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Reducing emissions from ocean shipping

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Ocean shipping is a significant contributor to global carbon emissions, accounting for about 3% of the total.  It is a key part of international trade, moving goods like electronics, automobiles, and oil.  It relies on fossil fuels, and, without significant changes, shipping’s emissions could more than double by 2050.  Ocean shipping is one of the world’s most difficult to decarbonize industrial sectors.

Scientists at the University of Southern California and Caltech, collaborating with a startup company called Calcarea, have developed a shipboard system that could remove up to half of the carbon dioxide emitted by shipping vessels. The system is fairly simple and scalable.

The process mimics a natural chemical reaction that takes place in the ocean.  As a cargo ship moves through seawater, the CO2 from the ship’s exhaust is absorbed into water that is pumped onboard.  This makes the water more acidic.  The treated water is then passed through a bed of limestone, where it reacts with the rock to form bicarbonate, which is a stable compound that already exists naturally in seawater.  The treated seawater, now stripped of the carbon dioxide, is dumped back into the ocean.

Sophisticated ocean modeling examined what would happen when the bicarbonate-rich water is released back into the sea over a hypothetical 10-year period.  The model showed a negligible impact on ocean pH and chemistry.

The researchers estimate that widespread adoption of the technique could reduce shipping-related carbon dioxide emissions by 50%.  The startup company Calcarea is working to bring the technology to market and is in early discussions with commercial shippers.

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USC technology may reduce shipping emissions by half

Photo, posted November 14, 2017, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Marine heatwaves are spreading

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Sea surface temperatures broke records in 2024 and a quarter of the world’s oceans are experiencing temperatures that qualify as a marine heatwave.  A marine heatwave is a prolonged period during which ocean temperatures are significantly warmer than average for that specific location and time of year. 

Unusual heatwaves have occurred in all the major ocean basins around the planet in recent years and some have become so intense that they are being called super marine heatwaves.

The seas off the coasts of the UK and Ireland experienced an unusually intense and long-lasting marine heatwave starting in April.  Australia was recently struck by heatwaves on two coasts.

Hotter oceans are causing drastic changes to marine life, sea levels, and weather patterns.  Some of the most apparent casualties of ocean warming have been coral reefs.  About 84% of reefs worldwide experienced bleaching-level heat stress at some point between January 2023 and March 2025.

Excess heat in the oceans can affect weather patterns, making hurricanes more likely to rapidly intensify and become more destructive.

A recent study published in Proceedings of the National Academy of Sciences concluded that climate change has been responsible for the overwhelming majority of marine heatwaves in recent decades.

People are learning to forecast these events.  Eventually, parts of the ocean might enter a constant state of marine heatwave, at least by how it is defined today.  Studying what is going on in the oceans today may provide insights into the future of the world’s oceans and provide guidance on how to try to achieve different outcomes.

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See How Marine Heat Waves Are Spreading Across the Globe

Photo, posted December 5, 2015, courtesy of Susanne Nilsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More trouble from sea urchins

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Sea Urchins are real troublemakers.  On the West Coast, the sea urchin population exploded when the sunflower sea stars that eat them were decimated by a wasting disease.  Urchins devour kelp and they ate up 96% of the region’s kelp forests.  Kelp forests serve as shelter and food for a vast array of marine life and kelp sequesters as much as 20 times more carbon than terrestrial forests.

A new study by researchers at North Carolina State University looked at the health of the coral reef in Honaunau Bay on Hawaii’s Big Island and found that ballooning sea urchin populations are endangering the survival of the reef.

Fishing in these areas has greatly reduced the numbers of fish that feed on sea urchins and urchin populations have grown significantly.   There are areas of the reef where there are 51 sea urchins in every square meter.

The reef is already not growing at a healthy rate as a result of water pollution and overheating created by climate change.  These result in a poor environment for coral to reproduce and grow, which leaves the reef unable to keep up with the pace of erosion caused by urchins.

Reef growth is measured in terms of net carbonate production – namely the amount of calcium carbonate produced over time.  In the 1980s, healthy reefs in Hawaii produced about 15 kilograms of carbonate a year per square meter.  The Honaunau Reef today shows an average net carbonate production of only 0.5 kilograms per square meter.  The reef is growing very slowly and can’t keep up with urchin erosion.

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Huge sea-urchin populations are overwhelming Hawaii’s coral reefs

Photo, posted October 29, 2017, courtesy of Rickard Zerpe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Natural solutions for disappearing islands

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Atoll islands are made from sediment produced by corals, clams, snails, and varieties of algae that secrete carbonate.  Under the right conditions, over time, fragments of coral skeletons, shells, and other sediments made by marine life are piled up by waves.  Eventually, islands are formed – some large and some small.  Atoll islands are home to a diversity of human cultures and are important refuges for a quarter of the world’s seabirds as well as numerous nesting sea turtles and tropical plants.

Rising sea levels – the rate of which has more than doubled over the past 30 years – are a mounting challenge for atoll islands.  And by the end of this century, sea level is projected to rise between 11 and 40 inches, depending on the world’s actions with regard to greenhouse gas emissions.

The ability of atoll islands to persist depends on the health of their ecosystems and the extent to which their natural processes have been disrupted by human activity.  To protect the most vulnerable islands, some researchers now propose using nature-based solutions – like restoring and protecting coral reefs and native forests.

Reclaiming seabird habitat can help reefs persist and restore the resilience of atoll islands.  Seabird guano washes off islands and into reefs, providing nutrients that boost coral growth and fish populations. 

Nature-based solutions cannot help the most urbanized atoll islands.  These islands have already irreversibly lost their natural adaptive capacity.  For those places, engineered approaches such as concrete seawalls are needed.

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How Natural Solutions Can Help Islands Survive Sea Level Rise

Photo, posted July 3, 2014, courtesy of Roderick Eime / MG Media via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The oceans are warming faster

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A new study has shown that the rate of ocean warming has more than quadrupled over the past 40 years.  The study, by researchers at the University of Reading in the UK, helps to explain why there have been unprecedented ocean temperatures in 2023 and 2024.

Global ocean temperatures hit record highs for 450 days straight in 2023 and early 2024.  Some of this unusual warmth came from the El Niño that was taking place at the time, but the rest of the increased temperature came from the sea surface warming up more quickly over the past 10 years than in previous decades.  In the late 1980s, ocean temperatures were rising at a rate of 0.06 degrees Celsius per decade.  According to the recent research, they are now increasing at 0.27 degrees per decade.

The acceleration of ocean warming is driven by growth in the Earth’s energy imbalance, meaning that more energy from the sun is being absorbed by the Earth than is escaping back into space.  This energy imbalance has roughly doubled since 2010 as a result of two factors:  increasing greenhouse gas concentrations in the atmosphere and reductions in the Earth’s albedo.

Earth’s albedo, the measure of how much sunlight is reflected back into space, has been declining since the 1970s, primarily due to the decrease in snow and ice cover, especially in the Arctic. 

The overall rate of ocean warming observed over recent decade is likely to only increase.  This underscores the urgency of reducing fossil fuel burning to avoid even more rapid temperature increases in the future.

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Ocean-surface warming four times faster now than late-1980s

Photo, posted January 18, 2007, courtesy of Alexey Krasavin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing microplastics from water

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Microplastics come from the breakdown of larger plastics in the environment as well as from direct use in various products such as certain cosmetics.  They are found everywhere, from oceans and mountain peaks to the air and water, and alarmingly, in our bodies.  They are ingested by all sorts of organisms, from tiny plankton to fish and marine mammals.  Microplastics just don’t go away.  They don’t biodegrade so they simply accumulate in the environment.

Researchers at North Carolina State University have recently demonstrated proof of concept for a system that actively removes microplastics from water.  Such a system has the potential for helping to cleanse oceans and other bodies of water from the tiny plastic particles.

The system makes use of soft dendritic colloids, which are tiny particles that have the ability to stick to just about any surface.  These sticky particles can attract microplastics and grab them, even in wet and salty conditions.  The colloids are made from chitosan, a harmless and biodegradable polymer made from processed shellfish waste.

The researchers produced small pellets of the colloids that also contain small amounts of magnesium, which makes them bubble up and rise to the surface of water.  The pellets are coated with a gelatin layer, which blocks the magnesium.  As the gelatin gradually dissolves away, the pellets collect microplastics.  Eventually, the result is a microplastic-laden scum that rises to the surface where it can be skimmed away.

The scum itself can be bioprocessed into more chitosan that can create more of these microcleaner pellets to then capture more microplastics.  The researchers are investigating how the process can be scaled up to become a valuable tool in dealing with the microplastics problem.

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New Water Microcleaners Self-Disperse, Capture Microplastics and Float Up for Removal

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Antarctic greening

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The Antarctic Peninsula, like other polar regions, is warming faster than the rest of the world.  Ocean heatwaves and ice loss are becoming more common and more severe.

New research by the universities of Exeter and Hertfordshire in the UK along with the British Antarctic Survey used satellite data to assess how much the Antarctic Peninsula has been greening in response to climate change.  The Antarctic Peninsula is an 800-mile extension of Antarctica toward the southern tip of South America.

The study found that the area of vegetation cover across the Peninsula increased from less than one square kilometer in 1986 to almost 12 square kilometers in 2021.  This greening trend accelerated by more than 30% in the period 2016-2021 relative to the entire 1986-2021 period.

An earlier study also showed that the rates of plant growth on the Antarctic Peninsula has increased dramatically in recent decades.  The landscape is almost entirely dominated by snow, ice, and rock, with only a tiny fraction supporting plant life.  The plants found on the Peninsula – mostly mosses – grow in some of the harshest conditions on earth.  But that tiny fraction has greatly increased, showing that this isolated wilderness is being altered by climate change. 

The sensitivity of the Antarctic Peninsula’s vegetation to the changing climate is evident and as warming continues, there could be fundamental changes to the biology and landscape of this unique and vulnerable region.

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Antarctic ‘greening’ at dramatic rate

Photo, posted June 2, 2018, courtesy of Murray Foubister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Deep sea mining

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Deep sea mining is the extraction of minerals from the ocean floor at depths greater than 660 feet and as much as 21,000 feet below the surface.  Active or extinct hydrothermal vents on the ocean floor create sulfide deposits which collect metals such as silver, gold, copper, manganese, cobalt, and zinc.  This forms polymetallic nodules – potato-sized rocklike deposits containing these valuable minerals.  There are literally trillions of these things scattered over wide areas of ocean floor.  The largest of these deposits are in the Pacific Ocean between Hawaii and Mexico in the Clarion Clipperton Fracture Zone.

Mining companies argue that land-based sources for valuable metals are running out and are critically needed for green technologies like batteries for electric vehicles and manufacturing solar panels and wind turbines.  They also claim that mining in the deep sea will be less environmentally damaging than land-based mining.

The deep sea is viewed by many as kind of a watery desert but there are actually diverse and rich ecosystems down there.  Most of the animals living in the depths are tiny, but that doesn’t make them any less important.  Many can live for a very long time.  Some invertebrates live for thousands of years.

There are currently no commercial deep sea mining operations underway.  Many countries have outlawed them.

The deep seas are the last mostly unexplored part of the Earth.  Deep sea mining will unquestionably be highly destructive to these environments.  We don’t really know what the impact of widespread deep sea mining might be, but the world continues to edge ever closer to allowing it to happen.

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Can We Mine the World’s Deep Ocean Without Destroying It?

Photo, posted March 30, 2018, courtesy of the NOAA Office of Ocean Exploration and Research via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind farms and sea farms

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There has been increasing use of agriculture coexisting with solar farms.  This dual use of land is a win-win situation.  Recently, Danish researchers have been investigating the potential for farming marine products at offshore wind farms.

Scandinavia’s largest wind farm, Kriegers Flak, is the site of a four-year-old project in which long lines are stretched between the wind farm’s pylons and are used to grow mussels and seaweed.  With the first harvest that has taken place after 18 months, it is showing signs of early success.

Seaweed and mussels are low trophic aquaculture crops.  That means that that they don’t need to be fed or fertilized.  They take up nutrients from the sea and produce healthy foods.

The 328-foot lines spread between the turbines can be used to grow substantial quantities of the underwater seafood.  According to modeling by Aarhus University – the institution conducting the study – using just a tenth of Denmark’s wind park area could produce tons of seafood annually while using only the naturally-available resources.  This form of aquaculture captures emissions instead of producing them.

Researchers say that it is time to develop guidelines to encourage companies to plan for multiple uses of the ocean because countries are ramping up production of clean energy from offshore wind farms.  Denmark was the first country in the world to install a commercial offshore wind park in 1991.  Over 30 years later, nearly half of the country’s electricity comes from wind turbines.

The benefits of such sea farms combined with offshore wind farms go beyond food production and clean energy production.  They also help improve water quality and capture carbon.  It is another win-win situation.

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Beneath offshore wind turbines, researchers grow seafood and seaweed

Photo, posted August 5, 2007, courtesy of Andreas Klinke Johannsen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Barley plastic

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The durability, malleability, and low cost of plastics have made them ubiquitous.  Plastics are everywhere:  in packaging, clothing, and an endless variety of products.  As a result, they are everywhere in the environment and they tend to stay there, contaminating land and sea.  They are tough to recycle, and their production emits more carbon dioxide than all air traffic combined.  The search for viable substitutes for plastic is global and intensive.

Most common bioplastics are not an ideal solution.  They don’t break down that easily when tossed into the natural environment.  The process can take years. 

Researchers at the University of Copenhagen have invented a new material made from modified starch that can completely decompose in nature and can do so in only two months.  The material is made using natural plant material from crops and could be used for food packaging as well as many other things.

The new material is a biocomposite composed of several substances that decompose naturally.  The main ingredients are amylose and cellulose, common in many plants.  Amylose is extracted from crops like corn, potatoes, wheat, and barley.

The Danish researchers have developed a barley variety that produces pure amylose in its kernels.  Pure amylose is ideal because it is less likely to turn into a paste when it interacts with water. 

Combining the amylose with cellulose forms long, strong molecular chains, resulting in a durable, flexible material that can replace plastic in many applications.  The research team has founded a spinoff company and have applied for a patent for the new material.  It is unclear when the biofriendly barley-based plastic might be commercialized, but its potential is quite good.

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Researchers invent one hundred percent biodegradable “barley plastic”

Photo, posted May 20, 2010, courtesy of Frederick Lang Jr. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Averting a mass extinction

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There has been widespread concern that biodiversity is under siege and that we are in the beginnings of a sixth mass extinction in the long history of the Earth, this time caused by the actions of humanity.  There has been considerable debate about what can be done about it and solutions generally involve protecting large areas of the planet from human disruptions.  Some countries have set a target of protecting 30% of land and sea.

A new study by a broad coalition of conservation organizations and published in Frontiers in Science, concludes that humans can preserve much of the great diversity of life on Earth by setting aside just 1.2% of the planet for protection.

The experts mapped the wilderness available to rare and threatened plants and animals.  They then identified specific hotspots for rare wildlife that have yet to be protected.  They found a total of 16,825 such sites which nevertheless all together add up an area smaller than the state of Wisconsin.

Some scientists have been warning that by focusing too much on the size of protected lands, we are not necessarily safeguarding areas that are especially rich in wildlife.  The new study pushes for prioritizing hotspots for rare species, which the authors claim would be sufficient to stave off a sixth mass extinction.  The truth is that most species on Earth are rare, meaning that they are few in number or cover a small range, or both.

The study estimated that the cost of protecting the identified hotspot sites would be $263 billion, which is certainly a large amount of money.  But the authors point out that this sum to save global biodiversity is less than the yearly revenue of Shell Oil.

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To Avert a Mass Extinction, Protect 1 Percent of Earth

Photo, posted April 20, 2018, courtesy of Per Harald Olsen / AfricanBioServices via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Eliminating plastic shipping pillows

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Anyone who gets packages from Amazon is familiar with the plastic air pillows used to keep products safe in transit.  Amazon uses almost 15 billion of them a year in North America.

Environmentalists have been urging Amazon and other vendors to cut down on the use of plastic packaging. The air-filled plastic pillows are made from plastic film, which is the most common form of plastic litter found in the sea and in seabeds along the shore.  Plastic film can be deadly to wildlife such as sea turtles and sea birds.  Plastic film generally can’t be composted or recycled either.

Recently, Amazon announced that it will replace its plastic pillows with recycled paper filler in all its North American markets – the United States, Canada, and Mexico – which together account for more than 70% of the retailer’s global sales.  It is already making the switch in a big way and is working towards fully removing the plastic materials by the end of the year.

Replacing plastic packaging with paper is a definite improvement.  Paper is recyclable and biodegradable.  It isn’t perfect:  if it ends up in landfills, it can contribute to methane pollution as it biodegrades.  But, on the other hand, paper packaging is more likely to be recycled.

Stemming the tide of plastic waste is an ongoing effort by environmental and consumer groups.  There is pending legislation in New York that aims to reduce the use of plastic packaging by 50% over 12 years by requiring manufacturers to either replace it or pay fees.  The bill cleared the State Senate but has not come up to a vote in the Assembly.  Similar legislation has already been passed in California, Oregon, Maine, and Colorado.

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Amazon Says It Will Stop Using Puffy Plastic Shipping Pillows

Photo, posted November 20, 2018, courtesy of Todd Van Hoosear via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An ice-free Arctic

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According to a new study by Colorado University, Boulder, the Arctic could see summer days with practically no sea ice as soon as sometime in the next few years.  Earlier predictions for when the first ice-free day in the Arctic could occur were sometime well into the 2030s.

By mid-century, the Arctic is likely to see an entire month without floating sea ice.  This would likely be in September, when ice coverage is at its minimum.  By the end of the century, the ice-free season could last for many months during the year.

Technically, an ice-free Arctic does not mean zero ice in the water.  The working definition is less than 386,000 square miles of ice, which represents less than 20% of what the minimum ice coverage was in the 1980s. In recent years, the coverage has been about 1.25 million square miles.

Sea ice coverage is a big deal because many Arctic animals rely on sea ice for survival, including seals and polar bears.  With warmer ocean water, invasive fish species could move into the Arctic Ocean, upsetting local ecosystems.  Sea ice loss also is a risk for coastal communities because the ice buffers the impact of ocean waves on the coastal land.  As the ice retreats, ocean waves would get bigger, eroding the coasts.

At this point, an ice-free Arctic is basically inevitable, but its annual duration will depend on society’s efforts to reduce carbon emissions.  Lengthy periods of minimal sea ice would transform the Arctic into a completely different environment with global effects that are mostly highly undesirable.  However, Arctic sea ice is resilient and could return fairly quickly if the atmosphere cools down.

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The Arctic could become ‘ice-free’ within a decade

Photo, posted July 9, 2022, courtesy of Reiner Ehlers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mercury in tuna

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Mercury is found throughout the ocean, and there is at least some of it in any fish one might eat. It is an element found naturally in the environment, but it is also a byproduct of manmade pollution. Generally speaking, bigger fish tend to have higher mercury levels than smaller ones, because they are higher up in the food chain. The more small fish those big fish eat, the more mercury builds up in their bodies.  Tuna aren’t the biggest fish in the ocean, but they are very common in many people’s diets.

Increased mercury levels are a result of human activities like burning coal and mining which release methylmercury into the air.  It then finds its way into the oceans in rainwater.  Methylmercury is a particularly toxic chemical that affects the nervous system.  Environmental protection policies in recent decades have helped to reduce mercury pollution.

However, a recent study by French researchers looked at the mercury levels in tuna over the past 50 years.  They found that the levels have basically not changed since 1971.  As a result, they are calling for more restrictive environmental policies to further lower mercury pollution levels.

The researchers explained that the lowering of mercury airborne levels to date has not necessarily been ineffective.  They theorized that the static levels in tuna may be caused by the upward mixing of “legacy” mercury from deeper ocean water into the shallower depths where tropical tuna swim and feed.  It could very well take decades to dramatically reduce ocean mercury levels. 

Meanwhile, mercury content in tuna varies considerably by tuna type and source and there are both better and worse choices out there.  Consumers should learn the facts.

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Mercury levels in tuna remain nearly unchanged since 1971, study says

Photo, posted November 7, 2015, courtesy of Mussi Katz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

What did the record warmth of 2023 mean?

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2023 was the warmest year in the 174 years of global temperature record-keeping.  According to some analyses, it may have been the warmest year in the past 125,000 years.

There were incredible heatwaves in Arizona and Argentina.  There were relentless wildfires across Canada.  The wintertime ice coverage in the seas surrounding Antarctica was at unprecedented lows

The global temperatures in 2023 did not just beat prior records; they smashed them.  Every month from June through November set all-time monthly temperature records. The US Northeast saw springlike temperatures at the end of the year.  The high temperature in Buffalo, New York on Christmas Day was 58 degrees.

Climate scientists have been predicting the warming trend that has been ongoing over the past several decades.  Indeed, computational models for 2023 called for a warm year.  Various models had a variety of projected temperatures and 2023’s heat was still broadly within the range of what was projected, although certainly at the high end.

The question is whether last year was an indicator that the planet’s warming is accelerating faster than we expect or that it just was a particularly warm year because of cyclical factors such as the El Niño that appeared last spring.

One theory that is being explored is that various types of industrial pollution have previously actually served to cool the atmosphere over time and as those sources are reduced for public health reasons, the warming effects of greenhouse gases have accelerated.

Currently, there is no consensus about why it seems to be getting warmer even faster than many climate models predict.  What there is no doubt about is that it is not a good thing.

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Earth Was Due for Another Year of Record Warmth. But This Warm?

Photo, posted June 8, 2023, courtesy of Anthony Quintano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record low Antarctic sea ice

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Antarctica’s winter came to a close in September and during that month, the continent reaches its maximum amount of sea ice that grows during the darkest and coldest months.  This year, that maximum occurred on September 10th and turned out to be the lowest on record.

The sea ice around Antarctica reached a maximum extent of 6.5 million square miles according to NASA researchers.  That was nearly 400,000 square miles below the previous record low set in 1986. 

There are several possible causes for the meager growth of Antarctic sea ice this year.  It may be a combination of several factors including El Niño, wind patterns, and warming ocean temperatures.  Recent research indicates that ocean heat is most likely playing an important role in slowing ice growth in the cold season and enhancing ice melting in the warm season.

The record-low ice extent so far this year is a continuation of a downward trend in Antarctic sea ice that has gone on since the ice reached a record high in 2014.  Prior to that year, the ice surrounding the southern continent was actually increasing slightly by about 1% every decade.

Meanwhile, Arctic sea ice reached its minimum extent in September and it was the sixth-lowest level in the satellite record.  Scientists track the seasonal and annual fluctuations of polar sea ice because they shape polar ecosystems and play a significant role in global climate.  Sea ice melting at both poles reinforces global warming because bright sea ice reflects most of the Sun’s energy back to space while open ocean water absorbs 90% of it.

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Antarctic Sea Ice Sees Record Low Growth  

Photo, posted June 30, 2023, courtesy of Pedro Szekely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Floating Sea Farms | Earth Wise

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Researchers at the University of South Australia have designed a self-sustaining solar-driven system that turns seawater into fresh water and grows crops without any involvement.  In theory, such a system could help address the growing problems of freshwater shortages and inadequate food supplies as the world’s population continues to increase.

The system can be described as a vertical floating sea farm.  It is made up of two chambers:  an upper layer similar to a greenhouse and a lower chamber for water harvesting.

Clean water is supplied by an array of solar evaporators that soak up seawater, trap the salts in the evaporator body and, heated by the sun, release clean water vapor into the air which is then condensed on belts that transfer the water into the upper plant growth chamber.

The researchers tested the system by growing broccoli, lettuce and bok choi on seawater surfaces without maintenance or additional clean water irrigation.  The system was powered entirely by solar light.

The design is only a proof-of-concept at this point.   The next step is to scale it up using an array of individual devices to increase plant production. 

The futuristic potential for such technology would be huge farm biodomes floating on the ocean.  The UN estimates that by 2050, nearly 2.5 billion people are likely to experience water shortages while the global supply of water for irrigation is expected to decline by 19%.  Nearly 98% of the world’s water is in the oceans.  Harnessing the sea and the sun to address growing global shortages could be the way to go.

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Floating sea farms: a solution to feed the world and ensure freshwater by 2050

Photo, posted February 11, 2015, courtesy of Ed Dunens via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trouble For Emperor Penguins | Earth Wise

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Emperor penguins are the tallest and heaviest of all living penguin species.  The loss of sea ice in Antarctica last year has led to unprecedented breeding failure in some emperor penguin colonies.

In a study published by the British Antarctic Survey, researchers found that no chicks survived from four of the five known emperor penguin colonies in the central and eastern Bellinhausen Sea.   Satellite images showed the loss of sea ice at breeding sites, well before chicks would have developed waterproof feathers.

Emperor penguins are dependent on stable sea ice that is firmly attached to the shore from April through the end of the year.  Arctic sea ice reached an all-time low in December 2022 with the most extreme loss seen in the central and eastern Bellinghausen Sea where there was a 100% loss of sea ice late the year.

This year, the sea ice extent in Antarctica is still far below all previous records for this time of year.  As of August, when oceans normally are freezing up, there were still areas that were ice-free.

Emperor penguin populations have not had to contend with large-scale hunting, habitat loss, overfishing, or other human-caused problems in the modern era, but climate change may be their undoing.  They have previously responded to incidents of sea ice loss by moving to more stable sites in the following year.  But this strategy will not be successful if the sea ice habitat is affected across entire regions of Antarctica.

Scientists are predicting that 90% of emperor penguin colonies will be quasi-extinct by the end of the century, assuming current global warming trends continue.

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Loss of sea ice causes catastrophic breeding failure for emperor penguins

Photo, posted October 7, 2017, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More Offshore Wind Proposed For New Jersey | Earth Wise

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There have been three offshore wind projects previously approved by utility regulators in New Jersey.  New Jersey is vying to become an East Coast leader in the fast-growing offshore wind industry and now developers have proposed four new projects off the New Jersey Shore.

Two of the projects would be located far out to sea where they would not be visible at all from the shore.  One of them, called Community Offshore Wind, would be built 37 miles offshore from Long Beach Island.  It aims to generate enough electricity to power 500,000 homes.

A second project, called Leading Light Wind, would be located 40 miles off Long Beach Island and would consist of up to 100 turbines that would generate enough electricity to power 1 million homes.

The two companies that are building the already-approved Atlantic Shores Wind Farm have submitted a bid for a new project located 10 to 20 miles offshore.  In addition, a fourth application to the New Jersey Board of Public Utilities has also been submitted, but there is yet no public information about it.

Existing offshore projects have drawn intense opposition from homeowners in part because they are close enough to the Atlantic City and Ocean City shorelines to be seen by beachgoers, albeit as tiny objects on the horizon.  The new proposed projects located far offshore would not have this problem.

The new projects can take advantage of existing federal tax credits, but the bidders say they will not seek the tax breaks from New Jersey that the earlier project received as they have also been the subject of legal challenges by opponents of offshore wind.

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4 new offshore wind power projects proposed for New Jersey Shore; 2 would be far out to sea

Photo, posted March 25, 2016, courtesy of TEIA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving Florida’s Corals | Earth Wise

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When corals are exposed to extended periods of excess heat, they are subject to bleaching, which occurs when they expel the algae that live within their structure.  Bleaching can lead to coral death.

This summer, temperatures in the Florida Keys crossed the bleaching threshold in mid-June and remained above it for extended periods of time.  This cumulative heat exposure leads to widespread bleaching and significant die-offs.  The last major mass bleaching event in the Florida Keys occurred in 2014 and 2015.

The Coral Restoration Foundation has been receiving reports ranging from partial bleaching to mass coral mortality throughout the keys.  Several coral restoration sites in the lower Keys have been totally lost already.

The National Oceanic and Atmospheric Administration and its state agency, university, and non-profit partners have initiated actions to try to save Florida’s corals.

They have halted all restoration-related planting and are evacuating some of their nursery-grown stock to climate-controlled labs.  They are considering interventions such as shading coral nurseries or even high-value reef sites.  They are also considering feeding nursery and wild corals until the waters cool off enough for algae to return.

Modeling indicates that there is a 70-100% chance that the extreme heat in the North Atlantic will persist through September-October.  NOAA and its partners will continue to do what they can to save Florida’s Coral Reef for the marine and human communities that depend on them.

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NOAA and partners race to rescue remaining Florida corals from historic ocean heat wave

Photo, posted April 19, 2012, courtesy of U.S. Fish and Wildlife Service Southeast Region via Flickr.

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