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A New Method of Refrigeration | Earth Wise

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Salting roads before winter storms is a familiar sight in the Northeast.  The purpose is to change the temperature at which ice can form on the road.  The underlying concept has formed the basis of a new method of refrigeration that has been dubbed “ionocaloric cooling.”

It is described in a paper published in the journal Science by researchers at the Lawrence Berkeley National Laboratory.  The method takes advantage of how energy in the form of heat is either stored or released when a material changes phase – such as water changing from ice to liquid and vice versa.  Melting absorbs heat from the surroundings while freezing releases heat.  An ionocaloric refrigerator makes use of this phase and temperature change using an electrical current to add or remove ions provided from a chemical salt.

The potential is to make use of this refrigeration cycle instead of the vapor compression systems in present-day refrigerators, which make use of refrigerant gases that are greenhouse gases, many of which very powerful ones.  The goal is to come up with a system that makes things cold, works efficiently, is safe, and doesn’t harm the environment. 

There are a number of alternative refrigeration systems under development that make use of a variety of mechanisms including magnetism, pressure, physical stretching, and electric fields.  Ionocaloric cooling uses ions to drive solid-to-liquid phase changes.

Apart from some very promising theoretical calculations of the system’s potential, the researchers have also demonstrated the technique experimentally.  They have received a provisional patent for the technology and are continuing to work on prototypes to demonstrate its capabilities and amenability to scaling up.

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Berkeley Lab Scientists Develop a Cool New Method of Refrigeration

Photo, posted October 29, 2021, courtesy of Branden Frederick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Flooding | Earth Wise

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Starting in December, a series of “atmospheric rivers” brought record storms to California producing as much rain in three weeks in some areas as they normally have in an entire year.  The historic levels of rain (and snow in the mountains) have swollen rivers, flooded roads and homes, forced evacuations, knocked out electric power for millions of people, and resulted in more than 20 deaths.

Atmospheric rivers are air currents that carry large amounts of water vapor through the sky.  They are not unusual for California but recurrent waves of them like those that have happened recently are very infrequent.  Studies by the U.S. Geological Survey have shown that such a phenomenon recurs in California every 250 years.  There were a series of storms causing disastrous floods in California in 1861-62.

The atmospheric rivers are born in the warm waters of the tropical Pacific.  During La Nina phases, the atmospheric rivers typically make landfall on the northern West Coast. During El Nino phases, atmospheric rivers are more likely to end up in Southern and Central California. During transitions between the phases, as is happening now, the storms can cover large parts of the state.

Modern forecasting is pretty good at predicting the forthcoming occurrence of these storms and has led to some helpful actions, such as reservoir operators preventing dams from overflowing or bursting.  But there is a gap between science and decision-making.  It is pretty clear what needs to be done when tornados or hurricanes are on the way.  It is less clear what actions are appropriate when there are going to be repeated heavy rainstorms.

These storms will have an effect on California’s megadrought, but just how much of an effect remains to be seen.

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Flooding in California: What Went Wrong, and What Comes Next

Photo, posted January 5, 2023, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Global Forest Changes | Earth Wise

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India is one of the most biodiverse countries in the world.  An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species.

India is also one of the 10 most forest-rich countries in the world.  Trees cover approximately 25% of the nation.  But this is still a significant decline from years past.  In fact, between the 1890s and 1990s, a combination of rapid development and resource overexploitation caused India to lose nearly 80% of its native forest area.  Today, as India’s forests continue to disappear, researchers are trying to help preserve what forest remains. 

Using satellite-monitoring data, researchers from The Ohio State University have developed a deep learning algorithm that could provide real-time land use and land cover maps for parts of India. 

The land use monitoring system was trained using satellite data from Norway’s International Climate and Forests Initiative.  By combining this data with a global land cover map produced by Tsinghua University in China, the researcher team’s deep learning model was able to acquire a more detailed type of base map of the area.  Using their model, the researchers were able to process 10 monthly maps.  Their research was recently  presented at the annual meeting of the American Geophysical Union.   

Using these maps, the researchers were able to detect seasonal shifts across india.  These include changes to barren land, how crop land was affected by monsoons, and the distribution of forests in mountainous regions. 

Understanding the impact of these seasonal changes will help scientists better predict the effects of climate change on forests.

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Using deep learning to monitor India’s disappearing forest cover

Photo, posted January 20, 2013, courtesy of Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fertilizing The Ocean | Earth Wise

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There are a variety of schemes for removing carbon dioxide from the atmosphere.  Some require advanced and generally not-very-well developed technology.  Others, such as planting vast numbers of trees, are nature-based but are daunting with respect to the scale to which they need to take place in order to be truly effective.

Researchers at the Pacific Northwest National Laboratory in Richland, Washington have been examining the scientific evidence for seeding the oceans with iron-rich engineered fertilizer in order to feed phytoplankton.  Phytoplankton are microscopic plants that are a key part of the ocean ecosystem.

Phytoplankton take up carbon dioxide as they grow.  In nature, nutrients from the land end up in the ocean through rivers and from blowing dust.  These nutrients fertilize the plankton.  The idea is to augment these existing processes to increase the growth of phytoplankton.  As they eventually die, they sink deep into the ocean, taking the excess carbon with them.


The researchers argue that engineered nanoparticles could provide highly controlled nutrition that is specifically tuned for different ocean environments.  Surface coatings could help the particles attach to plankton.  Some could be engineered with light-absorbing properties, allowing plankton to consume and use more carbon dioxide.

Analysis of over 100 published studies showed that numerous non-toxic, abundant, and easy-to-create metal-oxygen materials could safely enhance plankton growth.  According to the researchers, the proposed fertilization would simply speed up a natural process that already sequesters carbon in a form that could remove it from the atmosphere for thousands of years.  They argue that given the current trends in the climate, time is of the essence for taking action.

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Fertilizing the Ocean to Store Carbon Dioxide

Photo, posted August 2, 2007, courtesy of Kevin McCarthy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Cost Of Heat Waves | Earth Wise

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Heat waves are defined as periods of abnormally hot weather generally lasting more than two days. To be considered a heat wave, the recorded temperatures must be substantially above the historical averages for a given area. According to climate scientists, anthropogenic climate change is likely causing heat waves to increase in both frequency and intensity.  

According to a new study by researchers from Dartmouth University, climate change-driven severe heat waves have cost the world economy trillions of dollars since the early 1990s. 

In the study, which was recently published in the journal Science Advances, researchers combined in-depth economic data for regions worldwide with the average temperature for the hottest five-day period —a commonly used measurement of heat intensity—for each region in each year.  The research team found that between 1992 and 2013, heat waves statistically coincided with variations in economic growth and that an estimated $16 trillion was lost to the effects of high temperatures on human health, productivity and agricultural output.

The results of the study underscore issues of climate justice and inequality.  According to researchers, the economic costs of extreme heat have been and will be disproportionately borne by the world’s poorest nations.  While economic losses due to extreme heat events averaged 1.5% of GDP per capita for the world’s wealthiest regions, the researchers found that low-income regions suffered a loss of 6.7% of GDP per capita.  Most of these low-income nations have contributed the least to climate change. 

According to the research team, immediate action is needed now to protect vulnerable people during the hottest days of the year.

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Heat Waves Have Cost World Economy Trillions of Dollars

Photo, posted July 23, 2021, courtesy of Martin Fisch (marfis75) via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moving Endangered Species | Earth Wise

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People have intentionally or accidentally introduced numerous invasive species to habitats around the world.  At the same time, the planet’s wildlife is in a steep decline.  A recent study estimated that the populations of over 5,000 vertebrate species have declined by an average of nearly 70% since 1970.  A United Nations report warns that human activity has threatened as many as a million species with extinction.

With all of this as a background, there is climate change that is altering the habitats of the world’s species – warming lakes and oceans, turning forests into grasslands, tundra into woodland, and melting glaciers.  In response to these changes, living things are rearranging themselves, migrating to more hospitable locations.  But many species are just not capable of finding more suitable habitats on their own.

Conservationists are now increasingly considering the use of assisted migration. In some cases, when a species’ critical habitat has been irreversibly altered or destroyed, agencies are establishing experimental populations outside of the species’ historical range.  Such actions are often deemed extreme but may be increasingly necessary.

However, clear-cut cases are relatively rare.  More likely, it is a more difficult judgement call as to whether assisted migration is a good idea or is possibly a threat to the ecosystem of the species’ new location.  The relative dearth of assisted migration experiments is less likely a result of legal barriers than it is a lack of scientific and societal consensus on the practice. Scientists are now trying to develop risk-analysis frameworks that various agencies can use in considering potential assisted migration experiments. 

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Last Resort: Moving Endangered Species in Order to Save Them

Photo, posted March 18, 2010, courtesy of Jean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The State Of The Birds | Earth Wise

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The U.S. Committee of the North American Bird Conservation Initiative has published the State of the Birds 2022, an assessment of bird populations in North America. The news is not good.  The report identifies 70 Tipping Point species, which are those that have lost half or more of their breeding population since 1970 and are on track to lose another half or more in the next 50 years. According to research published in Science in 2019, the United States and Canada have lost 3 billion breeding birds since 1970, which is about a quarter of the total population.

More than half of the bird species in the United States are in decline. According to the Conservation Initiative, the tipping point species in particular require proactive conservation protections to avoid becoming endangered.  Species that inhabit grasslands are declining more rapidly, while waterfowl like ducks and geese are actually increasing.  That increase is most likely a result of the investments in conservation funded by the hunting industry.

Those waterfowl gains demonstrate that when there are concerted efforts to protect and promote bird populations, positve changes can happen.  Some say that protecting birds is not a high priority given all the other crises in the world, but what is good for birds is also good for people.  For example, planting trees and other vegetation to enhance bird habitat also helps to sequester carbon, protect coastlines from storm surges, increase groundwater recharge, and reduce urban heating effects.

The loss of 3 billion birds is a major biodiversity crisis and requires action.  Bird conservation benefits wildlife, people, entire ecosystems, and our planet.

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What’s Good for Birds Is Good for People and the Planet. But More Than Half of Bird Species in the U.S. Are in Decline

Photo, posted November 4, 2020, courtesy of Tom Koerner/U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Turning Plastic Into Protein | Earth Wise

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Our planet is choking on plastic.  According to the United Nations, 79% of the 6.3 billion tons of plastic produced every year accumulates in landfills.  Half of all plastic produced is actually designed to be used just once and thrown away.  But plastic is not only accumulating on land.  In fact, the world’s oceans are projected to contain more plastic by weight than fish by the year 2050.     

According to new research, solving the plastic waste issue could help address another prominent global issue: hunger.  A multidisciplinary team of engineers, chemists, and biologists led by researchers from Michigan Tech University has developed a process to break plastics down to be recycled into useful products, including edible protein powder.

The research team’s process converts plastic into compounds using heat and a reactor that deconstructs the material’s polymer chains. The oil-like substance is then fed to a community of oil-eating bacteria.  The bacteria grow rapidly on the oily diet, producing more bacterial cells composed of roughly 55% protein.  This majority-protein byproduct is then dried out and turned into an edible powder.   The end result doesn’t look like plastic at all.  In fact, it resembles a yeast byproduct that comes from brewing beer. 

This research is funded by an award from the US Department of Defense.  The DoD often deploys soldiers in areas where access to food is challenging.  Converting plastic to protein could be part of a solution to that problem. 

While eating something that began as plastic might take some getting used to, it could be part of the solution to both plastic pollution and global hunger.

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Turning Trash Into Treasure: The Plastic to Protein Powder Solution

Beat Plastic Pollution

Photo, posted February 2, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Bengal Water Machine | Earth Wise

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Over the past three decades, the owners of 16 million small farms in the Bengal Basin of Bangladesh have been pumping shallow groundwater during dry seasons to irrigate rice paddies.  By lowering groundwater levels in this way during the dry season, the ability of leakage from rivers, lakes, and ponds to replenish the groundwater was greatly enhanced.   Capturing surface water not only improved the recovery of groundwater levels but only helped to reduce flooding during monsoons.

The net result of this enormous collective groundwater pumping by millions of farmers has been the creation of vast natural reservoirs underground that are comparable to what is contained by many of the world’s largest dams.   This system of sustaining irrigation has transformed what was previously a famine-prone country into a food-secure nation.

The details of this remarkable transformation have been laid out in a study by University College London recently published in the journal Science.  According to the study, over the course of 30 years, more than 75 cubic kilometers of fresh water was captured by this process, which is equivalent to the combined reservoirs of China’s Three Gorges Dam and the Hoover Dam in the U.S.

The authors of the study described the water cycling process as “The Bengal Water Machine” and argue that it can be a sustainable alternative to conventional approaches to seasonal river flow storage for irrigation, which typically involve dams and reservoirs.  Such approaches are difficult to implement in densely populated alluvial plains where sand, silt, and clay are laid down by annual floodwaters. 

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Millions of farmers “replumb” world’s largest delta

Photo, posted February 2, 2010, courtesy of Melanie Ko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cleaning Up Urban Rivers With Nature’s Tools | Earth Wise

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Fifty years after the passage of the Clean Water Act, urban waterways across the United States are continuing their comeback and are showing increasing signs of life.  A strategy that is being adopted in many places is to use natural restoration techniques focused on bolstering plants and wildlife to improve water quality.

A nonprofit called the Upstream Alliance has focused on public access, clean water, and coastal resilience in the Delaware, Hudson, and Chesapeake watersheds.  Working with the Center for Aquatic Sciences and with support from the EPA and the National Fish and Wildlife Foundation, the alliance has been repopulating areas of an estuary of the Delaware River near Camden, New Jersey with wild celery grass, which is a plant vital to freshwater ecosystems.

In many places, scientists, nonprofits, academic institutions, and state agencies are focusing on organisms like bivalves (typically oysters and mussels) along with aquatic plants to help nature restore fragile ecosystems, improve water quality, and increase resilience.

Bivalves and aquatic vegetation improve water clarity by grounding suspended particles, which allows more light to penetrate.  These organisms also cycle nutrients both by absorbing them as food and by making them more available to other organisms.

Underwater restoration projects have been underway in New York Harbor for more than a decade, where the Billion Oyster Project has engaged 10,000 volunteers and 6,000 students. 

The hope is that bringing back bivalves and aquatic plants can create a lasting foundation for entire ecosystems.  It is restoring nature’s ability to keep itself clean.

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How Using Nature’s Tools Is Helping to Clean Up Urban Rivers

Photo, posted December 19, 2019, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Geoengineering Research Plan | Earth Wise

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The 2022 federal appropriations act, signed into law in March, directed the Office of Science and Technology Policy to develop a cross-agency group to coordinate research on climate interventions, in partnership with NASA, the National Oceanic and Atmospheric Administration, and the Department of Energy.

The group is tasked with creating a research framework to “provide guidance on transparency, engagement, and risk management for publicly funded work on solar geoengineering research.”  The group is supposed to develop a five-year plan that will define research goals for the field, assess the potential hazards of climate interventions, and evaluate the level of federal funding required to carry out the work.

This marks the first federally coordinated effort of this kind and is especially significant because it contributes to the perception that geoengineering is an appropriate and important area of research as the climate continues to warm.

It is an understatement to say that such research is controversial.  Geoengineering has often been a taboo topic among scientists. There are significant questions about potential environmental side effects and concerns that the impact of any such efforts would be felt unevenly in different parts of the world.  There are challenging questions about global governance , including who should be able to make decisions about any potential deployment of climate interventions and what the goals of such interventions should be.

These are momentous issues to grapple with, but as the threat of climate change grows and nations continue to fail to make rapid progress on emissions, researchers, universities, and nations are increasingly motivated to seriously explore the potential effects of geoengineering approaches.  We can’t hide from the fact that these issues are going to be explored.

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The US government is developing a solar geoengineering research plan

Photo, posted June 28, 2013, courtesy of Fernando Aramburu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is It Too Late To Save The Vaquita? | Earth Wise

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The vaquita porpoise, the world’s smallest marine mammal, is on the brink of extinction.  Scientists estimate that just 10 or fewer vaquitas are left despite international conservation efforts. Found only in Mexico’s Upper Gulf of California, the vaquita is the most endangered marine mammal on the planet. 

According to the International Committee for the Recovery of the Vaquita, the number one threat facing vaquitas is gillnets. The porpoises get trapped in these nets and drown.  Gillnets are often used illegally in the region to catch shrimp and fish, including the critically-endangered totoaba.  The totoaba’s swim bladder is considered a delicacy in Asia and can fetch thousands of dollars.  Despite Mexico banning both totoaba fishing and the use of gillnets in the vaquitas’ habitat, many say the bans are not always enforced.  

But there is a reason to be hopeful.  According to a genetic analysis led by researchers at UCLA, the critically-endangered species actually remains relatively healthy and can potentially survive if illegal fishing practices cease immediately. 

In the study, which was recently published in the journal Science, the research team analyzed the genomes of 20 vaquitas between 1985 and 2017 and ran simulations to predict the species’ extinction risk over the next 50 years.  The researchers concluded that if gillnet fishing ends immediately, the vaquita has a very high chance of recovery.  If the practice continues, however, even moderately, the likelihood of a recovery plummets. 

According to the research team, the surviving vaquitas are actively reproducing and seem healthy.  But poachers’ gillnets will continue to pose an existential threat to the species until more measures are taken to protect the vaquita. 

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Only 10 vaquita porpoises survive, but species may not be doomed, scientists say

Photo, posted October 18, 2008, courtesy of Paul Olson / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change On Mount Everest | Earth Wise

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Climate change has shown up in the highest place on Earth.  The highest glacier on Mount Everest is rapidly retreating with rising temperatures.

New research by an international team led by the University of Maine and published in the journal Climate and Atmospheric Science has determined that the South Col Glacier atop Mount Everest has shrunk by half since the 1990s.   Its ice mass has thinned by an estimated 180 feet.

The glacier used to be covered by snow, which reflected the sun’s light and insulated the mass of ice under the snow.  But warmer temperatures, lower humidity, and more severe winds have eliminated the snow cover, fueling the decline of the glacier.

The study of the South Col Glacier highlights the critical balance created by snow-covered surfaces and exposes the potential for loss throughout high mountain glacier systems as snow cover is depleted by warming temperatures.  When even the highest glacier on Mount Everest is impacted, it is clear that no place is safe from the warming climate.

The human significance of this development is substantial.  More than 200 million people in Asia depend on meltwater from glaciers in the high mountains of the continent for their freshwater needs.  But now glaciers in the mountains are melting faster than they can be replenished by snowfall.

As for Mount Everest itself, future expeditions on the mountain will face new challenges as glacier melting causes more avalanches and climbers accustomed to digging into ice and snow will need to scale more exposed bedrock.  Climate predictions for the Himalaya in general all anticipate continued warming and continued loss of glacier mass.

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Climate Change Has Reached the Top of Mount Everest, Thinning Its Highest Glacier

Photo, posted October 27, 2011, courtesy of Goran Hogland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

An Arctic Bus | Earth Wise

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People have built vehicles for all sorts of extreme environments.  There are deep-sea exploration vessels and there have been lunar and Mars rovers.  But one thing that hasn’t existed so far are buses to transport groups of people around in extreme conditions in the Arctic.  Engineers at two Russian Universities are developing a passenger bus for riding in the Far North.   The project is being funded by the Russian Federation Ministry of Science and Higher Education and the URAL Automobile Manufacturing Plant.

The requirements for the vehicle are daunting.  The bus must be operable at extreme temperatures – 60 below zero Fahrenheit and lower – and have no difficulties even in challenging off-road conditions.

Current Arctic crew buses are not capable of getting through snow blockages and the all-terrain tracked vehicles that can get through them do not have sufficient passenger capacity. In addition to being able to go through snowbanks, the bus should be able to float on water for an hour.

Apart from its ability to withstand harsh Arctic conditions, the bus will also have a quarters module.  This means that it will have an autonomous life-support system for passengers in case of emergency.  The quarters module will be designed to sustain up to 20 people for up to 24 hours.  The module might also be used to hold medical equipment, thereby enabling practitioners to reach remote settlements and treat patients. 

The first tests of prototypes for the bus will be conducted in the near future.  The project aims to have the new Arctic Bus design complete and ready for manufacture by the end of 2023 and it will go into production in 2024.

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“Arctic Bus” Being Readied to Be Tested in the Far North

Photo, posted April 21, 2017, courtesy of Markus Trienke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Hurricanes In The Northeast | Earth Wise

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According to a new study led by Yale University, more hurricanes are likely to hit Connecticut and the northeastern U.S. as global warming continues to increase temperatures in the region.

Hurricane Henri made landfall in August as a tropical storm on the Connecticut/Rhode Island border.  In September 2020, subtropical storm Alpha made landfall in Portugal, the first subtropical or tropical cyclone ever observed to make landfall in the mainland of that country.

Tropical cyclones, hurricanes, and typhoons are typically intense and destructive in the lower latitudes. 

The study concludes that violent storms could migrate northward in our hemisphere and southward in the southern hemisphere as a result of warming caused by greenhouse gas emissions.

The research predicts that tropical cyclones will likely occur over a wider range of latitudes than has been the case on Earth for the last 3 million years.

In Connecticut, Hurricane Henri was not the only tropical storm to affect the region in 2021.  The remnants of Hurricane Ida brought damaging winds and torrential rain that felled trees and flooded streets and basements.

The northern expansion of such violent storms is going on as water levels in the Atlantic Ocean and Long Island Sound keep rising.  Because of melting glaciers thousands of miles away, water levels in Long Island Sound could rise by as much as 20 inches by 2050, enough to submerge parts of Groton’s shore and cause regular flooding in roads and neighborhoods.

Future hurricane prediction is an inexact science, but the ongoing trends do not bode well for the region.

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More hurricanes likely to slam Connecticut and region due to climate change, says study

Photo, posted October 29, 2012, courtesy of Rachel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Disease in Cavendish Bananas | Earth Wise

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Cavendish bananas account for about half of global banana production and the vast majority of bananas entering international trade.  The plant is unable to reproduce sexually and instead is propagated via identical clones.  So, the genetic diversity of the Cavendish banana is exceedingly low. 

In 2008, Cavendish cultivars in Sumatra and Malaysia started to be attacked by Panama disease, a wilting disease caused by a fungus.  In 2019, Panama disease was discovered on banana farms in the coastal Caribbean region, its first occurrence in the Americas.  In the 1950s, Panama disease wiped out the Gros Michel banana, the commercial predecessor of the Cavendish.

Scientists at the University of Cambridge have found a novel way to combine two species of grass-like plants – which include bananas, rice, and wheat – using embryonic tissue from their seeds.  The technique allows beneficial characteristics, such as disease resistance, to be added to the plants.

Joining the shoot of one plant to the root of another to grow as one plant is known as grafting.  It was thought to be impossible to do with grass-like plants – called monocotyledonous  grasses – because they lack a certain tissue type in their stems.  But the new research, published in the journal Nature, showed it can be done with the plants in their earliest embryonic stages.

Cavendish bananas are sterile, so disease resistance can’t be bred into future generations.  But the grafting technique may provide a way to produce Cavendish banana plants that are resistant to Panama disease.  It may be possible to save an important food crop before it is too late.

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New grafting technique could combat the disease threatening Cavendish bananas

Photo, posted July 1, 2015, courtesy of Augustus Binu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How Quickly Can The Planet Recover? | Earth Wise

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Climate change refers to long-term shifts in temperatures and weather patterns.  Historically, these shifts were natural.  But since the Industrial Revolution, scientists have found that the main driver of climate change has been human activities, primarily by adding significant amounts of greenhouse gases into the atmosphere through the burning of fossil fuels. 

Today, climate change is destabilizing Earth’s temperature equilibrium and is having a widespread impact on humans, animals, and the environment.  Some of the consequences of anthropogenic climate change include warmer air and ocean temperatures, shrinking glaciers, increasing spread of pests and pathogens, declining biodiversity, and more intense and frequent extreme weather events. 

But how quickly can the climate recover from the warming caused by an increase in carbon dioxide in the atmosphere? 

Researchers from Johannes Gutenberg-University Mainz in Germany looked into this question by investigating the significant rise in global temperatures that took place 56 million years ago.  Likely triggered by a volcanic eruption,  the increase of between 5 and 8 degrees Celsius was the fastest natural period of global warming that has impacted the climate. 

Because higher temperatures cause rocks to weather faster, the research team decided to analyze the weathering processes that occurred during the warming event 56 million years ago.  Their findings, which were recently published in the Journal Science Advances, indicate that the climate took between 20,000 and 50,000 years to stabilize following the rise in global temperatures.

Climate change is not some distant problem.  It is happening now and it poses a serious threat to all forms of life.  We need to address the problem with more urgency. 

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How quickly does the climate recover?

Photo, posted August 27, 2017, courtesy of Lt. Zachary West (100th MPAD) / Texas Military Department via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Pollution And The Galapagos Islands | Earth Wise

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The proliferation of plastics remains one of the world’s most challenging environmental problems.  Plastic pollution can be found in some of the most remote regions of the planet, including atop the world’s tallest mountains and in the deepest depths of the ocean.  Even the Galapagos Islands, a volcanic archipelago in the Pacific Ocean, are no exception.

According to a new study by researchers from the University of Exeter, the Galapagos Conservation Trust, and the Galapagos Science Center, plastic pollution has been found in seawater, on beaches, and inside marine animals at the Galapagos Islands. 

In the most polluted hotspots, more than 400 plastic particles were found per square metre of beach. The researchers found that only 2% of macroplastic pollution – plastic fragments larger than five millimeters – was identified as coming from the Galapagos islands. All seven of the marine invertebrate species examined – 52% of individuals tested – were found to contain microplastics.

Significant accumulations of plastic were also found in key habitats, including rocky lava shores and mangroves. In fact, plastics were found in all marine habitats at the island of San Cristobal, which is where Charles Darwin first landed in Galapagos.

Most of the plastic pollution in the Galapagos appears to arrive via ocean currents. According  to the research team, the highest levels of plastic pollution were found on east-facing beaches, which are exposed to pollution carried across the ocean on the Humboldt Current. 

The pristine images of the Galapagos, a world-famous biodiversity haven, might give the impression that the region is protected from plastic pollution.  But clearly that is not the case.

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Plastic in Galapagos seawater, beaches and animals

Photo, posted April 12, 2012, courtesy of Ben Tavener via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Surviving Climate Change | Earth Wise

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The sixth mass extinction of wildlife on Earth is happening now.  According to an analysis published last year in the journal Proceedings of the National Academy of Sciences, more than 500 species of land animals are on the brink of extinction and are likely to be lost within the next 20 years. Without the impact of humans, this quantity of extinctions would have taken thousands of years. 

Anthropogenic climate change continues to exacerbate problems that drive species to the brink.  Which species will be able to adapt and survive?

Using genome sequencing, a research team from McGill University in Montreal has found that some fish, like the threespine stickleback, can adapt very rapidly to extreme seasonal changes. Known for their different shapes, sizes, and behaviors, stickleback fish can live in both saltwater and freshwater, and can tolerate a wide range of temperatures.

Stickleback fish, which can be found in different estuaries along coastal California, provided researchers with an opportunity to study natural selection in real-time.  The researchers analyzed six populations of threespine stickleback fish before and after seasonal changes to their environment.   The research team discovered evidence of genetic changes driven by the seasonal shifts in habitat that mirrored the differences found between long-established freshwater and saltwater populations.  Since these genetic changes occurred in independent populations over a single season, the study highlights just how quickly the effects of natural selection can be detected. 

These findings suggest that scientists may be able to use the genetic differences that evolved in the past as a way to predict how species may adapt to climate change in the future.

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Which animals will survive climate change?

Sixth Mass Extinction of Wildlife Accelerating- Study

Photo, posted August 3, 2015, courtesy of Jason Ching/University of Washington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Forests And Climate Change | Earth Wise

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A carbon sink is anything that absorbs more carbon from the atmosphere than it releases.  Examples of carbon sinks include the ocean, soil, and plants.  In contrast, a carbon source is anything that releases more carbon into the atmosphere than it absorbs.  Volcanic eruptions and burning fossil fuels are two examples.

Forests are among the most important carbon sinks.  Trees remove carbon from the air and store it in their trunks, branches, and leaves, and transfer some of it into the soil.  But in many regions, deforestation, forest degradation, and the impacts of climate change are weakening these carbon sinks. As a result, some climate activists advocate for large-scale tree-planting campaigns as a way to remove heat-trapping CO2 from the atmosphere and help mitigate climate change. 

But according to a new study recently published in the journal Science, planting new trees as a substitute for the direct reduction of greenhouse gas emissions could be a pipe dream.  While planting trees is easy, inexpensive, and can help slow climate warming, the ongoing warming would be simultaneously causing the loss of other trees.  Instead, the research team says it makes more sense to focus on keeping existing forests healthy so they can continue to act as carbon sinks, and to reduce emissions as much as possible and as quickly as possible.        

But keeping forests healthy will require a paradigm shift in forest management.  Instead of trying to maintain forests as they were in the 20th century, the research team says forests need to be managed proactively for the changes that can be anticipated. 

One thing is clear: We cannot plant our way out of the climate crisis.

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Forests and climate change: ‘We can’t plant our way out of the climate crisis’

Photo, posted August 9, 2015, courtesy of Nicholas A. Tonelli 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...)