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Restored wetlands and climate

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Forests are well-known to be major storehouses of carbon in the environment.  Less known but also extremely important are peatlands and wetlands and, like forests, both have suffered declines as a result of human activity.  And, like forests, both are seeing efforts at restoration.

Restoring peatlands has the drawback that it initially causes a spike in methane emissions, and it therefore takes a long time for them to have a net positive effect on the climate after they are restored. 

In a new study by RMIT University in Australia, it was found that reviving floodplain wetlands reduces carbon emissions by 39% and restores critical ecosystem functions in one year without any increase in methane emissions.  The 6-year study reintroduced water flow to a degraded freshwater wetland.  Over the course of the study, carbon stocks in the wetland increased by 53%.  Freshwater wetlands cover less than 10% of the Earth’s surface but contribute up to 25% of global methane emissions.  Despite this, they still play a crucial role in global ecosystem function.

Floodplain or riparian wetlands comprise over half of global wetlands.   They store less carbon than peatlands but restoring them gains substantial ecosystem benefits quickly.  The carbon is stored in plant roots and soil.  Wetlands are nature’s purification system removing both nitrogen from waterways and carbon from the atmosphere. 

Restoring and managing freshwater wetlands for the purpose of carbon sequestration also boosts flood and drought resilience.  Riparian wetlands are connected to other ecosystems like rivers and streams and provide benefits to them.

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Restored wetlands reap benefits for climate, drought-resilience after just one year: study

Photo, posted January 7, 2014, courtesy of Tom Barnes / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

What happened to the sea stars?

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Billions of sea stars off the Pacific coast of North America from Mexico to Alaska have died from a wasting disease since 2013.  This die-off is considered to be the largest ever marine epidemic.  Over 90% of the population of sunflower sea stars has succumbed to the disease.

The result has been an explosion in the population of the sea urchins that the sea stars feed on.  In turn, the sea urchins have devoured kelp forests that provide habitat for thousands of marine creatures.  These kelp forests support a multi-million-dollar economy through fisheries and tourism as well as sequestering carbon dioxide and protecting vulnerable coastlines. 

The disease begins with lesions and eventually kills sea stars by seemingly melting their tissues over a period of about two weeks.  Sea stars with the disease become contorted and lose their arms.

For years, the definitive cause of the wasting disease has been elusive.  But researchers from the University of British Columbia, the Hakai Institute, and the University of Washington have now identified a bacterium that is the disease-causing agent.

A strain of the Vibrio pectenicida bacteria – named FHCF-3 – is responsible.  The Vibrio genus of bacteria includes pathogens that infect corals, shellfish, and even humans.  Vibrio cholerae is the cause of cholera.

Research is now underway to understand the link between the disease and warming ocean temperatures due to climate change.  The hope is that the discovery of the cause of the wasting disease will help guide management and recovery efforts for sea stars and impacted ecosystems.

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‘Disease detectives’ discover cause of sea star wasting disease that wiped out billions of sea stars

Photo, posted April 16, 2011, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Abandoned farmland and the environment

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Abandoned farmland has been increasing dramatically in recent decades.  Estimates are that a billion acres – an area half the size of Australia – have been relinquished from cultivation globally.  While more and more of the tropics have been cultivated in recent times, the global amount of land used for agriculture has been in decline since 2001.  In the past 30 years, arable land in the United States has declined by almost a sixth.  The situation in Europe is similar.  Huge amounts of the former Soviet Union now lie abandoned. 

Farmland is abandoned for various reasons.  It may suffer from damaged soil so that crop yields are too low to be worth the effort.  Farm owners may become too old or be physically unable to continue farming.  Many younger people head for jobs in the cities and more attractive opportunities.  Wars, natural and man-made disasters, and political turmoil have all contributed.

Another form of largely ignored lands are so-called degraded forests.  These are forests that were logged in the past but are no longer productive and aren’t protected either.  These places also represent unused land with great potential value.

Ecologists point to the potential of these lands as neglected resources for rewilding efforts, improving biodiversity, and for increasing natural ways to capture carbon.  Left to its own devices, nature will usually reclaim abandoned places.  This generally provides benefits for biodiversity and climate.  But mapping, studying, managing, and protecting the increasingly vast tracts of abandoned land could increase their potential to contribute to climate change mitigation and the restoration of species and their habitats.

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Abandoned Lands: A Hidden Resource for Restoring Biodiversity

Photo, posted January 26, 2023, courtesy of Larry Syverson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildfires and water quality

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Hotter and drier conditions driven by climate change are leading to an increasing number of wildfires in North America and around the world. The damage wildfires cause – to forests, homes, and communities – is well-known. But long after the flames are gone, the effects can linger, especially in rivers and streams, where water quality may suffer for years.

A new study by scientists at the CIRES institute at the University of Colorado Boulder analyzed more than 100,000 water samples from more than 500 sites across the Western U.S. and found that wildfires can degrade water quality for up to eight years after a fire. The research, which was recently published in the journal Nature Communications Earth & Environment, found elevated levels of organic carbon, nitrogen, phosphorus, sediment, and turbidity – the cloudiness of water – in basins affected by fire.

This large-scale analysis reveals watersheds take longer to recover from wildfires than previously thought, with widespread, long-lasting impacts often going undetected for years.

Organic carbon, phosphorus, and turbidity remain elevated for one to five years after a fire. Nitrogen and sediment levels stay notably high for up to eight years. Fire-driven impacts are worse in more forested areas.

Each watershed in the study responded differently depending on local conditions.  In some places, sediment levels surged to as much as 2,000 times normal levels, while others remained relatively unchanged.

The research team hopes its findings can help guide future planning efforts to improve wildfire resilience.

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Wildfires threaten water quality for years after they burn

Photo, posted April 6, 2017, courtesy of Bonnie Moreland 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

Record forest loss

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The world lost a record amount of forests last year.  The biggest factor for the unprecedented losses were wildfires that raged around the world.

According to the annual update by the University of Maryland and the World Resources Institute, pristine rainforests alone lost 17 million acres, which was nearly twice as much as in the previous year.  Overall, the world lost the equivalent of 18 soccer fields of forested land every minute last year.

Over time, agriculture has been the primary cause of forest losses, but last year, for the first time since record-keeping began, fires were the leading cause, accounting for nearly half of all the destruction.

With respect to the climate, wildfires emitted over 4 billion tons of greenhouse gasses, which is more than four times the amount generated by air travel in 2023.

Land clearing for agriculture, cattle farming, and other purposes was by no means in decline last year.  In fact, it rose by 14%, which was the sharpest increase in almost a decade.  This trend could permanently transform critical natural areas, unleashing large amounts of carbon, intensifying climate change, and fueling even more extreme fires.

Forests are a major contributor to the natural storing of carbon dioxide.  Intact tropical forests are especially effective at storing carbon.

Brazil has the largest area of tropical forest and it accounted for 42% of all tropical primary forest loss in 2024.  Fires fueled by the worst drought on record caused two thirds of that loss, more than a sixfold increase over the previous year.

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Global Forest Loss Hit a Record Last Year as Fires Raged

Photo, posted September 12, 2024, courtesy of the USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving birds from buildings

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Researchers estimate that hundreds of millions of birds die hitting buildings every year in the United States.  Striking buildings is believed to be one of the major factors behind the nearly 30% decline in North American bird populations since 1970.

Chicago is one of the most dangerous cities for migrating birds based on its location and its numerous tall, glassy buildings.  Migrating birds that make their homes in forests and grasslands don’t perceive glass as solid and are confused by reflections.

While many Chicago skyscrapers are dangerous for birds, the Lakeside Center at McCormick Place is infamous for the fact that it claimed the lives of nearly a thousand birds on a single day in October 2023.

There are various strategies for reducing bird strikes.  Over decades, McCormick Place management has tried erecting strips of netting, broadcasting calls of birds of prey, and putting up silhouettes of them.  They commissioned a nine-acre park of native prairie and woodlands on the roof of a parking deck.  None of these things made a major difference.

Last summer, the building installed a pattern of dots over the surface of the building’s windows.  The dots are only a couple of inches apart, so even tiny hummingbirds don’t try to dart through.  The window treatment cost $1.2 million paid for by the state of Illinois.  People in the building scarcely notice the dots.  Their views of the city and lake are unimpaired.

The results are nothing short of remarkable.  During last fall’s migration, bird deaths were down by about 95% compared with the two previous autumns.  This spring’s migration has been with implications for glassy structures far beyond Chicago.

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An Illinois Building Was a Bird Killer. A Simple Change Made a World of Difference.

Photo, posted May 19, 2023, courtesy of Warren LeMay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Restoring oil well sites with moss

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Researchers at the University of Waterloo in Canada have developed a method for restoring peatlands at tens of thousands of oil and gas exploration sites in Western Canada. 

A well pad is a prepared area used for drilling oil or gas wells, encompassing the site where drilling equipment, wellheads, and related facilities are located.  Preparing well pads involves burying native peatland vegetation under clay or sand, thereby eliminating the ability of the peatland to sequester carbon as well reducing available habitat for wildlife.

Restoring well sites has typically involved planting trees or grasses to eventually establish forests or grasslands.  The Waterloo method returns a well pad to its condition before drilling occurred and is part of ongoing efforts to restore peatlands, which are known to be even more effective for sequestering carbon than tropical forests.

The Waterloo technique involves lowering the surface of a decommissioned well site and transplanting native mosses onto it to effectively recreate a peatland.    They tested the technique to scale at an entire well pad and found that it results in sufficient water for the growth of peatland moss across large portions of the study site.

The results suggest that re-establishment of peatland vegetation on lowered well pads is possible.  The researchers plan to continue monitoring the ecosystem in the study’s well pads to confirm that the transplanted mosses will be self-sustaining over the coming decades.  They will focus on increasing the amount of water that flows from surrounding natural peatlands into the converted well pads to further optimize soil moisture. 

This work could represent an important milestone in ecological restoration.

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Restoring oil wells back to nature with moss

Photo, posted November 6, 2014, courtesy of Chris Boyer / Kestrel Aerial Services via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Nature: An important climate ally

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Nature is often seen as a victim of climate change, but it’s also one of the most powerful tools we have to fight it. Natural ecosystems, such as forests, wetlands, grasslands, oceans, and soils, absorb and store massive amounts of carbon dioxide. These ecosystems not only help reduce the concentration of greenhouse gases in the atmosphere, but they also regulate temperatures and provide buffers against extreme weather.

One of the most effective strategies for mitigating climate change is simply protecting and restoring these natural areas. For example, mangrove forests – those coastal wetlands filled with tangled, salt-tolerant trees – sequester carbon at high rates and help protect coastal communities from storm surges and rising seas.  Peatlands – another type of wetland – store more carbon than all the world’s forests combined – despite only covering 3% of Earth’s land surface.  Global restoration efforts are underway, from replanting mangroves in Southeast Asia to rewetting degraded peatlands in Europe.

Creating urban green spaces like parks and community gardens, restoring forests through native tree plantings, and adopting sustainable agricultural practices like cover cropping and agroforestry are all proven to be low-cost, high-impact climate solutions. 

While nature-based solutions are gaining recognition, they remain critically underfunded, according to a recent United Nations report.  Closing this gap is essential to unlocking nature’s  full climate potential.

Investing in nature isn’t just about preserving Earth’s natural beauty.  It’s a practical strategy for building a more resilient and sustainable future.

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Mangrove forests and rising seas

Financing Nature-based Solutions for a better future

Finding peatlands

The Importance Of Urban Green Spaces

Photo, posted October 23, 2011, courtesy of the Everglades National Park / NPS 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

The UN Carbon Market

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The UN climate conference in November approved an official market for large-scale trading of carbon credits.  This will allow industrial countries to help meet their emission reduction targets set by the Paris Climate Agreement by paying other nations to protect and restore forests and carbon-rich peatlands.

The first major participant in this multi-billion-dollar enterprise is Indonesia.  That country is home to the world’s third largest expanse of tropical rainforests and more than a third of the world’s carbon-storing peatlands.  Indonesia’s government plans to raise up to $65 billion by 2028 by selling carbon credits accrued by restoring and protecting its forests and peatlands.

The problem with carbon trading is that it can be filled with loopholes ranging from inaccurate carbon accounting to outright fraud.  Carbon trading with both individual companies and other countries can result in double- and even triple-counting of the same carbon.

For example, carbon credits are assigned when forests earmarked for agricultural or other development are preserved instead of being felled.  But what if that forest destruction wasn’t going to happen even without selling carbon credits? 

There are organizations in the business of verifying carbon accounting, but independent analysis of their methodologies has revealed serious shortcomings, and in many cases, the verifications have been deemed to be worthless.

There are real problems with carbon accounting and setting correct baselines for the carbon emission reductions associated with carbon credits.  Nevertheless, the existence of a global carbon market can be an important tool in the world’s efforts to mitigate the effects of climate change.

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Will UN Carbon Market Work? Indonesia Will Provide First Test

Photo, posted June 12, 2017, courtesy of Runa S. Lindebjerg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Unexplained heat wave hotspots

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2023 and 2024 have been the hottest years since records have been kept.  But above and beyond the upward march of average temperatures around the globe, there has been the phenomenon of distinct regions across the globe experiencing repeated heatwaves that are so extreme that they cannot be accounted for in any models of global warming.

A new study by Columbia University’s Climate School has provided the first worldwide map of such regions, which have emerged on every continent except Antarctica.  Heatwaves in these regions have killed thousands of people, withered crops and forests, and triggered devastating wildfires.

These recent regional-scale record-breaking temperature extremes have raised questions about whether current climate models can provide adequate estimates of the relationship between global mean temperature changes and regional climate risks.

Some of these regional events in recent years include a nine-day heatwave in the U.S. Pacific Northwest and southwestern Canada in June 2021 that broke daily records in some places by 54 degrees Fahrenheit.  Across Germany, France, the UK, the Netherlands, and other countries, the hottest days of the year are warming twice as fast as the summer mean temperatures. 

There is yet little understanding of the phenomenon.  Some theories related to destabilization of the jet stream don’t really explain all the temperature extremes observed.  But regardless of the underlying causes, the health impacts of these heat waves are severe, as are the effects on agriculture, vegetation, and infrastructure.  Society is not built to quickly adapt to them.

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Unexplained Heat Wave ‘Hotspots’ Are Popping Up Across the Globe

Photo, posted August 16, 2022, courtesy of Alisdare Hickson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Regrowing forests naturally

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Deforestation is one of the major causes of climate change and restoring and enhancing forests is a major activity around the world as a way to mitigate its effects.  There are high-profile initiatives to plant millions of trees, but these projects are often ill-conceived and poorly managed.

One of the most dramatic failures was the planting of over a million mangrove seedlings on the Filipino island of Luzon back in 2012.  A study 8 years later found that fewer than 2 percent of the trees had survived.  The rest died or were washed away.

The causes of failure in tree planting programs include planting of trees that become vulnerable to disease, competing demands for land, changing climate, planting in areas not previously forested, and a lack of aftercare including watering seedlings.

A multinational study recently published in Nature has found that forests could regrow naturally on more than 800,000 square miles of land around the tropics without the need for planting trees by hand.  This is an area larger than Mexico.

The researchers mapped areas where forests would be likely to regrow – areas where soils are healthy and where there is already forest nearby to supply seeds.  In some places, lands are so degraded that it is necessary to plant trees by hand, but this is costly and prone to failure.  Forests that regrow naturally tend to fare better and make better habitats for wildlife.

The effect of regrown forests on the climate would be very substantial.  If these forests were allowed to grow for three decades, they would absorb enough carbon to offset 50 years of emissions by Australia, the home of the lead researcher of the study. 

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Tropical Forests Could Regrow Naturally on Area the Size of Mexico

Photo, posted February 16, 2018, courtesy of Jason Houston / USAID via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mangrove forests and rising seas

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Mangrove forests play a vital role in the health of our planet.  They protect coastal regions by acting as natural barriers against storms, erosion, and flooding. The intricate root systems of mangrove forests, which allow the trees to handle the daily rise and fall of tides, also serve as biodiversity hotspots, attracting fish and other species seeking food and shelter from predators.

But mangrove forests around the world are under increasing threat from deforestation, coastal development, and climate change.  In fact, according to a new study led by researchers from Northumbria University in England, the mangrove trees in the Maldives are actually drowning. 

The research, which was recently published in the journal Scientific Reports, found that sea levels around the Maldives rose more than 1.18 inches per year from 2017 to 2020.  An unusually intense climate phenomenon, known as the Indian Ocean Dipole, occurred toward the end of this period, causing warmer sea surface temperatures and an increase in sea level in the Western Indian Ocean. 

While mangrove forests can naturally keep pace with gradually rising seas, this rate of sea level rise was too fast.  The rising sea level meant that seawater effectively flooded mangrove forests, causing many trees to lose their resilience and die.  Some islands in the Maldives have lost more than half of their mangrove cover since 2020.

Since mangrove forests also store massive amounts of carbon, the research team fears that the loss of mangrove forests could release large amounts of carbon, further accelerating climate change.

The researchers warn that the findings in the Maldives could have implications for coastal ecosystems around the world.

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“Drowning” mangrove forests in Maldives signal global coastal threat

Photo, posted February 11, 2015, courtesy of Alessandro Caproni via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildfires and carbon storage

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Forests are known to be a key natural solution to the increasing amounts of carbon dioxide in the atmosphere.  For this reason, there are widespread efforts to plant more trees around the world and to prevent increasing deforestation for development and agriculture.  But a new study has highlighted the fact that wildfires in the western US are degrading the potential for forests to help curb climate change.

The study has established a baseline for how much carbon is currently stored in Western forests, how that amount is changing, and how fires and droughts are affecting the ability of the forests to mitigate climate change.

The study made use of survey data collected by the US Forest Service to estimate how much carbon is stored in 19 ecoregions across the West.  These ecoregions range from hot and dry areas in the Southwest to the wet and cool regions of the Pacific Northwest.

The study reveals that the carbon stored in living trees declined across much of the Western US between 2005 and 2019.  Carbon stored in dead trees and woody debris increased.  These things do not provide long-term carbon storage.  Instead, they release it back into the atmosphere through decomposition or combustion in forest fires.

The increasing frequency and intensity of wildfires, especially since 2020, indicate that the decline in live carbon stored in the forests will become increasingly pronounced.  The result, according to the study’s authors, is that we cannot rely on increasing carbon storage in Western US forests.  It may be possible to increase the stability of carbon storage in the forests with mechanical thinning and prescribed burning, but the carbon carrying capacity of those forests is not likely to be what is needed.

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Forest carbon storage has declined across much of the Western US, likely due to drought and fire

Photo, posted July 25, 2021, courtesy of Felton Davis 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

Solar forests

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Forests are one of the most iconic symbols of the power and diversity of nature but beyond that, their thick vegetation is crucial to the stability and balance of the Earth’s climate.  This is because the photosynthesis that powers the growth of plants removes carbon dioxide from the air.  Cutting down forests – especially the evergreen forests of the tropics – has played a significant role in the increasing climate crisis.  For this reason, many environmental initiatives focus on restoring destroyed forests and planting new trees.

But the truth is, even if we were to cover the entire surface of the planet with trees, there would still not be enough photosynthesis going on to absorb the huge surplus of carbon dioxide that people have been pumping into the atmosphere for the past 150 years.

A study by the Weizmann Institute of Science in Israel looked at the impact of erecting fields of dark covered solar panels – so-called solar forests – that would generate electricity, thereby replacing power stations that use fossil fuels.  But dark fields absorb heat which eventually returns to the atmosphere.

The question is:  what is the best use of a plot of land in terms of the effect on the climate?  Planting a forest or erecting fields of solar panels?

The answer depends on where the land is.  In arid environments, building solar farms is far more effective and practical than planting forests.  But in humid places, forests currently absorb close to a third of humanity’s annual carbon emissions. 

The study concludes that combining planting and rehabilitating forests in humid regions and erecting fields of solar panels in arid regions is the most effective strategy.

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The Solar Forest

Photo, posted December 27, 2015, courtesy of Gerry Machen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The importance of Alaska’s National Forests

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The world’s forests play a crucial role in taking carbon out of the atmosphere and mitigating the effects of climate change.  An analysis of U.S. national forests shows that two southern Alaskan forests are key to meeting climate and biodiversity goals.

The Tongass Forest in Alaska is America’s largest national forest, encompassing 16.7 million acres.  Alaska’s Chugach Forest is the country’s second largest at just under 7 million acres.  These two forests are not only the largest national forests, they are also the most intact. 

A study by researchers at the Oregon State University College of Forestry looked at 152 national forests and compared them in terms of carbon density and accumulation, total biomass carbon stocks, habitat for eagles, bears, and wolves, and landscape integrity – which is the extent of modification by human activity.  According to the study, almost 31% of all high-landscape-integrity area found in national forests is in the Tongass and Chugach forests.  The Tongass alone represents over 25%.

These forests are cool and wet.  Their carbon stocks are only minimally affected by wildfire, unlike many other forests in the lower 48 states.  Given the size and stability of the two forests, protecting them is a high priority for making it possible to meet global goals relating to climate and diversity of species.

Ecosystems remove about 30% of all the carbon dioxide humans put into the atmosphere and intact forests with high carbon density do most of that work.  Protecting Alaska’s forests is crucial.

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Southern Alaska’s national forests key to meeting climate, conservation goals, OSU study shows

Photo, posted August 4, 2014, courtesy of Jeff Canon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and ecosystems

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Wildfires are a natural phenomenon.  They have occurred long before there were people around.  Ecosystems adapt to fires and some species can benefit from them or even depend upon them.  But in recent times, fires have been intensifying and increasing in frequency and they are beginning to outstrip nature’s ability to bounce back from them.

So-called megafires – ones that dwarf typical wildfires in size – have an immediate ecological toll.  They kill individual plants and animals that might have survived smaller fires. 

Over millennia, many species of plants and animals have evolved to adapt to periodic fires.  They are especially sensitive to smoke and take protective action in a timely fashion. Others take advantage of food sources that arise when trees burn.

But even species that capitalize on burned-out areas of forests require oases of healthy woodland for at least part of their activities.  When fires are too widespread, such oases are too few and far between.

Animals that survive fires must find food, water, and shelter in the aftermath.  And all air-breathing animals are going to be impacted by smoke exposure because the chemicals in smoke are toxic to them as well as to people.

In places like Canada’s Northwest Territories, repeated fires have transformed some forests, eliminating dominant tree species and replacing them with others whose light seeds were carried on the wind.

Scientists have estimated that increased global fire activity could push more than 1,000 threatened plant and animal species closer to extinction.  Changing fire patterns are transforming landscapes and utterly remaking ecosystems.

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How Megafires Are Remaking the World

Photo, posted December 19, 2022, courtesy of Brian Pippin/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Top Fish Predators And Climate Change | Earth Wise

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Climate change is taking its toll on forests, farms, freshwater sources, and the economy, but ocean ecosystems remain the epicenter of global warming.  In fact, oceans have absorbed more than 90% of the excess heat from greenhouse gas emissions since the 1970s.

As a result, many marine fish species are responding to ocean warming by relocating towards the poles.  According to new research recently published in the journal Science Advances, climate change is causing widespread habitat loss for some of the ocean’s top fish predators, driving these species northward.

The research team studied 12 species of highly migratory fish predators, including sharks, tuna, and billfish, such as marlin and swordfish, inhabiting the Northwest Atlantic Ocean and the Gulf of Mexico.  These two regions are undergoing rapid changes in sea surface temperatures, and are among the fastest warming ocean regions on earth.

The research, which was led by researchers from Woods Hole Oceanographic Institution in Massachusetts, with collaboration from San Diego State University, NOAA, and several other U.S. institutions, found that most species will encounter widespread habitat losses by 2100.  Some species could lose upwards of 70% of suitable habitat by that year.  Areas offshore of the Southeast United States and Mid-Atlantic coasts were identified as likely hotspots of multi-species habitat loss. 

According to the researchers, strategies for managing fish have historically been static. But marine systems need to be treated as dynamic and changing.  This study helps provide the scientific data needed for marine conservation and fisheries management efforts.

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Top fish predators could suffer wide loss of suitable habitat by 2100 due to climate change

Photo, posted March 18, 2015, courtesy of Kenneth Hagemeyer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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