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Sunscreen And Coral Reefs | Earth Wise

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The dangers of overexposure to UV solar radiation have led to the extensive production and use of sunscreen products.  It is generally understood that many of the chemical compounds used in sunscreen products have toxic effects on marine organisms, but research in this area is relatively limited.

There are estimates that as many as 82,000 kinds of chemicals from personal care products have made their way into the world’s oceans.  In 2015, it was estimated that around 14,000 tons of sunscreen are ending up in the world’s coral reefs per year and causing irreparable damage.

Eighty-five percent of the Caribbean’s coral reefs died before the turn of the century, not as a result of global warming, but because of pollution.  Oxybenzone and octinoxate are two of the common sunscreen ingredients that are most toxic to corals.  Preservatives like parabens are also toxic.

There are much safer sunscreens such as those based on zinc oxide or titanium oxide.  In some places, such eco-friendly sunscreens are mandatory.  Sunscreens with SPF values above 30 contain a higher percentage of chemicals and have been shown to not really provide any more protection than SPF 30 products.

Apart from the choice of sunscreen product, if one really wants to reduce the negative impact sunscreen has on reefs and marine life, wearing sun-protective clothing such as rash-guards will allow the use of much less sunscreen and therefore result in less of it entering the ocean.

Products that can help protect against the harmful effects of UV radiation on human health are extremely important, but it is also important to identify and quantify the risks associated with these products to reef ecosystems.

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How to Know If Your Sunscreen Is Killing Coral Reefs — and the Brands to Try Instead

Impacts of sunscreen on coral reefs needs urgent attention, say scientists

Photo, posted January 11, 2015, courtesy of Elch Korallen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas And Wastewater Leakage | Earth Wise

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Global mean sea level has risen nearly 9 inches since 1880, with over two inches of that over just the last 25 years.  The rising water level is primarily due to two factors:  additional water in the oceans coming from melting glaciers and ice sheets; and the thermal expansion of seawater as it warms.  Climate models estimate that over the course of the century, global sea levels will rise at least a foot even if efforts to reduce greenhouse gas emissions are quite successful and, in the worst case, levels could rise as much as 8 feet.

Faced with this situation, the greatest concerns are, initially, increasing amounts of coastal flooding and erosion and, as things get worse, inundation of coastal regions making many places uninhabitable and creating millions of climate refugees.

Recently, computer modeling studies have focused on an additional imminent problem:  the flooding of coastal wastewater infrastructure, which includes sewer lines and cesspools.

A new study by the University of Hawaii at Manoa is the first to provide direct evidence that tidally driven groundwater inundation of wastewater infrastructure is already occurring in urban Honolulu.  The study shows that higher ocean water levels are leading to wastewater entering storm drains and the coastal ocean.  The result is degradation of coastal water quality and ecological health.

The researchers used chemical tracers to detect groundwater discharge and wastewater present at multiple low-lying areas during spring tides.  During high tides, storm drains become channels for untreated wastewater to flood streets and sidewalks. 

People tend to think of sea-level rise as a future problem, but there are already serious effects going on today that are only going to get worse.

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Sea-level rise drives wastewater leakage to coastal waters

Photo, posted August 23, 2011, courtesy of Eric Tessmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Helping Corals With Beneficial Bacteria | Earth Wise

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A group of researchers at the King Abdullah University of Science and Technology in Saudi Arabia is exploring a novel technology to improve the health of corals.  Around the globe, corals are being stressed by pathogens, toxins, and warming waters leading to widespread bleaching events.

The new idea is to introduce beneficial bacteria to the corals, thereby boosting the strength and resilience of their symbiotic partners.  The concept is akin to the use of probiotics in plant science.  Corals rely on bacterial and algal symbionts to provide nutrients, energy (through photosynthesis), toxin regulation, and protection against pathogens.  

The researchers selected bacteria that are naturally symbiotic to specific coral species on reefs in the Red Sea, ensuring that no alien bacteria are accidentally introduced.  A probiotic cocktail comprising six bacteria strains was used in a laboratory setting.  Results in the lab have been promising so far, as they have observed dynamic and metabolic alterations to the corals that boosted their chances of survival under heat stress. 

Success in the lab will need to be translated to success in the open oceans, which is challenging.  Scaling up and seeding whole reefs might involve robots and artificial intelligence in order to deliver probiotics either into sediments or directly onto corals.

The use of beneficial microorganisms is not the solution to the global destruction of coral reefs.  Only worldwide CO2 mitigation can ultimately accomplish that.  But the probiotic approach might buy corals some time as they deal with shifting environmental pressures and try to adapt to a changing world.

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Microbiome boost may help corals resist bleaching

Photo, posted March 18, 2018, courtesy of Steven dos Remedios via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Living On Trash | Earth Wise

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Litter is persistent and widespread in rivers worldwide.  The world’s major rivers and estuaries are hotspots for plastic waste.  Trash and microparticles wash down tributaries and build up before rivers enter oceans.

New research published in the journal Freshwater Biology has found that as this waste accumulates, aquatic river species like insects and snails are increasingly choosing to settle on plastic rather than on natural features like rocks and fallen branches.

Researchers from the University of Nottingham in the UK collected plastic waste from three rivers in eastern Britain along with rocks from the same rivers.  Their analysis of all the macroinvertebrates on the items’ surfaces found that the surfaces of plastic waste items had nearly four times the diversity of the small animals as did the rocks.  In addition, the more complex the plastic’s surface was, the higher the diversity.

The growing abundance of plastic waste coincides with a decline in natural habitat features in urban rivers.  This is a result of increasing amounts of sedimentation from development that blankets riverbeds in silt and sand, restricting the supply and movement of rocks, fallen tree branches, and aquatic plants.

Clearly litter can serve as a place for various species to colonize, but trash is not a good environment for them.  Trash can release toxic chemicals and entangle animals.  Microplastics pose risks for the animals if ingested.

Estimates are that between 1.15 and 2.41 million tons of plastic waste enter the ocean every year from rivers around the world.  Natural habitats have become rare in urban rivers.  River ecosystems built around piles of trash are not a good thing.

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As Plastic Pollution in Rivers Gets Worse, Species Are Increasingly Living on Litter

Photo, posted August 17, 2010, courtesy of Renee_McGurk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Warming Could Stabilize | Earth Wise

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The world has been heading toward climate disaster with the effects of greenhouse gas-induced warming looming larger and larger.  But recent analysis published in Nature Climate Change offers hope that rapidly eliminating emissions could stabilize global temperatures just within a couple of decades.

For quite some time, it has been assumed that further global warming would be locked in for generations regardless of the extent of emissions reductions going forward.  This conclusion was based on having a certain carbon dioxide concentration in the atmosphere which would linger for hundreds of years even if emissions were reduced.

Recent analysis takes into account the dynamism of the Earth’s natural systems which could actually reduce atmospheric CO2 content because of the huge carbon absorption capacity of oceans, wetlands, and forests.  The key requirement is to drastically reduce emissions so that these natural systems can take over.

More than 100 countries have pledged to get to net zero emissions by 2050.  That means they will emit no more carbon dioxide than is removed from the atmosphere by such actions as restoring forests.   The UK, Japan, and the European Union are among the countries that have set this zero target, and the United States is joining the club.

Climate models show that a global temperature rise of 2 degrees Celsius over that of the pre-industrial period would lead to global calamities that include punishing heatwaves, flooding, and mass displacement of people.  The world has already heated up by 1.1 degrees and governments have committed to restrain the rise to less than 1.5 degrees under the Paris Climate Agreement.

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Global Warming Could Stabilize Faster than Originally Thought If Nations Achieve Net Zero

Photo, posted September 10, 2017, courtesy of Ron Cogswell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Costs Of Mislabeled Seafood | Earth Wise

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Seafood is the world’s most highly traded food commodity and reports of seafood mislabeling have become increasingly common over time.  A new study by Arizona State University looked at the environmental effects of mislabeled seafood.

What is mislabeled seafood?  Sometimes the snapper you were served was really Pacific Ocean Perch.  Maybe grouper was really whitefin weakfish.  Many times white leg shrimp are actually giant tiger prawns.

Approximately 190,000 to 250,000 tons of mislabeled seafood are sold in the U.S. each year, or 3.4 to 4.3% of consumed seafood.  Previous studies focused on the economic aspects of getting cheaper fish when paying for more expensive fish.  The new research looks at the environmental costs associated with mislabeled seafood.

Substituted seafood is 28% more likely to be imported from other countries, which may have weaker environmental laws than the U.S.  In the United States, fishery management is pretty good.  There is strong monitoring and enforcement to support limits on fishing.  Metrics like fish abundance, fishing mortality, bycatch, and discards are all monitored.  In many other places, this is not the case.

To really evaluate the overall effects of seafood mislabeling, one has to take into account both the rates of substitution and the levels of consumption. 

Consuming fish from a well-managed fishery should not have a negative impact in terms of the population now or in the future.  But even inadvertently consuming fish from poorly managed fisheries in not sustainable.  It is good to get your seafood from a trusted source.

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ASU Study Looks At The Environmental Effects Of Purchasing, Consuming Mislabeled Fish

Photo, posted August 1, 2014, courtesy of Ralph Daily via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Warming And Sea Turtle Births | Earth Wise

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Climate change is a serious threat to species whose sex is determined by temperature.  Among these are sea turtles.  Whether marine turtles are born male or female turns out to depend on the temperature of their nest during incubation.

Sea turtle nests need to be around 84.6 degrees Fahrenheit on average to produce a 50:50 sex ratio for embryos developing in eggs.  If temperatures are higher, embryos predominantly become female.  There is a transitional range of temperatures over which both males and females are produced.  Below that range, only males are produced; above that range, only females are produced.

According to recent research published in the journal Conservation Science and Practice, sand temperatures along the Red Sea exceeded the 84.6-degree threshold in all but one of the sites studied.  Some sites measured nearly 96 degrees.  The Red Sea region is home to five of the world’s seven species of sea turtles, including endangered green turtles and critically endangered hawksbill turtles.

Skewing the sex distribution of a species is a serious threat to the future survival of the population.

The Red Sea findings are similar to observations around the world.  In Florida, sea turtle hatchlings were born 100% female in seven out the past 10 years, and in the other three years, males only made up 10-20% of the brood.  In Australia’s Raine Island, the largest green turtle nesting ground in the Pacific Ocean, the ratio of female to male turtle hatchlings in 2018 was 116:1.

Marine turtles have been around since the late Triassic period and have adapted to previous climate shifts.  But the rapid pace of human-driven climate change is threatening the future survival of these creatures.

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Rising Temperatures Driving a Shift to All-Female Sea Turtle Populations

Photo, posted in October, 2005, courtesy of Frank_am_Main via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Even The Deep Sea Is Warming | Earth Wise

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Approximately 75% of the area covered by ocean is deep, dark, and cold.  This is known as the deep sea.  But even in these remote regions of the planet things are heating up. 

According to a new study published in the journal Geophysical Research Letters, researchers analyzed a decade of hourly temperature readings at four depths in the Atlantic Ocean’s Argentine Basin, off the coast of Uruguay.  The research team selected recording depths that would best represent the average depth of the ocean, which is just over 12,000 feet. 

The researchers found that deep sea temperatures fluctuate more than was previously known.  They also detected a warming trend at the bottom of the ocean.  In fact, all recordings indicated a warming trend of 0.02 to 0.04 degrees Celsius per decade between 2009 and 2019.  This is a significant warming trend in the deep sea because temperature fluctuations are typically measured in thousandths of a degree. 

Researchers say this increase is consistent with warming trends in the shallow ocean associated with anthropogenic climate change.  However, they say more research is needed to better understand what is driving the warming temperatures in the deep sea. 

A better understanding of what is driving these changes could have far-reaching implications.  Since oceans absorb a significant amount of the world’s heat, learning about the oceans’ temperature trends could help researchers better understand temperature fluctuations in the atmosphere as well.

The researchers hope their findings will demonstrate the need to survey deep ocean temperatures annually in order to better identify the long-term trends. 

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The deep sea is slowly warming

Photo, posted July 1, 2018, courtesy of NOAA Ocean Exploration and Research via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hottest September | Earth Wise

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Here’s a news item that is like many other recent news items:  September 2020 was the hottest September since 1880, according to the National Oceanic and Atmospheric Administration.   The warm September is a part of a year that so far is poised to be at least the second hottest year in the 141-year climate record.

The ten warmest Septembers on record have all occurred since 2005, and the seven warmest Septembers have occurred in the past seven years.

So far, the year-to-date average global temperature has been the second warmest on record, being just 0.07 degrees Fahrenheit lower than the record year-to-date temperature set in 2016.  Expectations are that 2020 will end up somewhere among the three warmest years on record for the globe.

September was warm in many places around the world.  California and Oregon had their warmest September ever.  Europe had its warmest September on record, Asia had its second warmest September on record as did Australia and South America. 

So far, it has been the hottest year-to-date on record in Europe, Asia, and the Gulf of Mexico.  No land or ocean areas anywhere had record-cold year-to-date temperatures. 

Global temperatures represent an average over the entire surface of the planet.  The fact that the global temperature is now nearly one Celsius degree above the 20th century average means that a vast amount of heat has been added in order to warm all the oceans, atmosphere, and land by that much.  So, every uptick in global temperature is a big deal.

Meanwhile, the average Arctic sea ice coverage for September was the second smallest on record.  The 14 smallest minimum annual sea ice extents have all occurred in the past 14 years.

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Earth just had its hottest September on record

Photo, posted September 2, 2020, courtesy of Tim Vrtiska via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shrinking Ice In The Bering Sea | Earth Wise

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The Bering Sea forms the divide between the two largest landmasses on Earth:  Eurasia and the Americas.  Recent analysis of vegetation from a Bering Sea island has determined that the extent of sea ice in the region is the lowest it has been for over 5,000 years.

St. Matthew Island, a small island in the middle of the Bering Sea, has essentially been recording what is happening in the ocean and atmosphere around it, in the form of the composition of peat layers on the island.  By analyzing the chemical composition of peat core samples, scientists can estimate how sea ice in the region has changed over the course of time.

Changes in the relative amounts of two oxygen isotopes in the sediment and plant debris trapped in the peat on the island reflect the nature of precipitation during the period when the peat layers formed.  That ratio is correlated with the amount of sea ice in the region.  Satellite data acquired over the past 40 years confirms this correlation.

Analysis of the data shows that the current ice levels are unprecedented in the last 5,500 years.  These long-term findings affirm that reductions in Bering Sea ice are due to more than recent higher temperatures associated with global warming.  Atmospheric and ocean currents, which have also been altered by climate change, play a large role in the presence of sea ice.

Summertime sea ice in the Arctic was expected to reach its second-lowest extent in September in 40 years of observation.  Sea ice typically builds up again each winter, but the changes in ice extents actually lag behind changes in greenhouse gas level by decades.  Future ice loss is already built into the system.

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Bering Sea ice extent is at most reduced state in last 5,500 years

Photo, posted December 2, 2012, courtesy of Bering Land Bridge National Preserve via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sustainable Flip-Flops | Earth Wise

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Flip-flops are the world’s most popular shoe.  They are lightweight, comfortable, affordable, and durable.  In fact, the global market for flip-flops is expected to reach a whopping $23.8 billion by the year 2025. 

But the popularity comes with a price.  Flip-flops account for a troubling percentage of plastic waste that ends up in our landfills and oceans.  As a result, demand for alternatives is compelling researchers to develop more sustainable versions of the popular footwear.

Scientists at the University of California San Diego have spent years working on this issue, and recently announced a breakthrough.  According to a study recently published in Bioresource Technology Reports, the research team has formulated polyurethane foams – made from algae oil – to meet commercial specifications for mid-sole shoes and the foot-bed of flip-flops.   In other words, the scientists have created sustainable, biodegradable, and consumer-ready materials that could replace plastics in some footwear. 

The UC San Diego scientists collaborated with Algenesis Materials – a technology startup – on the research.  Together, they worked to not only create the shoes, but to degrade them as well.  The team tested their customized foams by immersing them in traditional compost and soil.  The algae-based materials degraded after just 16 weeks.  

The life of any material should be proportionate to the life of the product.  The researchers point out that it doesn’t make sense to create a product that will last 500 years if it’ll only be used for a year or two. 

The research team is currently working on production details with its manufacturing partners.  The creation of biodegradable flip-flops that meet commercial footwear standards could eliminate tons of plastic waste from the environment.   

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New science behind algae-based flip-flops

Flip Flops Market Size Worth $23.8 Billion by 2025

Photo, posted December 12, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Siberian Heat | Earth Wise

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Siberia has been experiencing unprecedented high temperatures in recent months.  May was the hottest May on record and temperatures in Siberia have stayed well above average for the past year.

On June 20, temperatures in the small Siberian town of Verkhoyansk hit 100.4 degrees Fahrenheit, which is a record-high temperature in one of the fastest-warming places in the world.  Average high temperatures in June reach 68 degrees.  Verkhoyansk sits on the Yana River in the Arctic Circle and, during the winter, is one of the world’s coldest towns.  In 1892, its temperature dropped to -90 degrees Fahrenheit.  And now there is hundred-degree heat above the Arctic Circle.

Siberia tends to experience large temperature swings month-to-month and year-to year.  But it is very unusual for temperatures to stay well over average over an extended period of time as they have for the past year.  According to climate scientists, the kind of temperature swings seen recently would only happen once in 100,000 years if it were not for climate change.

Siberia has seen raging wildfires and structural damage from thawing permafrost as its temperatures have stayed warmer than normal.  The prolonged Siberian heatwave is an alarming situation.

The Arctic is warming twice as fast as the rest of the Earth because of a process known as Arctic amplification.  The acceleration of the Arctic ice melt leads to a seasonal snow cover that isn’t as white.  It therefore absorbs more sunlight, which then leads to more warming.

The amplified warming of the Arctic with its increased melting of ice leads to higher sea levels, and not just in the Arctic Ocean.  With less Arctic ice to reflect sunlight, the world’s oceans continue to warm. 

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Temperatures in an Arctic Siberian town hit 100 degrees, a new high

Photo, posted December 7, 2014, courtesy of Olga Dudenko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mangrove Trees And Climate Change | Earth Wise

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Mangrove trees are small trees that grow in coastal saline or brackish water at tropical and subtropical latitudes.  Many mangrove trees can be identified by their dense tangle of prop roots.  These roots make the trees appear as if they are standing on stilts above the water.  The tangle of roots allows mangrove trees to handle the daily rise and fall of tides and to slow the movement of tidal waters.  

Mangrove forests provide many ecosystem services, including stabilizing the coastline by reducing erosion from storm surges, waves, and tides.  The intricate root system of mangrove trees are attractive to fish and other species seeking food and shelter from predators.  Mangrove forests also store large amounts of carbon.     

But according to a new study recently published in the journal Science, mangrove trees won’t survive sea level rise by 2050 if greenhouse gas emissions aren’t reduced.  

Using sediment data from 78 locations over the last 10,000 years, an international team of scientists led by Macquarie University in Australia estimated the chances of mangrove trees survival based on the projected rates of future sea-level rise.

When sea level rise rates exceeded 6 millimeters per year, which is similar to estimates under high-emissions scenarios for 2050, researchers found that mangrove trees were unlikely to keep pace with the rising water levels.  But when the annual increase was 5 millimeters or less – which is the projected low-emissions scenario this century – mangrove trees are much more likely to survive. 

These findings underscore the importance of reducing greenhouse gas emissions to mitigate rapid sea level rise.  The future of mangrove trees may depend on it.  

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Mangrove trees won’t survive sea-level rise by 2050 if emissions aren’t cut

Photo, posted December 17, 2012, courtesy of Edward Stojakovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Charleston Dry | Earth Wise

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Charleston, South Carolina is visited by millions of tourists each year.  The town is a glimpse into the past, showcasing antebellum mansions, row houses, historic African American churches and scenic harbor views from a Civil War-era promenade.

Charleston is also visited more and more by water from rising seas and increasingly powerful storms.  The city is essentially drowning in slow motion and may soon face an existential threat to its survival.

Charleston has a harbor and three rivers and water from all these sources leaks in at every bend and curve, fills streets, disrupts businesses, and rushes into homes during storms.  Million-dollar antebellum mansions, built on spongy marsh and old tidal creeks, flood repeatedly.

City officials have endorsed a plan by the U.S. Army Corps of Engineers to wall off the historic downtown with an 8-mile-long seawall that would cost nearly $2 billion.  The proposed barricade is just one of many proposed projects to build seawalls, surge gates, levees, and other barriers to defend U.S. coastal cities in an era of rising seas and climate-fueled floods and storms.  A proposed flood wall in Miami would cost federal taxpayers $8 billion.

Researchers generally agree that sea levels are likely to rise by at least 3 feet by the end of the century.  Some experts believe the rise will be much greater.  So, a key question is whether these barriers will actually keep out the water.  Critics of many of the proposed solutions contend that they are doomed to fail.

Flooding has caused nearly $1 trillion worth of damage along the East and Gulf coasts over the past 40 years.  And things are almost certain to get worse in Charleston and other coastal cities.

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Fortress Charleston: Will Walling Off the City Hold Back the Waters?

Photo, posted October 7, 2015, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recovering Marine Life By 2050 | Earth Wise

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Marine life has faced challenges for a long time.   There have been centuries of overfishing in many places and pollution of various types has been especially harmful in recent decades.   But despite all of this, a new scientific review published in the journal Nature contends that marine life in the world’s oceans could be fully restored in as little as 30 years provided that aggressive conservation policies are adopted.

The research spotlights the strong resiliency of ocean animals and cites the successful recovery of a number of marine species, including humpback whales.

The study indicates that nations around the world must agree to designate 20 to 30 percent of the oceans as marine protected areas, institute sustainable fishing guidelines, and regulate pollution.  These measures would not come cheaply.  The estimated cost would be around $20 billion a year. 

However, the report also estimates that the economic return on this investment would be tenfold and would create millions of new jobs.  Rebuilding fish stocks and maintaining sustainable fishing policies could increase global profits of the seafood industry by over $50 billion a year.  Conserving coastal wetlands could save the insurance industry more than $50 billion a year as well by reducing storm damage.

A major sticking point, however, is climate change.  Climate change is increasing ocean temperatures and driving acidification.  Unless these changes are brought under control, the restoration of marine life is not going to be successful.  We have reached the point where it is within our power to choose between a future with a resilient and vibrant ocean or an irreversibly disrupted ocean.  Whether we embrace that challenge remains to be seen.

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Marine Life Could Recover By 2050 With the Right Policies, Study Finds

Photo, posted April 20, 2012, courtesy of Matthias Hiltner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sea Turtles Prospering During The Shutdown | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

Seven different species of sea turtles are found in the world’s oceans and play important roles in marine ecosystems.  Over time, human activities have tipped the scales against the survival of these animals.  They have been hunted for their eggs, meat, skin, and shells and face habitat destruction and accidental capture in fishing gear.  Their nesting grounds in beaches are constantly disturbed and endangered by human activity.

With the beaches in Florida closed in the effort to stop the spread of coronavirus, there is less plastic waste, fewer people and vehicles, and fewer artificial lights on the beach that disorient emerging turtle hatchlings.  Because of all of these factors, sea turtles have been building their nests without disruptions.

In April, it was nesting season for leatherback turtles, the largest of all sea turtles. In May, loggerhead turtles arrive in Florida.  Later in the summer, green turtles will arrive.

It takes about 60 days for sea turtle eggs to incubate and to hatch.  During that period, lots of things can happen to a nest on an active beach – it can get trampled, people can dig it up, and artificial light can confuse the hatchlings as they try to find their way to the water.  With the current shutdown, it should be a productive nesting season for sea turtles.

On the other hand, when beaches reopen, there may well be a major influx of people flocking to the beach because they have been stuck indoors for an extended period of time.

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Sea turtles are thriving as coronavirus lockdown empties Florida beaches

Photo, posted August 9, 2016, courtesy of Florida Fish and Wildlife via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Rising Threat Of Rising Seas | Earth Wise

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Global sea level rose by about 6 inches during the 20th century.  It is currently rising more than twice as fast and accelerating.  The rate of rise was 2.5 times faster from 2006 to 2016 than it was for nearly all of the 20th century.

Sea level rise occurs when glaciers and ice sheets lose mass.  Much of that meltwater comes from Greenland and Antarctica.  But levels also rise because, as water warms, it expands.  Added to that are the effects of human activities such as groundwater depletion and a geological phenomenon called isostatic adjustment that is going on in parts of the East Coast where the land is actually sinking.

In Atlantic Canada, sea level rise is outpacing the global average and has already led to boardwalks swamped by swelling tides, drowned forests, submerged wharfs, and threatened historic shoreline buildings.

Recent research suggests that globally, land now occupied by 300 million people could be affected by floods at least once a year by 2050 unless carbon emissions are significantly reduced, and coastal defenses strengthened.  (This new figure is more than three times higher than earlier estimates).

Researchers at Dalhousie University in Nova Scotia are studying nature-based strategies for mitigating the effects of the rising seas.  These include conserving or restoring coastal ecosystems like dunes, wetlands, and reefs which could provide protection at a lower cost than building seawalls and other man-made obstacles.  Wetlands, for example, can reduce the force of waves and act as obstacles to storm surges, while also trapping sediment and stemming erosion.  Wetlands also serve as important carbon stores, but it is estimated that roughly half of the world’s coastal wetlands have been lost over the past 100 years to human activity and extreme weather events.

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The Looming Threat of Rising Sea Levels – And What We Can Do About it

Photo, posted February 14, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Hot November

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

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

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

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

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

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

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November 2019 was 2nd hottest on record for the planet

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

Earth Wise is a production of WAMC Northeast Public Radio.

Wildfires And Carbon

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This summer has been an unprecedented year for fires in the Arctic.  Major fires have burned throughout the Arctic in Russia, Canada, and Greenland.  In total these fires released 50 million tons of carbon dioxide in June alone, which is as much as Sweden emits in an entire year.

In an average year, wildfires around the world burn an area equivalent to the size of India and emit more carbon dioxide to the atmosphere than global road, rail, shipping and air transport combined.

Ordinarily, this is part of a natural cycle.  As vegetation in burned areas regrows, it draws CO2 back out of the atmosphere through photosynthesis.  This is part of the fire-recovery cycle, which can take less than a year in grasslands, but decades in forests.  But in Arctic or tropical peatlands, full recovery may not occur for centuries.

A recent study looked at and quantified the important role that charcoal plays in helping to compensate for carbon emissions from fires.  In wildfires, some of the vegetation is not consumed by burning, but instead is transformed to charcoal – referred to as pyrogenic carbon.   This carbon-rich material can be stored in soils and oceans over very long time periods.

Researchers have combined field studies, satellite data, and modelling to quantify the amount of carbon that is placed in storage in the form of charcoal.  Their results are that the production of pyrogenic carbon amounts to about 12% of the CO2 emissions from fires and can be considered a significant buffer for landscape fire emissions.

Charcoal does not represent a solution to the problem of increasingly intense wildfires, but it is important to take it into account in understanding what is happening.

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How wildfires trap carbon for centuries to millennia

Photo, posted August 17, 2018, courtesy of the Bureau of Land Management Oregon and Washington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

One Million Extinctions

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A group of 145 expert authors from 50 countries has produced a report based upon a review of 15,000 scientific and government sources that is the first comprehensive look at the state of the planet’s biodiversity in 15 years.  The conclusions are alarming.

Thanks to human pressures, one million species may be pushed to extinction in the next few years, something with serious consequences for human beings as well as the rest of life on earth.

Based upon scientific studies as well as indigenous and local knowledge, the evidence is overwhelming that human activities are the primary cause of nature’s decline.  The report ranked the major drivers of species decline as land conversion, including deforestation; overfishing; bush meat hunting and poaching; climate change; pollution; and invasive alien species.

The tremendous variety of living species on our plant which number at least 8.7 million and perhaps many more – biodiversity – constitutes a life-supporting safety net that provides our food, clean water, air, energy, and more.

In parts of the ocean, little life remains but green slime.  Some remote tropical forests are nearly silent because insects have vanished.  Many grasslands are becoming deserts.  Human activity has severely altered more than 75% of Earth’s land areas and has impacted 66% of the oceans.  The world’s oceans increasingly are characterized by plastics, dead zones, overfishing, and acidification.

The main message of the 1,500-page report is that transformative change is urgently needed.  In order to safeguard a healthy planet, society needs to shift from a sole focus on chasing economic growth.  This won’t be easy, but we must come to the understanding that nature is the foundation for development before it is too late.

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Web Links

One million species at risk of extinction, UN report warns

Photo, posted January 1, 2014, courtesy of Eric Kilby 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...)