Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the largest man-made reservoir in California, Lake Shasta, which filled to nearly 100 percent capacity in May 2023. This is the highest level that Shasta has reached in four years.&nbsp;



"Since 2019, a prolonged period of extreme drought resulted in dwindling reservoir levels. In the early months of 2023, heavy rains and meltwater from an above-average mountain snowpack caused a notable turnaround," said NASA.



"Lake Oroville, the state’s second-largest reservoir, was also near capacity on May 29, at 97 percent full. Both Lake Oroville and Shasta Lake are critical not only for water storage, but also for flood control, recreation, irrigating cropland in the Central Valley, and preventing saltwater intrusion into the Sacramento-San Joaquin Delta."



NASA noted that full reservoirs do not ensure plentiful water for years into the future, and that the past four years are a testament to how drastically reservoirs can change in a short amount of time.&nbsp;



"The California DWR is collaborating with other agencies to incorporate better forecasting and observation technologies in order to optimize water releases."



Image Credit: NASA Earth Observatory&nbsp;



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Lake Shasta reaches nearly 100 percent capacity

Today's Image of the Day from NASA Earth Observatory features...

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Quebec, where about 160,000 hectares have burned since the start of the year.



"An unusually intense start to Canada’s wildfire season filled skies with smoke in May 2023. Then, at the beginning of June, scores of new fires raged in the central Canadian province of Quebec, some of which were ignited by lightning," says NASA.



"The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this view of smoke billowing from the fires on June 3. Shortly after the fires started, about 5,000 residents were ordered to evacuate near the city of Sept-Îles in the province’s east."&nbsp;



"As the fires grew, evacuations were extended to an additional 9,000 people in surrounding communities and in western Quebec’s Val-d’Or and Normétal municipalities. As of June 5, more than 150 wildfires were active in Quebec."



Image Credit: NASA Earth Observatory&nbsp;



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Forest fires rage in Quebec

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the west coast of South America. The photo was captured by an astronaut aboard the International Space Station while orbiting over the Atacama Desert and Central Andes Mountains near the border of Bolivia, Peru, and Chile.



"Over the Pacific Ocean, marine stratocumulus clouds develop over cold water that rises from the ocean depths as the Peru current (Humboldt current) flows north along the west coast of South America," says NASA. "The coastline is marked by low mountains that are dissected by canyons carved by rivers that flow down the western side of the Andes."



The Atacama Desert receives less than 0.2 inches of rain per year on average. According to NASA, this dry environment provides an ideal setting to conduct Mars analog studies.



"Active and inactive volcanoes comprise the Central Andean Volcanic Arc within the Atacama Desert and Andes Mountains. One of the inactive volcanoes visible in this photo is Bolivia’s Nevado Sajama, which has a maximum elevation of 6,542 meters (21,463 feet). Nevado Sajama and other volcanoes in the region often have glaciers and snow cover due to their high elevation."



Image Credit: NASA Earth Observatory&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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The west coast of South America

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features an astronaut photograph of the Cape Cod peninsula, located in the easternmost portion of Massachusetts. The peninsula extends into the Atlantic Ocean and is a significant feature of the East Coast of the United States.



Cape Cod peninsula is characterized by its beaches, villages, and seafood. It's a popular tourist destination, particularly in the summer months, with people visiting for its beautiful landscapes and unique culture.



Cape Cod consists of 15 towns, including Provincetown, Hyannis, Falmouth, and Chatham. Each town has its own distinctive character and attractions. For example, Provincetown, located at the tip of the peninsula, is known for its vibrant LGBTQ+ scene, while Hyannis is famous as a ferry gateway to the islands of Martha's Vineyard and Nantucket.



The Cape Cod National Seashore, a national park covering much of the Outer Cape, including the entire east-facing coast, provides opportunities for hiking, biking, and beachgoing.



Historically, Cape Cod was a landmark for early explorers of the Americas. It was among the first places settled by the English in North America in the Pilgrim Fathers' era, and it played a key role in the early history and development of the United States.&nbsp;



Today, the Cape's history is preserved in numerous museums, historic sites, and lighthouses. In addition, a variety of wildlife can be found in the region, such as whales, seals, and many species of birds.



"The variety of ecosystems within Cape Cod National Seashore sustain over 450 species of amphibians, reptiles, fish, birds, and mammals, including 32 species that are rare or endangered," says NASA. "One of those species is the American oystercatcher, a large shorebird that uses a knife-like bill to eat shellfish."



Image Credit: NASA Earth Observatory&nbsp;



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Cape Cod peninsula in the northeastern United States

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Amundsen Gulf in northern Canada, where ice is typically covered with ice that is fastened to surrounding coastlines. According to NASA, the breakup of this ice tends to be rapid when the melting season arrives in spring.



"Patches of fast ice remained in the eastern part of the gulf in late May, but summer weather will ultimately clear it away as well. The Amundsen Gulf, the western entrance to the Northwest Passage, is usually ice-free by August," says NASA.



Walt Meier, a senior research scientist at the National Snow and Ice Data Center, said that winds play an important role in the breakup of the ice. He noted that an area of low pressure centered south of the gulf prior to the breakup fueled strong easterly winds and large waves that broke up the ice and sent chunks of it drifting west.&nbsp;



This year's spring breakup occurred earlier than usual, which aligns with the overall trend in the Beaufort Sea region in recent decades, noted NASA.



“Over a period of two decades, the Amundsen Gulf had the highest interannual variability of anywhere across the entire Northwest Canadian Arctic,” said Eleanor Wratten, a researcher at Northumbria University and the lead author of an analysis of decades of MODIS observations of fast ice in the Northwest Canadian Arctic.&nbsp;



“We saw the timing of breakup change considerably from one year to the next, but the general pattern looked similar to what you see here. Ice usually remains in the southern bays the longest, with breakup veering toward the strait in the southeastern portion of the gulf.”



The image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on May 30, 2023.



Image Credit: NASA Earth Observatory&nbsp;



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Spring ice breakup in the Amundsen Gulf

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Nova Scotia, where unusually large fires have led to the evacuation of thousands of people. The photograph, which was captured by an astronaut on the International Space Station, shows smoke rising from a fire near the town of Shelburne on May 29, 2023.



"By the morning of May 31, after four days of burning, the fire had scorched 17,000 hectares (66 square miles) near the southern tip of Nova Scotia," says NASA. "It became the largest forest fire in the province’s history, according to CBC Nova Scotia, exceeding the area burned by a fire in Guysborough County over six days in June 1976."



"Fires have burned in Canada for weeks, as the western part of the country experienced a record-breaking streak of hot weather in mid-May."&nbsp;



"Several regions in Canada also had an abnormally dry spring; Nova Scotia received about half of the usual amount of rainfall in April. Authorities classified both the Halifax and Shelburne County fires as uncontrolled on May 31 and expected the fires to grow as dry and windy conditions continued."



Image Credit: NASA Earth Observatory&nbsp;



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Smoke rises from fires in Nova Scotia

Lake St. Clair of the U.S. and Canada Today's Image of the Day from <a href="https://www.nasa.gov/">NASA</a> features Lake St. Clair, which connects Lake Huron to Lake Erie through the St. Clair and Detroit rivers. 

The lake covers an area of about 425 square miles, and has an average depth of 3.5 meters. The United States and Canada both have a deep shipping channel through the lake. 

Canada is a country in the northern part of <a href="http://www.earth.com/news/two-migrations-north-america/">North America</a>. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering 9.98 million square kilometres (3.85 million square miles), making it the world's second-largest country by total area. Its southern border with the United States, stretching some 8,891 kilometres (5,525 mi), is the world's longest bi-national land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Lake St. Clair of the U.S. and Canada also there as shown above in image.
As a whole, Canada is sparsely populated, with most of its land area dominated by forest and tundra. Its population is highly urbanized, with over 80 percent of its inhabitants concentrated in large and medium-sized cities, and 70 percent residing within 100 kilometres (62 mi) of the southern border. Canada's climate varies widely across its vast area, ranging from Arctic climate in the north to hot summers in the southern regions, with four distinct seasons.

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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

Image Credit: NASA

Lake St. Clair of the U.S. and Canada

Scientists have uncovered a newly discovered plant-eating <a href="https://www.earth.com/news/new-species-of-sauropod-dinosaur-discovered/">dinosaur</a>, Iani smithi, that appears to be a species' "last gasp." This dramatic event took place during a period when Earth's warming climate was forcing profound shifts in global dinosaur populations.



Unearthed from Utah's Cedar Mountain Formation, the majority of the juvenile dinosaur's skeleton - encompassing its skull, vertebrae, and limbs - was successfully retrieved.&nbsp;



The specimen is named after Janus, the two-faced Roman god of change. It serves as a tribute to its place as an early ornithopod, a group of dinosaurs that would eventually pave the way for well-known duckbill dinosaurs like Parasaurolophus and Edmontosaurus.



<h2 id="h-iani-smithi-lived-during-a-transformative-time-on-earth">Iani smithi lived during a transformative time on Earth</h2>



The striking feature of Iani smithi is its powerful jaw, specially equipped with teeth perfect for chomping through robust plant material. This creature roamed the region now known as Utah approximately 99 million years ago during the mid-Cretaceous period.



This era was one of significant transformation, affecting dinosaur populations considerably. Enhanced levels of atmospheric carbon dioxide caused the Earth's temperature to rise and sea levels to swell, leaving dinosaurs confined to increasingly smaller landmasses.&nbsp;



So intense was the warmth that rainforests flourished at the poles while flowering plant life began to dominate coastal regions, replacing the traditional food sources for herbivores.



<h2 id="h-most-dinosaur-species-were-vanishing-when-iani-smithi-arrived">Most dinosaur species were vanishing when Iani smithi arrived</h2>



As the mid-Cretaceous period unfolded, giant plant-eating sauropods, once the reigning titans of North American landscapes, were vanishing along with their allosaurian predators. Concurrently, smaller plant eaters like early duckbills and horned dinosaurs were arriving from Asia, accompanied by feathered theropods such as tyrannosaurs and enormous oviraptorosaurs.



The discovery of Iani smithi is momentous, not just for its novelty but also due to its infrequent appearance in the North American fossil record and its unique place in dinosaur history.



"We had a stroke of luck finding Iani," says Lindsay Zanno, head of paleontology at the North Carolina Museum of Natural Sciences and associate research professor at <a href="https://www.ncsu.edu/">North Carolina State University</a>.&nbsp;



"We knew something like it inhabited this ecosystem because we had come across isolated teeth, but we didn't anticipate finding such an impressive skeleton, particularly from this era. Having a nearly complete skull was crucial for piecing together the story."



Zanno and her team, employing the well-preserved skeleton, have been examining the evolutionary relationships of Iani, expressing surprise and slight doubt at their findings.



"Upon analysis, we identified Iani as an early rhabdodontomorph, an ornithopod lineage primarily known from Europe," explained Professor Zanno. "Lately, paleontologists have suggested that Tenontosaurus, a North American dinosaur as prevalent as cattle in the Early Cretaceous, along with some Australian dinosaurs, belong to this group. If Iani is indeed a rhabdodontomorph, it poses several fascinating questions."



<h2 id="h-iani-smithi-may-have-been-the-last-in-a-successful-dinosaur-lineage">Iani smithi may have been the last in a successful dinosaur lineage</h2>



One of the central questions raised is whether Iani smithi could represent the final gasp, a final witness to the demise of a once successful lineage. Zanno believes that examining this fossil in light of environmental and biodiversity shifts during the mid-Cretaceous will yield further insights into our planet's history.



"Iani might be the last surviving member of a lineage of dinosaurs that once thrived here in North America but were eventually supplanted by duckbill dinosaurs. Iani was alive during this transition - so this dinosaur really does symbolize a changing planet," said Professor Zanno.



"This dinosaur stood on the precipice, able to look back at the way North American ecosystems were in the past, but close enough to see the future coming like a bullet train. I think we can all relate to that."



As this dinosaur signifies a significant transition, it is fittingly named after Janus, the two-faced god symbolizing transitions.



<h2 id="h-glimpse-into-a-critical-period-in-earth-s-history">Glimpse into a critical period in Earth’s history</h2>



The discovery of Iani smithi and the ensuing research offers a unique glimpse into a critical period in Earth's history, when rapid climatic changes transformed landscapes, ecosystems, and the organisms that lived in them.&nbsp;



Studying these ancient creatures provides scientists with a powerful tool for understanding how life on Earth has evolved in response to such changes, and perhaps how it may continue to do so in the face of modern-day climate change.



This landmark research has been published in <a href="https://journals.plos.org/plosone/">PLOS ONE</a> and received support from the National Science Foundation.



As scientists continue to unearth and examine fossils like Iani smithi, we are gifted with a deeper understanding of our planet's history. In the face of today's environmental challenges, this knowledge proves invaluable.&nbsp;



<h2 id="h-more-about-the-mid-cretaceous-period">More about the mid-Cretaceous period&nbsp;</h2>



The mid-Cretaceous period, dating from around 125 to 90 million years ago, was a time of significant change for life on Earth.



This era, part of the larger Cretaceous period that spanned from about 145 to 66 million years ago, saw significant shifts in global climates, landmasses, and ecosystems, resulting in the evolution of new species and the extinction of others. It's best known for being the last era in which dinosaurs roamed the Earth, culminating in a mass extinction event at the end of the period.



<h3 id="h-much-warmer-climate">Much warmer climate</h3>



From an environmental perspective, the mid-Cretaceous period was marked by a significantly warmer climate than we have today. This climate change was due in large part to high levels of atmospheric carbon dioxide, likely resulting from increased volcanic activity.&nbsp;



During this time, there was no polar ice, and even the polar regions enjoyed a tropical or subtropical climate. This warmth led to higher sea levels, with shallow seas covering parts of the continents.



<h3 id="h-plants-began-to-flourish">Plants began to flourish</h3>



The mid-Cretaceous was also a time of flourishing plant life. It witnessed the rise of the angiosperms, or flowering plants, which rapidly diversified and spread across the globe, significantly altering ecosystems and providing new food sources for various herbivorous dinosaurs.&nbsp;



The first bees appeared during this period too, likely evolving alongside these flowering plants in a mutual relationship of pollination.



<h3 id="h-new-types-of-dinosaurs-emerged">New types of dinosaurs emerged</h3>



As for animal life, the mid-Cretaceous was a time of significant shifts. While dinosaur groups like the large, long-necked sauropods were beginning to decline, new kinds of dinosaurs were on the rise.&nbsp;



This period saw the emergence of new types of theropods like tyrannosaurs, which would later give rise to the iconic Tyrannosaurus rex near the end of the Cretaceous. Meanwhile, feathered dinosaurs and early birds continued to evolve and diversify.



In the oceans, the mid-Cretaceous period saw the rise of large marine reptiles like mosasaurs and pliosaurs, along with an increased diversity of ammonites and mollusks. At the same time, the first true birds began to appear, and mammals, although still small and largely nocturnal, started to diversify into a wider array of forms.



Overall, the mid-Cretaceous was a time of considerable global change, with fluctuating climates, shifting landmasses, and evolving ecosystems setting the stage for the world we know today. It provides a fascinating lens through which to study how life on Earth responds to large-scale environmental changes over time.



Image Credit: Jorge Gonzalez



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Dinosaur named Iani smithi lived during a time of major transition

Scientists have uncovered a newly discovered plant-eating dinosaur, Iani smithi,...

Shallow lakes and ponds might seem innocuous in our landscape, but they have been found to emit substantial volumes of greenhouse gases into the atmosphere. Our understanding of the emissions from these water bodies, however, has been muddled due to significant variations in their <a href="https://www.earth.com/news/epa-plans-to-eliminate-greenhouse-gas-emissions-from-power-plants-by-2040/">emissions</a>.



A recently conducted study led by <a href="https://www.cornell.edu/">Cornell University</a> offers fresh insights into this issue. This study aimed to quantify methane and carbon dioxide emissions from 30 small lakes and ponds, each less than an acre in size. These bodies of water were situated in temperate regions across Europe and North America. Intriguingly, the team found that it was the smallest and shallowest of these bodies of water that demonstrated the greatest emission variability over time.



"These small and shallow bodies of water, though often overlooked, are now gaining prominence in the larger climate change narrative," said study senior author Professor Meredith Holgerson.



The findings of this research have critical implications for the calibration of climate models. "The paper points to patterns across a broad geographic range, such that we can actually get in and predict which water bodies are going to vary and will be most variable," noted Nicholas Ray, a postdoctoral researcher in Holgerson’s lab. Furthermore, the study underscores the urgent need to study these smaller bodies of water more meticulously.



Earlier research led by Holgerson's team suggested that these shallow lakes and ponds could contribute about five percent of global methane emissions to the atmosphere. However, without precise measurements from a multitude of water bodies, the actual contribution could fluctuate between half to twice this figure.



Understanding the emission dynamics from these water bodies is crucial since both carbon dioxide and methane act as greenhouse gases. Notably, methane is 25 times more effective than carbon dioxide at trapping heat in our atmosphere.



For the study, each water body was sampled three times during the summers of 2018 and 2019. Sampling was done at three different locations, including the deepest point and two spots on opposite ends, while ensuring that these were not too close to the shoreline.



Ray revealed a key finding that "the smaller the system is, in regard to surface area, the higher emissions are likely to be." For carbon dioxide, the samples were consistent across the entire water body. This indicated that just one sample could accurately predict the carbon dioxide emissions for the whole body of water. However, for methane, multiple samples from different locations were required to measure emissions accurately.



Additionally, the variability in carbon dioxide emissions seemed to be influenced heavily by the amount of plant life in the water. Meanwhile, the variability in methane emissions was more driven by the water depth, which could be linked to stratification in the water column.



Among other applications, this study paves the way for building more ponds as a part of New York State's climate mitigation strategy. These ponds could also aid farmers in better managing droughts.



"We’re working to identify how ponds can be built, or if there are simple management strategies people can employ, to minimize emissions," Ray said, revealing the proactive approach taken to utilize this new information.



<h2 id="h-more-about-climate-models">More about climate models</h2>



Creating climate models is an intricate and fascinating process. These models are computer programs that simulate the interactions of the atmosphere, oceans, land surface, and ice. They are used by scientists to better understand the Earth's climate and how it might change in the future.



Climate models work by dividing the planet into a 3D grid, which can focus on a specific area or cover the globe. Each grid box, and the layers above and below it, represents a chunk of the atmosphere, ocean, or land.&nbsp;



The model then solves equations that describe the fluid motion and thermodynamics of the atmosphere and oceans, the transmission of sunlight through the atmosphere and oceans, the exchange of heat with the land and ice surface, and many other physical processes.



<h3 id="h-types-of-climate-models">Types of climate models</h3>



There are several types of climate models, each serving a different purpose. For instance, simple climate models can be used to look at the Earth's energy balance. These models can give a broad-brush view of the climate system and are useful for providing a rough idea of how changes in the Earth's energy budget can affect global temperatures.



At the other end of the scale are complex climate models, also known as general circulation models (GCMs). These split the atmosphere, oceans, and land into many layers and boxes, allowing for the detailed study of individual climate processes and their interactions.



Some GCMs include a detailed representation of the carbon cycle, atmospheric chemistry, ice flow dynamics, and vegetation dynamics, which make them coupled climate-carbon-chemistry models. These models can investigate not just how climate change influences the carbon cycle and other biogeochemical cycles, but also how feedbacks from these cycles may impact the climate system.



<h3 id="h-improving-accuracy-by-incorporating-more-data">Improving accuracy by incorporating more data</h3>



These models have become increasingly sophisticated, even incorporating elements such as cloud formation, vegetation cover changes, and the impact of volcanic emissions. However, climate models are not perfect and have limitations.&nbsp;



For instance, there are uncertainties around how to accurately represent processes like cloud formation and precipitation at the scale of a grid box, and how to represent the indirect effects of aerosols.



Nevertheless, despite their limitations, climate models are essential tools for scientists, providing our best means of projecting future climate change scenarios based on different greenhouse gas emission pathways.



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Measuring greenhouse gas emissions from ponds improves climate predictions

Shallow lakes and ponds might seem innocuous in our landscape,...

An alarming new study warns that the Arctic is rapidly heading towards ice-free summers, a scenario previously thought to be avoidable. Even with significant efforts to cut greenhouse gas emissions, scientists predict that the polar region will experience its first summer without sea ice as early as 2030.&nbsp;



This research, just published in the journal <a href="https://www.nature.com/articles/s41467-023-38511-8">Nature Communications</a>, paints a grim picture of the future of Arctic Sea ice, which has been witnessing an accelerated shrinkage over the last two decades.



"The Arctic summer sea ice is past the point of no return," said Professor Dirk Notz of the <a href="https://www.uni-hamburg.de/en.html">University of Hamburg</a>, Germany, a member of the research team.&nbsp;



<h2 id="h-arctic-ice-has-been-declining-for-decades">Arctic ice has been declining for decades</h2>



Arctic ice, which follows a cycle of accumulation during the winter and melting in the summer, reaching its lowest levels in September, has been gradually decreasing for decades. But the rate of this decrease has dramatically sped up in the past 20 years.



Notably, the new findings contradict the latest report from the UN's <a href="https://www.ipcc.ch/">Intergovernmental Panel on Climate Change</a> (IPCC). The IPCC report had previously estimated that the Arctic would be practically ice-free in September around mid-century if we failed to curb emissions. But the new study suggests the ice loss is happening at a much faster pace.



The research team, comprising scientists from South Korea, Canada, and Germany, relied on satellite observations of Arctic Sea ice over the last 40 years and the best climate models to analyze the rate of ice loss. They primarily attribute the loss to greenhouse gas emissions.&nbsp;



Study lead author Professor Seung-Ki Min of <a href="https://international.postech.ac.kr/">Pohang University of Science and Technology</a> in South Korea expressed surprise at the inevitable loss of Arctic summer sea ice, irrespective of our emission reduction efforts.



<h2 id="h-number-of-ice-free-arctic-months-will-continue-to-increase">Number of Ice-free Arctic months will continue to increase</h2>



Once the Arctic summers become ice-free, the winter buildup of sea ice will slow down significantly, warns Min. As temperatures rise, the Arctic will likely stay free of sea ice further into the colder season.&nbsp;



Under the scenario of continued fossil fuel usage and increasing planet-warming pollution, also known as the "higher emissions pathway," the study predicts the Arctic could lose all sea ice from August until as late as October before the 2080s.



Professor Notz noted that scientists have been cautioning about the loss of Arctic summer <a href="https://www.earth.com/news/arctic-sea-ice-algae-heavily-contaminated-with-microplastics/">sea ice</a> for decades. This loss represents the first significant casualty of the Earth system due to global warming. "People didn't listen to our warnings," said Notz.



The situation in the Arctic is especially ugent, given that it has warmed four times faster than the rest of the world over the past several decades, according to a 2022 study. <a href="https://www.nasa.gov/">NASA</a> data reveals that annual&nbsp; September sea ice is shrinking at a rate of 12.6 percent per decade.



<h2 id="h-impact-will-be-felt-around-the-world">Impact will be felt around the world</h2>



The repercussions of an ice-free Arctic will be felt globally. The bright white ice currently reflects solar energy away from the Earth, but once it melts, the darker ocean surface will absorb more heat, leading to further warming - a feedback loop known as "Arctic amplification." Additionally, the diminishing sea ice could disrupt global weather patterns far beyond the Arctic region.



"We need to brace for a warmer Arctic very soon," said Min. He suggests that Arctic warming could trigger weather extremes such as heatwaves, wildfires, and floods in Northern mid- and high latitudes. The earlier onset of an ice-free Arctic also means that these extreme events will occur sooner than anticipated.



An ice-free Arctic could also catalyze an increase in commercial shipping, leading to more emissions and pollution in the region. Min compared the Arctic sea ice to the body's immune system, emphasizing that, without this protector, the Arctic's condition could rapidly deteriorate. The study suggests that the Arctic has reached a worrying "tipping point," and the region is on the verge of becoming "seriously ill."



Mika Rantanen, a researcher with the Finnish Meteorological Institute and lead author of the 2022 study, praises the methodology of the newly published research. Rantanen, not involved in this particular study, said it benefited from "novel and state-of-the-art methodology" to predict when the Arctic will be ice-free.



Rantanen said the research brings a high degree of certainty in attributing the sea ice loss to increased greenhouse gases. The striking result isn't just the link between sea ice loss and greenhouse gas increases, which has already been largely established, but the prediction of an ice-free Arctic a decade earlier than previously expected, explained Rantanen.



<h2 id="h-the-arctic-has-officially-reached-a-tipping-point">The Arctic has officially reached a tipping point</h2>



In light of these findings, it's clear that the situation in the Arctic is dire, and the region has reached a tipping point. The Arctic Sea ice, much like an immune system that protects against harmful influences, is in jeopardy. "Without the protector, the Arctic's condition will go from bad to worse quickly," said Min.



This new research is a sobering reminder that our planet's northernmost region is undergoing rapid change, which will undoubtedly have far-reaching consequences. The predictions suggest not just an environmental catastrophe but also the potential for geopolitical and economic shifts as new shipping routes open up.



As scientists continue to monitor these changes and their implications, one message is clear: the world needs to act decisively to mitigate the worst effects of climate change. The fate of the Arctic sea ice may be sealed, but there are still many climate battles to be fought, and won. The key is to listen to the warnings of scientists and turn them into policies and practices that protect our planet's fragile ecosystems.



<h2 id="h-more-about-the-arctic-sea-ice-melt">More about the Arctic Sea ice melt&nbsp;</h2>



Arctic sea ice is a critical part of our planet's ecosystem, and its rapid decline due to climate change can have far-reaching implications.



Firstly, it's essential to understand that the Arctic sea ice behaves like a gigantic mirror. It reflects about 80% of the sunlight that reaches it back into space, helping to keep the planet cool. This phenomenon is known as the albedo effect.&nbsp;



However, as the ice melts, it reveals the darker ocean surface, which absorbs around 90% of the sunlight, turning it into heat and contributing to global warming. This is a feedback loop known as "Arctic amplification." The more the ice melts, the more sunlight gets absorbed, leading to more warming and further melting of the ice – a vicious cycle that accelerates climate change.



<h3 id="h-rising-sea-levels">Rising sea levels</h3>



The melting of Arctic sea ice also contributes to rising sea levels. While the melting of sea ice itself doesn't contribute directly to sea level rise—since it is already floating on the ocean and displaces an equivalent volume of water—melting ice on land, such as the Greenland ice sheet, does.&nbsp;



As Arctic temperatures rise, the rate of melt from these ice sheets increases, which can significantly contribute to global sea level rise and pose a threat to coastal communities.



<h3 id="h-disruption-of-weather-patterns">Disruption of weather patterns&nbsp;</h3>



Changes in Arctic sea ice can disrupt weather patterns far beyond the Arctic region. Some researchers suggest that the warming Arctic is causing shifts in the jet stream, a band of high-altitude wind that influences weather patterns. These shifts could potentially lead to more frequent and severe weather events, such as heatwaves, droughts, and storms, in parts of North America, Europe, and Asia.



<h3 id="h-geopolitical-implications">Geopolitical implications</h3>



An ice-free Arctic could also have significant geopolitical implications. New shipping routes would open up as ice recedes, potentially leading to disputes over rights to these passages and access to untapped natural resources beneath the Arctic Ocean. While this might be seen as a commercial opportunity, increased shipping and exploration could lead to more emissions and pollution in an already fragile environment.



<h3 id="h-significant-disruption-to-ecosystems">Significant disruption to ecosystems&nbsp;</h3>



Furthermore, Arctic ecosystems will be significantly affected. Polar bears, seals, and several species of birds rely on sea ice for their habitat and hunting grounds. As ice recedes, these species face the threat of extinction. Indigenous people who rely on these animals for their sustenance and whose culture is intimately tied to the ice will also be profoundly affected.



The rapid decline of Arctic sea ice is a bellwether for global warming. It's a tangible, visible indicator of climate change that underscores the urgent need for climate action. The impacts of its loss will be felt worldwide, affecting everything from global weather patterns to ecosystems to human communities.



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Ice-free Arctic summers could be the new normal by 2030

An alarming new study warns that the Arctic is rapidly...

Community of stem group eukaryotes

Diving deep into the realm of life's origin, scientists have recently unearthed an enthralling discovery. They have found evidence of an ancient "lost world" - microscopic creatures that inhabited Earth's waterways as far back as 1.6 billion years ago.&nbsp;This discovery is set to redefine our understanding of the earliest known lifeforms on <a href="https://www.earth.com/news/humans-have-surpassed-almost-every-safe-limit-to-keep-earth-habitable/">Earth</a> and their connection to our ancestral lineage.



These ancient organisms, labeled as the "Protosterol Biota," belong to a broad family of life known as eukaryotes. Unlike their simpler bacterial cousins, eukaryotes exhibit a more intricate cell structure. Their cells house vital components such as mitochondria, famously dubbed the "powerhouse" of the cell, and a nucleus serving as the "control and information center."



Eukaryotes of today have adopted various forms - fungi, plants, animals, and single-celled organisms like amoebae are some of the examples. Interestingly, humans, along with all other nucleated beings, trace their ancestry back to the Last Eukaryotic Common Ancestor (LECA), an organism that existed more than 1.2 billion years ago.



<h2 id="h-protosterol-biota-may-have-been-earth-s-first-predators">Protosterol Biota may have been Earth’s first predators</h2>



However, this recent discovery, which was published in the journal <a href="http://dx.doi.org/10.1038/s41586-023-06170-w">Nature</a>, unveils that the Protosterol Biota thrived even before LECA. Scientists from <a href="https://www.anu.edu.au/">Australian National University</a> (ANU), who made this revelation, propose that these organisms might have been the Earth's inaugural predators.



Dr. Benjamin Nettersheim, a former PhD student at ANU now at the University of Bremen in Germany, noted that these ancient beings were quite prolific in marine ecosystems around the world. He stated, "Molecular remains of the Protosterol Biota detected in 1.6-billion-year-old rocks appear to be the oldest remnants of our own lineage – they lived even before LECA."



"Scientists have long searched for fossilised evidence of these early eukaryotes, but their physical remains are extremely scarce," explained Dr. Nettersheim. "Our study flips this theory on its head. We show that the Protosterol Biota were hiding in plain sight and were in fact abundant in the world’s ancient oceans and lakes all along."



Further elucidating on the nature of these ancient organisms, Professor Jochen Brocks from ANU, who collaborated with Dr Nettersheim on this discovery, suggests that the Protosterol Biota were certainly more intricate and probably larger than bacteria. "We believe they may have been the first predators on Earth, hunting and devouring bacteria," said Professor Brocks.&nbsp;



<h2 id="h-when-protosterol-biota-ruled-the-earth">When Protosterol Biota ruled the Earth</h2>



According to Professor Brocks, the reign of these creatures began around 1.6 billion years ago and lasted until about 800 million years ago. This was a period in Earth's evolutionary timeline that culminated in the "Tonian Transformation." During this significant juncture, more advanced nucleated organisms such as fungi and algae began to prosper.



"The Tonian Transformation is one of the most profound ecological turning points in our planet’s history," said Professor Brocks. "Just as the dinosaurs had to go extinct so that our mammal ancestors could become large and abundant, perhaps the Protosterol Biota had to disappear a billion years earlier to make space for modern eukaryotes."



<h2 id="h-how-the-research-team-made-this-discovery">How the research team made this discovery</h2>



The scientists made this groundbreaking discovery by studying fossil fat molecules tucked away inside a 1.6-billion-year-old rock that had formed at the bottom of the ocean near present-day Australia’s Northern Territory. These molecules, with a primordial chemical structure, suggested the presence of early complex creatures that evolved before LECA and had since vanished.



"Without these molecules, we would never have known that the Protosterol Biota existed. Early oceans largely appeared to be a bacterial world, but our new discovery shows that this probably wasn’t the case," said Dr. Nettersheim.



These fossil molecules have been overlooked for decades, as they did not fit the typical molecular search parameters used by scientists.&nbsp;



"Scientists had overlooked these molecules for four decades because they do not conform to typical molecular search images," said Professor Brocks. "But once we knew what we were looking for, we discovered that dozens of other rocks, taken from billion-year-old waterways across the world, were also oozing with similar fossil molecules."



Dr Nettersheim, who undertook this analysis as a part of his PhD at ANU before moving to the University of Bremen, was not alone in this endeavor. This seminal work involved a multinational collaboration that brought together scientists from Australia, France, Germany, and the United States.



This remarkable discovery of the Protosterol Biota, revealing an unknown chapter of Earth's evolutionary narrative, is a testament to the boundless scope of scientific exploration.&nbsp;



As we delve deeper into the mysteries of the past, we gain valuable insights that help shape our understanding of the present and foresee the trajectory of life's future evolution. The story of our ancient ancestors might be far from complete, but this discovery serves as a fascinating new piece of the puzzle.



<h2 id="h-more-about-the-earliest-life-on-earth">More about the earliest life on Earth</h2>



Life on Earth started at least 3.5 billion years ago, as evidenced by the discovery of fossils of microscopic organisms in rocks of that age.&nbsp;



The very first lifeforms were likely simple, single-celled organisms, analogous to bacteria. This era, known as the Archean Eon, was characterized by a lack of oxygen in the Earth's atmosphere and high levels of volcanic activity.



<h3 id="h-prokaryotes-were-probably-first">Prokaryotes were probably first</h3>



Among the earliest forms of life were prokaryotes. These are simple, single-celled organisms that lack a nucleus or other membrane-bound organelles. The prokaryotes include bacteria and archaea, two domains of life that are still present today.&nbsp;



Many prokaryotes are extremophiles, capable of surviving in harsh environments such as hydrothermal vents and acidic springs, which were common during Earth's early history.



<h3 id="h-significant-leap-forward-when-eukaryotes-arrived">Significant leap forward when eukaryotes arrived</h3>



Life remained microscopic and single-celled for billions of years, a time span known as the Precambrian. Then, around 2.1 billion years ago, a significant evolutionary leap occurred: the emergence of eukaryotes.&nbsp;



These are organisms with complex cells that have a nucleus and other membrane-bound organelles. The first eukaryotes were likely single-celled, like their prokaryotic predecessors, but they represented a significant increase in biological complexity.



<h3 id="h-photosynthesis-changes-everything">Photosynthesis changes everything</h3>



The invention of photosynthesis by cyanobacteria, a type of prokaryote, transformed the Earth's atmosphere by filling it with oxygen. This event, known as the Great Oxygenation Event, occurred around 2.45 billion years ago. The rise of oxygen levels in the atmosphere allowed for the evolution of more complex, multicellular organisms.



Around 600 million years ago, during the Ediacaran Period, the first multicellular animals appeared. These strange creatures bore little resemblance to modern animals, and many of them belonged to groups that have since gone extinct.&nbsp;



<h3 id="h-cambrian-explosion">Cambrian explosion&nbsp;</h3>



It wasn't until the Cambrian explosion, about 540 million years ago, that the ancestors of most modern animal groups emerged. This event was characterized by a rapid increase in biodiversity and complexity.



So, the journey of life on Earth began with simple, single-celled organisms and, over billions of years, evolved into the complex web of biodiversity we see today. This ongoing process of evolution continues to shape life on our planet.



Image Credit: Orchestrated in MidJourney by TA 2023



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Organisms called Protosterol Biota lived 1.6 billion years ago

Diving deep into the realm of life's origin, scientists have...

In an unexpected revelation from <a href="https://www.auburn.edu/">Auburn University</a>'s Department of Biological Sciences, honeybee colonies have demonstrated incredible adaptability and resilience in maintaining their nest structures, even amid severe disturbances. This discovery is in stark contrast to prior beliefs and paves the way for new understanding of these complex creatures.



The study at hand, led by an international team of researchers, centered on the honey bee colonies' intricate, three-dimensional nest-building behavior.&nbsp;



<h2 id="h-how-the-study-was-conducted">How the study was conducted</h2>



The scientists went beyond typical observation methods, employing photo-based, non-destructive techniques. This involved using moveable wooden bee-frames, which allowed for continuous monitoring and analysis of the nests' growth and organization without causing harm to the colonies.



Interestingly, honeybees rapidly construct a well-connected, spherical nest made up of parallel combs. These combs extend uniformly in all directions from the point of origin. But how essential is this seemingly stereotyped structure to the colony's development and functioning?



In an attempt to find an answer, the researchers shook things up. They randomly rearranged the moveable frames in a group of colonies every week, creating a continuous disruption to the nest structure. The initial hypothesis was that such disturbances would inevitably lead to a decrease in colony-level performance.



<h2 id="h-digging-deeper-for-answers">Digging deeper for answers</h2>



But reality was different. There were no significant disparities in worker population, comb area, hive weight, or nest temperature between colonies with disrupted nest structures and those maintaining their original arrangements. This surprising outcome made the researchers dig deeper into how honeybees can compensate for repeated disruptions.



"Sometimes you just have to do the experiment and see what the bees will do," said study senior author Michael L. Smith.



What they found was fascinating. Upon modeling the colony’s building behavior, they discovered that honeybee colonies prioritize structural connectedness when expanding their nests.&nbsp;



Even after significant disruptions, the bees actively repair connections in the nest structure, highlighting their adaptability to alter the comb shape according to the available space within a cavity. This attribute is crucial for survival in the wild, where cavities are not always regular.



<h2 id="h-what-the-researchers-learned">What the researchers learned</h2>



Why do <a href="https://www.earth.com/news/honeybees-create-mental-maps-to-find-their-way-home/">honeybees</a> emphasize nest connectedness? The researchers postulate several reasons. A well-connected nest minimizes the surface area-to-volume ratio, potentially enhancing thermoregulation efficiency, which could lead to better larvae development and winter survival.&nbsp;



Also, a connected structure could facilitate better information sharing among colony members and optimize travel distances within the nest for essential activities, including foraging, feeding larvae, and laying eggs.



"We were all surprised that the shuffled colonies performed as well as they did," said study first author Peter R. Marting. "We expected some shuffled colonies wouldn't even survive the summer. The bees’ resilience led us to take a closer look at how and where exactly workers were adding new comb to shape their nests and ultimately led us to develop the predictive comb growth models."



This study is a step towards understanding the mechanisms behind the adaptive building strategies of these social insects. The researchers believe that insights into such resilience in complex systems could have implications beyond the realm of entomology.



The findings have been published in the journal <a href="http://dx.doi.org/10.1098/rspb.2022.2565">Proceedings of the Royal Society B: Biological Sciences</a> and are available for reference.



<h2 id="h-more-about-honeybees">More about honeybees</h2>



Honeybees play a crucial role in ecosystems as key pollinators. They help fertilize flowers by transferring pollen from the male parts of a flower to the female parts.&nbsp;



This fertilization process allows plants to fruit and seed, leading to the production of a vast majority of our fruits, nuts, and vegetables. It's not an exaggeration to say that without honeybees, our food system would be severely compromised.



The role of honeybees isn't just confined to agricultural landscapes. They also contribute significantly to the pollination of wild plants, thereby maintaining biodiversity and the robustness of natural habitats. The services provided by these insects underpin much of the terrestrial ecosystems and their robust functioning.



<h3 id="h-facing-various-threats-from-climate-change">Facing various threats from climate change</h3>



However, honeybees and other pollinators worldwide are facing numerous threats, one of which is climate change. Changes in climate patterns can disrupt the synchronized timing between bees and flowering plants.&nbsp;



If flowers bloom earlier or later due to unusual weather patterns, bees may miss the window for foraging. This could lead to a decrease in the availability of their food sources, subsequently impacting their survival and reproduction rates.



Moreover, extreme weather events linked to climate change, such as excessive heat, cold, drought, or heavy rains, can directly affect bee health and survival. For instance, bees can overheat and die during heatwaves or become inactive during cold snaps, leading to a decline in their populations. Severe weather conditions can also damage or destroy hives.



Increasing temperatures also alter geographical ranges for some species, potentially leading to the loss of suitable habitats for bees. Rising temperatures might enable the spread of pathogens and pests into new areas, posing further threats to bees.



<h3 id="h-pesticides-diseases-and-other-challenges-to-honeybees">Pesticides, diseases and other challenges to honeybees</h3>



In the context of honeybee populations, climate change can exacerbate the challenges they are already facing, such as exposure to pesticides, habitat loss due to agriculture and urbanization, and diseases and pests. All these factors together contribute to the worrying decline in honeybee populations observed in recent years.



Protecting and promoting the health of honeybees is not only important for preserving biodiversity but also crucial for our food security. Hence, there is a pressing need for conservation efforts, sustainable agricultural practices, and proactive measures to mitigate climate change for the survival of these invaluable insects and, in turn, the health of our ecosystems.



—-



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Honeybees have surprising abilities to maintain their nest structure

In an unexpected revelation from Auburn University's Department of Biological...

Sleep is a universal experience that encompasses complex biological functions. For us humans, it is divided into different phases – rapid eye movement (REM) and non-REM sleep. These sleep phases have unique associations with our physiology, brain activity, and cognition.&nbsp;



During REM <a href="https://www.earth.com/news/exercise-counteracts-negative-effects-of-sleep-deprivation/">sleep</a>, our brain activity peaks and ushers in vivid, peculiar, and emotional dreams. Meanwhile, non-REM sleep, a time of metabolic slowdown, enables the brain to flush out waste products. This cleaning mechanism plays a vital role in preventing neurological disorders like Alzheimer's disease.



Despite the clarity in understanding human sleep, the question of whether birds undergo similar processes during sleep has been a mystery. However, new research led by Professor Onur Güntürkün, head of the Biopsychology Department at <a href="http://www.ruhr-uni-bochum.de/en">Ruhr University Bochum</a>, has recently uncovered fascinating insights into avian sleep patterns.



<h2 id="h-what-is-happening-in-pigeon-brains-while-they-sleep">What is happening in pigeon brains while they sleep?</h2>



"Birds and mammals share a common evolutionary ancestor dating back about 315 million years, yet their sleep patterns, including both REM and non-REM phases, are remarkably alike," said Güntürkün.



In order to further investigate the intricacies of bird sleep, the research team combined cutting-edge technologies, namely infrared video cameras and functional magnetic resonance imaging (fMRI). They trained 15 pigeons to sleep under these experimental conditions, and closely observed their sleeping and wakeful states.



The video recordings revealed interesting details about avian sleep. "We observed whether one or both eyes were open or closed, tracked eye movements and changes in pupil size through the transparent eyelids of the pigeons during sleep," explained Mehdi Behroozi, a member of the Bochum team.



Simultaneously, the fMRI recordings delivered insights about brain activation and cerebral spinal fluid flow in the ventricles.



<h2 id="h-do-pigeons-dream-of-flying">Do pigeons dream of flying?</h2>



"During REM sleep, we observed strong activity in brain regions responsible for visual processing, including those areas analyzing the movement of a pigeon's surroundings during flight," said Behroozi. In addition, areas processing signals from the body, especially the wings, were also active.



Based on these observations, Behroozi suggests that birds may dream during REM sleep, possibly even reliving their flight experiences in their dreams.



Another intriguing finding was the activation of the amygdala during REM sleep. This implies that birds, like humans, may experience emotional content in their dreams.



"Pigeons’ dreams might include emotions as well," said Gianina Ungurean from the Avian Sleep Group at the Max Planck Institute for Biological Intelligence. This theory is further supported by the birds' rapid pupil contraction during REM sleep, similar to their reactions during courtship or aggressive behaviors.



<h2 id="h-how-rem-sleep-helps-birds">How REM sleep helps birds</h2>



Just like in humans, non-REM sleep in pigeons is a period of enhanced cerebral spinal fluid flow through ventricles. However, a ground-breaking discovery was made: for the first time in any species, the researchers found that this fluid flow diminished significantly during REM sleep.



Niels Rattenborg, head of the Avian Sleep Group, explained this phenomenon: "The increased influx of blood into the brain during REM sleep, which supports the heightened brain activity, might obstruct the cerebral spinal fluid from moving from the ventricles into the brain. This implies that REM sleep and its functions might come at the cost of waste removal from the brain."



Despite this, the team is contemplating that REM sleep might aid in waste removal in unexpected ways. "The surge of blood at the onset of REM sleep increases vessel diameter. This could push cerebral spinal fluid that entered the space during non-REM sleep into the brain tissue, promoting outflow of waste-laden fluids," said Ungurean.



This cleaning process might be particularly critical for birds due to their higher neuronal density compared to mammals. As such, they might need more efficient, or more frequent flushing cycles to remove waste products.&nbsp;



Birds' sleep consists of more, but shorter REM phases compared to mammals. The frequent surges of blood associated with these REM phases might be instrumental in keeping their densely packed brains free of harmful waste products.



<h2 id="h-what-the-future-holds-for-bird-sleep-research">What the future holds for bird sleep research</h2>



The experts are enthusiastic about future research possibilities. They plan to delve further into the potential role of REM sleep in waste removal. Additionally, they hope to decode the content of a pigeon’s dream.



"We hope to train birds to report if and what they just saw upon awakening from REM sleep. That would be a crucial step towards confirming whether they dream," said Ungurean.



Without the detailed analysis of bird dreams, these new findings already enhance our understanding of sleep's role in birds and humans. The research, published in the journal <a href="http://dx.doi.org/10.1038/s41467-023-38669-1">Nature Communications</a>, underscores the significance of sleep in sustaining a healthy brain and averting cognitive decline. It also suggests that dreaming, this peculiar yet universal phenomenon, has a deeply-rooted evolutionary history.



<h2 id="h-more-about-rem-sleep">More about REM sleep</h2>



Rapid Eye Movement (REM) sleep is one of the five stages of the human sleep cycle, named for the characteristic rapid movement of the eyes that occurs during this phase. REM sleep is distinct from the four stages of non-REM sleep, characterized by unique physiological, neurological, and psychological features.



<h3 id="h-physiologically">Physiologically</h3>



REM sleep is fascinating. While the brain shows activity levels similar to wakefulness, most of the body's voluntary muscles are paralyzed. This phenomenon, known as REM atonia, is believed to be a protective mechanism that prevents us from acting out our dreams. Heart rate and blood pressure tend to fluctuate, and breathing can become irregular.



<h3 id="h-neurologically">Neurologically</h3>



REM sleep is a period of high brain activity. Brain waves during this stage resemble those during wakefulness, which is why REM sleep is sometimes referred to as paradoxical sleep. Several neurotransmitters play pivotal roles in modulating REM sleep, including acetylcholine, which is particularly active, and monoamines (serotonin, norepinephrine, and histamine), which are almost completely inactive.



<h3 id="h-psychologically">Psychologically&nbsp;</h3>



REM sleep is the stage when the most vivid dreaming occurs. This is thought to be related to the high brain activity and the function of certain brain regions during REM sleep. The exact purpose of dreams is still a topic of ongoing scientific debate, but theories suggest they may help with processing emotions, consolidating memory, and learning.



Additionally, REM sleep is believed to play a crucial role in brain development. Infants, for instance, spend much of their sleep time in the REM phase. It's also during REM sleep that proteins are synthesized, contributing to brain repair and growth.



Though it's known that REM sleep is important, as evidenced by its conservation across many animal species and the negative health impacts linked to its deprivation, many aspects of REM sleep remain a mystery. Sleep, in general, is an active area of research as scientists continue to unveil its many complexities.



<h2 id="h-more-about-dreaming">More about dreaming&nbsp;</h2>



Dreaming is a fascinating and complex phenomenon that occurs during sleep, particularly during the Rapid Eye Movement (REM) phase, but also during certain stages of non-REM sleep. While we often associate dreams with vivid visual or auditory experiences, dreams can involve any of the senses and a wide range of emotions. Dream content can range from mundane daily activities to bizarre or surreal scenarios.



While everyone dreams, not everyone recalls their dreams. The ability to remember dreams varies greatly among individuals and can be influenced by a variety of factors including sleep stages, interruptions in sleep, stress, and certain lifestyle factors. Some people remember multiple dreams per night, while others recall their dreams infrequently.



There are many theories about why we dream, and understanding the purpose of dreams has been a subject of debate in the scientific and philosophical community for thousands of years. Here are a few key theories:



<h3 id="h-emotional-processing">Emotional processing&nbsp;</h3>



Some believe dreams are a way for the brain to process emotions and experiences from the day. This might explain why certain events or feelings from waking life often recur in dreams.



<h3 id="h-memory-consolidation">Memory consolidation</h3>



Another theory proposes that dreams play a role in consolidating and processing information gathered during the day, integrating it into long-term memory.



<h3 id="h-problem-solving">Problem-solving</h3>



Some theories suggest that dreams are a space where the brain can work on solving problems encountered during waking hours, without the constraints of reality.



<h3 id="h-neural-pathway-stimulation">Neural pathway stimulation</h3>



Dreams might serve as a means for the brain to stimulate and develop neural connections, especially during infancy and early childhood when brain development is most active.



<h3 id="h-psychodynamic-freudian-interpretation">Psychodynamic (Freudian) interpretation</h3>



Psychoanalyst Sigmund Freud posited that dreams are a reflection of repressed desires and unconscious thoughts. While this theory has been influential, it is not widely accepted in contemporary neuroscience.



It's important to note that while these theories offer different perspectives, they're not mutually exclusive, and the true purpose of dreams may encompass elements from each theory or be something yet undiscovered.



A relatively new field of research, dream science, employs various technologies such as electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) to better understand the neurological underpinnings of dreaming.&nbsp;



Despite advancements in this area, much about the nature and purpose of dreams remains enigmatic and continues to captivate both scientists and the general public.



The study represents the collective efforts of various researchers including the Bochum Biopsychology team, the Max Planck Institute for Biological Intelligence, the Max Planck Institute for Neurobiology of Behaviour, the Neurophysiology Department at Ruhr University Bochum, and the Université Claude Bernard Lyon. This cross-institution collaboration adds further robustness and breadth to these intriguing insights into avian sleep processes.



—-



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Do birds dream of flying? Scientists say they now know the answer

Sleep is a universal experience that encompasses complex biological functions....

The time has come to discuss a pressing issue in the realm of winter sports: the environmental impact of artificial snow production.&nbsp;



The first-ever national study exploring this topic has revealed that the process of developing artificial snow places a significant strain on our climate. Specifically, the <a href="https://www.earth.com/news/how-much-energy-do-plants-use-to-lift-water-from-the-soil/">energy</a> needed to produce snow for yearly ski operations in Canada alone equals that consumed by nearly 17,000 households annually.



This study, which is the first of its kind, was conducted by experts from the <a href="https://uwaterloo.ca/">University of Waterloo</a>, Canada, and the University of Innsbruck, Austria.&nbsp;



<h2 id="h-the-cost-now-vs-the-future-cost">The cost now vs. the future cost</h2>



Published in the journal <a href="http://dx.doi.org/10.1080/13683500.2023.2214358">Current Issues in Tourism</a>, the research has revealed that the creation of an estimated 42 million cubic meters of machine-made snow in an average Canadian winter requires 130,095 tons CO2e. This level of carbon dioxide is comparable to what 155,141 acres of forest would sequester in one year.



The challenge is set to escalate as climate change advances. Future requirements for snowmaking will increase, leading to a surge in water and energy demands. This rise will occur even as average ski seasons continue to shorten in the coming decades.



As the researchers point out, a comprehensive solution to this problem requires cooperation. Ski operators, policymakers, environmental organizations, and even skiers themselves need to join forces. They should work together to establish and support policies and practices that "prioritize sustainability in addressing the challenges posed by climate change and its associated impacts on snowpack."



<h2 id="h-rules-and-regulations-adopting-a-systems-approach">Rules and regulations - adopting a systems approach</h2>



Professor Daniel Scott, co-author of the study, emphasized this point: “Our results underscore the need to adopt a systems approach to ensure the long-term sustainability of ski tourism.”



He suggested that part of this approach should involve "embracing innovation and investing in energy-efficient snowmaking technologies, promoting water conservation measures, and accelerating the transition to renewable energy sources."&nbsp;



“Snowmaking can actually help reduce total emissions from tourism when it enables millions of skiers to ski regionally instead of driving or flying to far off ski resorts or selecting another type of carbon intense holiday. Net-zero compatible ski holidays are already possible in destinations like Quebec and our study shows a vibrant and resilient future for ski tourism is possible," said Professor Scott.



Canada is home to 237 ski areas that play a vital role in the country's tourism sector. These areas see an average of 18.2 million skier visits annually, including 2.7 million international visits.



However, these statistics come with some implications. Current electrical grid carbon intensity shows that Canadian snowmaking uses approximately 478,000 megawatt-hours (MWh) of electricity each year. This usage results in 130,095 tons of associated CO2 emissions and requires an estimated 43.4 million cubic meters of water to produce over 42 million cubic meters of artificial snow.



<h2 id="h-as-climate-warms-so-do-environmental-demands-of-snowmaking">As climate warms, so do environmental demands of snowmaking</h2>



With climate change having an increasing impact on the snowpack in ski areas worldwide, ski operators are increasingly leaning on snowmaking to maintain ski seasons and ensure visitor satisfaction. By 2050, the study estimates snowmaking requirements in Canada will jump between 55% and 97%, with water and energy requirements increasing proportionally.



But there's a glimmer of hope on the horizon. Canada is beginning to enact much-needed decarbonization policies that could significantly decrease ski operations-related emissions.&nbsp;



Professor Scott expressed optimism, saying that “snowmaking emissions are expected to decline substantially, thanks to the ongoing efforts to decarbonize provincial electricity grids in alignment with current policy targets."



To maintain a sustainable future for ski tourism, reassessment of emissions and water use will be necessary as climate change advances and decarbonization targets are pursued. In conclusion, this study offers an important first look at the environmental impacts of snowmaking and its potential for sustainable development.&nbsp;



<h2 id="h-mysteries-still-remain-questions-left-unanswered">Mysteries still remain, questions left unanswered</h2>



However, there is still work to be done in this field. The researchers emphasize that while their study provides a vital foundation for understanding the impacts of snowmaking, it represents only the first step in what should be an ongoing examination of this issue.



Artificial snow production's future sustainability will also need to be re-evaluated in conjunction with destination-level sustainable development strategies. As efforts to decarbonize continue and climate change progresses, the relationships between emissions, water use, and ski resort operation will undoubtedly evolve. Monitoring these changes and adjusting practices accordingly will be vital to preserving ski tourism's long-term viability.



It's important to remember that the world of winter tourism isn't limited to just Canada. Globally, many countries have thriving ski industries that are grappling with similar issues. The findings of this study, while specific to Canada, offer insights that could be valuable to ski areas worldwide.



In other parts of the world where snowmaking is employed, such as in Europe or the United States, there may be similar or even higher levels of emissions and water usage. That's why this study serves as a wake-up call for those in the ski industry globally to take action.



<h2 id="h-global-ski-industry-must-join-together-and-innovate">Global ski industry must join together and innovate</h2>



The findings lay bare a vital truth: the ski industry, like all sectors, has a part to play in the global effort to combat climate change. There is a need for more investment in renewable energy sources, energy-efficient snowmaking technologies, and water conservation measures.



Ultimately, the challenge of sustainable snowmaking is one piece of a much larger puzzle. Addressing climate change will require systemic changes across multiple sectors and scales, from local businesses to international policy. In the fight against climate change, every effort counts – and in the case of ski resorts, it could mean the difference between flourishing winter tourism and empty slopes.



To end on Professor Scott's optimistic note, let us remember that “a vibrant and resilient future for ski tourism is possible." As we navigate the challenges ahead, his words remind us that through innovation, collaboration, and commitment to sustainability, we can continue to enjoy our beloved winter pastimes while protecting the planet for future generations.



<h2 id="h-more-about-artificial-snowmaking">More about artificial snowmaking</h2>



Artificial snowmaking is a process used primarily in the ski industry to supplement natural snowfall and ensure that ski resorts can operate consistently throughout the season. Here are the main aspects of artificial snowmaking that you might find interesting:



<h3 id="h-process-of-snowmaking">Process of snowmaking</h3>



Snowmaking involves spraying a mist of water and pressurized air from snow cannons or snow guns. The cold outdoor air causes the water droplets to freeze into snow as they fall to the ground. The key to this process is that the water must be atomized - broken up into tiny droplets - to ensure that the water can freeze quickly and completely before it lands.



<h3 id="h-temperature-requirements">Temperature requirements</h3>



For snowmaking to be effective, the weather conditions need to be right, particularly in terms of temperature and humidity. While the specific conditions can vary, generally the temperature should be below freezing (0°C/32°F), and lower temperatures can improve the efficiency of snowmaking. However, snow can still be made at temperatures slightly above freezing if the humidity is low enough, a factor represented by the concept of "wet-bulb temperature."



<h3 id="h-equipment">Equipment&nbsp;</h3>



The primary pieces of equipment used in snowmaking are snow cannons or snow guns, water pumps, air compressors, and a network of pipes to deliver water and compressed air to the snow guns. Snow guns come in various designs, with fan guns and lance-style guns being common types.



<h3 id="h-environmental-impact">Environmental impact</h3>



Artificial snowmaking is energy-intensive and requires significant amounts of water, which can place a strain on local resources. Furthermore, depending on the source of the electricity used in the process, it can contribute to greenhouse gas emissions.&nbsp;



As a result, there is ongoing research into ways to make the process more sustainable, such as by improving the energy efficiency of snowmaking equipment and using renewable energy sources.



<h3 id="h-use-in-ski-industry">Use in ski industry&nbsp;</h3>



Ski resorts often rely on artificial snow to open earlier in the season, stay open later, and provide a more predictable and consistent skiing surface. In many regions, climate change is causing winters to be warmer and less predictable, which has increased the reliance on snowmaking.



<h3 id="h-other-uses">Other Uses</h3>



Beyond the ski industry, artificial snow is sometimes used for other purposes, such as in film or TV productions, for winter events in regions where snow doesn't naturally occur, or for scientific research and testing.



It's worth noting that despite its benefits in ensuring a consistent skiing surface, artificial snow does have differences compared to natural snow. It's typically denser and more durable, which can affect skiing conditions.



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Artificial snowmaking: Sustainability must become a priority

The time has come to discuss a pressing issue in...

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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

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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

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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

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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

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&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.

Kainji Lake in north central Nigeria

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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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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.

Designing crops that can beat the heat

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The glowing remains of a massive star Today&#8217;s Image of the Day from <a href="https://www.nasa.gov/">NASA</a> features a striking view of the Cygnus Loop nebula, which is a large supernova remnant (SNR) in the constellation Cygnus. The glowing remains of a massive star
The nebula, which is located about 1,500 light-years from our planet, was formed during the explosive death of a massive star about 10,000 &#8211; 20,000 years ago.
Hot dust and gas can be seen glowing brightly in this ultraviolet image captured by NASA&#8217;s Galaxy Evolution Explorer. A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way. 
There are two common routes to a supernova: either a massive star may run out of fuel, ceasing to generate fusion energy in its core, and collapsing inward under the force of its own gravity to form a neutron star or a black hole; or a white dwarf star may accrete material from a companion star until it reaches a critical mass and undergoes a thermonuclear explosion. In either case, the resulting supernova explosion expels much or all of the stellar material with velocities as much as 10% the speed of light (or approximately 30,000 km/s). These speeds are highly supersonic, so a strong shock wave forms ahead of the ejecta. That heats the upstream <a href="https://www.earth.com/news/plasma-rain-sun/">plasma</a> up to temperatures well above millions of K. The shock continuously slows down over time as it sweeps up the ambient medium, but it can expand over hundreds or thousands of years and over tens of parsecs before its speed falls below the local sound speed. 
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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
Image Credit: NASA

The glowing remains of a massive star

The Columbia Glacier in southern Alaska. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Columbia Glacier in southern Alaska, which has experienced a long period of rapid retreat followed by a more stable period in recent years. 
Shad O’Neel is a glaciologist at the USGS Alaska Science Center who has been observing the behavior of the Columbia Glacier for many years. 

"The total loss of ice is down substantially,” said O’Neel. “But there is still impressive retreat.”

The glacier has lost more than half of its total thickness and volume since the 1980s. 

This natural color image was captured on June 21, 2019 by the Operational Land Imager on Landsat 8.

--Southeast Alaska, colloquially referred to as the Alaska Panhandle or Alaskan Panhandle, is the southeastern portion of the <a title="U.S. state" href="https://en.wikipedia.org/wiki/U.S._state">U.S. state</a> of <a title="Alaska" href="https://en.wikipedia.org/wiki/Alaska">Alaska</a>, bordered to the east by the northern half of the <a title="Provinces and territories of Canada" href="https://en.wikipedia.org/wiki/Provinces_and_territories_of_Canada">Canadian province</a> of <a title="British Columbia" href="https://en.wikipedia.org/wiki/British_Columbia">British Columbia</a>. The majority of Southeast Alaska's area is part of the <a title="Tongass National Forest" href="https://en.wikipedia.org/wiki/Tongass_National_Forest">Tongass National Forest</a>, the United States' largest <a class="mw-redirect" title="United States National Forest" href="https://en.wikipedia.org/wiki/United_States_National_Forest">national forest</a>. In many places, the <a class="mw-redirect" title="International border" href="https://en.wikipedia.org/wiki/International_border">international border</a> runs along the crest of the <a title="Boundary Ranges" href="https://en.wikipedia.org/wiki/Boundary_Ranges">Boundary Ranges</a> of the <a title="Coast Mountains" href="https://en.wikipedia.org/wiki/Coast_Mountains">Coast Mountains</a> (see <a title="Alaska boundary dispute" href="https://en.wikipedia.org/wiki/Alaska_boundary_dispute">Alaska boundary dispute</a>). The region is noted for its scenery and mild, rainy <a title="Climate" href="https://en.wikipedia.org/wiki/Climate">climate</a>.

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory

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