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New Orleans is sinking

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As climate change accelerates, rising sea levels are putting coastal communities at greater risk of flooding and storm surge. Driven by melting glaciers and warming oceans, global sea levels are rising at an increasing rate. For low-lying cities like New Orleans, even small increases can have serious consequences. And that risk is compounded by another factor: the land itself is sinking.

Much of New Orleans already sits at or below sea level, and parts of the city and its surrounding wetlands are gradually sinking. While most of the city remains stable, a new study by researchers from Tulane University suggests that sections of the region’s $15 billion post-Katrina flood protection system may require ongoing upgrades to keep pace with long-term subsidence.

The study, recently published in the journal Science Advances, used satellite data to track changes in ground elevation across Greater New Orleans between 2002-2020.  The researchers found that some areas – including neighborhoods, wetlands, and even concrete floodwalls – are sinking by more than an inch each year. In some spots, the land is dropping by nearly two inches annually.

Alarmingly, some of the concrete floodwalls and levees built to protect the city after Hurricane Katrina are themselves sinking. In a few cases, they are losing elevation faster than sea levels are rising, reducing their capacity to block storm surges.

The study highlights how satellite monitoring can play a critical role in guiding infrastructure maintenance and urban planning – not just in New Orleans – but in vulnerable coastal cities around the world.

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Vertical land motion in Greater New Orleans: Insights into underlying drivers and impact to flood protection infrastructure

Photo, posted September 22, 2010, courtesy of U.S. Army Corps of Engineers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rainforests and thunderstorms

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

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio

Can birds outfly climate change?

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As global temperatures continue to rise and ecosystems shift, animals are left with limited options. They must either adjust to the changing conditions in their habitats or relocate to cooler environments. For many species, neither choice is easy – or sometimes even possible.

Ecologists had long assumed birds were among the most adaptable species in a warming world simply because they can fly to higher altitudes or towards global poles. But a new study by researchers from Yale University found that even birds are struggling to stay ahead of rising global temperatures.

The study, which was recently published in the journal Nature Ecology and Evolution, analyzed 20 years of data from 406 bird species across North America. They found that while most birds did shift their ranges northward – by about 40 to 50 miles on average during the summer – the changes weren’t enough to keep up with the rapid pace of climate change.

Birds still experienced significant warming in their new areas when compared with temperatures in their original home range.  In fact, warming was about 1.35 degrees Celsius more in summer, and a striking 3.7 degrees more in winter. And some species, especially those with limited flight ranges or specific habitat needs, like the cactus wren, didn’t move at all.

Highly mobile birds like the blue-winged warbler did better, avoiding nearly two degrees of warming by traveling more than 100 miles north. But even they couldn’t completely dodge the heat.

The findings raise serious concerns about whether less mobile species can survive in a warming world, and underscores the urgent need to better understand and manage those most vulnerable to climate-driven extinction.

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Even birds can’t outfly climate change

Photo, posted March 1, 2023, courtesy of Henry via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The coastal squeeze

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Globally, coastal areas are being squeezed between rising seas on one side and human development on the other.  The average distance from the high waterline to the first built-up area with human structures or paved roads is less than 400 yards around the world.  The narrower a coast, the sooner rising sea levels cause problems.

Narrow coasts have reduced ability to defend against storm surges and other weather events.  Construction close to the sea makes coastal areas extra vulnerable.  Narrow coasts are also bad news for biodiversity.  A study by the Royal Netherlands Institute for Sea Research investigated plant diversity in both the Netherlands and the United States.  They found that the wider the coast was, the greater the plant diversity.

In Florida and Georgia, whenever coastal zones reached a couple of kilometers in width, diversity increased rapidly.  In the Netherlands, only coastal areas at least 3.8 kilometers wide reached their maximum plant diversity, but such areas are rare.  Dutch sand dune areas are typically no more than a kilometer wide, leaving plant diversity at no more than half the possible level.

Limited biodiversity in narrow coastal strips can be somewhat boosted by nature management but would benefit much more by spatial planning.  In the Netherlands, a spot called The Sand Motor is where a gigantic amount of sand was deposited off the coast in 2011.  Since then, natural forces have spread it along the coast.  Such coastal expansion could increase biodiversity.  Biodiversity is not a luxury.  It makes for a better future for coastal defense, a healthy drinking water supply, and a better human food supply.

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Coastal squeeze is bad for biodiversity, and for us!

Photo, posted June 21, 2017, courtesy of Mark Bias via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Living in a warming world

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As global temperatures rise due to increased greenhouse gas emissions, communities around the world face more frequent and intense heatwaves, droughts, and extreme weather events. These growing climate pressures not only strain infrastructure and natural resources, but also play a critical role in shaping where people live. 

Recent projections from the First Street Foundation, which analyzes climate risks across the United States, highlight just how significant these shifts could be. In Sacramento County, California, rising flood risks, declining air quality, and soaring insurance costs could lead to a population decline of up to 28% by 2055. The risk assessment also projects that Monmouth and Ocean counties in New Jersey could each lose more than 30% of their populations. And Fresno County, California, could see nearly half of its residents relocate due to mounting climate-related pressures.

Urban areas like cities, towns, and suburbs are particularly vulnerable to the impacts of climate change.  Cities become significantly hotter due to the abundance of heat-absorbing surfaces and lack of green spaces, which intensifies heatwaves, worsens conditions for vulnerable populations, and may ultimately force some people to move.

Addressing these challenges requires a combination of climate solutions focused on both mitigation and adaptation. Solutions like expanding green infrastructure with urban parks and green roofs, and promoting sustainable development through energy-efficient buildings and transit-friendly design could all play a vital role in strengthening climate resilience.

As the planet warms, where we live – and how we live there – is rapidly being redefined.

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The 12th National Risk Assessment

Solar on farmland

Photo, posted May 15, 2013, courtesy of Germán Poo-Caamaño via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Amphibians and climate change

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Amphibians are a group of vertebrate animals that include frogs, toads, and salamanders. They are unique for their ability to live both in water and on land during different stages of life. Amphibians play a crucial role in ecosystems, often serving as both predators and prey in food webs.

Amphibians are the world’s most at-risk vertebrates, with more than 40% of species listed as threatened.  They are cold-blooded creatures and rely on external sources to regulate their body temperature.  But needing to regulate their body heat this way makes amphibians particularly vulnerable to temperature change in their habitats. 

Researchers from the University of New South Wales in Australia can now predict the heat tolerance of 60% of the world’s amphibian species.  This new tool will allow scientists to better identify which amphibian species and habitats will be most impacted by climate change.  

The study’s landmark findings, which were recently published in the journal Nature, found that 2% of amphibian species are already exposed to overheating in shaded terrestrial conditions.  According to the research team, a 4°C global temperature increase could push 7.5% of amphibian species beyond their physiological limits. 

Local amphibian extinctions can trigger ecological repercussions, including reshuffling community compositions, eroding genetic diversity, and impacting the food chain and overall ecosystem health.

The researchers highlight the importance of vegetation and water bodies in protecting amphibians during heat waves, and emphasize the need to provide adequate water and shade during future conservation efforts. 

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The pot is already boiling for 2% of the world’s amphibians: new study

Photo, posted October 8, 2011, courtesy of Dave Huth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megadroughts

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A new study by Swiss and Austrian scientists has found that persistent multi-year droughts have become increasingly common since 1980 and will continue to proliferate as the climate warms.

There are multiple examples in recent years in places ranging from California to Mongolia to Australia.  Fifteen years of persistent megadrought in Chile have nearly dried out the country’s water reserves and even affected Chile’s vital mining output.  These multi-year droughts have triggered acute water crises in vulnerable regions around the world.

Droughts tend to only be noticed when they damage agriculture or visibly affect forests.  An issue explored by the new study is whether megadroughts can be consistently identified and their impact on ecosystems understood.

The researchers analyzed global meteorological data and modeled droughts over a forty-year period beginning in 1980.  They found that multi-year droughts have become longer, more frequent, and more extreme, covering more land.  Every year since 1980, drought-stricken areas have spread by an additional fifty thousand square kilometers on average, an area the size of Vermont and New Hampshire combined. 

The trend of intensifying megadroughts is clearly leading to drier and browner ecosystems.  Tropical forests can offset the effects of drought as long as they have enough water reserves.  However, the long-term effects on the planet and its ecosystems remain largely unknown.  Ultimately, long-term extreme water shortages will result in trees in tropical and boreal regions dying, causing long-term and possibly irreversible damage to these ecosystems.

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The Megadroughts Are upon Us

Photo, posted January 7, 2018, courtesy of Kathleen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and orchard health

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The frequent and massive megafires in places like Canada and the American west have led to a lot of research on the impact of smoke on humans but there has been less study of the effects of smoke on plant health.  Researchers at the University of California, Davis have found that trees are just as vulnerable as humans are to the harmful effects of long-term exposure to smoke.

The Davis researchers studied almond, pistachio, and walnut trees at 467 orchard sites in California’s Central Valley from 2018 to 2022.  In 2022, so-called megafires burned more than 4.2 million acres in California, pouring ash and smoke into the sky.  The researchers had been studying how trees store carbohydrates to cope with heat and drought. 

With the onset of the fires, they saw an opportunity to study how smoke affects carbohydrate levels.  Trees use stored carbohydrates to sustain them through winter dormancy and spring growth.  Trees produce carbohydrates via photosynthesis and thick smoke blocks the amount of light reaching the trees.  Beyond that, there are other aspects of wildfire smoke, such as particulate matter and ozone that appear to affect photosynthesis.

The team found that the smoke not only reduced the amount of carbohydrates in trees but also caused losses that continued even after the fires were extinguished.  This led to nut yield decreases of 15% up to 50% in some orchards.  The researchers expected to see some impact on the trees during periods when smoke was really dense but were not expecting the smoke to have such a lingering effect and result in a significant drop in yield.

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Smoke From Megafires Puts Orchard Trees at Risk

Photo, posted October 1, 2008, courtesy of Suzi Rosenberg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Weather extremes for most people

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Scientists from the CICERO Center for International Climate Research in Norway along with researchers at the University of Reading in the UK have analyzed how global warming can combine with normal variations in the weather to produce decades-long periods of very rapid changes involving both extreme temperatures and extreme amounts of rainfall.

Many parts of the world have already been experiencing record temperatures and extreme rainfall events.  Previously, most analyses of the changing climate have focused on the global mean and not on the impact of extreme weather on specific countries.

The study made use of large climate model simulations to show that if global emissions continue on the path they have been on, large parts of the tropics and subtropics – which are home to 70% of the world’s population – are expected to experience strong rates of change in temperature and precipitation extremes over the next 20 years.  But even if there is strong emissions mitigation – meaning that emissions are reduced enough to reach the goals of the Paris Climate Agreement – the expectation is that 20% of the world’s population will face extreme weather risks. 

These extreme events currently account for a disproportionate share of the realized impacts of climate change.  Heatwaves cause heat stress and excess mortality of both people and livestock.  Extreme precipitation leads to flooding, damage to settlements, infrastructure, crops, and ecosystems, as well as to reduced water quality. 

Society will be increasingly vulnerable to these extreme events, especially when multiple hazards occur at the same time.

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Extreme weather to strengthen rapidly over next two decades

Photo, posted May 20, 2024, courtesy of Dale Cruse via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The East Coast is sinking

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Most of the world’s largest cities are located in coastal regions and coastal regions are on the front lines of the climate crisis.  Human populations continue to migrate towards low-elevation coastal areas at the same time that sea level rise is accelerating.  Coastal communities worldwide are increasingly vulnerable to the dangers of flooding and erosion.  With these hazards occupying a great deal of attention, there has been less attention paid to the dangers of land subsidence.

A recent study by researchers at Virginia Tech and the US Geological Survey using satellite data shows that parts of America’s east coast are sinking, and the culprit is the withdrawal of too much water from the aquifers beneath these coastal areas.

A series of overlapping aquifers extends all the way from New Jersey to Florida along the coast, providing a reliable source of water for drinking, irrigation, and industrial uses.  Even though these areas get regular rainfall, the deeper aquifers can take hundreds or even thousands of years to refill once water is pumped out.  Once water is removed, soils can compress and collapse, causing the land surface to sink.

Cities that were built on drained marshland or on fill soil are especially vulnerable to compaction. 

Seal level rise is slow, but it is insidious and continuous.  Add land subsidence to the mix and effects multiply.  Places like Boston, New York, Washington DC, Roanoke, Savannah, Jacksonville, and Miami, among others, all are increasingly vulnerable to these coastal hazards.  The combined effects of sea level rise and subsidence may even triple the prospects for flooding areas over the next few decades.

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As Aquifers Are Depleted, Areas Along The East Coast Of The US Are Sinking

Photo, posted August 7, 2015, courtesy of Tracy Robillard / NRCS Oregon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Elephants and protected areas

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Standing up to 13 feet tall and weighing up to 7 tons, African savanna elephants are the largest species of elephant and the biggest terrestrial animal on Earth.  According to the World Wildlife Fund, African savanna elephants can be found in 23 countries and live in a variety of habitats, including savannas, forests, and deserts.  The largest populations are in Southern and Eastern African countries.

According to assessments from the International Union for Conservation of Nature, the population of African savanna elephants has decreased by at least 60% over the last 50 years.  Poaching and habitat loss are the two main drivers of the population decline.  In 2021, the status of the African savanna elephant was changed from vulnerable to endangered on the IUCN’s Red List of Threatened Species. 

However, according to a new study recently published in the journal Science Advances, conservation measures have successfully stopped African savanna elephant population declines across southern Africa.  The international team of researchers found that the pattern varies regionally, with some elephant populations soaring while others are still facing large declines.

Overall, the study found that there are the same number of elephants now as there were 25 years ago. According to researchers, the key to long-term elephant population growth and sustainability isn’t where a protected area is, but rather how connected it is to other protected or neutral areas around it. 

This isn’t a new concept; in fact, many parks have been connected to one another.  But this study helps prove that the method is effective for elephant conservation.  

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Protected Areas for Elephants Work Best if They Are Connected

African elephant species now Endangered and Critically Endangered – IUCN Red List

African savanna elephant

Photo, posted October 20, 2018, courtesy of Ray via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Thousands of species threatened

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The International Union for the Conservation of Nature is an organization working in the field of nature conservation and sustainable use of natural resources.  The IUCN has been around for nearly 75 years and is the global authority on the status of the natural world and the measures needed to safeguard it.

In its latest accounting, the IUCN has determined that more than 44,000 species worldwide are threatened with extinction.  Among them, nearly 7,000 face an immediate threat from climate change.

The organization tracks 157,000 species to compile its Red List and found that climate change poses a growing threat to many kinds of wildlife. At particular risk are freshwater fish including Atlantic salmon, which are now classified as “Near Threatened.” 

In all, about 25% of freshwater fish are threatened with extinction.  This is in part driven by rising sea levels which causes saltwater to be driven up into rivers.  Some 41% of amphibians are threatened with extinction, in part due to more intense heat and drought.  Many populations of green turtles are at risk of extinction because of rising temperatures lowering hatch rates and rising sea levels flooding nests.

It isn’t just animals at risk.  For example, big leaf mahogany, one of the world’s most commercially sought-after timber trees, has moved from Vulnerable to Endangered on IUCN’s Red List.  Thousands of trees have been added to the Red List, many of which are timber species, and some are keystone species in forests.

Endangered and threatened species are often irreplaceable parts of ecosystems which provide humans with many services that only the natural world can.

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More Than 44,000 Species Now Threatened With Extinction

Photo, posted November 22, 2010, courtesy of E. Peter Steenstra/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic In Lakes | Earth Wise

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We are always talking about the millions of tons of waste plastic that finds its way into the oceans and about the challenges of trying to remove it.  A new multinational study has found that the concentration of plastics and microplastics in some lakes is even worse than in the so-called garbage patches in the oceans and some of these lakes are even in remote places around the world

Scientists from institutes in multiple countries collected water samples from 38 lakes and reservoirs in 23 countries across six continents.  The samples were then all analyzed by the University of Milan to assess the presence of plastic particles more than a quarter millimeter in size.

The study found that two types of lakes are particularly vulnerable to plastic contamination:  lakes and reservoirs in densely populated and urbanized areas and large lakes with elevated deposition areas, long water-retention times, and high levels of human influence.

Lakes found to have the highest concentration of plastic included some of the main sources of drinking water for communities and were also important to local economies.  These included Lough Neagh in Northern Ireland, Lake Maggiore in Italy, and Lake Tahoe on the California/Nevada border.  Not all the lakes studied contained large amounts of plastic.  For example, Windermere, the largest lake in England, had very low concentrations of plastic in surface water.

This was the first global survey of the abundance and type of plastic pollution in lakes and reservoirs and the scale of freshwater plastic pollution is sobering indeed.  There is widespread concern that plastic debris is having harmful effects on aquatic species and ecosystem function and clearly is not limited to marine ecosystems.

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Plastic pollution is higher in some lakes than oceans

Photo, posted May 27, 2019, courtesy of Jonathan Cook-Fisher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air Pollution In The Arctic | Earth Wise                     

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Climate change is shrinking the Arctic ice cover, which is making it easier for ships to travel along the northern coast of Russia, known as the Northern Sea Route or the Northeast Passage.  There is also the Northwest Passage, which connects the Atlantic and Pacific Oceans via waterways through the Canadian Arctic Archipelago.

More than 600 fishing vessels sail the waters of the Arctic Ocean, but these fishing vessels are not the worst offenders when it comes to the growing problem of air pollution.  Giant natural gas tankers are becoming a much bigger problem.

In 2021, only 26 natural gas tankers traveled through Arctic waters.  But these ships can be 1000 feet long or more and produce far more CO2 emissions than fishing boats.   In 2019, the tankers accounted for 28% of the emissions and the number of them cruising the Arctic has been growing.

As the ice cover in the Arctic continues to shrink, more and more ships of all varieties, including cruise ships, fishing vessels, as well as tankers, are coming north and spending more time in the Arctic.  Any increases in ship traffic will increase the pollutant load in the Arctic and the Arctic is one of the most vulnerable environments in the world.

Between 2013 and 2019, the aggregated nautical miles that vessels traveled in what is called the Polar Code area increased by 75%. It isn’t just that more ships like tankers are going there.  It is that their operational season is expanding.

Air pollution isn’t the only problem.  Shipping in the Arctic brings with it light pollution, noise, marine litter, and more.  Only zero activity has zero pollution.

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The worst polluters in the Arctic are not what you think

Photo, posted February 26, 2015, courtesy of Chris Parker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Corals Saving Corals | Earth Wise

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A new study by researchers at the University of California, Davis, has found that under the right circumstances, disease-resistant corals can rescue corals that are more vulnerable to disease.

The researchers monitored a disease outbreak at a coral nursery in the Cayman Islands.  They tracked the presence of disease in 650 coral fragments in various arrangements over a period of five months.  They found that some corals are more resistant to disease just by being around other corals that are particularly resistant.  In general, when there are only corals of the same genetic makeup, they are more vulnerable to disease than corals that grow among a mixture of genotypes.  But beyond that, some vulnerable corals become more resistant to disease just by being around other corals that are particularly resistant.  Proximity to the resistant genotypes helped to protect the susceptible corals from the effects of disease.

These findings provide new evidence that genetic diversity can help reduce disease transmission among corals and furthermore, it is important to consider how corals are arranged in coral nurseries or in reef restoration projects.

The ability of resistant coral to help protect vulnerable individuals appears to be similar to how vaccinations work among humans.  Vaccinated individuals resist a disease, which effectively erects a barrier that weakens a disease’s ability to move through a population.

The researchers hope that the findings of this study will be integrated into coral nursery and reef restoration projects.  By intentionally arranging corals with mixtures of genotypes, it will help rebuild coral resilience and help those corals that are vulnerable to disease to thrive.

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Corals Saving Corals

Photo, posted December 30, 2014, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

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

The Snail Darter Is Safe | Earth Wise

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The snail darter is a three-inch-long snail-eating fish that was once only found in the Little Tennessee River.  When that river was going to be dammed by the Tellico Dam under construction in the 1970s, the snail darter was listed on the endangered species list and the little fish subsequently became the subject of a legal battle that made it all the way up to the U.S. Supreme Court.   With the dam project 95% complete in 1978, the Supreme Court blocked further construction, citing the Endangered Species Act.  A year later, Congress exempted the project from the requirements of the Act, thereby clearing the way for the completion of the dam.

In order to save the snail darter, biologists transplanted the fish into several other nearby rivers and waterways.  In addition, the Tennessee Valley Authority modified the operation of the Tellico Dam to release more oxygen-rich water downstream.  Beyond those measures, the river cleanup under the Clean Water Act further aided the fish’s recovery.

In 1984, the snail darter was removed from the endangered species list and was listed as threatened or vulnerable.  Recently, the U.S. Department of the Interior officially removed the snail darter from the federal list of threatened and endangered wildlife. 

The snail darter is the fifth fish species to be delisted because its population has recovered.  It is the first in the eastern United States.  With better management of water releases at dams, many other imperiled aquatic species could be recovered.

Overall, more than 50 plants and animals have recovered under federal protection, including American alligators, humpback whales, peregrine falcons, and bald eagles.

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Once at Center of Controversial Case, the Snail Darter Fish Is No Longer Threatened

Photo, posted July 22, 2015, courtesy of The U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Planting Millions Of Trees Isn’t So Easy | Earth Wise

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There are initiatives around the world to plant millions of trees as a way to fight climate change.  Unfortunately, scientists have observed that many of these projects are ill-conceived and poorly managed.  Some have failed to grow any forests at all.

One such project was an attempt to plant a million mangrove seedlings in coastal mud on the Filipino island of Luzon in 2012.  Ten years later, less than 2% of the trees have survived.  The other 98% have died or have washed away.  The problem was that the site of the project was ecologically unsuited to mangroves because it is too waterlogged and there is no oxygen available except in a few sheltered spots.

In 2019, the Turkish government managed the planting of 11 million trees in 2,000 sites across the country.  A later survey found that 90% had died, although the government denies that assertion.

Many other projects have also had dismal results.  The causes of failure vary but include planting single species of trees that become vulnerable to disease, competing demands for land, changing climate, planting in areas not previously forested, and lack of ongoing care for the saplings including watering them.

Nobody is opposed to mass tree planting.  There is no anti-tree lobby.  But tree planting is sometimes a form of greenwashing.  It is great for public relations but unless it is done properly with appropriate planning, it can be a waste of effort and money.  The result can be a phantom forest that does nothing for the climate.

Forest planting can work if the social and environmental conditions are right, and if planting is followed by long-term monitoring and care of the trees.

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Phantom Forests: Why Ambitious Tree Planting Projects Are Failing

Photo, posted April 20, 2016, courtesy of the U.S. Navy / Mass Communication Specialist 2nd Class John Benson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Some Good News For The Great Barrier Reef | Earth Wise

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It seems like there has been nothing but dire news from Australia’s Great Barrier Reef.  Earlier this year, there was yet another mass bleaching event – the fourth in seven years and the first ever to strike during a cooler La Niña phase in the Pacific.  But this bleaching event was less severe than other recent ones, which makes it possible for parts of the reef to bounce back.

In particular, in the northern and central stretches of the reef, scientists have recorded the most extensive coral cover seen in 36 years of study.  In areas where coral cover has expanded, it is mostly fast-growing Acropora corals driving the growth.  That isn’t the best outcome, given that Acropora are particularly vulnerable to strong waves, highly susceptible to bleaching, and are the preferred target of crown-of-thorns starfish.

Those creatures are a major problem for the Great Barrier Reef.  In contrast to the upper stretches of the reef, the southern third actually saw coral cover drop from 38 to 34 percent over the course of the past year.  Scientists blame the decline on an outbreak of crown-of-thorns starfish, which prey on corals.  The starfish grow faster and eat more in warmer, more acidic waters.   Carbon emissions are both raising ocean temperatures and turning waters more acidic.

The large increases in hard coral cover in the reef are certainly good news, but it is important to understand that they can be quickly negated by disturbance on reefs where Acropora corals predominate.  Warming temperatures and mass bleaching events continue to pose a critical threat to all reefs, especially when there are crown-of-thorns starfish outbreaks and increasing frequency of tropical cyclones.

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Parts of Great Barrier Reef See Most Extensive Coral Cover In 36 Years

Photo, posted July 15, 2019, courtesy of Kenneth Lu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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