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...

The largest human <a href="https://www.earth.com/news/birds-got-their-diverse-skulls-in-the-time-of-dinosaurs/">skull</a>, the so-called Harbin cranium, sits in collections at a museum in Hebei GEO University in China. Researchers now think that the skull could belong to our nearest relative, "Dragon Man," replacing Neanderthals in this important position. 

Three papers published by <a href="https://www.cell.com/">Cell Press</a> in the June 25th issue of the journal Innovation support this position. 

“The Harbin fossil is one of the most complete human cranial fossils in the world," said study co-author Professor Qiang Ji. "This fossil preserved many morphological details that are critical for understanding the evolution of the Homo genus and the origin of Homo sapiens."

The fossil is now described as a new species, Homo longi or Dragon Man. The skull was first discovered in the 1930s in China and holds a brain larger than the modern human brain, large squarish eye sockets and large brow ridges. The mouth is wide with large teeth. 

The skull is believed to have belonged to a 50-year-old male that lived in a forested floodplain as part of a small hunter-gatherer community. The individual was almost certainly quite large by modern human standards.  

Using chemical analysis, the researchers dated the skull to 146,000 years old, a time when many Homo sapiens populations were on the move and it’s possible that H. longi may have encountered H. sapiens in the area. It’s an open question whether like Neanderthals, if there may have been hybridization between the two species. 

The paleontologists created a new tree of life for humans, including Dragon Man as our sister group and Neanderthals as a more distant relative that diverged from our lineage further back in time. Only time will tell if further discoveries will complicate or validate this new view of human evolution.     

"It is widely believed that the Neanderthal belongs to an extinct lineage that is the closest relative of our own species. However, our discovery suggests that the new lineage we identified that includes Homo longi is the actual sister group of H. sapiens," explained study co-author Professor Xijun Ni. 

The new human tree of life also suggests that our common ancestor with Neanderthals existed even further back in time.

"The divergence time between H. sapiens and the Neanderthals may be even deeper in evolutionary history than generally believed, over one million years," said Professor Ni.

"Altogether, the Harbin cranium provides more evidence for us to understand Homo diversity and evolutionary relationships among these diverse Homo species and populations. We found our long-lost sister lineage."

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

"Dragon Man" may be our new closest relative

The largest human skull, the so-called Harbin cranium, sits in...

Some <a href="https://www.earth.com/video/neanderthals-may-have-communicated-like-modern-humans/">Neanderthals</a> may have actually originated in the Levant region of Western Asia and not in Europe, according to a new study from <a href="https://english.tau.ac.il/">Tel Aviv University</a>. The experts have discovered a previously unknown group of humans, with distinct features and characteristics, that resemble Pre-Neanderthal populations in Europe. 

The new finding suggests that two types of Homo groups lived side by side in the Levant region of Western Asia for more than 100,000 years, sharing knowledge and tool technologies. The research indicates that the Nesher Ramla people, who lived in the region from around 400,000 years ago, were joined by Homo sapiens about 200,000 years later.

According to the researchers, at least some of the later Homo fossils found previously in Israel do not belong to early Homo sapiens, but to groups of mixed Homo sapiens and Nesher Ramla lineage - the Nesher Ramla Homo type.

"The discovery of a new type of Homo is of great scientific importance. It enables us to make new sense of previously found human fossils, add another piece to the puzzle of human evolution, and understand the migrations of humans in the old world," said study co-author Professor Israel Hershkovitz.

"Even though they lived so long ago, in the late middle Pleistocene (474,000-130,000 years ago), the Nesher Ramla people can tell us a fascinating tale, revealing a great deal about their descendants' evolution and way of life."

The relevant human fossil was found by Dr. Yossi Zaidner from the Institute of Archaeology at the Hebrew University of Jerusalem during salvage excavations at the Nesher Ramla prehistoric site.

"This is an extraordinary discovery. We had never imagined that alongside Homo sapiens, archaic Homo roamed the area so late in human history. The archaeological finds associated with human fossils show that 'Nesher Ramla Homo' possessed advanced stone-tool production technologies and most likely interacted with the local Homo sapiens," explained Dr. Zaidner.

Professor Hershkovitz noted that the discovery of the Nesher Ramla Homo type challenges the prevailing hypothesis that the Neanderthals originated in Europe. 

"Before these new findings, most researchers believed the Neanderthals to be a 'European story', in which small groups of Neanderthals were forced to migrate southwards to escape the spreading glaciers, with some arriving in the Land of Israel about 70,000 years ago," said Professor Hershkovitz.

"The Nesher Ramla fossils make us question this theory, suggesting that the ancestors of European Neanderthals lived in the Levant as early as 400,000 years ago, repeatedly migrating westward to Europe and eastward to Asia. In fact, our findings imply that the famous Neanderthals of Western Europe are only the remnants of a much larger population that lived here in the Levant - and not the other way around."

According to Dr. Hila May of the Sackler Faculty of Medicine, the discovery may help to solve the mystery of how genes from Homo sapiens penetrated the Neanderthal population that had presumably lived in Europe long before the arrival of Homo sapiens.

"Europe was not the exclusive refugium of Neanderthals from where they occasionally diffused into West Asia," said Professor Gerhard Weber of Vienna University. "We think that there was much more lateral exchange in Eurasia, and that the Levant is geographically a crucial starting point, or at a least bridgehead, for this process."

The study is published in the journal <a href="https://www.sciencemag.org/">Science</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

New type of prehistoric human found in the Levant

Some Neanderthals may have actually originated in the Levant region...

There is a general rule for <a href="https://www.earth.com/news/some-mammals-actually-benefit-from-human-disturbance/">mammal</a> vocalizations - the larger the animal’s vocal fold, the lower the vocalization’s fundamental frequency. Large vocal folds such as those found in Asian elephants set an upper limit to the fundamental frequency of sounds produced by them.

In keeping with this rule, many of the sounds Asian elephants produce are low frequency calls - trumpets and infrasonic rumbles below the threshold of human hearing. Researchers at the <a href="https://www.univie.ac.at/en/">University of Vienna</a> have been studying these vocalizations for decades.

Asian elephants - but not their African cousins - make a high pitched squeaking noise that cannot, if the rule holds, be produced by their large vocal folds. To investigate, the experts analyzed the squeak sounds in Asian elephants from Nepal. 

The research team used 48 microphones and a special camera that translates the location of sounds into colors, similar to a heat sensing camera. In this way, the precise location of each sound was visually mapped as it was created. 

The researchers discovered that the squeaking sound is created by the elephant’s mouth, not by the trunk as in trumpeting. 

"Our results strongly suggest that Asian elephants force air from the small oral cavity through the tensed lips, inducing self-sustained lip vibration. Besides human brass players, lip buzzing is not described elsewhere in the animal kingdom," wrote the study authors.

"Given the complexity of the proposed mechanism, the surprising absence of squeaking in most of the unrelated subjects and the indication for volitional control, we hypothesize that squeak production involves social learning."

The research supports other recent discoveries which show that elephants have the ability to learn and repeat novel sounds they hear. The study highlights the elephant’s vocal flexibility as well as their learning capacity. 

"Our study offers new insights into how vocal and cognitive flexibility enables mammals to overcome size-related limitations of laryngeal sound production," said the researchers.

"This flexibility enables Asian elephants to exploit a frequency range spanning seven octaves within their communicative system."

The study is published in the journal <a href="https://bmcbiol.biomedcentral.com/">BMC Biology</a>.

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Asian elephants vibrate their lips like human brass players

There is a general rule for mammal vocalizations - the...

Nearly 17 million Americans had undiagnosed COVID-19 infections during the first wave of the <a href="https://www.earth.com/news/indoor-air-quality-standards-needed-to-prevent-pandemics/">pandemic</a>, according to a new study from <a href="https://www.sciencemag.org/">AAAS</a>. The experts report that by July of 2020, there were about five undiagnosed COVID-19 infections for every single diagnosed case.

The study reveals that women, people under the age of 45, African Americans, and city dwellers had the highest rate of undiagnosed infections. 

"The majority of patients infected with SARS-CoV-2 develop robust antibody responses against the viral spike protein, nucleocapsid protein, and the envelope protein that can be detected by serological testing," wrote the study authors.

"Antibodies against spike protein persist for months and can neutralize SARS-CoV-2. Frequently, these neutralizing antibodies bind to the receptor binding domain of the spike protein, but antibodies against the spike protein S2 domain have also been observed."

"To characterize the spread of SARS-CoV-2 infection in the United States, we evaluated seropositivity in a national survey of participants who had not previously been diagnosed with SARS-CoV-2 infection."

A team of researchers led by Heather Kalish of the National Institutes of Health analyzed blood samples from 8,058 undiagnosed adults. The samples were mainly collected from early May to the end of July 2020. 

The experts found that 304 of the participants harbored antibodies against the SARS-CoV-2 spike protein and its receptor binding domain. 

The results suggest that there was a much larger spread of COVID-19 than previously realized, which included undiagnosed infections in at least 4.6 percent of the U.S. population.

"This study demonstrates that spread of the SARS-CoV-2 virus in the US during the first six months of the pandemic was more widespread than has been suggested by data reporting diagnostic test-confirmed cases," wrote the researchers.

"These results, including the subgroup analysis, give us a previously undescribed view into the spread of the COVID-19 pandemic by more clearly identifying the large numbers of individuals with undiagnosed infections during the initial months of the pandemic. These data are of great importance as we consider the impact vaccination may have on the future course of the pandemic and plan for current and future available vaccines to be administered." 

"In addition, these data can also help us to better assess the public health measures taken during the pandemic and how to take the best approaches forward during any future public health emergencies."

The study is published in the journal <a href="https://stm.sciencemag.org/">Science Translational Medicine</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

&nbsp;

Millions of Americans had undiagnosed COVID-19 infections

Nearly 17 million Americans had undiagnosed COVID-19 infections during the...

Most models for viral transmission focus on humans spreading viruses that infect other humans. However, other factors may also be at play when it comes to transmission of viruses like the one that causes COVID-19, including tree pollen.

Researchers noticed a correlation between the increase of pollen and an increase in COVID-19 infections. In a new study from the <a href="https://www.aip.org/">American Institute of Physics</a>, Talib Dbouk and Dimitris Drikakis set out to investigate how pollen distribution may assist in the spread of SARS-COV-2 and other viruses.

The experts used a computer model to show how pollen moves in a willow. The computer model recreated a realistic tree producing pollen amidst a gathering of roughly 100 people, some of which were infected by COVID-19. 

"This included thousands of tree leaves and pollen grain particles, hundreds of stems and a realistic gathering of a crowd of about 100 individuals at about 20 meters from the tree," explained Dbouk.

As the tree pollen was caught in the wind and spread through the crowd of people, some of the particles attached to COVID-19 particles, carrying them farther than they would have traveled alone. 

Every grain of pollen can carry hundreds of virus particles, and a tree can populate a cubic meter of air with 1,500 grains on some days. The research suggests that pollen could have a significant impact on virus transmission, changing normal human to human dynamics.     

"In the case of high pollen grains concentrations in the air or during pollination in the spring, the social distance of 2 meters does not hold as a health safety measure for an outdoor crowd," explained the study authors. "Thus, the public authorities should revise the social distancing guidelines."

Although this study focused mainly on COVID-19 transmissions, the researchers hope that the paper increases interest in fluid dynamics of trees. 

They plan on carrying out more research on how these dynamics affect human respiration under different atmospheric conditions next.    

The study is published in the journal <a href="https://aip.scitation.org/journal/phf">Physics of Fluids</a>.

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Trees spread COVID-19 through pollen

Most models for viral transmission focus on humans spreading viruses...

In the mid-2030s, the frequency of <a href="https://www.earth.com/news/overtopping-threatens-the-future-of-coastal-habitats/">coastal</a> flooding will drastically increase across multiple regions in the United States, according to a new study from <a href="https://manoa.hawaii.edu/">UH Mānoa</a>. The projections show rapid increases in the number of high-tide flooding (HTF) days, as well as extreme months.

Study lead author Phil Thompson is the director of the UH Sea Level Center and assistant professor of Oceanography in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST).

"We expect the most rapid increases to be along U.S. Pacific and Gulf of Mexico coastlines, which includes Hawaii and other Pacific Islands. This is important, because this is the point at which high-tide flooding transitions from being primarily a local or regional issue and becomes a national issue affecting a majority of our nation's coastlines," said Professor Thompson. 

The researchers analyzed tide gauge data from 89 coastal locations around the United States, including 10 locations from Hawaii and the Pacific Islands. To project future occurrences of high-tide flooding, the team developed a new statistical technique that combines changes in tidal range with NOAA sea level rise scenarios for the 21st century.

The study shows that in the coming decades, sea-level rise will exacerbate the issue where it is already a recurring problem, while many more locations will begin to experience recurrent high-tide flooding.

The researchers found that annual cycles in tides can coincide with oceanographic anomalies to produce many high-tide flooding episodes over a short amount of time, leading to extreme months with clustered events.

"Scientists, engineers and decision-makers are accustomed to thinking about rare high-impact events, for example, a 100-year storm, but we demonstrate that it is important to plan for extreme months or seasons during which the number of flooding episodes, rather than the magnitude, is exceptional," said Professor Thompson.

The experts also determined that natural fluctuations in tidal range, which occur from one decade to the next, are responsible for alternately reducing and exacerbating the impacts of sea level rise.

"Understanding and communicating this phenomenon reduces the possibility of complacency and inaction during periods of reduced impacts and helps us be more prepared for periods when impacts will be heightened," said Professor Thompson. 

"As an island state with much of its infrastructure and economy vulnerable to sea level rise, these results are crucial to understanding how impacts from sea level rise will evolve in coming decades in Hawaii."

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

High-tide flooding will rapidly increase along the U.S. coastline

In the mid-2030s, the frequency of coastal flooding will drastically...

In a new study from <a href="https://www.ird.fr/">IRD</a>, researchers have found that coastal overtopping and subsequent <a href="https://www.earth.com/news/coastal-development-is-worsening-nuisance-flooding/">flooding</a> will become much more frequent in the coming decades. 

Hurricane Katrina served as a vivid example of coastal overtopping, where waves breach a natural or human-made barrier, usually resulting in massive damage. 

More recently, Typhoon Haiyan in Asia was the largest typhoon ever recorded and a reminder that the threat from overtopping - and from storms in general - is likely to increase, especially in the tropics. 

Global warming is set to make these events more frequent and stronger over time. Flooding is likely to increase as well. Almost a full 10 percent of the world’s human population lives in low lying coastal regions, which are the highest risk areas for overtopping. 

Human development on the coastline not only causes further damage to natural environments that are already threatened, but also raises risks to people and infrastructure.

The IRD team investigated the impact of wave overtopping on future flooding. The experts combined a digital Earth model with estimates of sea level rises. 

The researchers looked at the recent extreme weather events as well as long term patterns of wind driven waves and other phenomena to look at potential problems in the future and identify high risk areas. 

Some of the places most at risk of coastal overtopping are the Gulf of Mexico, the southern Meditteranean, west Africa, Madagascar and the Baltic. 

The scientists concluded that overtopping may also increase faster than the predicted rise in sea levels and that this risk is set to accelerate rather than increase at a steady rate. 

“The frequency of overtopping is accelerating exponentially and will be clearly perceptible as early as 2050, regardless of the climate scenario," said study co-author Rafaël Almar.

"By the end of the century, the intensity of the acceleration will depend on the future trajectories of greenhouse gas emissions and therefore the rise in sea-level. In the case of a high emissions scenario, the number of overtopping hours globally could increase fifty-fold compared with current levels.”

This is bad news, especially for the poorer regions directly threatened, such as Madagascar, where neither people nor government are prepared for the dangers ahead.

The study is published in the journal <a href="https://www.nature.com/ncomms/">Nature Communications</a>.

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

“Overtopping” threatens the future of coastal habitats

In a new study from IRD, researchers have found that...

Air pollution associated with burning fossil fuels was responsible for over one million premature deaths in 2017 alone, according to an international team of researchers led by <a href="https://wustl.edu/">Washington University</a>. The experts found that more than half of those deaths were attributable to coal.

Fine particle pollution (PM2.5) has become a global health crisis. The researchers note that PM2.5 has not only climbed to dangerous levels in the atmosphere, but can also be a hazard indoors from simply cooking on a stove.

"PM2.5 is the world's leading environmental risk factor for mortality. Our key objective is to understand its sources," said Professor Randall Martin.

Working in Professor Martin's lab, research associate Erin McDuffie used various computational tools to analyze a wealth of relevant data. The study has produced the most comprehensive dataset of air pollution emissions of its kind. 

The team was able to distinguish between various sources of air pollution, ranging from dust storms to energy production.

Overall, more than 20 distinct pollution sources were linked to human health issues based on the analysis of exposure to PM2.5 levels and health outcomes from the Global Burden of Disease.

The study shows that severe pollution is tied to different sources depending on the region of the world. McDuffie explained that while cookstoves and home-heating are still responsible for the release of particulate matter in many regions throughout Asia, energy generation remains a large polluter on the global scale.

"Previous studies end up having to use different emissions data sets or models all together," said McDuffie. "We can more directly compare results between countries." 

"We can even look at pollution sources in places that have implemented some mitigation measures, versus others that haven't to get a more complete picture of what may or may not be working."

In West sub-Saharan Africa, windblown dust accounted for nearly three quarters of the particulate matter in the atmosphere in 2017 compared to a global rate of just 16 percent. 

"Ultimately, it will be important to consider sources at the subnational scale when developing mitigation strategies for reducing air pollution," said McDuffie.

Even though the study confirms that air pollution is killing people prematurely worldwide, Professor Martin and McDuffie said their findings also have positive results for pollution monitoring.

"The good news is that we may be providing some of the first information that these places have about their major sources of pollution," said McDuffie. 

The study is published in the journal <a href="https://www.nature.com/ncomms/">Nature Communications</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

One million premature deaths linked to air pollution in 2017

Air pollution associated with burning fossil fuels was responsible for...

More than half of the world's rivers run dry each year In a new study led by <a href="https://www.mcgill.ca/">McGill University</a>, researchers have determined that more than half of the world's rivers and <a href="https://www.earth.com/news/californias-streamside-forests-are-threatened-by-water-management/">streams</a> stop flowing for at least one day per year. The experts found that between 51 and 60 percent of the 64 million kilometers of Earth's rushing waters run dry periodically.

The research highlights the need to change the general assumption that water flows in rivers and streams year-round. The study has also produced a map of non-perennial rivers that provides crucial baseline information for the assessment of future changes in river flow intermittence. North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be described as the northern subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the west and south by the Pacific Ocean. Because it is on the North American Tectonic Plate, Greenland is included as part of North America geographically. North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), about 16.5% of the Earth's land area and about 4.8% of its total surface. North America is the third-largest continent by area, following Asia and Africa,

"Non-perennial rivers and streams are very valuable ecosystems as they are home to many distinct species that are adapted to cycles of water presence and absence," said study first author Mathis Messager.

"These rivers can provide critical water and food sources for people and they play an important role in controlling water quality. But more often than not they are mismanaged or altogether excluded from management actions and conservation laws as they are simply overlooked."

Study co-senior author Professor Bernhard Lehner noted that given continued global climate and land use change, an increasingly large proportion of the global river network is expected to cease to flow seasonally over the coming decades.

"In fact, many formerly perennial rivers and streams, including sections of iconic rivers such as the Nile, the Indus and the Colorado River have become intermittent in the past 50 years due to climate change, land use transitions, or the temporary or permanent withdrawal of water for human use and agriculture."

The researchers analyzed long-term records of water flow in 5,615 locations around the world. The data included information on the hydrology, climate, and surrounding land cover at these locations. 

The experts determined that non-perennial rivers are most common in places where there is much more evaporation than rainfall. They also found that smaller streams have more variable flow, which makes them more likely to dry up periodically. 

Surprisingly, the study showed that non-perennial rivers occur in tropical climates - and even in the Arctic - where rivers freeze up for parts of the year.

The researchers estimate that more than half of the world's population lives in locations where the closest river or stream around them is non-perennial. 

"By mapping non-perennial rivers and streams, our study pushes for a recognition of their prevalence and ecological significance by the scientific community," said co-senior author Thibault Datry. 

"We hope that our study will trigger efforts to adequately manage these river ecosystems and halt attempts to exclude them from protective legislation."

The study is published in the journal <a href="https://www.nature.com/">Nature</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

More than half of the world's rivers run dry each year

More than half of the world's rivers run dry each...

It may seem like science fiction but researchers at <a href="https://ucsd.edu/">University of California, San Diego</a> proved it’s possible. The new study has recreated a complex bird song complete with pitch, tone and volume from nothing more than the bird’s <a href="https://www.earth.com/news/some-insects-have-more-than-200000-brain-cells/">brain</a> activity.

The research was focused on zebra finches, which are small, beautifully colored birds that are native to Australia. The experts implanted silicone chips into the birds brains to record the brain activity controlling vocal muscles while they sang. 

The readings were then fed into a computer algorithm where computers recreated the bird songs. In research such as this, the test animals are typically euthanized when the study has concluded. 

The scientists hope to sacrifice a few birds for the good of disabled people by applying this research to humans eventually. The idea is to build a "vocal prosthetic" where someone can recreate their own verbal words simply by thinking them. 

“The current state of the art in communication prosthetics is implantable devices that allow you to generate textual output, writing up to 20 words per minute…Now imagine a vocal prosthesis that enables you to communicate naturally with speech, saying out loud what you're thinking nearly as you're thinking it. That is our ultimate goal, and it is the next frontier in functional recovery," explained study senior author Timothy Gentner.

While it may seem like a stretch to jump from bird song to human speech, anyone who has listened on a spring morning to the cacophony knows that bird’s songs can be quite complex. In fact, the researchers say that there are many similarities between the two. 

Previous research shows that if you delay the sound of a person’s voice, playing it back just a bit later, they will start to stutter. The same is true of birds when they sing.

Ultimately, the researchers hope that their prosthetic will be close in timing to actual speech. Something that can be reacted upon as we react naturally to hearing our own voice. 

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mind reading technology recreates bird song from brain waves

It may seem like science fiction but researchers at University...

Thale,Cress,(arabidopsis,Thaliana),Blossoms,And,Buds,Macro,Picture

The scientific exploration of the natural world is a conundrum. We’ve scaled the highest <a href="https://www.earth.com/news/flood-risk-could-triple-in-the-high-mountains-of-asia/">mountains</a> and discovered trash already waiting for us on the bottom of the ocean. Science has gathered so much information that sometimes, it seems there should be little left to learn. 

There are some aspects of the natural world especially familiar to science. Like the proverbial guinea pig, scientists come back to some organisms again and again to test ideas with potential broad applications. Thale cress (Arabidopsis thaliana) is one of those organisms for botanists. 

Thale Cress is a pretty but nondescript little plant with spindly stalks bearing simple, white flowers. The plant is considered a weed, found in disturbed areas in its native home of Africa and Eurasia. First described by science in the 16th century, Thale Cress has become popular in genetic experiments since the 1940s. 

Rather than asking questions about the plant itself, most research has focused on using Arabidopsis thaliana as a model organism to ask more general questions about genetics, such as their impact on development and physiology. While it seemed that the research had surpassed understanding the modest thale cress, scientists recently discovered that we still have more to learn. 

Since 2008, Dr. Timothy Gookin, a postdoctoral researcher with Sarah Assmann’s lab at <a href="https://www.psu.edu/">Pennsylvania State University</a>, has been working with thale cress. Considering the amount of study already directed at the thale cress, what he discovered was surprising - a new piece of plant anatomy dubbed the "cantil." 

“It took over 12 years of experimentation to really get a grasp on what we were seeing and to understand how cantils were regulated," said Dr. Gookin. "This study required the growth of 3,782 plants to full maturity and the manual inspection of over 20,000 flower-bearing stalks in 34 unique plant lines”

The name cantil itself comes from the unique function of the structure. Under rare circumstances such as short day length, cantils develop, seemingly as a counter balance to hold up flowers. The unique feature connects to the flower’s stem and hangs like a cantilever.    

"One speculative interpretation is that the cantil represents a highly repressed ancestral linkage between different types of flowering plant architectures; the multiple layers of genetic and environmental factors that regulate cantil development are certainly quite striking," said Dr. Gookin.

The study is published in <a href="https://www.biologists.com/">The Company of Biologists</a> journal <a href="https://journals.biologists.com/dev">Development</a>.

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Experts discover a new body part in plants

The scientific exploration of the natural world is a conundrum....

Satellite imagery has revolutionized the way we see the world. The international charter “Space and Major Disasters” in particular uses satellite imagery to help take a closer look at natural <a href="https://www.earth.com/news/social-media-posts-predict-economic-recovery-after-natural-disasters/">disasters</a> that may be hard to analyze without such a large view. 

On February 7, 2021 about 27 million metric tons of rock and ice fell from the flank of Ronti Peak in the Chamoli District of the Uttarakhand region in India. The debris plowed down the Ronti Gad, Rishiganga and Dhauliganga river valleys, sparking a humanitarian crisis. Over 200 people were killed and two under construction hydroelectric plants were destroyed. 

This tragedy activated the “Space and Major Disasters” services which provided free satellite images of the catastrophe as it unfolded. Combined with other freely available imagery, scientists were able to look closely at the parameters of the calamity. Elevation change, volume and distance travelled were able to be quantified. 

It was initially thought that the Chamoli disaster might be caused by a glacier lake outburst flood but this was quickly ruled out. A new report from the <a href="http://www.esa.int/">European Space Agency</a> describes how a team of 53 scientists and experts reconstructed the events as they happened, incorporating video footage from bystanders with the satellite images. 

The analysis found that, in fact, the disaster was caused by an avalanche which formed near a Bergschrund. A Bergschrund is a crevasse that forms where ice sheets meet with a rock face on a mountain. Copernicus Sentinel-2 images show that the Bergschrund in question had opened up earlier and an avalanche had deposited debris in 2016. 

Overall, this approach to analysis shows that satellites may play a role in predicting the possibilities of avalanche threats in the future. It’s likely, the scientists involved in the study point out, that such natural disasters will become more common as the earth warms up.

“The rapid increase in the number of satellites orbiting Earth allowed our team to understand the basics of what happened in a matter of hours," said study lead author Professor Dan Shugar of the University of Calgary.

"We now have access to satellites that image every part of Earth every day - sometimes even multiple times per day - and this has really revolutionized how we do this sort of science.”

The study was published in the journal <a href="https://www.sciencemag.org/">Science</a>. 

---

By <a href="http://zachfitzner@yahoo.com">Zach Fitzner </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Satellites confirm: Avalanche caused the Chamoli Disaster

Satellite imagery has revolutionized the way we see the world....

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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.

<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://youtu.be/Fi2OeEwuzRM?si=vTyd2m9FMmtyWkex
</div></figure>







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



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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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