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A Smart Window | Earth Wise

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Researchers at Oxford University have developed a new adaptable smart window technology that has the potential of reducing the energy usage of the average home by a third.

The technology uses a spectrally tunable low-emissivity coating that can control the amount of heat that comes into a room without affecting the quality of the light that enters.

The thermal energy from the sun’s infrared rays is absorbed by the glass and then is re-emitted as heat.  That heat can either be used to warm the room using transparent electrical heaters embedded in the glass or can be reflected away to cool the room.  The windows can change according to seasonal needs.

The researchers built a prototype using a material called an active chalcogenide-based phase change material.  When it is cold, the infrared rays from the sunlight are harvested and used to heat the building.  When it is warm, the new glass can switch state to reflect the heat and reduce the need for air conditioning.  The active phase change material is adjustable so that the amount of heat absorbed or reflected can be tuned for precise temperature control.  There is essentially no effect on visible light passing through the window.  Current low-emissivity glass for windows can reduce heat transfer, but its properties cannot be altered according to seasonal needs.

The researchers estimate that using windows fitted with the new prototype glass – including the energy required to control the film – would save 20 to 34% in energy usage annually compared to double-glazed windows found in many modern homes.

A spinout company from Oxford called Bodle Technologies is collaborating with two existing industrial partners to develop the technology further.

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New adaptable smart window coating could help heat or cool a home and save energy

Photo, posted April 26, 2008, courtesy of Lima Andruska via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Healthy Soil Is Healthy For People | Earth Wise

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A new study by researchers at the University of Washington looked at the impact of regenerative farming practices on the nutritional content of the food that is grown. 

Regenerative agriculture involves farming practices that not only “do not harm” to the land but actually improve it by regenerating and revitalizing the soil.  The practices focus on topsoil regeneration, increasing biodiversity, improving the water cycle, and enhancing ecosystem services.  Examples are soil-building techniques that minimize plowing, the use of cover crops, and the planting of diverse crops rather than monocultures.

The study included 10 farms across the U.S. that followed soil-friendly practices for at least five years. The results were that the crops from those farms had a healthier nutritional profile than the same crops grown on neighboring, conventional farms.  In particular, there was a boost in certain minerals, vitamins and phytochemicals that are beneficial to human health.  Across the board, regenerative practices resulted in crops with more anti-inflammatory compounds and antioxidants.

The participating farms grew one acre of a test crop – peas, sorghum, corn, or soybeans – for comparison with the same crop grown on a neighboring farm using conventional agriculture.  Analysis showed that the farms practicing regenerative agriculture had healthier soils, as measured by their organic matter – or carbon – content and by other tests. 

Organic farms avoid chemical pesticides, but they operate with a variety of farming processes.  Nonetheless, they have also been found to produce crops with higher levels of beneficial nutrients.  The biology of the soil in which crops are grown is an important factor for human health.  It isn’t just what we eat that matters; it is how we grow it.

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Farms following soil-friendly practices grow healthier food, study suggests

Photo, posted January 10, 2020, courtesy of Les via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Corn Ethanol And The Climate | Earth Wise

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The Renewable Fuel Standard legislation, first passed in 2005 and updated in 2007, requires billions of gallons of renewable fuel to be added to the country’s transportation fuel supplies.  It created the world’s largest biofuels program.

The standard was hailed as a major victory for the climate as well as a way to reduce our dependence upon foreign oil.

The intent of the legislation was to encourage various forms of renewable fuels – especially cellulosic ethanol from plant and wood fiber – to become an increasing part of the fuel mix.  That has yet to happen.  Instead, corn ethanol has been the backbone of the program.

Back in 2007, the EPA determined that ethanol from corn would lead to a 20% reduction in greenhouse gases compared to gasoline.  But the next year, a study published in the journal Nature projected that corn ethanol would double greenhouse gas emissions over 30 years because demand for corn would drive farmers to plow up increasing amounts of carbon-rich forest and grassland.

A new study published by researchers at the University of Wisconsin, Madison, has again concluded that corn-based ethanol may actually be worse for the climate than fossil-based gasoline as well as having other environmental downsides.  According to the study, since the fuel standard was passed, farmers have expanded corn production on nearly 7 million acres each year, causing the conversion of lands to cropland.  The result is that the carbon intensity of corn ethanol could be as much as 24% higher than gasoline.

The issue is still being debated in Congress, but if these results are verified, the time has come to revamp the terms of the renewable fuel standard.

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Corn-Based Ethanol May Be Worse For the Climate Than Gasoline, a New Study Finds

Trots den höga effektiviteten leder inte vissa patienter som tar läkemedlet till en förbättring av erektion. Detta beror på felaktig användning av medicinen eller på att ED helt enkelt är en följd online apotek viagra av en annan sjukdom. I sådana fall är det obligatoriskt att konsultera och undersöka en läkare.

Photo, posted October 23, 2011, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is It Really Getting Warmer? | Earth Wise

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The primary indicator of global climate change is the Global Mean Surface Temperature of the Earth and the world’s nations are trying to keep its increase below 1.5 degrees Celsius over the pre-industrial level.   That rise in temperature is called the Global Surface Temperature Anomaly and it actually reached an all-time high in 2016 at 1.02 degrees before going back down.

At this point, you might be saying, “hold on there…  it hasn’t gotten larger over the past 5 years?”  What’s going on?

The global climate is pretty complicated and there are many things that influence it.  One of the most significant factors is the El Niño Southern Oscillation or, more familiarly, the El Niño.  The El Niño is a periodic and irregular variation in the sea surface temperature of the tropical eastern Pacific Ocean driven by persistent westerly winds.  When an El Niño is happening, currents move to the west coast of South America and warm the tropics and subtropics.  This causes a spike in the global mean temperature.  There was a strong El Niño in 2016.

On the other hand, when easterly winds dominate to form a La Niña, cool water comes up from the depths of the Pacific and cools the atmosphere.  In 2017 and 2018, there was a fairly strong La Niña, lowering the global mean temperature.  2020 had no El Niño or La Niña, and the global temperature went back up to its previous peak.  Last year, there was again a La Niña and the temperature dipped again.

The global mean surface temperature has been rising in the industrial era, but it also fluctuates with the complicated dynamics of the Pacific Ocean.

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Why Isn’t It Getting Warmer?

Photo, posted February 12, 2016, courtesy of Amit Patel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Levels Of Deforestation In The Amazon | Earth Wise

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The Amazon rainforest is the largest rainforest in the world, covering more than 2.5 million square miles.  It’s home to 10% of all known species in the world.  The Amazon rainforest’s biodiversity is so rich that scientists are still discovering new plant and animal species today.  

The Amazon rainforest absorbs huge amounts of carbon dioxide from Earth’s atmosphere, making it a key part of mitigating climate change.  The vast rainforest acts as what’s known as a carbon sink.  Simply put, a carbon sink is anything that absorbs more carbon from the atmosphere than it releases.  But as trees in the Amazon disappear, so does the ability of the rainforest to absorb carbon dioxide.

Deforestation of the Amazon rainforest remains a major problem.  According to satellite data from the Brazilian government, the number of trees cut down in the Brazilian Amazon in January far exceeded deforestation figures for the same month last year.  Approximately 166 square miles of land was deforested in January alone, which is five times greater than what was lost in January, 2021.

Cattle ranching – both for beef and for leather – remains the leading cause of deforestation in the Amazon rainforest.  Trees in the Amazon are also cut down for their wood, as well as to clear the land in order to grow food crops, such as soy, sugar, and oil palm. 

Many companies have pledged to achieve “net zero” deforestation in their supply chains over the years, but most have not lived up to the commitment. 

Deforestation is not only a major driver of climate change, but it’s also the leading cause of species extinction.  Preserving the Amazon rainforest is vital. 

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Amazon deforestation: Record high destruction of trees in January

Greenpeace calls on fast food giants to take a stand against Bolsonaro’s Amazon destruction

Hundreds of Companies Promised to Help Save Forests. Did They?

Photo, posted July 14, 2018, courtesy of Alexander Gerst via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Car Sales Surge | Earth Wise

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During the fourth quarter of 2021, overall auto sales in the US fell by 21.3% compared to the same quarter of 2020.  At the same time, sales of electric cars grew by 73%.  Is this the beginning of the end for the Gasoline Era, or was it a just an anomaly during the COVID pandemic?

The biggest factor for the big drop in car sales was probably on the supply side.  The ongoing chip shortage as well as other supply-chain problems made it difficult to find many desired vehicles.  Meanwhile, the soaring electric car sales in the US was mostly soaring Tesla sales.  According to Kelley Bluebook, 72% of all electric cars sold in the US in the fourth quarter were Teslas.  For a number of reasons related to its in-house software development and it unified computer architecture, the chip shortage has been far less of a problem for Tesla than for other car brands.  So, Tesla bucked the overall market decline because it actually had cars to sell.

So, once these supply-chain issues are resolved, will the car market return to “normal”?  That is actually unlikely.  Apart from the short-term issues, there are long-term factors that are changing the automobile market.

There is far more public attention on EVs these days.  Multiple commercials during the Superbowl demonstrated that.  All the carmakers are gearing up for an electric future as government policies push for it.   Electric vehicle sales are already booming in Europe.  Cars are fashion products and electric cars are the latest trend.  Electric car sales will continue to grow at an impressive pace this year.  According to many observers, the recent trend could be the beginning of an avalanche.

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US Electric Car Sales Surge As Overall Car Sales Slip — A Game-Changing Trend?

Photo, posted July 28, 2017, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Offshore Wind Ramping Up In The Northeast | Earth Wise

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There is a growing number of large offshore wind projects in the pipeline in the Northeast.  The large Vineyard Wind project off the coast of Massachusetts began construction in November.  Contracts for the Empire Wind and Beacon Wind projects in New York were finalized in January.

The first offshore wind project to begin construction in New York broke ground in February.  South Fork Wind, a 132-megawatt project located about 19 miles southeast of Block Island, Rhode Island, is expected to come online in 2023.

New York’s goal is to develop 9 gigawatts of offshore wind by 2035 and the state is investing $500 million to set up manufacturing and supply chain infrastructure for offshore wind.  Major facilities will be built in the South Brooklyn Marine Terminal and in the Port of Albany.

Meanwhile, Massachusetts recently announced that the site of the last coal-fired power plant in that state will become the home of its first offshore wind manufacturing facility.

The Brayton Point power plant in Somerset was shut down in 2017 after more than 50 years of operation.  The site, located on Mount Hope Bay near Providence, Rhode Island, will host a $200 million facility for the manufacturing of undersea transmission lines used to connect the grid to offshore wind turbines.  The first of these will be the Vineyard Wind’s Commonwealth Wind project, which will generate 1.2 gigawatts of electricity.

Both New York and Massachusetts are investing in the opportunities afforded by the soon-to-be booming offshore wind industry.  With numerous windfarms planned up and down the Atlantic coast, manufacturing, maintenance, and support infrastructure will be big business for the two states.

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Work starts on New York’s first offshore wind project

Former Coal Power Site in Massachusetts to Become Offshore Wind Plant

Photo, posted May 13, 2011, courtesy of SSE via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Koalas Are Endangered | Earth Wise             

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The koala is one of the world’s most iconic animal species and is widely considered to be the symbol of Australia.   Koalas are not bears; they are marsupials. 

Being iconic symbols is not sufficient to prevent koalas from going extinct.  In the 1920s, hundreds of thousands of koalas were shot for the fur trade, greatly reducing their population.

More recently, drought, bush fires, disease, and habitat loss have drastically reduced the numbers of koalas.  Since 2018, there has been a 30% decline in koala populations across Australia.  It is difficult to get an accurate count of the animals because they don’t move around much, and they live high up in tree canopies where they are hard to spot.

 Estimates are that the koala population has dropped from between 45,000-82,000 in 2018 to between 32,000-58,000 in 2021.  The koala is now extinct in 47 Australian electorates and in many others, there are only handfuls of animals remaining.   The population decline was accelerated by devastating wildfires in late 2019 into early 2020.  Some estimates are that koalas could be extinct by 2050.  Conservation organizations around the world have been demanding greater protection for koalas for years.

Given this dire situation, the Australian government recently declared the koala an endangered species, reclassifying it from being a vulnerable species.  The government plans to adopt a recovery plan that will include new laws protecting koalas and their natural woodland environments.  The details of the plan remain to revealed.

According to the Australian Koala Foundation, however, the new status of the koala means very little in and of itself.  If the clearing of the koala habitat continues, the species has little chance of surviving in the wild.

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‘In rapid decline’: Australia has lost 30% of its koalas in just 3 years, foundation says

Australia Declares Koalas an Endangered Species

Photo, posted September 18, 2019, courtesy of Guido Konrad via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Permafrost Thaw | Earth Wise

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We’ve talked about permafrost before.  It is the frozen soil, rock, or sediment piled up in the Arctic that has been there at least for two years but, for the most part, for millennia or even over a million years.  Permafrost holds the carbon-filled remains of vegetation and animals that froze before they could start decomposing.   Estimates are that there are nearly 2,000 billion tons of carbon trapped in Arctic permafrost.  To put that in perspective, annual global carbon emissions are less than 40 billion tons.

Keeping all that carbon frozen plays a critical role in preventing the planet from rapidly heating. The ongoing warming of the Arctic is causing the subsurface ground to thaw and release long-held carbon to the atmosphere.

Scientists from Europe and the US are working together to better track permafrost carbon dynamics.  They are trying to understand the mechanisms that lead to abrupt thaws in the permafrost that have taken place in some locations.  These rapid thawing events are not well understood.  Researchers are also studying the effects of the increasingly frequent wildfires in the Arctic on the permafrost.

Researchers are using satellites to better understand the effects climate change is having on the Arctic environment and how these changes, in turn, are adding to the climate crisis.  Permafrost cannot be directly observed from space, so that its presence has to be inferred from measurements like land-surface temperature and soil moisture readings.  Terrestrial observations are also necessary for understanding how greenhouse gases – both CO2 and methane – are being emitted from the Arctic.

Thawing permafrost is a ticking timebomb for the environment that demands the growing attention of the scientific community.

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Permafrost thaw: it’s complicated

Photo, posted January 24, 2014, courtesy of Brandt Meixell / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lighted Nets Protect Marine Wildlife | Earth Wise

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Gillnets are walls or curtains of netting that hang in the water to trap fish.  They are one of the most extensively used fishing gear in coastal regions throughout the world’s oceans.  While they are very effective at catching targeted fish species, they are not discriminating.  As a result, they carry significant risk of bycatch – the accidental capture of unwanted species as well as other interactions with various marine animals.

Researchers from The Wildlife Conservation Society, NOAA Fisheries, Arizona State University, and the National Fisheries and Aquaculture Institute of Mexico have recently published a study showing that using lighted gillnets reduced overall bycatch by 63%, including a 95% reduction in sharks, skates, and rays, and an 81% reduction in Humboldt squid. 

Gillnets often catch endangered, threatened, and protected species such as sharks, sea turtles, marine mammals, and seabirds, as well as unwanted species and non-marketable juvenile target fish species.  The bycatch animals are often dead or injured and are generally dumped overboard.

Illuminating gillnets with LED lights has emerged over the past decade as an effective tool to reduce bycatch of endangered sea turtles.  The new study is the first detailed examination of the effectiveness of illumination for other vulnerable species.

Gillnets are ubiquitous because they are inexpensive and catch everything that passes them.  Global populations of sharks, skates, and rays have declined as a result of bycatch and illegal fishing. The results of this study are encouraging because they provide a practical solution for increasing the selectivity of gillnets and avoiding bycatch. 

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Lighted Nets Dramatically Reduce Bycatch of Sharks and Other Wildlife While Making Fishing More Efficient

Photo, posted September 19, 2015, courtesy of Jim Bahn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Poverty And Climate Change

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According to the World Health Organization, climate change is expected to cause approximately 250,000 extra deaths per year between 2030 and 2050.  But climate change does not affect everyone the same.  In fact, the poorest people on the planet, who are often the least to blame for climate change, typically bear the worst of the impact.

Wealthier people and countries have more resources to shield themselves from the impacts of climate change.  For example, higher incomes allow people to purchase air conditioning as temperatures rise,  food as food prices soar, and homes in safer places.  Wealthy nations can also compensate citizens when climate change harms livelihoods. 

According to new research, people with lower incomes are exposed to heat waves for longer periods of time compared to those with higher incomes due to a combination of factors including location and access to heat adaptations like air conditioning.  This inequality is expected to increase as temperatures rise. 

The study, which was published in the AGU journal Earth’s Future, found that lower income populations face a 40% higher exposure to heat waves than people with higher incomes.  By the end of the century, the poorest 25% of the global population will be exposed to heat waves at a rate equivalent to the rest of the population combined.

On the other hand, the highest-income quarter of the population will experience comparatively little change in exposure to heat waves as their ability to keep up with climate change is generally greater.

The research team hopes its findings will prompt innovations into affordable cooling solutions for the world’s most vulnerable population. 

Climate change and poverty are, and will remain, inextricably linked. 

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Poorest people bear growing burden of heat waves as temperatures rise

Photo, posted October 27, 2019, courtesy of Jack via Flickr.

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Beavers Are Flooding The Warming Arctic | Earth Wise

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The accelerating warming in the Arctic has transformed the region into a warmer, wetter, and more diverse environment.  Warming temperatures have encouraged the increasing growth of vegetation, particularly shrubs that provide beavers with bark to eat and branches to build with.  Warming temperatures also mean that lakes and streams freeze solid for shorter periods of time or not at all, allowing beavers to pursue their construction projects for longer periods during the year.

Prior to the mid-1970s, residents of the Alaskan Arctic encountered few beaver ponds.  In 2018, researchers using satellite imagery mapped 12,000 beaver ponds in Alaskan tundra.

Beavers are causing major changes in the streams and floodplains that many small Alaskan villages depend upon for food, water, and navigation.  As the rodents transform lowland tundra ecosystems, they are eliminating food sources, deteriorating water quality, and making it difficult to navigate waterways.

The migration of beavers across the Arctic landscape is largely a result of climate change.  But it is also becoming one of the factors amplifying climate change.  Scientists are trying to figure out the degree of permafrost thawing that beaver dam-and-den building is causing and how fast these defrosted organic soils will degrade and release trapped carbon and methane.

Beaver dams alter the hydrology of streams by slowing the flow, storing and spreading water to create wetlands, raising the water table, and lowering the oxygen content of the water. 

Climate-driven changes in species distributions affect human well-being as entire ecosystems continue to change.  Shifts in animal habitat stimulated by climate change could have profound consequences across the globe.

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Beavers Are Flooding the Warming Alaskan Arctic, Threatening Fish, Water and Indigenous Traditions

Photo, posted June 12, 2018, courtesy of Peter Pearsall/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And The World’s Fisheries | Earth Wise

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According to a new study, approximately 70% of the world’s oceans could be suffocating from a lack of oxygen by 2080 as a consequence of climate change.  This has the potential to impact marine ecosystems all around the world.  

The study, which was recently published in the journal Geophysical Research Letters, is the first to use climate models to predict how and when deoxygenation will occur throughout the world’s oceans outside of its natural variability. 

According to the findings, significant and potentially irreversible deoxygenation of the ocean’s middle depths began occurring last year.  The models predict that deoxygenation will begin affecting all zones of the ocean by 2080.

According to the study’s models, mid-ocean depths are already losing oxygen at unnatural rates. Globally, the ocean’s middle depth – known as the mesopelagic zone – is home to many of the world’s commercially fished species.  This makes these new findings a potential harbinger of economic hardship, seafood shortages, and environmental disruption. 

Just like land animals, aquatic animals need oxygen to breathe.  As climate change warms the oceans, the water holds less oxygen and is more buoyant than cooler water.  This leads to less mixing of oxygenated water near the surface with deeper waters, which naturally contain less oxygen.  Warmer water also raises oxygen demand among living organisms, resulting in less availability for marine life. 

The researchers also found that oceans closer to both the North Pole and the South Pole are particularly vulnerable to deoxygenation.  While they are not yet sure why, accelerated climate warming could be the culprit. 

These findings should add new urgency to climate change mitigation efforts. 

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Climate change has likely begun to suffocate the world’s fisheries

Photo, posted January 28, 2019, courtesy of Joseph Gage via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

January Climate Report Card | Earth Wise

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January was the sixth-warmest January in the 143 years of global climate record keeping.  The global land and ocean surface temperature was 1.6 degrees Fahrenheit above the 20th century average.

Meanwhile, the United States had its coolest January since 2014, although the month still ranked nearly a degree above the long-term average across the nation.  This January was also the driest January in eight years and was one of the top- 15 driest Januarys on record.  That being said, there was the so-called Bomb Cyclone late in the month that dumped 1-2 feet of snow and brought blizzard conditions along the eastern seaboard and set a one-day snowfall record in Boston.

Global conditions and regional and local conditions can be very different.  In the big picture, January was the 46th consecutive January and the 445th consecutive month with temperatures above the 20th century average.

And while the US had a fairly cool January, South America saw its second-warmest January on record, Asia had its fourth warmest, and Oceania had its seventh warmest.

Apart from temperatures, Antarctic sea ice coverage was the second smallest January extent in 44 years.  Arctic ice was 208,000 square miles below the 1981-2010 average, although it was the largest since 2009.

Even as the global climate warms, local and regional climate conditions will continue to have unique and variable characteristics over the course of time.  Every time there’s a bout of cold weather, it isn’t time to stop being concerned about climate change.

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January 2022 was Earth’s 6th warmest on record

Photo, posted January 6, 2013, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mercury In The Amazon Rainforest | Earth Wise

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Recent research has found that some of the highest levels of mercury pollution ever recorded are in a patch of pristine Amazonian rainforest.  The international team of researchers discovered that illegal goldmining in the Peruvian Amazon is the source of the pollution.

Illegal miners separate gold particles from river sediments using mercury.  Mercury binds to gold, forming pellets large enough to be caught in a sieve.   The pellets are then burned in open fire ovens, releasing the mercury to the atmosphere, leaving the gold behind.  The mercury smoke ends up being washed into the soil by rainfall, deposited onto the surface of leaves, or directly absorbed into leaf tissues.

Deforested areas had low levels of mercury, while the areas with the largest, densest old-growth trees captured huge volumes of atmospheric mercury, more than any other ecosystem studied in the entire world.  Mercury levels were directly related to leaf area index:  the denser the canopy, the more mercury it holds.  Birds from this area have up to twelve times more mercury in their systems than birds from less polluted areas.  Such high concentrations of mercury could provoke a decline of up to 30% in these birds’ reproductive success.

Small-scale artisanal gold mining is an important livelihood for local communities.  Eliminating it outright may not be a viable solution but coming up with ways to continue to provide a sustainable livelihood while protecting communities from poisonous pollution is essential.

In the meantime, the forests are doing an important service by capturing much of the mercury and preventing it from getting into the general atmosphere and endangering more people and animals.  Burning or harvesting the mercury-ridden trees would release the mercury back into the atmosphere.

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Modern Day Gold Rush Turns Pristine Rainforests into Heavily Polluted Mercury Sinks

Photo, posted August 24, 2016, courtesy of Anna and Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tourism And Invasive Species | Earth Wise

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Tourism has experienced exponential growth during the past 70 years.  In 1950, there were 25 million international tourist arrivals.  By 1990, it had ballooned to 435 million.  Between 1990 and 2018, the numbers more than tripled reaching more than 1.4 billion.  And by 2030, the number of international tourist arrivals is expected to reach 1.8 billion.

Tourism is vital to the success of many economies around the world.  Tourism can boost revenue, provide jobs, develop infrastructure, protect wildlife, and help preserve heritage sites and cultures.  But there can also be many downsides to tourism, one of which is that it can contribute to the introduction and spread of invasive species.  Non-native organisms can cause all sorts of social, environmental, and economic damage.   

Tourists help spread invasive organisms far and wide.  These organisms hitch rides in their luggage and on their shoes and clothing.  A 2011 study in New Zealand found that for every gram of soil on the shoes of in-bound international passengers, there were 2.5 plant seeds, 41 roundworms, 0.004 insects and mites, and many microorganisms. 

A new study by researchers from the University of Melbourne in Australia and AgResearch New Zealand examined to what degree tourism plays a role in the spread of invasive species.  According to the study, which was recently published in the journal NeoBiota, the research team found that the number of nights spent in hotels significantly correlated to the incursion of invasive species during that period.

Creating effective mechanisms to prevent the introduction of invasive species in the first place is the best way to prevent this problem. 

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Unwelcome guests: International tourism and travel can be a pathway for introducing invasive species

Number of tourist arrivals

Photo, posted March 27, 2005, courtesy of John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree Diversity | Earth Wise

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Scientists have estimated that there are more than 8 million species of plants and animals in existence.  Amazingly, only about 1.2 million of them have been identified and described so far and most of those are actually insects.  Millions of other organisms have yet to be discovered.

One would imagine that most of these unknown species are tiny things that are hard to spot or encounter.  But our ignorance of species even applies to trees, which are pretty easy to spot if you encounter them.

A new study involving more than 100 scientists across the globe has produced an estimate of the number of tree species on the Earth.  The new global estimate is that there are 73,000 tree species, which is about 14% more than previously thought.  Based on a combination of data from two global datasets, the study yielded a total of 64,100 documented tree species worldwide.  The researchers then used novel statistical methods to estimate the total number of unique tree species at biome, continental, and global scales, which includes species yet to be discovered and described by scientists.  Therefore, the estimate predicts that there are likely to be over 9,000 tree species still to be found.

Roughly 40% of the undiscovered tree species are likely to be in South America, which is the continent with the highest number of rare tree species and the highest number of continentally endemic tree species – meaning those found only on that continent.  Hot spots of undiscovered tree species are likely the tropical and subtropical moist forests of the Amazon basin and the Andes-Amazon interface.

Extensive knowledge of tree richness and diversity is key to preserving the stability and functioning of ecosystems.

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Number of Earth’s tree species estimated to be 14% higher than currently known, with some 9,200 species yet to be discovered

Photo, posted November 5, 2017, courtesy of Deensel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaning Up Abandoned Wells | Earth Wise      

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There are 130,000 documented abandoned oil and gas wells in the US, according to the Department of the Interior.  The key word is documented.  According to an EPA study in 2018, the actual number of abandoned wells could be as high as two or three million.  According to an analysis by the Environmental Defense Fund and McGill University, about nine million people in the United States live within a mile of one of these wells.

Some of these wells might be fairly harmless, and others might be quite dangerous.  Wells can emit a variety of gasses, including methane, which is a far stronger greenhouse gas than carbon dioxide.  Leaking wells are a major source of air and groundwater pollution.  Apart from methane, substances such as arsenic can continue to leak from wells even after they are no longer operational.

At the end of January, the Biden Administration announced a series of new actions to tackle methane pollution.  Among these measures is $1.15 billion in funds from the Department of the Interior that states can use to seal up abandoned oil and gas wells.  That funding comes from the Bipartisan Infrastructure Law passed in November, which sets aside $4.7 billion for a federal program dedicated to orphaned wells.

Addressing the largely ignored problem of abandoned wells is important from the standpoint of climate pollution as well as human health.  Efforts to plug the wells will also provide high-paying jobs

Other methane-reduction measures include increased enforcement from the Department of Transportation on reducing pipelines leaks, research funding for limiting methane emissions from beef and dairy farming, and technical assistance from the Department of Energy on well-plugging efforts.

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Photo, posted March 23, 2011, courtesy of David Stone via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antarctic Ice Collapse | Earth Wise

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In Antarctica, a huge chunk of the Larsen B Ice Shelf collapsed suddenly and spectacularly in January.

The Larsen Ice Shelf is located on the northeastern side of the Antarctic Peninsula on the Weddell Sea.  It was formed over the course of more than 12,000 years.  The Weddell Sea used to be a completely frozen body of water.  The famous Ernest Shackleton expedition in 1915 was trapped in its ice.  But the Antarctic Peninsula has been steadily warming in recent decades.

The Larsen A Ice shelf collapsed in 1995 and the 1,250-square-mile Larsen B Ice Shelf collapsed in 2002.  After that event, a portion of the detached ice shelf refroze in 2011 and was attached to the Scar Inlet Ice Shelf.  The refrozen ice was called the Larsen B embayment.

In January, the embayment broke apart, taking with it a portion of the Scar Inlet Ice Shelf.  It disintegrated within a matter of days.  The combined Larsen Ice Shelves – called A, B, C, and D – once extended along a 1000-mile stretch of the eastern Antarctic Peninsula.  Since 1995, it has shrunk from 33,000 square miles to 26,000 square miles.

These ice shelves float on the ocean, so their loss does not actually increase global sea levels.   However, the shelves act as dams that hold back glaciers located on the land behind them.  The loss of Antarctic ice shelves dramatically increases the rate at which glaciers flow into the sea, and that does increase global sea levels. 

Now that the sea ice from the Larsen B embayment is gone, it is likely that there will be additional inland ice losses from the newly exposed glaciers.

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Remnant of Antarctica’s Larsen B Ice Shelf Disintegrates

Photo, posted February 13, 2018, courtesy of NASA/Nathan Kurtz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Spring Is Coming Earlier In Britain | Earth Wise

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The United Kingdom has some of the most detailed records of seasonal changes anywhere in the world.  Since the 18th century, observations of seasonal changes have been recorded by scientists, naturalists, amateur and professional gardeners, and organizations such as the Royal Meteorological Society.  Researchers at two British institutions have collected and collated these records into a database they call Nature’s Calendar, which currently has about 3.5 million records going back to 1736.

By analyzing more than 400,000 observations of 406 plant species in Nature’s Calendar, they found that the average first flowering date from 1987 to 2019 is a full month earlier than the average from 1753 to 1986.  The change correlates very well with rising global temperatures.

The ecological risks associated with earlier flowering times are high.  When plants flower too early, a late frost can kill them – a phenomenon most gardeners have experienced at some point or another.  Beyond that, plants, insects, birds, and other wildlife have co-evolved to be synchronized with plants in their development stages.  A certain plant flowers and attracts a certain kind of insect, which then attracts a particular kind of bird, and so on.  If plants get out of sync with the animals in the ecosystem and the animals can’t change their behavior quickly enough, it can lead to species collapse.

If global temperatures continue to increase at their current rate, spring in the UK could eventually start in February, creating serious problems for many of the species that inhabit forests, gardens, and farms.  The dangers of climate change are not just about extreme weather.

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UK plants flowering a month earlier due to climate change

Photo, posted February 1, 2012, courtesy of Mandy 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...)