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More eco-friendly desalination

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There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced.  Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment.  There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic.  The process called electrodialysis uses electrified membranes to concentrate salts. 

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors.  Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes.  Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis.  The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power.  The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente 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 Colorado River crisis

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The Colorado River serves nearly 40 million people in seven U.S. states and Mexico.  It provides water for 5 million acres of farmland.  Increasing demand from growing populations, damming, diversion, and drought have been draining the Colorado at alarming rates.  This critical resource supports countless economies, communities, and ecologies stretching from the Rocky Mountains to the Gulf of California.  The Colorado River essentially has made the cities of Las Vegas, Los Angeles, Denver, and Phoenix possible.

How the water of the Colorado is distributed is determined by an agreement that is over 100 years old:  the Colorado River Compact.  It was made at a time when people thought there was more water than really was there.  And at the time, no one thought that the seven states would need to use the water they were allocated down to the last drop.

There have been various measures over the years to conserve water from the Colorado River, including the Colorado River Interim Guidelines in 2007.  Those guidelines will expire in 2026 and negotiations are beginning to take place among the many stakeholders scrambling for water rights.  Apart from the seven U.S. states and Mexico, there are 30 tribal nations involved.  Collaborative governance is complicated when it crosses multiple jurisdictions with their own laws and legal precedents.  The goal is to put in place a new agreement to protect the Colorado River.

Rapidly-growing populations in major cities, a 20-year megadrought, and historically low water levels in America’s two largest reservoirs have put enormous pressure on the Colorado River.  Creating a plan to protect the lifeblood of the American West is essential.

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Addressing the Colorado River crisis

Photo, posted June 18, 2022, courtesy of Jeff Hollett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The East Coast is sinking

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio

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

Record high emissions

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The world is adding solar and wind power to the grid.   We are driving more and more electric cars.  Countries are pledging to cut back fossil fuel use.  There are highly visible international conferences on the climate crisis.   But despite all of these things, global carbon emissions from fossil fuels have risen once again in 2023, reaching all-time record high levels of more than 40 billion tons, about 1.1% more than the previous year.

In some places, including Europe and the U.S., fossil fuel CO2 emissions are falling, but globally, they are still rising.  Emissions continued to increase in India and China.  Global action to cut fossil fuel use is not happening fast enough to prevent the increasingly dangerous effects of climate change.

Global CO2 emissions include both the contributions of fossil fuel use and the effects of land use change.  Adding the two together, in 2023 the total was about 45 billion tons, basically unchanged from last year. 

Adding insult to injury are the emissions from fires.  The extreme wildfire seasons in Canada, Australia, and other places have contributed CO2 emissions much larger than historical averages.

About half of all the carbon dioxide emitted on Earth is absorbed by carbon sinks on land and the oceans.  The other half remains in the atmosphere, where levels are now averaging 419 parts per million, 51% above pre-industrial levels.

Current efforts are simply not profound enough or widespread enough to put global emissions on a downward trajectory.  Some climate policies in some places are proving effective, but much more needs to be done.

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Fossil CO2 emissions at record high in 2023

Photo, posted December 18, 2013, courtesy of Steve Nelson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ending plastic separation anxiety

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Petroleum-based plastics are one of the biggest environmental problems we face.  They mostly end up in landfills – or worse, in the oceans and elsewhere in the environment – and they basically don’t decompose over time.  Bio-based plastics were invented to help solve the plastic waste crisis.  These materials do break down in the environment providing a potential solution to the problem.  But it turns out that they can actually make plastic waste management even more challenging.

The problem is that bioplastics look and feel so similar to conventional plastics that they get mixed in with the petroleum-based plastics rather than ending up in composters, where they can break down as designed.

Mixtures of conventional and bioplastics end up in recycling streams where they get shredded and melted down, resulting in materials that are of very poor quality for making functional products.  The only solution is to try to separate the different plastics at recycling facilities, which is difficult and expensive to do.

Scientists at Lawrence Berkeley National Laboratory, the Joint BioEnergy Institute, and the incubator company X have invented a simple “one pot” process to break down mixtures of different types of plastic using naturally derived salt solutions and specialized microbes and then produce a new type of biodegradable polymer that can be made into fresh commodity products.

The team is experimenting with various catalysts to find the optimum way to break down polymers at the lowest cost and are modeling how their processes can work at the large scales of real-world recycling facilities. Chemical recycling of plastics is a hot topic but has been difficult to make happen economically at the commercial scale.

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Putting an End to Plastic Separation Anxiety

Photo, posted November 28, 2016, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Food and the climate crisis

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Agriculture is a major part of the climate problem and remains one of the hardest human activities to decarbonize.  It’s responsible for approximately 25% of global greenhouse gas emissions. 

Many experts contend that alternative food sources – like insect farming and seaweed aquaculture – are part of the solution.  Additionally, expanding production of climate resilient food crops, including quinoa, kernza, amaranth, and millet, likely also have a role to play. 

But according to a new study led by researchers from the University of California – Irvine, another solution to this problem may be to eliminate farms altogether.  In the study, which was recently published in the journal Nature Sustainability, the research team explored the potential for wide scale synthetic production of dietary fats through chemical and biological processes.  The materials needed for this method are the same as those used naturally by plants: hydrogen (in water) and carbon dioxide (in the air).   

The research team highlighted some of the potential benefits of farm-free food, including reduced water use, less pollution, localized food production, and less risk to food production from weather. 

Cookies, crackers, chips, and many other grocery products are made with palm oil, a dietary fat that continues to be a major driver of deforestation around the world.  However, it remains to be seen how consumers would react if the oil used to bake their cookies came from a food refinery up the road instead of a palm plantation in Indonesia.     

According to the researchers, depending on food refineries instead of tropical plantations for dietary fats could mitigate lots of climate-warming emissions while also protecting land and biodiversity.

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UC Irvine-led science team shows how to eat our way out of the climate crisis

Photo, posted July 15, 2008, courtesy of Quinn Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Groundwater Crisis | Earth Wise

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The majority of U.S. drinking water systems rely on groundwater, as do America’s farms.  Even though groundwater is a crucial resource for the country, there is no central oversight or even monitoring of its status across the country.  The health of the country’s aquifers is difficult to gauge.

The New York Times spent months amassing data from 80,000 wells across the country by reaching out to federal, state, and local agencies nationwide.

The survey found that 45% of the wells examined showed a statistically significant decline in water levels since 1980.  Forty percent of the sites reached record-low water levels over the past 10 years, with last year the worst yet.

Over pumping is the biggest problem.  State regulations tend to be weak and there is no federal oversight.  The warming climate reduces snowpack, which means less water in rivers, increasing the need to tap into groundwater.  Warmer weather means thirstier plants, increasing the demand for water.

It is a nationwide problem, not just one in the drought-ridden West.  Arkansas, which produces half of the country’s rice, is pumping groundwater twice as fast as nature can replace it.  Three-quarters of Maryland’s wells have seen substantial drops in water levels.

As groundwater is pumped out, the empty space can collapse under the weight of the rock and soil above it, permanently diminishing the capacity for future groundwater storage.

There are likely to be parts of the U.S. that run out of drinking water and groundwater depletion threatens America’s status as an agricultural superpower. Objectively, the status of American groundwater is a crisis that threatens the long-term survival of communities and industries that depend on it. 

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Five Takeaways From Our Investigation Into America’s Groundwater Crisis

Photo, posted July 25, 2009, courtesy of Chris Happel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cryo Conservation | Earth Wise

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Recent studies have shown that there has been a 69% decline in global animal populations since 1970.  There is a biodiversity crisis in the world.  In the face of this situation, there is a growing interest in using cold storage to preserve genetic samples taken from animals threatened with extinction.

Just as egg-freezing is used to preserve human fertility for a later date, the cryogenic freezing of genetic material from animals could be important in reducing species extinctions.  Living cell banks – also known as cryobanks – could preserve genetic materials from animals that include skin cells, embryos, semen, and live tissues.  These materials could be cultured and used for various applications including DNA extraction, assisted reproduction, ensuring genetic diversity in animal populations, and potentially reintroducing species back into their natural habitats.

There is a facility called the Frozen Zoo at the San Diego Wildlife Alliance which has genetic material from 965 different species, including 5% of the vertebrates currently listed as threatened on the IUCN Red List.  Further sampling from zoos and aquariums could increase that representation to almost 17%.

Genetic samples of 50% of the species currently listed as extinct in the wild are already represented in the Frozen Zoo.  Further sampling from the zoological community could increase this number to 91%.  This could provide a critical lifeline for these species that are on the brink of extinction.  As wildlife populations continue to decline around the world, it is more critical than ever to collect and preserve genetic samples from threatened species.

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Cryo conservation – a cool solution to saving species from extinction

Photo, posted September 30, 2018, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A New Deep-Sea Reef In The Galapagos | Earth Wise

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Like in many other places around the world, ocean warming has mostly destroyed the shallow-water reefs in the Galapagos Islands.  The islands are some of the most carefully protected places in the world, but they can’t escape the effects of a warming planet.

Recently, however, scientists have discovered a healthy, sprawling coral reef hidden deep under the sea in the Galapagos.  More than 1,300 feet underwater, the reef extends for several miles along the ridge of a previously unknown volcano in the Galapagos Marine Preserve.

The reef is pristine and is teeming with all sorts of marine life including pink octopus, batfish, squat lobsters, and a variety of deep-sea fish, sharks, and rays.

The expedition that discovered the new reef was led by the University of Essex in the UK.  Prior to this discovery, scientists thought that coral reefs were all but gone from the Galapagos.  A period of ocean warming in 1982 through 1983 wiped out more than 95% of the corals in the archipelago.  Only a few reefs in shallow waters remained.  The newly discovered reefs are sheltered deep under the sea and would have been protected from the deadly heat.

According to the scientists from the expedition, the newly discovered reef potentially has global significance because it represents a site that can be monitored over time to see how such a pristine habitat evolves with the ongoing climate crisis.  Reefs like this are clearly very old because coral reefs take a long time to grow. Finding this one means that it is likely that there are more healthy reefs across different depths that are waiting to be discovered.

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Pristine Deep-Sea Reef Discovered in the Galápagos

Photo, posted March 28, 2009, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Storms And The Megadrought | Earth Wise

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California experienced its wettest 10-day period in 25 years as a result of a series of storms driven by atmospheric rivers in January.  The Rocky Mountains got buried in snow from the same weather pattern.   For the drought-stricken West, the storms were good news.  But they are not the cure for what’s been ailing the region.

In California, the snowpack in the Sierra Nevada mountains has been greatly enhanced, containing twice as much snow as is considered average for this time of year.  Without a doubt, it will reduce the impact of the drought that has plagued the state for 23 years.  But one big storm or even a series of them is not enough to undo years of minimal precipitation and rising temperatures.  Many of the states’ largest reservoirs remain well below historical averages despite the record-breaking rain.  It would take several wet years to really allow the state to recover from the drought.

The snowfall in the Rockies is crucial because it is the source of more than two-thirds of the water in the Colorado River.  The Colorado River is the water lifeline for 40 million people from Wyoming to Mexico.

The ongoing shrinking of the Colorado River is a crisis that has created massive problems for the multibillion-dollar agriculture industry and for many large cities, including Denver, Phoenix, Salt Lake City, Las Vegas, and Los Angeles.  Two of the nation’s largest reservoirs – Lake Mead and Lake Powell – are filled by the Colorado River.  The historic low levels of these reservoirs have threatened the functioning of hydropower facilities that provide electricity to millions of people.

The January storms were good news for the West, but its problems are not over.

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This Winter’s Rain and Snow Won’t be Enough to Pull the West Out of Drought

Photo, posted September 18, 2022, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fusion Power And The Climate Crisis | Earth Wise

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In December, the Department of Energy announced that scientists at Lawrence Livermore National Laboratory in California had achieved a breakthrough in nuclear fusion technology.  Fusion is the process by which the sun generates energy.  If we had the means to produce nuclear fusion in a controlled fashion, it would be an almost limitless source of clean energy.

Scientists have been trying to develop controllable fusion since the advent of the hydrogen bomb in the 1950s.  H-Bombs are basically uncontrollable fusion.

There are massive experiments under development around the work seeking the means to create and control fusion.  There are multi-billion-dollar projects such as the ITER tokamak project in southern France, that have been ongoing for decades.  Colossal equipment is required to produce the temperatures of millions of degrees needed to fuse hydrogen atoms into helium atoms.

The Livermore project uses 192 powerful laser beams to vaporize a tiny pellet and provide the energy required to initiate fusion. The breakthrough is that the experiment released more energy than the lasers put in.  This was the first time a fusion experiment produced a net gain of energy.

Is fusion the solution to de-carbonizing the energy system?  Perhaps someday it might be.  However, even the most optimistic fusion researchers believe it will be at least another decade before even the experimental fusion systems around the world can reliably produce energy and the efforts will cost untold billions of dollars. 

The world cannot wait for fusion power to save the day.  The focus must remain on currently available renewable energy technologies if we are to achieve the necessary emission reductions in time to prevent the worst effects of climate change.

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Can Fusion Solve the Climate Crisis?

Photo, posted July 29, 2010, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The State Of The Birds | Earth Wise

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio

The Living Planet Index | Earth Wise

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The World Wildlife Fund and the Zoological Society of London recently published the latest Living Planet Index, which is designed to measure how animal populations are changing through time.  The purpose is to provide an assessment of the health of ecosystems and the state of biodiversity.

The LPI only looks at the population of vertebrates:  birds, mammals, reptiles, amphibians, and fish.  The latest survey looked at how populations have changed between 1970 and 2018.  The results are that populations of these animal groups have declined by an average of 69% over that 48-year period.

This result highlights a very real and very severe crisis of biodiversity loss.  However, it does not mean that there are 2/3 fewer animals today than 48 years ago.  The way the index is calculated is to look at the changes in individual populations of over 5,000 different species.  Then these individual relative declines are averaged to get the result.  

There are shortcomings in the LPI.  For example, individual species that have seen massive population declines will bring the average down.  But even removing the outliers both of a negative and a positive impact does not dramatically change the result.

There is no perfect indicator for biodiversity and ecosystem health.  The Living Planet Index is nonetheless a useful metric and indicates that many species around the world are in decline.  Policymakers and environmental advocates need to make decisions about conservation and protection measures and this index is one tool they can use.

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There’s a frightening new report about wildlife declines. But many are getting the story wrong.

Photo, posted October 12, 2019, courtesy of Visit Rwanda via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rewilding The American West | Earth Wise

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Oregon State University scientists have proposed a series of management changes for western federal lands aimed at re-establishing ecosystems there.  Their proposal would result in more gray wolves and beavers in nearly 200,000 square miles of federal lands in 11 states.

In each of those states, the researchers identified areas containing prime wolf habitat.  Gray wolves were hunted to near extinction in the West but have been gradually reintroduced in some areas starting in the 1990s.  Wolf restoration offers significant ecological benefits by helping to naturally control the population of grazing animals such as elk.  This in turn facilitates the regrowth of vegetation species such as aspen, which ultimately supports diverse plant and animal communities.

Beaver populations, which used to be robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many areas.  By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and settlement retention, maintain water flows during droughts, and increase carbon sequestration.

According to the researchers, the biggest threat to these western lands is livestock grazing, which has degraded ecosystems to a great extent.  They recommend the removal of grazing on about 30% of the federal lands being used for that purpose and instead would have rewilding efforts go on. 

The American West is going through a period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires, and loss of biodiversity.  Rewilding is a way to reestablish long-standing ecosystems.

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More wolves, beavers needed as part of improving western United States habitats, scientists say

Photo, posted October 1, 2020, courtesy of Tina DaPuglet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Resilient Microalgae | Earth Wise

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The plight of the world’s coral reefs has been a growing environmental crisis for many years.  Coral reefs provide sustenance and income to half a billion people, are major tourist attractions, protect coastlines, and are important centers of biodiversity.   And because of the warming climate as well as other effects of human activity, more than half of the world’s coral reefs are under stress.

The primary threat is coral bleaching, which is the disruption of the symbiotic relationship between coral polyps (which are tiny animals) and the heavily pigmented microalgae that live within the coral structures and provide most of the energy for the polyps. When corals are stressed, often because water temperatures are too high, they expel the microalgae within them.  The structures then become transparent, leaving only the white skeletal corals.  Bleached corals aren’t dead, but they are at great risk of starvation and disease until and unless new symbiont algae are acquired.

A new study by scientists at Uppsala University in Sweden investigated how different species of coral symbiont algae react to temperature stress.  They discovered differences among symbiont cells that enable the prediction of how temperature stress tolerant the cells are.  Such predictive ability could provide the means to identify and select more temperature-tolerant coral symbionts that could conceivably be introduced into coral host larvae in order to make corals more robust against climate change.

The research has a ways to go, but the new tools may help coral reef monitoring and increase the speed at which reef restoring efforts can create stocks of climate-resistant symbionts.

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Climate resilient microalgae could help restore coral reefs

Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reshaping Our Planet | Earth Wise

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Human activity – especially agriculture – has altered 70% of the land on our planet.  According to a new report from the United Nations, damage to the Earth’s lands has put the planet on “crisis footing”.

Our health, our economy, and our well-being depend on land.  The food we eat, the water we drink, and the air we breathe all rely on status of the land to at least some extent.

According to the report, up to 40% of the planet’s land is already degraded, affecting half of the people alive today.  At current rates, an additional area nearly the size of South America will be degraded by 2050.

Degradation of land occurs in various ways, including deforestation, desertification, and the loss of wetlands or grasslands.  All of these things are caused by human activities.  As forests, savannas, wetlands, and mangrove swamps are converted to agriculture or are lost to urban expansion, greenhouse gas emissions rapidly increase, adding to the effects of climate change.  The climate crisis, biodiversity loss, and land degradation are integrally linked.

Much of the blame for degraded landscapes is on humanity’s ever-expanding need for food and the modern farming systems that produce it.  The global food system is responsible for 80% of the world’s deforestation, 70% of freshwater use, and is the greatest driver of land-based biodiversity loss.  Modern agriculture has altered the face of the planet more than any other human activity.

The report urges efforts at restoration of land.  Restoration can take multiple forms, including planting forests and shrubs or grazing livestock and growing crops between trees instead of clearing existing forests.

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UN Report Says Humanity Has Altered 70 Percent of the Earth’s Land, Putting the Planet on a ‘Crisis Footing’

Photo, posted June 20, 2010, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Permafrost Thaw | Earth Wise

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We’ve talked about permafrost before.  It is the frozen soil, rock, or sediment piled up in the Arctic that has been there at least for two years but, for the most part, for millennia or even over a million years.  Permafrost holds the carbon-filled remains of vegetation and animals that froze before they could start decomposing.   Estimates are that there are nearly 2,000 billion tons of carbon trapped in Arctic permafrost.  To put that in perspective, annual global carbon emissions are less than 40 billion tons.

Keeping all that carbon frozen plays a critical role in preventing the planet from rapidly heating. The ongoing warming of the Arctic is causing the subsurface ground to thaw and release long-held carbon to the atmosphere.

Scientists from Europe and the US are working together to better track permafrost carbon dynamics.  They are trying to understand the mechanisms that lead to abrupt thaws in the permafrost that have taken place in some locations.  These rapid thawing events are not well understood.  Researchers are also studying the effects of the increasingly frequent wildfires in the Arctic on the permafrost.

Researchers are using satellites to better understand the effects climate change is having on the Arctic environment and how these changes, in turn, are adding to the climate crisis.  Permafrost cannot be directly observed from space, so that its presence has to be inferred from measurements like land-surface temperature and soil moisture readings.  Terrestrial observations are also necessary for understanding how greenhouse gases – both CO2 and methane – are being emitted from the Arctic.

Thawing permafrost is a ticking timebomb for the environment that demands the growing attention of the scientific community.

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Permafrost thaw: it’s complicated

Photo, posted January 24, 2014, courtesy of Brandt Meixell / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climbing To Escape The Heat | Earth Wise

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Colorado has warmed by nearly 3.5 degrees Fahrenheit since the 1980s because of human-caused climate change.   As a result, many mammal species have shifted uphill to escape the heat.

The golden-mantled ground squirrel is a popular sight among tourists in the Rocky Mountains.  It is one of the most photographed animals there as they pose on rocks near roadsides and in campgrounds.  According to University of Colorado research recently published in the journal Ecology, these squirrels have shifted their range upward by 659 feet.  The new study looked at the ground squirrels along with 46 other small mammals.  On average, these animals have shifted their range upward by more than 400 feet since the 1980s.

The researchers visited multiple sites in Colorado’s Front Range and San Juan mountains over the course of several years to collect records of the current ranges of these 47 animals. They then compared the findings from their surveys to over 4,000 historic records from collections dating back to the 1980s.

The researchers expected to see some changes, but not of the magnitude they observed.  For example, before 1980, the pygmy shrew was never detected above about 9,800 feet in elevation.  Today, its maximum extent is more than 11,800 feet.

Montane mammals – which are those who already live at higher elevations – have moved up an additional 1,100 feet on average.  If this trend continues, some animals and even entire communities may be pushed to the tops of mountains with nowhere else to go.  According to the researchers, the study paints a stark picture of a mountain range in crisis.

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Small mammals climb higher to flee warming temperatures in the Rockies

Photo, posted September 6, 2002, courtesy of Franco Folini via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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