the world’s largest tropical peatlands complex, occupying an area of 65,000 square miles, about the size of the entire state of Florida. Peatlands represent a huge store of carbon and therefore are important to the stability of the climate.

A study by scientists at the University of Leeds and University College London found that around the time that Stonehenge was built – about 5,000 years ago – there was an extended drying period in central Congo and the peatlands started emitting carbon dioxide rather than storing it.  Over the course of time, the climate in the area got wetter again and over the past 2,000 years, the Congo peatlands have been a place that takes large amounts of carbon out of the atmosphere.

The study utilized peat samples taken from beneath remote swamp forests to build a record of the vegetation and rainfall in the central Congo Basin over the past 17,500 years.

In a paper published in Nature, the researchers warn that if modern-day global warming produces extended droughts in the Congo region, history could repeat itself and the peatlands could once again become carbon emitters.  If that were to happen, over 30 billion tons of carbon could be released into the atmosphere.  That is the equivalent to the total global emissions from fossil fuel burning over a three-year period.

There is some evidence that dry seasons are lengthening in the Congo Basin, but it is unknown if these will continue.  In any case, the study reveals that peatlands are more vulnerable than previously thought and need to be protected.  They are some of the most wildlife and carbon-rich ecosystems on Earth.

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Congo peatlands could release billions of tonnes of carbon

Photo, posted November 5, 2016, courtesy of Roni Ziade / Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Perennial Rice | Earth Wise

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People have been cultivating rice for more than 9,000 years.  Cultivated rice is an annual crop which is often extended to two crops a year by a process called ratooning, which is cutting back annual rice to obtain a second, weaker harvest.

An extensive project involving multiple institutions in China, the U.S., and Australia has been developing perennial rice.  The researchers developed it through hybridization, crossing a type of Asian domesticated annual rice with a wild perennial rice from Africa.  Using modern genetic tools to identify candidate plants, the team identified a promising hybrid in 2007, planted large-scale field experiments in 2016, and released the first commercial perennial rice variety, called PR23, in 2018.

The researchers spent five years studying the performance of the perennial rice alongside annual rice on farms in China’s Yunnan Province.  For the most part, the yield of the perennial rice was equivalent to that of annual rice over a period of four years. 

Because farmers don’t have to plant rice each season, growing perennial rice requires almost 60% less labor and saves nearly half the costs of seed, fertilizer, and other inputs.

Perennial rice is already changing the lives of more than 55,000 smallholder farmers in southern China and Uganda.  The economic benefits vary by location, but overall profit increases ranged from 17% to 161% over annual rice.

There are already three perennial rice varieties available to farmers, but researchers aren’t done refining the crop.  They plan to use their methodology to enhance traits such as aroma, disease resistance, and drought tolerance to newer versions.

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Farmers in China, Uganda move to high-yielding, cost-saving perennial rice

Photo, posted February 25, 2002, courtesy of Matthieu Lelievre via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Carbon Inequality | Earth Wise

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Everyone contributes to climate change through the generation of greenhouse gas emissions, but individual contributions vary greatly.   A study at the Paris School of Economics has determined that just 1 percent of the population is responsible for nearly a quarter of global carbon emissions growth since 1990.

The study estimated emissions from individuals’ consumption and their financial investments, and also from government spending in their country.  Individuals are responsible for carbon emissions as a result of their own activities, but they also bear their share of responsibility for the emissions of the firms that they own or invest in. 

In 2019, people living in sub-Saharan Africa produced an average of 1.8 tons of CO2 equivalent per capita.  In North America, the average per capita was more than 10 times higher.  Meanwhile, the top 10% of North America’s emitters produced more than 75 tons each.

From 1990 to 2019, the bottom 50% of emitters was responsible for just 16% of emissions growth, while the top 1% was responsible for 23%.  The top 0.1% saw emissions growth of 80%.

The inequality between rich and poor is driven more by inequality within countries than by inequality between countries.  This is particularly true for wealthy countries.  For example, over the study period, the top 1% saw their emissions grow by 26% while emissions actually declined 5-15% among low and middle earners even in wealthy nations.

Economic inequality drives a lot of the dynamics taking place within many countries around the world, and this even applies to pollution and greenhouse gas emissions.

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Global carbon inequality over 1990–2019

Photo, posted December 11, 2017, courtesy of Bernal Saborio via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving Lives With Air Conditioning | Earth Wise

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This summer, extreme heatwaves struck the United States, Europe, and Africa.  Thousands of people died as a result.  In July, the impact of extreme heat in places ill-prepared for it was evident.  In the U.K., where air conditioning is uncommon, public transportation shut down, schools and offices closed, and hospitals cancelled non-emergency procedures.

Air conditioning, which we mostly take for granted in this country, is a life-saving tool during extreme heat waves.  However, only about 8% of the 2.8 billion people living in the hottest – and often poorest – parts of the world have AC in their homes.

A new study at Harvard modeled the future demand for air conditioning as the number of days with extreme heat continues to increase across the globe.  The researchers identified a massive gap between current AC capacity and what will be needed by 2050 to save lives, particularly in low-income and developing countries.

If the rate of greenhouse gas emissions continues on its present course, the study concluded that that at least 70% of the population in several countries will require air conditioning by 2050.  The number will be even higher in equatorial countries like India and Indonesia.  At this point, even if the goals of the Paris Climate Accords are met, an average of 40-50% of the population in many of the world’s warmest countries will still require AC.

The research looked at various scenarios.  One in which emissions continue to increase leads to widespread need for air conditioning even in temperate countries.  In Germany, 92% of the population would need it, and here in the U.S., 96% would need it.

Planning for future power systems must take into account the essential needs of a warming world.

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In a hotter world, air conditioning isn’t a luxury, it’s a lifesaver

Photo, posted July 24, 2021, courtesy of Phyxter Home Services via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

River Of Dust | Earth Wise               

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Every year, more than 100 million tons of dust blow out of North Africa.  Strong seasonal winds lift the dust from the Sahara Desert northward.  A few times a year, the winds from the south are strong and persistent enough to drive the dust all the way to Europe.

On March 15, a large plume of Saharan dust blew out of North Africa and crossed the Mediterranean into Western Europe.  European cities were blanketed with the dust, degrading their air quality, and turning skies orange.  Alpine ski slopes were stained with the dust.

These dust events are associated with so-called atmospheric rivers that arise from storms.  Such rivers usually bring extreme moisture but can also carry dust.  Over the past 40 years, nearly 80% of atmospheric rivers over northwestern Africa have led to extreme dust events over Europe.  The March 15 event was associated with Storm Celia, a powerful system that brought strong winds, rain, sleet, hail, and snow to the Canary Islands.

Atmospheric dust plays a major role in climate and biological systems.  The dust absorbs and reflects solar energy and also fertilizes ocean ecosystems with iron and other minerals.

The climate effects of dust are complicated.  Dust can decrease the amount of sunlight reaching the surface, affect cloud formation, and decrease temperatures.  But dust also darkens the snowpack, leading to more rapid snowmelt.  A 2021 dust event resulted in a rapid melt of Alpine snow, reducing its depth by half in less than a month.

The effects of this year’s dust event are not yet known, but this atmospheric river associated with Storm Celia appeared to carry less water and more dust compared with the 2021 event.

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An Atmospheric River of Dust

Photo, posted December 2, 2019, courtesy of Catherine Poh Huay Tan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Hot Year With Record GHG Levels | Earth Wise

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Last year was a year that saw rising temperatures and rising levels of greenhouse gases.  2021 was the fifth-hottest year on record.  The average global temperature was nearly 1.2 degrees Celsius or 2.1 Fahrenheit degrees higher than the preindustrial average.  The past seven years were the hottest ever by a significant margin.

The concentration of carbon dioxide in the atmosphere reached 414 parts per million, compared with preindustrial levels of 280 parts per million.  Concentrations of methane reached 1876 parts per billion, the highest levels ever recorded. 

Apart from these global measurements, local and regional weather saw the effects of the heating planet.  Extreme temperatures were common with the hottest summer in Europe, heatwaves in the Mediterranean, and unprecedented high temperatures in North America.

The West Coast of the US, northeast Canada, Greenland, and parts of north Africa and the Middle East all experienced the highest above-average temperatures.  However, some places, including Australia, Antarctica, Siberia, and much of the Pacific Ocean often saw below-average temperatures, even though the same places occasionally experienced record high temperatures.

The Covid-19 pandemic and its economic disruptions continued to lead to some reductions in greenhouse gas emissions, but in the US, emissions from energy use and industry nonetheless grew 6.2% in 2021 after falling more than 10% in 2020.

Carbon dioxide and methane concentrations are continuing to increase each year and don’t appear to be slowing down.  As long as this situation persists, global temperatures will continue to rise, and extreme and erratic weather will be more and more commonplace.

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2021 Rated One of the Hottest Years Ever as CO2 Levels Hit Record High

Photo, posted November 11, 2011, courtesy of NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Roads And Chimpanzees | Earth Wise

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The chimpanzee is a species of great ape native to tropical regions of Central and West Africa.  Chimpanzees are highly social animals and can live to be over 50 years old.  In fact, chimpanzees are our closest cousins.  We share about 98% of our genes with chimpanzees. 

According to the African Wildlife Federation, it’s estimated that at most only 300,000 chimpanzees remain in the wild today.  They face a myriad of challenges, including habitat degradation and hunting. 

According to new research from the University of Exeter in the U.K., roads have a negative impact on chimpanzee populations that can extend for several miles.  In the study, which was recently published in the journal Conservation Letters, the researchers analyzed the impact of major and minor roads on wild western chimpanzee numbers in the eight African countries in which they live.  They found that negative impacts extended an average of 10.7 miles from major roads, and 3.4 miles from minor roads.  The researchers found that the density of chimpanzee populations dropped steadily from the edges of these areas to the lowest value alongside the roads.  Only 4.3% of the chimpanzees’ range remains unaffected by roads. 

While the study did not investigate why roads affect chimpanzee numbers, the research team did offer some clues.  In addition to noise and roadkill, roads provide access to unexploited areas for industries that often reduce or remove chimpanzee habitats.  Roads can also restrict chimpanzee movements, and provide easier access for hunters. 

The researchers hope their findings will bring about more effective guidelines to mitigate the impact of roads on wildlife.   

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Roads have far-reaching impact on chimpanzees

Photo, posted August 12, 2014, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Light Pollution

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Light pollution is excessive or obtrusive artificial light. It’s a consequence of industrial civilization.  Too much artificial light can cause a host of problems, including disrupting ecosystems, causing adverse health effects, and wasting energy. 

According to a new study led by researchers from the University of Exeter in the U.K., global light pollution has increased by at least 49% over 25 years.  But this figure only includes light visible via satellites.  Scientists estimate that the true increase may be significantly higher – up to 270% more globally. 

That’s because there is a hidden impact of LED technology that isn’t accounted for in the satellite data. LEDs emit more blue light than previous lighting technologies, but satellite sensors fail to pick up this blue light.   This leads to a large underestimate of global light pollution.

The researchers examined light pollution from 1992 to 2017.  They found persistently increasing light pollution in Asia, South America, Oceania and Africa.  In Europe, detected light increased until around 2010, after which it leveled off.  In North America, artificial light appears to be on the decline.  However, the researchers point out that the satellites inability to detect blue light of LEDs means that light pollution has likely actually increased in most locations.

Light pollution has widespread impacts on both animals and plants.  For example, light pollution can confuse the migratory patterns of animals and change predator-prey relationships.   It’s also been shown to cause trees to bud earlier in spring.      

While there’s no off switch for the planet, there are ways that we could reduce the amount of light drastically with little impact on our lives. 

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Rapid increase in global light pollution

Photo, posted November 2, 2008, courtesy of Timothy Tsui via Flickr.

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July Was A Scorcher | Earth Wise

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July 2021 has the unfortunate distinction as being the world’s hottest month ever recorded according to global data from the National Oceanic and Atmospheric Administration.   July is typically the warmest month of the year, but this July was the warmest month of any year on record.

The combined global land and ocean surface temperature was 62.07 degrees Fahrenheit, which is 1.67 degrees above the 20th century average.  This was the highest monthly average since records began 142 years ago.  It broke the previous record set in July 2016 and tied in 2019 and 2020.

The Northern Hemisphere was 2.77 degrees above average.  Asia had its hottest July on record.  Europe had its second hottest July on record.  Places like Africa, Australia, and New Zealand all had top-ten warmest Julys.

Other aspects of the changing climate included the observation that Arctic sea ice coverage for July was the fourth-smallest in the 43-year record.  Interestingly, Antarctic sea ice extent was actually above average in July.  Global tropic cyclone activity this year so far is above normal for the number of named storms.  In the Atlantic basin, the formation of the storm Elsa on July 1 was the earliest date for a 5th named storm.

It remains very likely that 2021 will rank among the 10 hottest years on record.  Extreme heat is a reflection on the long-term climate changes that were outlined recently in a major report released by the Intergovernmental Panel on Climate Change.  These latest global observations add to the disturbing and disruptive path that the changing climate has set for the world.

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It’s official: July was Earth’s hottest month on record

Photo, posted July 15, 2021, courtesy of Lori Iverson/National Interagency Fire Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The World’s Largest Harmful Algal Bloom | Earth Wise

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Brown sargassum seaweed floats in surface water in a bloom that stretches all the way from West Africa to the Gulf of Mexico.  Sargassum provides habitat for turtles, crabs, fish, and birds.

The stuff carpets beaches along the tropical Atlantic, the Caribbean Sea, the Gulf of Mexico, and the east coast of Florida disrupting tourism.  Florida’s Miami-Dade County alone spends $45 million a year cleaning up sargassum.  Annual Caribbean clean-up is in excess of $120 million.

A study by Florida Atlantic University has discovered dramatic changes in the chemistry and composition of sargassum which has transformed the so-called Great Atlantic Sargassum Belt into a toxic dead zone.

The findings of the study suggest that increased nitrogen availability from both natural and human-generated sources, including sewage, is supporting blooms of sargassum and turning a critical marine nursery habitat into harmful algal blooms with catastrophic impacts on coastal ecosystems, economies, and human health.

The study found that today’s sargassum tissues compared with those of the 1980s have 35% more nitrogen content and 42% less phosphorus.  Much of the nitrogen increase is a result of agricultural and industrial runoff from the Congo, Amazon, and Mississippi Rivers. 

The fact that the bloom itself has expanded so tremendously was already suspected to be the result of significant changes in the ocean’s chemistry.  Given the negative effect that the Great Atlantic Sargassum Belt is having on the coastal communities, additional research is essential to guide mitigation and adaptation efforts.

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Sargassum now world’s largest harmful algal bloom due to nitrogen

Photo, posted June 5, 2016, courtesy of J Brew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Promising Malaria Vaccine | Earth Wise

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Malaria is a parasitic disease transmitted through the bite of female Anopheles mosquitoes.  Although the disease is both preventable and treatable, an estimated 435,000 people die of it each year, with the majority being children younger than five.  Over 90% of all malaria cases and deaths occur in Africa.

The battle against malaria has mostly centered around the use of bed nets, insecticide spraying and antimalarial drugs.  To date, there has not been an effective malaria vaccine available.

That may finally be changing.  The first vaccinations have begun in Mali in a phase III trial of a malaria vaccine developed by the University of Oxford.  The Oxford vaccine showed an efficacy of 77% over 12 months in a phase IIb trial and the hope is that the phase III trial will lead to the licensing of the vaccine in 2023. 

Oxford is partnering with the Serum Institute of India for the manufacturing of the vaccine in order to be able to produce high volumes of low-cost vaccine and provide access to countries where it is required the most.  The Serum Institute has committed to the production of more than 200 million doses per year once the vaccine is licensed for use, which will be an adequate supply for children most at risk of malaria in sub-Saharan Africa.

The World Health Organization Malaria Vaccine Technology Roadmap has a goal of a malaria vaccine with at least 75% efficacy.  Such a vaccine is needed in order to reach the WHO’s goal of reducing malaria deaths by at least 90% by 2030.

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Promising malaria vaccine enters final stage of clinical testing in West Africa

Photo, posted June 9, 2018, courtesy of Mario Yordanov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Nitrous Oxide Is No Laughing Matter | Earth Wise

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Carbon dioxide is the most well-known of greenhouse gases.  But there are others deserving of their own spotlight.  Nitrous oxide is one of them.  It turns out that the same “laughing gas” once used by dentists as an anesthetic is pretty bad for the environment.  In fact, it’s more than 300 times more potent as a greenhouse gas than carbon dioxide, and it can remain in the atmosphere for more than 100 years.

According to a new study by a team of international scientists, rising nitrous oxide emissions around the world are jeopardizing the climate goals of the Paris Agreement.  The growing use of nitrogen fertilizers in global food production is increasing atmospheric concentrations of nitrous oxide.

The study, which was led by Auburn University and recently published in the journal Nature, finds that nitrous oxide emissions are increasing faster than any emission scenario developed by the Intergovernmental Panel on Climate Change.  The current trajectory would lead to global mean temperature increases well above 3°C from pre-industrial levels.  The Paris Agreement aims to limit global warming to less than 2°C.    

According to the study, nitrous oxide levels have risen 20% from pre-industrial levels, with the fastest growth observed in the last 50 years due to emissions from human activities.  The largest contributors to nitrous oxide emissions come from East Asia, South Asia, South America, and Africa.  The United States, China, and India dominate nitrous oxide emissions from synthetic fertilizers, while Africa and South America dominate releases of nitrous oxide from natural sources, like livestock manure. 

Nitrous oxide emissions pose an increasing threat to the climate.  

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Nitrous oxide emissions pose an increasing climate threat, study finds

Photo, posted April 22, 2012, courtesy of Bill Meier via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Decline In Wildlife | Earth Wise

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According to a new report released by the World Wildlife Fund, global populations of mammals, birds, amphibians, reptiles, and fish have declined by 68% in less than half a century. 

The report presents a comprehensive overview of the state of the natural world based on the tracking of almost 21,000 populations of more than 4,000 vertebrate species between 1970 and 2016. 

The report shows that the main cause of the dramatic decline in species populations on land is habitat loss and degradation, which includes deforestation driven by food production.  Additional factors include land-use change and the use and trade of wildlife.

Wildlife populations found in freshwater habitats have suffered a decline of 84%, which is the steepest decline in any biome.

Insect populations have declined rapidly in many places, but most of the information about insects comes from a small number of countries in the northern hemisphere.  There is very little information from large parts of the world, such as Africa, South America, and Asia, where land-use change and agricultural expansion are happening fast.  What happens to insects matters a lot to humanity.  Insects play central roles in the world’s ecosystems as waste processors, pollinators, predators, and prey. 

The report is clear evidence of the damage human activity is doing to the natural world.  Threats to the integrity of ecosystems endanger humans and all of nature.  This is especially apparent in the midst of a global pandemic.  It is now more important than ever to take coordinated global action to halt and reverse the loss of biodiversity and wildlife populations across the globe.

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Living Planet Report reveals 68% decline in global wildlife populations since 1970

Photo, posted May 7, 2020, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

An Environmental Victory In Cameroon | Earth Wise

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The Ebo Forest in Cameroon is one of the last intact forests in central Africa and is a biodiversity hotspot, home to hundreds of rare plants and animal species, including tool-using Nigeria-Cameroon chimpanzees, western gorillas, forest elephants, red colobus monkeys, and giant goliath frogs.  The 600 square miles of mountain slopes and river valleys are covered by thick tree canopies that shelter a fascinating array of species.

This past July, Cameroon Prime Minister Joseph Dion Ngute signed a decree that turned half of the Ebo Forest into a so-called forest management unit, meaning that the government could begin to sell logging concessions.

However, on August 11, Ngute, at the direction of President Paul Biya, withdrew the decree, suspending any logging plans.  President Biya also ordered a delay to reclassify an additional 160,000 acres of the Ebo, which might have opened up even more forest for logging.

Apart from its rich biodiversity, the Ebo Forest is culturally and societally important for the Banen Indigenous people, who consider it to be their sacred ancestral home.  The Banen were ousted from the forest in the 1960s but took up settlements just a few miles from its borders.  They still rely on the forest for food and medicines.  Meanwhile, the proximity of the forest to big cities makes it an easy target for bushmeat poachers.

Both conservation groups and indigenous leaders welcomed the withdrawal of the decree but remain concerned about the future of the Ebo Forest.  Conservation groups hope that the international community will seize the opportunity to work with the government of Cameroon to make the Ebo Forest a permanent showcase for long-term conservation in harmony with very challenged communities.

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Cameroon Cancels Plan to Log Half of the Ebo Forest, a Key Biodiversity Hotspot in Central Africa

Photo, posted September 17, 2005, courtesy of Salva le Foreste via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disappearing Rainforests | Earth Wise

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Forest loss is a major contributor to climate change, and it is continuing at a rapid pace.  The tropics lost about 30 million acres of tree cover in 2019, a third of which was within humid tropical primary forests, which are especially important for biodiversity and carbon storage.  To put that loss in a human-scale perspective, it is the equivalent of losing a football field of primary forest every six seconds for the entire year.

The losses last year were 2.8% higher than in the previous year, and these losses have continued over the past 20 years despite worldwide efforts to halt deforestation.  

Brazil single-handedly accounted for over a third of all global loss of humid tropical primary forests. Bolivia experienced record-breaking tree cover loss due to fires.  The losses in its forests were 80% greater than in any previous year.  The fires were often started by people who were trying to clear land for agriculture but had the fires go out of control. Several countries in Africa’s Congo Basin also experienced sustained or worsening forest loss. 

Indonesia, often the focus of the world’s attention for its deforestation activities, actually saw a 5% reduction in primary forest loss in 2019.  It was the third year in a row for lower losses.  The now-permanent moratorium on clearing forests for oil palm plantations and logging seems to be working.

Going forward, the coronavirus pandemic poses additional threats to the world’s forests in the near future.  There may be a tendency to sacrifice forests in pursuit of economic recovery, which will only lead to future complications for the health and livelihoods of millions of people around the world.

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We Lost a Football Pitch of Primary Rainforest Every 6 Seconds in 2019

Photo, posted February 7, 2011, courtesy of Chad Skeers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Malaria With Gene-Drive Technology | Earth Wise

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Malaria continues to be a major health hazard throughout the tropical and subtropical regions of the world. There were 228 million cases of malaria in 2018 and over 400,000 deaths. 

Malaria is a mosquito-borne infectious disease spread by 40 of the world’s 3,500 mosquito species.  So, efforts to control mosquito populations are the primary strategy to eradicate malaria.

A team led by Imperial College London has created a genetic modification that distorts the sex ratio of a population of Anopheles gambiae mosquitoes using “gene drive” technology.  The modification works by using a DNA-cutting enzyme to destroy the X chromosome during the production of sperm, which leads to predominantly male offspring, since females require two X chromosomes.  The modification is coupled to a gene drive to allow it to spread through a population in a very effective way.  A gene drive is a genetic engineering technology that propagates a particular modification by assuring that a specific form of a gene (or allele) will be transmitted with far more than the natural 50% probability.

The result of this is that mosquitoes produce more male offspring, eventually leading to no females being born and a total collapse in the population. The mosquitoes studied are the main malaria vector in sub-Saharan Africa.  The hope is that mosquitoes carrying a sex-distorter gene drive would be released in the future, spreading the male bias with local malaria-carrying populations and causing them to collapse.  Only female mosquitoes bite and take blood meals.  If the gene drive technology works in the field, it could be a game-changer in the fight to eliminate malaria.

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Malaria mosquitoes eliminated in lab by creating all-male populations

Photo, posted June 20, 2014, courtesy of 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.

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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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.

Fresh Water Under The Sea

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A new survey of the sub-seafloor off the U.S. Northeast coast has revealed the existence of a gigantic aquifer of relatively fresh water trapped in porous sediments lying beneath the salty ocean.  This appears to be the largest such formation ever found.

The newly-discovered aquifer stretches from the shore at least from Massachusetts to New Jersey and extends more-or-less continuously out about 50 miles to the edge of the continental shelf.   The deposits begin at around 600 feet below the ocean floor and bottom out at about 1,200 feet.  If all that water was found on the surface, it could create a lake some 15,000 miles in area.  The researchers estimate that the region holds at least 670 cubic miles of fresh water.

Researchers made use of innovative measurements of electromagnetic waves to map the water, which had not been detected by other technologies.   It was already known that fresh water existed in places under the sea bottom as a result of oil drilling as far back as the 1970s.  But there was previously no hint of the extent of the undersea aquifer. 

The water probably was trapped by sediments deposited during the last ice age when sea levels were much lower.  But modern subterranean runoff from land sources might also be a contributor.

If water from the aquifer was to be withdrawn, it would still have to be desalinated for most uses, but the cost would be much less than processing ordinary seawater.  There is probably no need to do this in the Northeastern US, but the discovery suggests that such aquifers probably lie off many other coasts worldwide and could provide desperately needed water in places like southern California, Australia, the Mideast or Saharan Africa.

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Scientists Map Huge Undersea Fresh-Water Aquifer Off U.S. Northeast

Photo, courtesy of August 1, 2015, courtesy of Michael Vadon 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...)