Young aspen trees in Yellowstone are doing something they have not done in almost 100 years. Rather than sprouting and being eaten back to nubs by elk and bison, they're actually growing into tall, adult forest trees rising up towards the canopy.



This matters more than it might seem, because it shows what happens when a missing piece of an ecosystem returns.



<h2 class="wp-block-heading" id="h-yellowstone-aspens-and-elk">Yellowstone, aspens, and elk</h2>



In the 1920s, people <a href="https://www.yellowstone.org/wolf-project/" target="_blank" rel="noreferrer noopener">eliminated wolves in Yellowstone</a>. At the time, with limited scientific knowledge, managers believed it was the right thing to do.



<a href="https://www.earth.com/news/from-wolves-to-dogs-did-domestication-begin-without-human-help/">Without wolves</a>, elk herds grew very large. Elk love to eat aspen shoots - the tender young growth is highly palatable to them.



For roughly 70 years, elk browsed aspen sprouts down to stub height, and the trees couldn't grow. 



If you had walked through Yellowstone in the 1980s, you would have seen many tiny aspen shoots covering the ground, but almost no young trees gaining height. 



The forest's regeneration was stalled. Old trees died, and no new ones replaced them.



In 1995 and 1996, park managers reintroduced wolves into the <a href="https://www.earth.com/news/yellowstone-supervolcano-eruption-study-sparks-new-debate-on-where-and-when-it-will-erupt/">Yellowstone Park ecosystem</a>. Scientists hoped and wondered whether this would change anything for the trees.



<h2 class="wp-block-heading" id="h-why-aspen-matter-to-yellowstone">Why aspen matter to Yellowstone</h2>



Aspen groves provide habitat for many species. Birds nest in them. Beavers eat the bark and use the wood for dams. Butterflies and moths lay eggs on the leaves. 



Their canopy admits enough light for wildflowers and shrubs to grow beneath. When it rains, aspen groves hold water in the soil better than some other forest types.



In short, when aspen return, dozens of other species benefit. More trees support more insects, which in turn support more birds, enriching the ecosystem.



<h2 class="wp-block-heading" id="h-checking-the-trees-three-decades-later">Checking the trees three decades later</h2>



<a href="https://fwcs.oregonstate.edu/users/luke-painter" target="_blank" rel="noreferrer noopener">Luke Painter</a>, an ecologist at <a href="https://oregonstate.edu/" target="_blank" rel="noreferrer noopener">Oregon State University</a>, sought clear answers. His team returned to 87 aspen stands across Yellowstone that scientists had previously surveyed. 



They measured thousands of young trees, looked for bite marks, and counted how many stems were tall enough that elk could no longer reach the tips.



About a third of these stands now have many tall young aspens pushing toward the canopy. 



"About 26 of the 87 aspen stands we examined had large numbers of tall saplings throughout, a remarkable change from the 1990s when surveys found none at all," Painter said.



<h2 class="wp-block-heading" id="h-why-wolves-matter-to-yellowstone-aspens">Why wolves matter to Yellowstone aspens</h2>



Breaking it all down, the conclusions of this study are pretty simple. 



<a href="https://www.earth.com/news/wolves-move-pups-across-mountains-to-adapt-to-climate-pressure/">Wolves hunt elk</a>. When wolves came back, two things happened. First, elk numbers declined from unusually high levels. Second, elk changed their behavior. They spent less time in the same areas feeding.



With fewer elk and shorter feeding bouts, more aspen shoots survived long enough to exceed the browsing zone - about six to seven feet high. 



Once a sapling reaches that height, elk cannot easily reach the growing tip. The tree continues to grow.



"The reintroduction of large carnivores has initiated a recovery process that had been shut down for decades," Painter explained.



Scientists call this a <a href="https://www.nature.com/scitable/knowledge/library/trophic-cascades-across-diverse-plant-ecosystems-80060347/" target="_blank" rel="noreferrer noopener">trophic cascade</a> - when adding or removing one species causes changes that ripple through the whole system.



<h2 class="wp-block-heading" id="h-some-places-recover-others-don-t">Some places recover, others don't</h2>



Unfortunately, not every aspen stand has recovered yet. Some valleys still have many short, heavily browsed shoots, because it's not only elk eating them anymore. 



<a href="https://www.earth.com/news/yellowstones-iconic-bison-have-merged-into-a-single-herd/">Bison herds have grown</a>, and bison browse on aspen as well. They are strong enough to break young trees. 



"Increasing numbers of bison may be emerging as a new constraint to aspen in some areas," Painter confirmed.



Additionally, winter snow depth varies; droughts stress trees; bears and mountain lions also hunt elk; and hunting outside the park influences elk distribution. 



All of these factors interact, which is why some sites show strong recovery, others show moderate recovery, and a few have changed very little.



The key pattern is that places with many tall saplings experience little browsing, and aspen groves that remain popular eating grounds today stay short. 



This fact is the strongest indication that tree recovery is linked directly to wolf presence, not solely to weather or soil conditions.



<h2 class="wp-block-heading" id="h-proof-in-the-measurements">Proof in the measurements</h2>



Painter's team did not rely on casual observation. They used the same methods as earlier researchers, measuring the same plots. 



They counted recruitment - when young trees surpass browsing height and begin progressing toward maturity. This measure is crucial. Sprouts are insufficient if they never grow; without recruitment, the forest cannot replace itself.



The results are robust. After being stalled for most of a century, Yellowstone's aspens are increasing in height. In recovering stands today, you will see saplings - six, eight, or ten feet tall - that were not present in the 1990s.



<h2 class="wp-block-heading" id="h-the-future-of-yellowstone-s-aspens">The future of Yellowstone's aspens</h2>



"This is a remarkable case of <a href="https://www.earth.com/news/giant-viruses-found-in-yellowstones-hot-springs-may-be-near-the-root-of-all-life-on-earth/">ecological restoration</a>," Painter concluded. "Wolf reintroduction is yielding long-term ecological changes contributing to increased biodiversity and habitat diversity."



Trees grow slowly, so even with wolves restored, it will take decades for these young aspens to form a full-grown forest. 



Some areas might never fully recover if bison numbers continue to rise or if the climate becomes too hot and dry.



Thanks to the work of Painter and his team, scientists are now certain that restoring the Yellowstone predator has restarted aspen forest regeneration. Not everywhere and not perfectly, but enough to be measured, creating hope for the future.



The full study was published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0378112725004499?via%3Dihub" target="_blank" rel="noreferrer noopener">Forest Ecology and Management</a>.



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Yellowstone's aspen trees are growing again thanks to the reintroduction of wolves

Young aspen trees in Yellowstone are doing something they have not done in almost 100 years. Rather than sprouting and being eaten back to nubs by elk and bison, they're actually growing into tall, adult forest trees rising up towards the canopy. This matters more than it might seem, because it shows what happens when a missing piece of an ecosystem returns. Yellowstone, aspens, and elk In the 1920s, people eliminated wolves in Yellowstone. At the time, with limited scientific knowledge, managers believed it was the right...

Cell movement is a critical process during the body's development, as differentiated cells must make their way to specific tissues. Cells also mobilize to repair wounds and fight <a href="http://www.earth.com/news/severe-covid-19-infections-may-be-caused-by-overactive-immune-cells/">infections</a>. Meanwhile, cancer cells move to nearby blood vessels to spread to other parts of the body.

The speed of cell movement, or cell velocity, is controlled by how sticky the surface is beneath it. However, the exact mechanisms underlying cell movement and velocity have remained a mystery for decades. 

To investigate, experts at the <a href="https://www.mdc-berlin.de/">Max Delbrück Center for Molecular Medicine in the Helmholtz Association</a> (MDC) developed a new mathematical model. The researchers have finally captured, for the first time, the precise mechanics and forces involved in cell movement.

"The mathematical model we developed can now be used by researchers to predict how different cells will behave on various substrates," said study co-lead author Professor Martin Falcke. "Understanding these basic movements in precise detail could provide new targets to interrupt tumor metastasis."

In collaboration with experimental physicists at Ludwig Maximilians Universität München, a team of theoretical physicists at MDC tracked the speed of more than 15,000 cancer cells as they moved along narrow lanes on a sticky surface. The stickiness of the surface alternated between low and high, which allowed the experts to observe what happens as a cell transitions between dynamic stickiness levels like those present in the human body.

Professor Falcke and PhD student Behnam Amiri used the large dataset to develop a mathematical equation that represents the factors involved in cell movement.

"Previous mathematical models trying to explain cell migration and motility are very specific, they only work for one feature or cell type," said Amiri. "What we tried to do here is keep it as simple and general as possible."

The model not only matched the data gathered at LMU, but was also validated by measurements of various other cell types taken over the past 30 years. "This is exciting," said Professor Falcke. "It's rare that you find a theory explaining such a large spectrum of experimental results."

During movement, a cell pushes out its membrane in the direction it is traveling while expanding an internal network of actin filaments. The cell peels off its back end, and the speed at which this occurs depends on adhesion bonds between the cell and the surface beneath it. 

The actin network needs friction to mobilize the cell. This means that when there are no adhesive bonds, the cell struggles to move because the actin network does not have anything to push off against.

"When you are on ice skates you cannot push a car, only when there is enough friction between your shoes and the ground can you push a car," explained Professor Falcke.

More friction is created as the number of bonds increase, and the cell can generate more force. The cell can then move faster, until the point when it is too sticky to swiftly pull off its back end, and the cell slows down again. 

The researchers investigated what happens when the front and back ends of the cell experience different levels of stickiness. They were especially interested in what happens when it is stickier under the back end of the cell than the front. Would the cell get stuck if it cannot generate enough force to pull off the back end? The experts determined that the cell may get slowed way down, but does not get stuck. 

Professor Falcke said the most challenging part was to wrap his mind around the fact that this mechanism works only with friction forces, because there is nothing for the cell to firmly latch onto. The friction-like forces are what allows the cell to keep moving, even when bonds are stronger in the back than in the front. In this case, the cell slowly peeled itself off like scotch tape. 

"Even if you pull just a little with a weak force, you are still able to peel the tape off - very slowly, but it comes off," said Professor Falcke. "This is how the cell keeps itself from getting stuck."

The findings provide new insight for developmental biology, as well as for potential cancer treatments. Currently, the team is investigating how cells move in two dimensions, including how they make hard right and left turns and U-turns.

The study is published in the journal <a href="https://www.pnas.org/">Proceedings of National Academy of Science</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The precise mechanics of cell movement are finally revealed

Cell movement is a critical process during the body's development,...

As Earth's temperatures continue to rise, the tropical rain belt is expected to make a permanent shift to the north. A new study from <a href="https://uci.edu/">UC Irvine</a> confirms that <a href="http://www.earth.com/news/the-worlds-oceans-have-become-less-resilient-to-climate-change/">climate</a> change will alter the position of the rain belt, but reveals that the changes will be regionally inconsistent.

The interdisciplinary research team - consisting of environmental engineers, Earth system scientists, and <a href="https://www.earth.com/news/collecting-dna-from-rivers-uncovers-biodiversity/" target="_blank" rel="noopener">data science experts</a> - warns that the uneven shifting of the tropical rain belt could threaten food security for billions of people.

The tropical rain belt, a band of heavy rainfall near the equator, is known to migrate northward and southward with the seasonal movement of the sun. 

The new study shows that the consistency of these annual migration patterns will be disrupted by climate change, and not all parts of the tropics will be affected equally.

For example, the rain belt will move north in parts of the Eastern Hemisphere, and south in parts in the Western Hemisphere.

According to the study authors, a northward shift of the tropical rain belt over eastern Africa and the Indian Ocean will result in future increases of drought stress in southeastern Africa and Madagascar. This climate pattern will also amplify flooding in southern India. 

Furthermore, as a result of the rain belt moving southward over the eastern Pacific and Atlantic Oceans, Central America will experience more intense drought conditions.

"Our work shows that climate change will cause the position of Earth's tropical rain belt to move in opposite directions in two longitudinal sectors that cover almost two thirds of the globe, a process that will have cascading effects on water availability and food production around the world," explained study lead author Antonios Mamalakis.

For the investigation, the experts analyzed computer simulations from 27 advanced climate models. They measured the tropical rain belt's response to a scenario in which greenhouse gas emissions continue to rise through the end of the century.

Mamalakis said the sweeping shift detected in his work was disguised in previous modeling studies that provided a global average of the influence of climate change on the tropical rain belt. His team was able to predict the drastic upcoming changes by isolating the response in the Eastern and Western Hemisphere zones.

"In Asia, projected reductions in aerosol emissions, glacier melting in the Himalayas and loss of snow cover in northern areas brought on by climate change will cause the atmosphere to heat up faster than in other regions," said study co-author James Randerson. 

"We know that the rain belt shifts toward this heating, and that its northward movement in the Eastern Hemisphere is consistent with these expected impacts of climate change."

The weakening of the Gulf Stream current and deep-water formation in the North Atlantic is likely to have the opposite effect, causing a southward shift in the tropical rain belt across the Western Hemisphere, explained Randerson.

"The complexity of the Earth system is daunting, with dependencies and feedback loops across many processes and scales," said study co-author Professor Efi Foufoula-Georgiou.

"This study combines the engineering approach of system's thinking with data analytics and climate science to reveal subtle and previously unrecognized manifestations of global warming on regional precipitation dynamics and extremes."

The study is published in the journal <a href="https://www.nature.com/nclimate">Nature Climate Change</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Drastic changes ahead for the Earth's tropical rain belt

As Earth's temperatures continue to rise, the tropical rain belt...

A new study from the <a href="https://www.tsukuba.ac.jp/en/">University of Tsukuba</a> has identified a group of neurons in the brain that restrict movement during REM sleep. This new understanding of how the <a href="http://www.earth.com/news/disagreements-demand-more-space-in-the-brain/">brain</a> paralyzes the body throughout REM sleep may ultimately provide a target for disorders like narcolepsy and cataplexy.

During REM sleep, our eyes move back and forth as we dream, but our bodies remain still. This protective state of temporary paralysis of the arms and legs, known as atonia, does not occur in people with REM sleep behavior disorder. 

Instead of lying still, people with REM sleep behavior disorder experience muscle movement. These individuals may stand up, jump around, and even yell or punch as they are dreaming.

The Tsukuba team set out to identify the neurons in the brain that promote atonia. Using a mouse model, the researchers found a specific group of neurons located in the ventral medial medulla that were the most likely candidates. These particular neurons receive input from another brain region called the sublaterodorsal tegmental nucleus (SLD).

"The anatomy of the neurons we found matched what we know," explained study lead author Professor Takeshi Sakurai. "They were connected to neurons that control voluntary movements, but not those that control muscles in the eyes or internal organs. Importantly, they were inhibitory, meaning that they can prevent muscle movement when active." 

When the researchers blocked the input to these neurons, the mice started moving during their sleep, just like someone with REM sleep behavior disorder.

People with narcolepsy can suddenly fall asleep at any time during the day, even in mid-sentence. Individuals with cataplexy suddenly lose muscle tone and collapse as if they are in a state of REM sleep when they are actually awake

Professor Sakurai and his team theorized that the special neurons they identified were related to both disorders. To investigate, the experts used a mouse model of narcolepsy in which cataplexic attacks could be triggered by chocolate. 

"We found that silencing the SLD-to-ventral medial medulla reduced the number of cataplexic bouts," said Professor Sakurai.

The experiments revealed that these special circuits control muscle atonia in both REM sleep and cataplexy. 

"The glycinergic neurons we have identified in the ventral medial medulla could be a good target for drug therapies for people with narcolepsy, cataplexy, or REM sleep behavior disorder," said Professor Sakurai. 

"Future studies will have to examine how emotions, which are known to trigger cataplexy, can affect these neurons."

The study is published in the Journal of <a href="https://www.jneurosci.org/">Neuroscience</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

How the brain paralyzes the body during REM sleep

A new study from the University of Tsukuba has identified...

A groundbreaking study from the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a> is providing new insight into the long-term <a href="http://www.earth.com/news/gut-health-may-protect-you-from-severe-covid-19/">health</a> benefits of breastfeeding. The researchers have discovered why breastfed babies have vastly improved immune systems, get sick less often, and recover more quickly. 

Breastfeeding has been linked to better health from infancy to adulthood. Previous research has shown that breastfed babies are less likely to develop a wide range of chronic conditions later in life, including obesity, diabetes, asthma, rheumatoid arthritis, and cardiovascular disease. Breastfed babies are also known to be much less prone to gut, ear, and respiratory infections. 

Despite the enormous health benefits associated with breastfeeding, the underlying biological mechanisms have remained unclear. Researchers have now discovered, for the first time, that breastfeeding increases a specific type of immune cells - regulatory T cells - in the first three weeks of life. These immune cells were found to be nearly twice as abundant in breastfed babies compared to babies who were fed formula.

Furthermore, the study revealed that breastfed babies have more abundant beneficial gut bacteria - Veillonella and Gemella - which specifically support the function of regulatory T cells. According to the researchers, the findings emphasize the importance of breastfeeding.

Study senior author Gergely Toldi is a researcher at the University of Birmingham and consultant neonatologist at Birmingham Women's and Children's NHS Foundation Trust.

"The influence of the type of milk received on the development of the immune response has not previously been studied in the first few weeks of life," said Toldi. "Prior to our research the outstanding importance and the early involvement of this specific cell type in breastfed babies was unknown."

"We hope this invaluable new insight will lead to an increase in rates of breastfeeding and will see more babies benefit from the advantages of receiving breastmilk."

"Furthermore, we hope for those babies who are formula fed, these results will contribute to optimising the composition of formula milk in order to exploit these immunological mechanisms. We are very grateful for the mums and babies who contributed to this special project."

Going forward, the researchers will further investigate this biological mechanism in sick and preterm newborn babies who have developed inflammatory complications.

The study is published in the journal <a href="https://onlinelibrary.wiley.com/journal/13989995">Allergy</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Study reveals why breastfed babies live healthier lives

A groundbreaking study from the University of Birmingham is providing...

Glass frogs wave their hands and feet to attract mates. Some frog species have found ways to overcome the obstacle of loud rushing water that can drown out their mating calls. Frogs that live near roaring waterfalls and streams attempt to attract mates by waving a foot, flapping a hand, or bobbing their head. 

Frogs who use visual signals have been documented near rushing streams in the rainforests of India, Borneo, and Brazil. In an exciting new study from UC Berkeley, PhD candidate Rebecca Brunner has discovered the same "dancing" behavior among glass frogs in Ecuador. 

The study marks the first time that a glass frog has been known to use visual cues for communication in response to the acoustic environment.

"A handful of other frog species around the world use visual signaling, in addition to high-pitched calls, to communicate in really loud environments," said Brunner. "What's interesting is that these species are not closely related to each other, which means that these behaviors likely evolved independently, but in response to similar environments - a concept called convergent evolution."

Sachatamia orejuela glass frogs are native to the rainforests of Ecuador and Colombia. These frogs are almost exclusively found on rocks within the spray zones of waterfalls, where they become nearly invisible to predators.

Brunner was conducting fieldwork in an Ecuadorean rainforest stream recording the call of a Sachatamia orejuela glass frog when she first observed the visual cues. She noticed the frog was repeatedly raising its front and back legs.

"I was already over the moon because I had finally found a calling male after months of searching. Before our publication, there was no official record of this species' call, and basic information like that is really important for conservation," said Brunner. "But then I saw it start doing these little waves, and I knew that I was observing something even more special."

Balancing herself on a slippery rock, Brunner caught the phenomenon on film. As she recorded, the frog continued to wave its hands and feet and bob its head. A few meters away, Brunner discovered another male Sachatamia orejuela using the same cues.

"This is a really exhilarating discovery because it's a perfect example of how an environment's soundscape can influence the species that live there," said Brunner.

"We've found that Sachatamia orejuela has an extremely high-pitched call, which helps it communicate above the lower-pitched white noise of waterfalls. And then to discover that it also waves its hands and feet to increase its chances of being noticed - that's a behavior I've always loved reading about in textbooks, so it is beyond thrilling to be able to share another amazing example with the world."

Brunner hopes to return to Ecuador soon to continue her research, which is focused on the bioacoustics of various ecosystems and conservation.

"One of the best things about fieldwork is that nature is always full of surprises - you never know what discoveries you may happen upon. I hope our findings can serve as a reminder that we share this planet with incredible biodiversity. Conserving ecosystems that support species like Sachatamia orejuela is important not only for our well-being, but also for our sense of wonder."

The study is published in the journal <a href="https://brill.com/view/journals/beh/beh-overview.xml">Behaviour</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Glass frogs wave their hands and feet to attract mates

Glass frogs wave their hands and feet to attract mates....

A new study published in <a href="https://www.nature.com/srep">Scientific Reports</a> has revealed that seagrass meadows help to remove marine plastic <a href="http://www.earth.com/news/air-pollution-contributed-to-1-67-million-deaths-in-india-last-year/">pollution</a>. The researchers estimate that Mediterranean seagrass meadows trap up to 867 million plastic items each year, most of which are carried onshore.

"Seagrass meadows are widespread in shallow coastal waters and provide important ecosystem services and benefits, such as water quality improvement, CO2 absorption, climate change mitigation, sediment production for seafloor and beach stabilization, coastal protection, nursery and refuge areas for many species, and support in fisheries production," explained the researchers.

The new investigation suggests that another benefit of underwater seagrass meadows is that they trap plastic waste and carry it to shore. 

Previous studies have found that most plastics end up in the seafloor and that some are washed back to shore. Exactly how this occurs, however, has remained unclear. 

"There is strong evidence that the seafloor constitutes a final sink for plastics from land sources," wrote the study authors. "There is also evidence that part of the plastics lying on the shallow seafloor are washed up back to the shoreline. However, little is known on the natural trapping processes leading to such landwards return."

A team led by Anna Sanchez-Vidal of the University of Barcelona set out to investigate the role that seagrass may have in trapping and removing marine plastic. The experts measured the amount of plastic debris present in seagrass litter from four beaches in Mallorca, Spain, between 2018 and 2019. Mallorca has extensive seagrass meadows, as well as high levels of plastic near the shore. 

Plastic debris was found among 50 percent of the loose seagrass leaf samples. Plastic items were also found intertwined in a substantial number of bundles of seagrass fibers known as “Neptune balls."

Up to 613 plastic items were found per kilogram of loose seagrass leaves and up to 1,470 plastic pieces were found per kilogram of Neptune balls. 

Based on this data, combined with estimates of seagrass fiber production in the Mediterranean, the experts determined that Neptune balls potentially trap 867 million pieces of plastic debris each year. 

The number of Neptune balls carried to shore, as well as the fate of the plastic after it has washed ashore, is unknown.

"There appears to be a considerable proportion of all plastic dumped into the ocean that is missing as it has not been found in surveys tracking floating plastic debris," wrote the researchers.

"Here we show that plastic debris in the shallow seafloor could be trapped in seagrass remains, eventually leaving the marine environment through beaching."

According to the study authors, the trapping services of seagrass may be particularly important in the Mediterranean Sea, where high microplastics loadings have been found at surface waters and on the seafloor. 

The researchers noted that seagrass conservation should remain a priority, as previous research found that seagrass meadows in the Mediterranean Sea have decreased by up to 50 percent since 1960.

The study is published in the journal <a href="https://www.nature.com/srep">Scientific Reports</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Seagrass meadows remove plastic debris from the ocean

A new study published in Scientific Reports has revealed that...

Stretching is more effective than walking for lowering blood pressure, according to a new study from the <a href="https://www.usask.ca/">University of Saskatchewan</a>. The research suggests that stretching should be part of a treatment plan for high blood pressure, the biggest risk factor for <a href="http://www.earth.com/news/the-cardiovascular-benefits-of-exercise-are-unlimited/">cardiovascular</a> disease. 

"Everyone thinks that stretching is just about stretching your muscles," said study co-author Dr. Phil Chilibeck. "But when you stretch your muscles, you're also stretching all the blood vessels that feed into the muscle, including all the arteries. If you reduce the stiffness in your arteries, there's less resistance to blood flow." 

Dr. Chilibeck noted that resistance to blood flow is the cause of high blood pressure, also known as hypertension. The investigation is the first of its kind to directly compare walking and stretching for reducing hypertension. 

The researchers randomly assigned 40 older adults with stage 1 hypertension to two groups for an eight-week study period. One group engaged in a full-body stretching routine for 30 minutes a day, five days a week, while the other group engaged in brisk walking for the same amount of time. 

Before and after the study period, the experts measured participants' blood pressure while they were sitting, lying down, and over 24 hours using a portable monitor. Across all three measures, stretching lowered blood pressure more than walking. 

On the other hand, participants in the walking group lost more body fat in their waist over the course of the eight weeks. According to Dr. Chilibeck, people who are walking to reduce their high blood pressure should continue to do so, but also add in some stretching sessions.

"I don't want people to come away from our research thinking they shouldn't be doing some form of aerobic activity. Things like walking, biking, or cross- country skiing all have a positive effect on body fat, cholesterol levels, and blood sugar."

Dr. Chilibeck believes the same benefits can be achieved through even shorter stretching routines that focus on the larger muscle groups in the legs, particularly the quadriceps and hamstrings. He pointed out that yoga produces similar reductions in blood pressure.

The beauty of stretching, said Dr. Chilibeck, is that it is so easy to incorporate into a daily routine. Stretching is not limited by inclement weather, is easy on the joints, and does not require a big time commitment. 

"When you're relaxing in the evening, instead of just sitting on the couch, you can get down on the floor and stretch while you're watching TV."

The study is published in the <a href="https://journals.humankinetics.com/view/journals/jpah/jpah-overview.xml">Journal of Physical Activity and Health</a>. 

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Stretching reduces high blood pressure more than walking

Stretching is more effective than walking for lowering blood pressure,...

A shocking number of lakes in the Northern Hemisphere may soon lose their ice cover for good, according to a study from <a href="https://www.yorku.ca/">York University</a>. The experts report that at the current rate of greenhouse gas emissions, about 5,700 lakes could permanently lose their ice by the end of this century, and 179 of them will become ice-free within the next decade.

The affected areas include large bays in some of the deepest of the Great Lakes, such as Lake Superior and Lake Michigan. These regions could lose their ice by 2055, unless urgent action is taken to slow global warming.

Many of the lakes that are predicted to stop freezing serve as important sources of drinking water for nearby communities. Losing ice will impact the quantity and quality of the water.

"We need ice on lakes to curtail and minimize evaporation rates in the winter," said study lead author Professor Sapna Sharma. "Without ice cover, evaporation rates would increase, and water levels could decline. We would lose freshwater, which we need for drinking and everyday activities. Ice cover is extremely important both ecologically and socio-economically."

The analysis was focused on 51,000 lakes in the Northern Hemisphere.  The researchers combined annual winter temperature projections from 2020 to 2098 with 12 climate change scenarios to determine which lakes will become ice-free.

"With increased greenhouse gas emissions, we expect greater increases in winter air temperatures, which are expected to increase much more than summer temperatures in the Northern Hemisphere," said study co-author Alessandro Filazzola. "It's this warming of a couple of degrees, as result of carbon emissions, that will cause the loss of lake ice into the future."

The lakes that have the greatest risk of losing ice cover are those in southern and coastal regions of the Northern Hemisphere, and some of them rank among the largest lakes in the world.

"It is quite dramatic for some of these lakes, that froze often, but within a few decades they stop freezing indefinitely," says Filazzola. "It's pretty shocking to imagine a lake that would normally freeze no longer doing so."

The study showed that when the air temperature was above -0.9 C, most lakes no longer froze. 

"Ice cover is also important for maintaining the quality of our freshwater," said Professor Sharma. "In years where there isn't ice cover or when the ice melts earlier, there have been observations that water temperatures are warmer in the summer, there are increased rates of primary production, plant growth, as well as an increased presence of algal blooms, some of which may be toxic."

According to Professor Sharma, more aggressive measures to mitigate greenhouse gas emissions are urgently needed to preserve lake ice cover. "I was surprised at how quickly we may see this transition to permanent loss of ice cover in lakes that had previously frozen near consistently for centuries."

The study is published in the journal <a href="https://agupubs.onlinelibrary.wiley.com/journal/19448007">Geophysical Research Letters</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Hundreds of northern lakes will permanently lose their ice cover

A shocking number of lakes in the Northern Hemisphere may...

Arguments demand a lot more <a href="http://www.earth.com/news/animals-needed-sleep-before-they-even-had-brains/">brain</a> power than agreements, according to a study from <a href="https://www.yale.edu/">Yale University</a>. While imaging neural activity, the researchers discovered that disagreements demand a lot more space in the brain. 

"Our entire brain is a social processing network," said study senior author Professor Joy Hirsch. "However, it just takes a lot more brain real estate to disagree than to agree."

The experts report that when two people agree, their brains are engaged in calm, synchronized activity that is concentrated in sensory areas of the brain. However, disagreements involve many other cognitive areas that are in charge of executive neural functions. These brain regions become mobilized as the individuals engage in a heated exchange. 

"There is a synchronicity between the brains when we agree," explained Professor Hirsch. "But when we disagree, the neural coupling disconnects."

In collaboration with experts at University College London, the researchers recruited 38 adults who were asked to either agree or disagree with a series of statements such as "Same-sex marriage is a civil right" or "Marijuana should be legalized." 

The individuals were paired together for face-to-face discussions based on their responses. Meanwhile, the researchers used an imaging technique called functional near-infrared spectroscopy to record their brain activity.

As people agreed on various topics, harmonious brain activity was observed in sensory areas of the brain such as the visual system. On the other hand, these areas of the brain were less active during disagreements. 

Heated debates were associated with increased activity in the brain's frontal lobes - the control center for higher executive functions.

According to Professor Hirsch, understanding how our brains function while disagreeing or agreeing is particularly important in a polarized political environment.

In discord, two brains engage many emotional and cognitive resources like a symphony orchestra playing different music, explained Professor Hirsch. In agreement, she said, there is less cognitive engagement and more social interaction between the brains, similar to a musical duet.

The study is published in the journal <a href="https://www.frontiersin.org/journals/human-neuroscience">Frontiers in Human Neuroscience</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Disagreements demand more space in the brain

Arguments demand a lot more brain power than agreements, according...

Oceans absorbed a record amount of heat in 2020. Ocean temperatures reached a record high in 2020, according to an international team of scientists from 13 institutes around the world. The experts report that ocean temperatures from the surface <a href="http://www.earth.com/news/groundwater-has-a-larger-impact-on-ocean-chemistry-than-expected/">water</a> all the way down to a depth of 2,000 meters reached their hottest levels since 1955.

Study lead author Lijing Cheng is a professor in the Institute of Atmospheric Physics at the <a href="https://english.cas.cn/">Chinese Academy of Sciences</a>. 

"Over 90% of the excess heat due to global warming is absorbed by the oceans, so ocean warming is a direct indicator of global warming - the warming we have measured paints a picture of long-term global warming," said Professor Cheng.

"However, due to the ocean's delayed response to global warming, the trends of ocean change will persist at least for several decades, so societies need to adapt to the now unavoidable consequences of our unabated warming. But there is still time to take action and reduce our emissions of greenhouse gases."

The investigation into ocean temperatures and salinity was focused on data from the World Ocean Database, which is overseen by the National Oceanic Atmospheric Administration. 

The analysis revealed that in 2020, the upper 2,000 meters of the world's oceans absorbed 20 more Zettajoules compared to 2019. This amount of heat is enough to boil 1.3 billion kettles.

"Why is the ocean not boiling? Because the ocean is vast. We can imagine how much energy the ocean can absorb and contain, and, when it's released slowly, how big the impact is," explained Professor Cheng.

The researchers found that other effects, including ocean salinity, were amplified in the hotter upper layer of the ocean. Marine life is threatened by both the heat and the increased salinity. 

"The fresh gets fresher; the salty gets saltier," said Professor Cheng. "The ocean takes a large amount of global warming heat, buffering global warming. However, the associated ocean changes also pose a severe risk to human and natural systems."

"Warmer oceans and a warmer atmosphere and also promote more intense rainfalls in all storms, and especially hurricanes, increasing the risk of flooding. Extreme fires like those witnessed in 2020 will become even more common in the future. Warmer oceans also make storms more powerful, particularly typhoons and hurricanes."

The researchers will continue to monitor rising ocean temperatures and the subsequent effects on salinity and stratification.

"As more countries pledge to achieve 'carbon neutrality' or 'zero carbon' in the coming decades, special attention should be paid to the ocean," said Professor Cheng. 

"Any activities or agreements to address global warming must be coupled with the understanding that the ocean has already absorbed an immense amount of heat and will continue to absorb excess energy in the Earth's system until atmospheric carbon levels are significantly lowered."

The study is published in the journal <a href="https://www.springer.com/journal/376">Advances in Atmospheric Sciences</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Oceans absorbed a record amount of heat in 2020

Oceans absorbed a record amount of heat in 2020. Ocean...

There is no limit to the cardiovascular benefits of <a href="http://www.earth.com/video/high-intensity-exercise-can-help-you-live-longer/">exercise</a>, according to a new study published by <a href="https://plos.org/">PLOS</a>. The researchers found that people who are the most active have the lowest risk of cardiovascular disease.

While the link between exercise and reduced cardiovascular risk was previously established, the extent of these benefits remained unclear. 

A team led by Terence Dwyer of University of Oxford set out to investigate by analyzing data from 90,211 UK Biobank participants who did not have cardiovascular disease. The individuals had worn activity trackers over a 7-day period from 2013 through 2015.

During five years of follow-up, 3,617 of the participants were diagnosed with cardiovascular disease. The more physically active the individuals were, the less likely they were to develop cardiovascular issues. For example, those who exercised the least were about 54 percent more likely to be diagnosed with cardiovascular disease compared to the most active people. 

Participants in the lowest category of physical activity, who also smoked more and had higher body mass index, were most often diagnosed with hypertension. 

"This is the largest ever study of exquisite device-measured physical activity and cardiovascular disease. It shows that physical activity is probably even more important for the prevention of cardiovascular disease than we previously thought," said Professor Aiden Doherty. 

"Our findings lend further weight to the new WHO guidelines on physical activity which recommend at least 150 to 300 minutes of moderate to vigorous aerobic activity per week for all adults."

According to Professor Dwyer, the results of the study reaffirms that physical activity is an important way of preventing cardiovascular disease. 

"The potential risk reduction estimated in those engaging in relatively high levels of activity is substantial and justifies a greater emphasis on measures to increase levels of physical activity in the community."

The study is published in the journal <a href="https://journals.plos.org/plosmedicine/">PLOS Medicine</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The cardiovascular benefits of exercise are unlimited

There is no limit to the cardiovascular benefits of exercise,...

<a href="http://www.earth.com/news/groundwater-has-a-larger-impact-on-ocean-chemistry-than-expected/">Ocean</a> temperatures are becoming increasingly unsuitable for baby sharks, according to a new study from the <a href="https://www.coralcoe.org.au/">ARC Center of Excellence for Coral Reef Studies</a>. The researchers found that as a result of global warming, baby sharks are born smaller, exhausted, and undernourished. The animals are also being birthed into environments that are already difficult for them to survive in.

The study was focused on epaulette sharks, an egg-laying species found only on the Great Barrier Reef. The team examined the impacts of warmer temperatures on the growth, development, and physiological performance of the sharks as embryos and as hatchlings.

"We tested shark embryos in waters up to 31°C," said study lead author Carolyn Wheeler. "The hotter the conditions, the faster everything happened, which could be a problem for the sharks." 

"The embryos grew faster and used their yolk sac quicker, which is their only source of food as they develop in the egg case. This led to them hatching earlier than usual." 

The hatchlings were not only smaller, but were undernourished, lacked energy, and needed to feed almost right away.

Study co-author Dr. Jodie Rummer noted that the waters of the Great Barrier Reef will likely experience summer averages close to or even in excess of 31°C by the end of the century.

Dr. Rummer warned that rising ocean temperatures are a major concern for the future of all sharks, whether they lay eggs or give birth.

"The epaulette shark is known for its resilience to change, even to ocean acidification. So, if this species can't cope with warming waters then how will other, less tolerant species fare?" 

"Our future ecosystems depend us taking urgent action to limit climate change."

Sharks belong to a group of animals that develop and grow slowly, like rays and skates, and they do not reproduce as often as other fish.

The findings suggest that the sharks of the future will be born at a major disadvantage healthwise. To make matters worse, their environments will already be the warmest temperatures that the sharks can tolerate.

"The study presents a worrying future given that sharks are already threatened," said Wheeler. "Sharks are important predators that keep ocean ecosystems healthy. Without predators, whole ecosystems can collapse, which is why we need to keep studying and protecting these creatures."

The study is published in the journal <a href="https://www.nature.com/srep/?gclid=Cj0KCQiArvX_BRCyARIsAKsnTxM7BZ8nYNx5N0Pi-LOdKZiJCT5EHNkwJZzUmIRfI5MxnPaCv7UY3sgaArNsEALw_wcB">Scientific Reports</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Oceans are already too warm for baby sharks

Ocean temperatures are becoming increasingly unsuitable for baby sharks, according...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=3Y4eLFNYrKE
</div></figure>



On the unforgiving landscape of North Greenland, temperatures drop and sunlight barely penetrates through the polar winter. It was here, however, that an international team of scientists found <a href="https://www.earth.com/news/predatory-worms-were-terror-beasts-half-a-billion-years-ago/#google_vignette" target="_blank" rel="noreferrer noopener">evidence of sea monsters</a> that would change our understanding of ocean life in the past.



This video captures the discovery of Timorebestia fossils that had been hidden for more than 500 million years in the Sirius Passet formation. The "terror beasts," as they are called, are a hidden chapter in the evolutionary history of <a href="https://www.earth.com" target="_blank" rel="noreferrer noopener">Earth</a>, showing that sophisticated predator-prey interactions occurred much earlier than previously envisioned.



Dr. Jakob Vinther and his research team at the <a href="https://www.bristol.ac.uk/" target="_blank" rel="noreferrer noopener">University of Bristol</a>, in collaboration with researchers at the <a href="https://eng.kopri.re.kr/" target="_blank" rel="noreferrer noopener">Korean Polar Research Institute</a>, braved extreme weather conditions at 82.5 north latitude to locate these giant creatures. Using sophisticated electron microprobe analysis, they revealed the detailed anatomy of the animals, including their muscle and nerve tissues.



The find upsets the traditional timeline of sea predators. Although we've long appreciated that Cambrian oceans were at one time ruled by <a href="https://www.youtube.com/watch?v=jWI3-UgA3_o&amp;list=PL1QLQMW9MWDwpkFOnvgAmu7wT6rZmYqdJ&amp;index=19" target="_blank" rel="noreferrer noopener">arthropods</a>, these discoveries indicate that relatives of arrow worms were first to dominate the seas. These worms were building sophisticated food webs several million years before other predator groups arose.



Each fossil is a story of ancient hunger, with fossil stomach contents revealing these meter-long beasts dined on heavily armored arthropods regularly, cementing their place as the ocean's first apex predators.



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Worms dominated seas before dinosaurs

https://www.youtube.com/watch?v=3Y4eLFNYrKE On the unforgiving landscape of North Greenland, temperatures drop...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=Ow3JH03PqEQ
</div><figcaption class="wp-element-caption">New York is the site of the world's oldest forest.</figcaption></figure>



<h2 class="wp-block-heading" id="h-385-million-year-old-trees-discovered">385-million-year-old trees discovered</h2>



Scientists have uncovered something extraordinary just two hours north of New York City. The <a href="https://www.earth.com/news/worlds-oldest-forest-discovered-close-to-new-york-city/" target="_blank" rel="noreferrer noopener">world's oldest forest</a>, dating back 385 million years, offers a window into how Earth's first complex forests shaped our planet's atmosphere.



Located near <a href="https://townofcairo.com/" target="_blank" rel="noreferrer noopener">Cairo, New York</a>, in Greene County, these weren't merely primitive plants struggling to survive. These were sophisticated trees with root systems remarkably similar to modern forests. This ancient woodland predates dinosaurs by 140 million years.



<h2 class="wp-block-heading" id="h-the-cairo-forest-discovery">The Cairo forest discovery</h2>



385 million years ago, upstate New York was a tropical paradise near the equator. Thanks to continental drift, this ancient forest has traveled thousands of miles to its current location.



The fossil forest sits in an abandoned quarry, roughly half the size of a football field. This represents just a slice of what was likely a massive forest system stretching from New York into Pennsylvania.



Charles Ver Straeten, curator of sedimentary rocks at the <a href="https://www.nysm.nysed.gov/" target="_blank" rel="noreferrer noopener">New York State Museum</a>, made the discovery in 2009. While scouting the former highway department property, his trained eye spotted wandering patterns in the stone that looked like marine features.



<h2 class="wp-block-heading" id="h-revolutionary-age-and-preservation">Revolutionary age and preservation</h2>



The site contains 385-million-year-old rocks with fossilized woody roots forming horizontal patterns up to 18 feet (5.5 meters) wide. As Christopher Berry, a paleobotanist at Cardiff University, explains: "You are walking through the roots of ancient trees."



This discovery pushes back advanced tree evolution by millions of years. The research, published in <a href="https://www.cell.com/current-biology/home" target="_blank" rel="noreferrer noopener">Current Biology</a> in December 2019, fundamentally changes our understanding of when complex forests first emerged.



Researchers believe a massive flood buried the forest floor, creating perfect fossilization conditions. Over millions of years, sediment hardened into rock, preserving these root patterns like nature's time capsule.



<h2 class="wp-block-heading" id="h-meet-archaeopteris-the-first-modern-tree">Meet Archaeopteris: the first modern tree</h2>



The star of this ancient forest is Archaeopteris – not to be confused with the feathered dinosaur Archaeopteryx. This tree was far older and more revolutionary.



William Stein from <a href="https://www.binghamton.edu/" target="_blank" rel="noreferrer noopener">Binghamton University</a> describes the roots as "strikingly modern, essentially what you'd see outside in my yard right now." These weren't simple root systems you'd expect from ancient plants.



Some fossilized roots are six inches (15 centimeters) in diameter, forming 36-foot-wide (11-meter) patterns. These giants grew up to 65 feet (20 meters) tall with five-foot-diameter (1.5-meter) trunks.



<h2 class="wp-block-heading" id="h-climate-changing-impact">Climate-changing impact</h2>



These trees fundamentally changed Earth's environment. Kevin Boyce, a Stanford University geoscientist, explains how their deep roots triggered "weathering," chemical reactions that pulled carbon dioxide from the atmosphere.



This process dropped atmospheric CO2 levels from 10-15 times higher than today to roughly modern concentrations. These ancient trees helped create atmospheric conditions that made complex life possible.



<h2 class="wp-block-heading" id="h-ancient-forest-ecosystem">Ancient forest ecosystem</h2>



The forest was remarkably diverse. Scientists identified Eospermatopteris, palm tree-like plants with short roots that reached 30 feet (9 meters) tall but lacked woody structure. The forest also housed cladoxylopsids and a mysterious third species still being studied.



All reproduced through spores rather than seeds – millions of years before seeds evolved. This tropical environment had no grass, flowers, or flying insects, just towering trees creating Earth's first complex forest canopy.



<h2 class="wp-block-heading" id="h-scientific-significance">Scientific significance</h2>



Before this finding, the Gilboa forest, located 25 miles (40 kilometers) away, held the "oldest forest" title. Cairo's trees are 2-3 million years older, showing that complex forest ecosystems developed much faster than scientists believed possible.



Patricia Gensel, a <a href="https://www.unc.edu/" target="_blank" rel="noreferrer noopener">University of North Carolina</a> paleobotanist, notes: "The size of those root systems is really changing the picture. Even 20 years ago, researchers assumed trees with such complex root systems didn't evolve so early."



The Cairo site presents three unique root systems, suggesting Devonian period forests were diverse ecosystems with different trees occupying different environmental niches, much like today's forests.



<h2 class="wp-block-heading" id="h-modern-preservation-efforts">Modern preservation efforts</h2>



In 2022, New York State Senator Michelle Hinchey secured a $170,000 grant for the town of Cairo to construct specialized fencing around the fossil forest site. The town plans to conduct a feasibility study exploring the possibility of creating an educational center and working lab on-site.



Joe Hasenkopf, chair of the Cairo Planning Board, hopes to partner with educational institutions to create a research facility serving scientists, students, and the public.



<h2 class="wp-block-heading" id="h-lessons-for-today-s-climate">Lessons for today's climate</h2>



Why does a 385-million-year-old forest matter today? It shows how dramatically forests can change Earth's climate. These ancient woodlands created the atmospheric conditions supporting complex life.



Understanding how prehistoric forests transformed the planet helps us appreciate modern forests' critical role in addressing climate change. Forests remain Earth's most effective carbon capture systems.



These prehistoric trees changed Earth's atmosphere by pulling massive amounts of carbon dioxide from the air. As we face modern climate challenges, this ancient forest reminds us of trees' incredible power to transform our planet's environment.



The next time you walk through a forest, remember you're experiencing an ecosystem whose blueprint was established 385 million years ago in upstate New York. These ancient pioneers didn't just survive – they thrived and changed the world forever.



The full study was published in the journal Current Biology.



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Earth's oldest forest found in the United States

https://www.youtube.com/watch?v=Ow3JH03PqEQ New York is the site of the world's oldest...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=prrq8Ql81zk
</div><figcaption class="wp-element-caption">Acid rain and a crisis solved.</figcaption></figure>



<h2 class="wp-block-heading" id="h-why-don-t-we-ever-hear-about-acid-rain-anymore-the-environmental-crisis-that-was-solved">Why don't we ever hear about "acid rain" anymore? The environmental crisis that was solved</h2>



Remember the 1980s when acid rain dominated headlines? Dire warnings about rain eating buildings, killing fish, and destroying forests filled every news cycle. Then, almost like magic, acid rain vanished from public discourse. What happened? Did we actually solve one of the late 20th century's most pressing environmental challenges?



The answer might surprise you. Unlike many environmental issues that drag on indefinitely, acid rain represents one of modern history's most successful ecological recovery stories. It's a tale of science, politics, and technology working together to tackle what seemed impossible.



<h2 class="wp-block-heading">What was acid rain?</h2>



Acid rain isn't regular rain having a bad day – it's precipitation that became significantly more acidic due to air pollution. When power plants, factories, and vehicles burn fossil fuels, they release sulfur dioxide (SO2) and nitrogen oxides (NOx) into the atmosphere.



<h2 class="wp-block-heading">The science behind it</h2>



Think of acid rain as nature's chemistry experiment gone wrong. These compounds react with water, oxygen, and other chemicals to form sulfuric and nitric acids. When mixed with water vapor in clouds, they create precipitation with dangerously low pH levels.



While clean rain has a pH of about 5.6, acid rain could drop as low as 4.2 to 4.4 – roughly as acidic as tomato juice or coffee. According to US Geological Survey documentation, Scottish chemist Angus Smith first coined "acid rain" in 1872, but it didn't become a household phrase until the 1960s and 1970s when Swedish scientist Svante Odén documented its devastating effects on Scandinavian lakes and European forests.



<h2 class="wp-block-heading">The crisis at its peak</h2>



During the height of public concern, environmental damage was both widespread and visible. This wasn't some abstract future threat – people could see destruction happening in real-time.



<h2 class="wp-block-heading">Environmental devastation</h2>



The most dramatic impacts were impossible to ignore. Research documented by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation shows that in the Adirondack Mountains, more than 200 lakes became so acidic they couldn't support fish life. The Adirondack Council reports that 409 lakes once supported brook trout, but many lost their fish populations due to acid rain.



By 1976, when scientists cataloged all acidified lakes in the Adirondack Park, researchers found that half of the lakes over 2,000 feet above sea level had no fish, according to studies published in environmental journals. The acidification process worked like a slow-motion disaster. As acid rain fell into watersheds, it gradually lowered pH levels. Fish couldn't survive in acidic water, and their food sources died off too.



Trees at high elevations showed stress directly linked to acid rain. It weakened them by leaching nutrients and making them susceptible to disease. Historical records show Germany's Black Forest saw nearly half its trees damaged by the mid-1980s.



<h2 class="wp-block-heading">Economic impact</h2>



Acid rain wasn't just environmental – it was expensive. Acidic precipitation corroded infrastructure, buildings, and monuments. Historic stone structures deteriorated at accelerated rates. Tourism suffered as lakes became fishless and forests declined. EPA economic analyses from the period documented repair costs mounting into billions annually.



<h2 class="wp-block-heading">The solution: government action and technology</h2>



Transformation from crisis to success required unprecedented cooperation between governments, industries, and environmental groups.



<h2 class="wp-block-heading">The Clean Air Act of 1990</h2>



The turning point came with the Clean Air Act Amendments of 1990, signed by President George H.W. Bush. This represented a fundamentally new approach to environmental regulation, as documented in EPA historical records.



<h2 class="wp-block-heading">Cap-and-trade success</h2>



Instead of mandating specific technologies, the 1990 amendments introduced something revolutionary: a cap-and-trade system for sulfur dioxide emissions. EPA program documentation shows this market-based approach set overall limits but allowed companies to trade emission allowances.



The genius was harnessing market forces to find cost-effective pollution reduction. Companies reducing emissions cheaply could sell excess allowances to those facing higher costs. Research published in environmental economics journals and EPA progress reports shows this resulted in dramatic SO2 reduction at a fraction of projected costs.



<h2 class="wp-block-heading">Technology advances</h2>



Policy provided the framework, but technology made reductions possible. Studies in atmospheric science journals document the widespread adoption of flue gas desulfurization systems ("scrubbers") that removed sulfur dioxide before it reached the atmosphere. By the 2000s, new installations could remove over 95% of SO2 emissions, according to EPA technical reports.



The push coincided with cleaner energy development. Natural gas produces fewer sulfur compounds than coal. Wind and solar, emerging in the 1990s, captured growing market share, reducing reliance on high-sulfur coal.



<h2 class="wp-block-heading" id="h-why-we-don-t-hear-about-it-today">Why we don't hear about it today</h2>



Why did acid rain disappear from headlines? Simple: the problem was largely solved.



<h2 class="wp-block-heading">Success doesn't make news</h2>



There's an old journalism saying: "If it bleeds, it leads." Environmental success stories don't generate urgency like crisis reporting. Media attention shifted to other challenges: climate change, plastic pollution, and biodiversity loss. There's only so much environmental anxiety the public can absorb, and newer concerns replaced acid rain.



<h2 class="wp-block-heading">Mission accomplished</h2>



The primary reason is beautifully simple: interventions worked. EPA monitoring data shows sulfur dioxide emissions dropped over 90% since 1990. Academic research published in environmental science journals confirms pH levels in formerly affected areas returned closer to normal. This represents one of history's most dramatic environmental recoveries. Studies by the Adirondack Lakes Survey Corporation show fishless lakes now support healthy populations. Forests recovered, and building damage slowed dramatically.



<h2 class="wp-block-heading" id="h-is-it-really-gone">Is it really gone?</h2>



The crisis is largely resolved, but monitoring data shows the problem isn't completely eliminated – it's managed to acceptable levels. Some areas still experience occasional events during high pollution periods. International environmental research indicates that rapidly industrializing Asian countries face similar problems to what we experienced decades ago, though they're implementing successful strategies.



EPA research shows nitrogen oxide emissions proved more challenging than sulfur dioxide, coming from vehicles and mobile sources. Climate science studies suggest changing weather patterns add complexity to how acid rain forms and falls.



<h2 class="wp-block-heading">What this teaches us</h2>



The acid rain experience proves that seemingly intractable environmental problems can be solved with scientific understanding, political will, and technological innovation. Environmental monitoring data shows recovery speed was remarkable – within a decade, measurable improvements appeared in air quality and ecosystem health.



Success came from bipartisan support across party lines. Policy analysis studies show the market-based approach appealed to those preferring economic incentives while achieving environmental goals. This support created lasting policy surviving political changes.



<h2 class="wp-block-heading">Conclusion</h2>



Acid rain's disappearance from public consciousness represents environmental science's greatest success stories. Through effective regulation, technological innovation, and international cooperation, we transformed an overwhelming crisis into a manageable challenge.



Today's silence isn't because we forgot – it's because we solved it. The 1990 Clean Air Act, combined with technology and energy market changes, reduced acid rain emissions over 90%, according to comprehensive EPA data analysis.



This success offers hope for current challenges. It proves complex problems can be solved when science, policy, and technology work together. As we face climate change and plastic pollution, acid rain reminds us that dramatic positive change is possible.



Next time someone asks whether environmental regulations work, remember acid rain. It's proof that sometimes, we get it right.



<hr class="wp-block-separator has-alpha-channel-opacity"/>



Sources: This article draws from EPA official documentation and progress reports, peer-reviewed research published in environmental and atmospheric science journals, historical data from the Adirondack Lakes Survey Corporation, New York State Department of Environmental Conservation records, US Geological Survey publications, policy analysis studies, and environmental monitoring data collected over three decades.



<h2 class="wp-block-heading">Frequently Asked Questions</h2>



1. Is acid rain completely gone? No, but EPA monitoring shows it's reduced to manageable levels. US sulfur dioxide emissions dropped over 90% since 1990, making acid rain much less severe than the 1980s crisis.



2. How long did solving take? Environmental monitoring data shows significant improvements began within 5-10 years of 1990s emission controls. Full ecosystem recovery took longer – some areas need 20-30 years for complete recovery.



3. What made the solution successful? Clear scientific understanding, visible damage motivating action, bipartisan support, available technology, and innovative market-based policies like cap-and-trade.



4. Do other countries have acid rain problems? Yes, particularly rapidly industrializing Asian countries. However, international environmental research shows many implement similar successful control strategies.



5. Could acid rain return? Potentially, if regulations weaken or we return to high-sulfur coal without controls, though effects would take years to become severe according to environmental projections.



6. Can you recommend any teaching tools on the subject of "acid rain"? The United States Environmental Protection Agency produced a wonderful teacher's guide for ages 14 and under that you can find on the EPA website here: <a href="https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf" target="_blank" rel="noreferrer noopener">https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf</a>



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The environmental problem we actually solved

https://www.youtube.com/watch?v=prrq8Ql81zk Acid rain and a crisis solved. Why don't we...

Fresh,Radish,Harvest,On,Soil,In,Garden.

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Mid-July is an opportune time to kick-start a thriving fall garden, and this guide lays out the best vegetables and herbs to plant now for a fruitful autumn harvest. 



Fast-growing leafy greens such as spinach, lettuce, kale, and arugula perform especially well in the waning summer heat, with harvests beginning as soon as 30 days. 



These cool-season crops relish the transition into fall, offering repeated yields with cut-and-come-again methods.



Root vegetables like radishes, carrots, and beets also excel during this period. Radishes deliver satisfaction in under a month, while carrots and beets mature in about two months. Employing succession planting ensures a continuous stream of produce deep into the cooler months. 



For a boost of fresh flavor, herbs like cilantro, basil, dill, and chervil are excellent picks. These heat-loving varieties flourish in July’s warmth and are harvest-ready in about 30 days, especially when sown continuously.



Gardeners in zones 6 through 9 can benefit from planting bush beans and snap peas, which don’t require trellising and are ideal for compact plots. 



Maturing in 50–60 days, they’re a smart choice for quick, protein-rich harvests. For those in hotter regions, heat-tolerant crops such as okra and southern peas provide reliable yields and thrive in scorching conditions.



This guide emphasizes more than crop selection—it highlights the importance of timing, soil preparation, and ongoing sowing techniques. 



With thoughtful planning and attention to regional climate needs, even late-summer gardeners can enjoy fresh salads, hearty stews, and the satisfaction of a robust, homegrown harvest well into fall.



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What to plant in your garden in mid-July

https://youtu.be/Fi2OeEwuzRM?si=vTyd2m9FMmtyWkex Mid-July is an opportune time to kick-start a thriving...

Green,Ecoduct,Over,An,Empty,Highway,During,Sunset.

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A new long-term study in Monkton, Vermont, reveals that wildlife tunnels significantly reduce amphibian road mortality during seasonal migrations. 



Frogs and salamanders often cross roads to reach breeding ponds each spring, but many are killed by vehicles. 



Researchers from the <a href="https://www.uvm.edu/" target="_blank" rel="noreferrer noopener">University of Vermont</a>, in collaboration with local citizens and the Vermont Agency of Natural Resources, installed two underpass tunnels in 2015. 



Over a 12-year monitoring period, they observed an 80.2% reduction in amphibian deaths, and up to 94% for non-climbing species like salamanders. 



The study used a before-after-control-impact design and documented more than 5,200 amphibians, highlighting the tunnels’ effectiveness even in nearby buffer zones.



Funded at $342,397 - far cheaper than wildlife crossings for large mammals - the project showcased the power of community-led conservation.



Local groups initiated the effort after observing mass amphibian deaths. Wildlife cameras later captured over 2,200 amphibians using a tunnel in just one spring, along with other species like raccoons and bobcats, indicating wider ecosystem benefits.



This marks the first peer-reviewed, long-term data set in the northeastern U.S. confirming amphibian-specific underpasses work. 



The study urges transportation departments to incorporate these designs into road planning and highlights how community action, thoughtful infrastructure, and persistence can make a real difference for biodiversity.



The full study was published in the <a href="https://linkinghub.elsevier.com/retrieve/pii/S1617138125000780" target="_blank" rel="noreferrer noopener">Journal for Nature Conservation</a>.



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Wildlife tunnels save millions of amphibians

https://youtu.be/XYgiPzmNBTU?si=eFYY7gPHU1JznLvU A new long-term study in Monkton, Vermont, reveals that...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



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Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nushagak Bay in southwest Alaska

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lake Trasimeno in Central Italy

[sendtonews key="3upvlAaHgO-2256633-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> explores the ability of salt to transform the way that foods and beverages taste. Salt is known to cover up undesirable flavors, such as bitterness in coffee or beer, but how exactly does sodium chloride change the taste of other compounds?



One previous study showed that, not only does salt suppress bitterness, but also enhances sweetness and sourness. Another study revealed that bitterness reduction by salt seems to be happening at the tongue receptor level as well as in the brain.&nbsp;



While it is known that salt taste is mediated by the presence of sodium channels in the form of taste buds, experts believe that there is also an unknown receptor responsible for how we taste salt that has not yet been identified.&nbsp;



Video Credit: ACS Reactions



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

How does salt makes things taste better?

[sendtonews key="X0f6OHYoI4-2310561-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



'The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September)."



"The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries," says ESA.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Santiago, Chile in South America

[sendtonews key="JRaP49ISmm-2357509-12187" type="single"] Today’s Video of the Day from the...

Spiral,Galaxy,,Illustration,Of,Milky,Way

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Astronomers at <a href="https://www.jhu.edu/">Johns Hopkins University</a> have created an interactive map of the universe, including the actual position and real colors of 200,000 galaxies. The map allows the public to access data that was previously only available to scientists.



The map was developed using data collected by the Sloan Digital Sky Survey. For over two decades, a telescope in New Mexico was aimed at slightly different locations to capture the night sky.&nbsp;



"Growing up I was very inspired by astronomy pictures, stars, nebulae and galaxies, and now it's our time to create a new type of picture to inspire people," said map creator Brice Ménard, a professor at Johns Hopkins. "Astrophysicists around the world have been analyzing this data for years, leading to thousands of scientific papers and discoveries. But nobody took the time to create a map that is beautiful, scientifically accurate, and accessible to people who are not scientists. Our goal here is to show everybody what the universe really looks like."



"In this map, we are just a speck at the very bottom, just one pixel. And when I say we, I mean our galaxy, the Milky Way which has billions of stars and planets. We are used to seeing astronomical pictures showing one galaxy here, one galaxy there or perhaps a group of galaxies. But what this map shows is a very, very different scale."



"From this speck at the bottom, we are able to map out galaxies across the entire universe, and that says something about the power of science."



The <a href="https://mapoftheuniverse.net/">interactive map</a> is available online, where it can be downloaded for free.



Video Credit: Johns Hopkins&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Interactive map of the universe includes 200,000 galaxies

[sendtonews key="e4ZG0Jawp3-2374785-12187" type="single"] Astronomers at Johns Hopkins University have created...

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Lesotho: Africa's "Kingdom in the Sky" Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features northwest Lesotho in South Africa.



According to ESA, Lesotho is the only nation in the world that lies completely above 1,000 m in elevation. The country is famous for its tall mountains and narrow valleys, and is known as Africa's "Kingdom in the Sky."



Out of a population of around two million people, about 80 percent live in rural areas. More than 75 percent of these people are engaged in <a href="https://www.earth.com/news/climate-change-will-have-a-global-impact-on-agriculture/">agriculture</a>, including rainfed cereal production and animal grazing.&nbsp;



ESA reports that the country’s agricultural system faces a growing number of issues, with climate-related vulnerabilities such as drought, floods and extreme temperatures occurring more frequently. 



Diamonds are amongst the minerals found in the mountains. Indeed, Lesotho can truly be called the Kingdom in the Sky. Beautiful, culturally rich, safe, affordable, and easily accessible from Durban and Johannesburg, mountainous Lesotho is a vastly underrated travel destination. the Kingdom of Lesotho (Sotho: 'Muso oa Lesotho) is an enclaved country in southern Africa. It is just over 30,000 km2 (11,583 sq mi) in size and has a population of around 2 million.



Video Credit: ESA&nbsp;&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer 



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Lesotho: Africa's "Kingdom in the Sky"

[sendtonews key="uV9Lh2fQbV-1760058-12187" type="single"] Lesotho: Africa's "Kingdom in the Sky" Today’s...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The city of Dublin on Ireland's east coast

[sendtonews key="qjvhBOBnY8-2426650-12187" type="single"] Today's Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The province of Zaragoza in northeast Spain

[sendtonews key="oL4FnPTGCV-2384527-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The rapid retreat of the Columbia Glacier

[sendtonews key="0879czfG3k-1785905-12187" type="single"] Today’s Video of the Day from NASA...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The Pyrenees Mountains in southwest Europe

[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"] Today’s Video of the Day from the...

Earth,Like,Exoplanet,3d,Render

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Two distant planets may be "water worlds"

[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"] Today's Video of the Day from NASA...

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Satellites reveal how Earth's systems are interconnected Today’s Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes Earth’s interconnected systems, and how this network is affected by rising temperatures.&nbsp;



During 2020, average global temperatures matched the hottest year on record. The hurricane season was also record-breaking, with many of the storms intensifying at extraordinary speeds. Hot water in the ocean is fuel for hurricanes. The satellite data shows that it's all one interconnected system showing how Satellites reveal how Earth's systems are interconnected.



According to NASA, dust swept up from Northern Africa plays a major role in the formation of hurricanes, and is also a key source of fertilization in the Amazon rainforest. As a result of<a href="https://www.earth.com/news/seagrass-wasting-disease-is-fueled-by-climate-change/"> climate</a> change, dust plumes are expected to decline, which will have an effect on vegetation far away.&nbsp;



Images from Earth-observing satellites show how the world’s plant life is affected by natural disasters, fires, and deforestation. Satellites also reveal how widespread changes in vegetation impact waterways,&nbsp; the climate, air quality. Satellites communicate by using radio waves to send signals to the antennas on the Earth. "Earth From Space" is a groundbreaking two-hour special that reveals a spectacular new space-based vision of our planet. 



Video Credit: NASA Goddard&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Satellites reveal how Earth's systems are interconnected

[sendtonews key="JbW4VsY53O-1632195-12187" type="single"] Satellites reveal how Earth's systems are interconnected...

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