<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features a wall of dust moving across the Korean Peninsula on April 25, 2024.</p>



<p>As the Northern Hemisphere ushers in the warmth of spring, East Asia grapples with a less welcome sign of the season: colossal <a href="https://www.earth.com/news/dust-storms-in-the-gulf-of-alaska-help-shape-the-global-climate/" target="_blank" rel="noreferrer noopener">dust storms</a>. </p>



<h2 class="wp-block-heading" id="h-desert-dust-reaches-the-korean-peninsula-nbsp">Desert dust reaches the Korean Peninsula&nbsp;</h2>



<p>Originating from the expansive Gobi and Taklamakan deserts, these dust plumes journey across China, reaching as far as the Korean Peninsula and southern Japan, reshaping the springtime landscape both literally and metaphorically.</p>



<p>The phenomenon was starkly illustrated on April 25, 2024, when NASA's Aqua satellite, equipped with the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor, captured a dramatic image of a massive dust wall traversing the Korean Peninsula.&nbsp;</p>



<h2 class="wp-block-heading" id="h-primary-source-of-the-dust-over-korea">Primary source of the dust over Korea</h2>



<p>The imagery from the preceding day, courtesy of South Korea’s GEO-KOMPSAT-2A satellite and NASA’s Terra and Aqua satellites, pinpointed the Gobi Desert in Inner Mongolia as the primary source of this <a href="https://www.earth.com/news/atmospheric-dust-plays-surprisingly-crucial-role-in-stabilizing-ocean-ecosystems/" target="_blank" rel="noreferrer noopener">dust</a>. </p>



<p>Compounding the environmental spectacle, a phytoplankton bloom, partially veiled by the dust, was visible to the east of the Korean Peninsula, presenting a complex interaction of earth and ocean.</p>



<h2 class="wp-block-heading" id="h-where-does-the-dust-go">Where does the dust go?</h2>



<p>This seasonal dust does not simply settle locally but sometimes ascends high into the atmosphere, occasionally soaring above cloud level. This elevation enables the particles to traverse vast distances, including crossing the Pacific Ocean to North America.&nbsp;</p>



<p>However, not all the <a href="https://www.earth.com/news/sahara-desert-dust-storms-carry-harmful-bacteria-and-fungi-around-the-globe/" target="_blank" rel="noreferrer noopener">dust</a> achieves such heights; much remains nearer to the ground, significantly deteriorating air quality in one of the planet's most densely populated areas.</p>



<p>The health implications of these dust storms are profound. Breathing in the fine particulate matter, particularly PM2.5, is linked to severe cardiovascular and respiratory issues.</p>



<h2 class="wp-block-heading" id="h-dust-storms-in-east-asia-nbsp">Dust storms in East Asia&nbsp;</h2>



<p>Dust storms in East Asia are commonly known as yellow dust, Asian dust, yellow wind, or China dust storms. The storms are typically most frequent in spring and can extend into early summer. They arise when strong winds lift large amounts of sand and dust from deserts in China and Mongolia, then transport these particles across the region.</p>



<p>The key factors contributing to these dust storms include:</p>



<h3 class="wp-block-heading" id="h-natural-conditions">Natural conditions</h3>



<p>The Gobi Desert and other arid regions in China and Mongolia are the primary sources of the dust. The natural aridness and loose soil make these areas prone to dust lift-off under certain meteorological conditions.</p>



<h3 class="wp-block-heading" id="h-meteorological-factors">Meteorological factors</h3>



<p>Spring brings about changes in temperature and pressure, which can result in strong winds. These winds are capable of carrying dust over long distances. The occurrence and intensity of these storms are closely linked to weather patterns such as the strength of the Siberian High and the East Asian jet stream.</p>



<h3 class="wp-block-heading" id="h-human-impact">Human impact</h3>



<p>Overgrazing, <a href="https://www.earth.com/news/global-deforestation-crisis-how-can-we-stop-massive-forest-losses/" target="_blank" rel="noreferrer noopener">deforestation</a>, and land degradation have exacerbated the frequency and intensity of dust storms. Human activities have led to increased desertification, which contributes to the severity of the storms.</p>



<p>Efforts to combat these dust storms have included afforestation projects, such as planting trees to stabilize the soil, and sustainable land management practices aimed at reducing <a href="https://www.earth.com/news/oases-grow-by-human-effort-but-face-threats-from-desertification/" target="_blank" rel="noreferrer noopener">desertification</a>. Regional cooperation among affected countries has also been essential in monitoring and managing the impacts of these dust events.</p>



<h2 class="wp-block-heading" id="h-more-about-the-korean-peninsula-nbsp">More about the Korean Peninsula&nbsp;</h2>



<p>The Korean Peninsula extends southward from the eastern end of the Asian continent and is bordered by the Sea of Japan (East Sea) to the east, the Yellow Sea to the west, and the Korea Strait connecting to the East China Sea to the south. It is divided into two distinct sovereign states: North Korea and South Korea.</p>



<h3 class="wp-block-heading" id="h-historical-context">Historical context</h3>



<p>Historically, the Korean Peninsula was unified for much of its history under various kingdoms such as Goguryeo, Silla, Baekje, and later the Goryeo and Joseon dynasties. The last, the Joseon Dynasty, lasted until the early 20th century.&nbsp;</p>



<p>Following the end of World War II in 1945, the peninsula was divided into North and South Korea in 1948 amid growing Cold War tensions, leading to the Korean War from 1950 to 1953, which ended with an armistice but no formal peace treaty.</p>



<h3 class="wp-block-heading" id="h-cultural-aspects-of-north-and-south-korea">Cultural aspects of North and South Korea </h3>



<p>Korean culture is distinguished by its language, customs, and cuisine. Both North and South Korea share cultural foundations based on their Confucian heritage, which influences social etiquette, family relations, and personal conduct. However, decades of separation have fostered distinct societal developments in each country.</p>



<h3 class="wp-block-heading" id="h-economy">Economy</h3>



<p>North Korea has a largely isolated economy with limited engagement with the international community, heavily reliant on its natural resources and some agricultural output.</p>



<p>South Korea boasts the 10th largest economy in the world (as of 2021), with strong industries in electronics, telecommunications, automobile production, shipbuilding, and chemical manufacturing. It is also a leader in technological innovation and infrastructure.</p>



<h3 class="wp-block-heading" id="h-current-issues">Current issues</h3>



<p>The Korean Peninsula continues to face challenges, including security concerns due to North Korea's nuclear ambitions and the ongoing military tensions between the North and South. </p>



<p>Additionally, both countries deal with internal and external economic pressures, global market dynamics, and cultural exportation impacting global perceptions and economic health.</p>



<p>The Korean Peninsula presents a unique study in contrasts, with profound historical ties and shared cultural elements, yet marked differences in political, economic, and social systems.</p>



<p>Image Credit: NASA Earth Observatory&nbsp;</p>



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Massive wall of dust travels over the Korean Peninsula 

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

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features the picturesque wetlands of Spain's Doñana National Park, This vital ecosystem, located in the Andalusia region, has received some long-awaited rainfall after enduring years of severe <a href="https://www.earth.com/news/climate-change-has-made-droughts-20-times-more-likely/" target="_blank" rel="noreferrer noopener">drought</a> conditions. </p>



<p>A significant increase in rainfall in March 2024 brought temporary relief to this UNESCO World Heritage Site and Biosphere Reserve, known for its rich biodiversity and critical role as a Ramsar Wetland of International Importance.</p>



<h2 class="wp-block-heading" id="h-a-decade-of-drought-in-donana-national-park">A decade of drought in Doñana National Park</h2>



<p>For over a decade, Doñana National Park has faced below-average rainfall levels, with the situation worsening significantly in the past three years. These years have recorded some of the lowest annual precipitation totals, compounded by unusually high temperatures across the country.&nbsp;</p>



<p>The effects of <a href="https://www.earth.com/news/drought-to-downpour-climate-change-triggers-extreme-weather-shifts/" target="_blank" rel="noreferrer noopener">climate change</a> were starkly visible in January 2024, which was noted as Spain's warmest January since records began, with temperatures averaging 2.4 degrees Celsius higher than normal.</p>



<p>The first quarter of 2024 continued this trend, potentially marking it as the warmest first quarter since 1961. The prolonged <a href="https://www.earth.com/news/global-drought-crisis-un-warns-of-unprecedented-emergency/" target="_blank" rel="noreferrer noopener">drought</a> has had a devastating impact on the park’s ecosystem, drying up <a href="https://www.earth.com/news/nearly-all-of-the-worlds-salt-marshes-may-be-underwater-by-2100/" target="_blank" rel="noreferrer noopener">marshes</a> and affecting both flora and fauna.</p>



<h2 class="wp-block-heading" id="h-welcome-change-in-the-weather">Welcome change in the weather</h2>



<p>The heavy rains that arrived in late March 2024 have momentarily brought some relief to the region. Satellite images acquired by the OLI on Landsat 8 and the OLI-2 on Landsat 9 showed significant changes in the landscape by April 9, 2024.&nbsp;</p>



<p>The featured image shows that marshes have been replenished and ponds have been temporarily filled, contrasting sharply with the desolate conditions observed just a year earlier.</p>



<p>A weather station in the park recorded 145 millimeters of rainfall in March 2024, making it the second-wettest March on record. Since the start of the water year in September 2023, the area has received over 400 millimeters of rainfall, surpassing the totals of each of the last three full water years. Despite this increase, the precipitation still falls short of the historical yearly average of more than 500 millimeters.</p>



<h2 class="wp-block-heading" id="h-ecological-responses-and-challenges">Ecological responses and challenges</h2>



<p>The western part of the park is home to thousands of small, shallow pools known as Mediterranean temporary ponds, which naturally experience cycles of flooding and drying. Following the recent rains, several of the largest ponds flooded, as did marsh areas farther inland, though some regions remained dry.</p>



<p>The Doñana Biological Station reported that this influx of water led to a resurgence of vegetation beneficial to breeding waterfowl such as coots, grebes, and herons.&nbsp;</p>



<p>However, despite these positive signs, the challenges remain significant. Development pressures from agricultural fields and an adjacent resort town continue to strain the local aquifer, exacerbating the water scarcity and impacting the wetland's ecological balance.</p>



<h2 class="wp-block-heading" id="h-long-term-concerns-for-donana-national-park">Long-term concerns for Doñana National Park</h2>



<p>Javier Bustamante, a researcher at the Doñana Biological Station, emphasized that while the rainfall has eased some of the immediate drought-related issues, it does not address the deeper problem of groundwater overexploitation.&nbsp;</p>



<p>"The rains have partially alleviated the most immediate drought problems, but they do not solve the invisible problem of groundwater overexploitation," Bustamante stated, highlighting the complex nature of the challenges facing Doñana.</p>



<p>The overall effect of the rainfall will become clearer in the coming months, but experts caution that the changes observed might not signify long-term relief. Conservation efforts continue to focus on managing external pressures and restoring the ecological balance to preserve Doñana National Park for future generations.</p>



<h2 class="wp-block-heading" id="h-more-about-donana-national-park">More about Doñana National Park</h2>



<p>Doñana National Park is one of Europe's most important and diverse natural reserves. This vast park stretches across parts of the provinces of Huelva, Seville, and Cádiz. It was established as a national park in 1969 and covers an area of approximately 543 square kilometers.</p>



<p>The park is celebrated for its extraordinary biodiversity. It serves as a critical stopover, breeding, and wintering site for thousands of European and African migratory birds.&nbsp;</p>



<p>Doñana's complex ecosystem includes <a href="https://www.earth.com/news/coastal-wetlands-are-inching-closer-to-extinction-as-the-world-heats-up/" target="_blank" rel="noreferrer noopener">marshlands</a>, shallow streams, and sand dunes, providing habitat for a wide variety of plant and animal species. Among its notable inhabitants are the Iberian lynx and the Spanish imperial eagle, both of which are endangered species.</p>



<p>Doñana also has a rich cultural heritage; it has been influenced by various civilizations throughout history, including the Romans and Moors. This history is reflected in the archaeological sites found within its boundaries, including the remains of the town of La Algaida.</p>



<p>Image Credit: NASA Earth Observatory&nbsp;</p>



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Doñana National Park gets temporary relief from drought

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features Ruang, a small volcanic island in North Sulawesi, Indonesia. The tranquil environment of Ruang was shattered by a powerful volcanic eruption on the night of April 16, 2024.</p>



<p>This event has left the island's 800 residents grappling with its devastating aftermath, while scientists are assessing its potential global effects.</p>



<h2 class="wp-block-heading" id="h-a-violent-awakening-on-ruang">A violent awakening on Ruang</h2>



<p>Ruang, located in the Sangihe Islands arc, is known for its long history of <a href="https://www.earth.com/news/volcanic-eruptions-play-an-overlooked-role-in-earths-climate/" target="_blank" rel="noreferrer noopener">volcanic activity</a>, but the intensity of the latest eruption has been particularly alarming. The <a href="https://www.earth.com/news/explosive-volcanic-eruption-triggered-an-hours-long-thunderstorm/" target="_blank" rel="noreferrer noopener">eruption</a> produced explosive discharges, sending vast plumes of ash and gas soaring into the stratosphere. The force of nature transformed lush greenery into a gray wasteland.</p>



<p>“Late on April 16, 2024, the mountain roared to life, unleashing a series of explosive eruptions that, at times, sent plumes of ash and gas billowing high into the stratosphere. The eruption also bombarded the island with tephra, small pebbles of lapilli, and fine shards of pulverized rock called ash,” said NASA.</p>



<h2 class="wp-block-heading" id="h-extensive-damage-and-humanitarian-efforts">Extensive damage and humanitarian efforts</h2>



<p>The eruption's immediate impact was severe, with settlements on the north side of Ruang and Laingpatehi village experiencing extensive damage due to volcanic debris.&nbsp;</p>



<p>More than 500 houses were destroyed or severely damaged, according to Indonesia’s disaster management agency, Badan Nasional Penanggulangan Bencana (BNPB). The heavy ashfall also impacted local agriculture, damaging crops and farms.&nbsp;</p>



<p>In response to the crisis, the Sam Ratulangi International Airport in nearby Manado was temporarily closed, disrupting travel and causing widespread flight cancellations. It was not until April 22 that the airport could reopen, following significant cleanup efforts and a decrease in the volcanic threat level.</p>



<h2 class="wp-block-heading" id="h-scientific-analysis-and-global-concerns">Scientific analysis and global concerns</h2>



<p>The eruption has attracted significant scientific interest due to the vast quantities of ash and sulfur dioxide it emitted. Atmospheric scientist Ghassan Taha from NASA’s Goddard Space Flight Center noted, "We expect to see aerosol particles circulating in the stratosphere for weeks, if not months." This observation is critical as particles reaching this altitude can have extensive, albeit temporary, effects on global climate patterns.</p>



<p>Volcanologist Simon Carn from Michigan Technological University reported that the eruption released between 0.3 to 0.5 teragrams of sulfur dioxide on April 17 and 18. These levels, while substantial, fall below the threshold generally required to affect global temperatures significantly.&nbsp;</p>



<p>For context, the 1991 Mount Pinatubo eruption, which had a pronounced cooling effect on the Earth's climate, released approximately 20 teragrams of sulfur dioxide.</p>



<h2 class="wp-block-heading" id="h-preparedness-and-future-risks">Preparedness and future risks</h2>



<p>In light of Ruang's active volcanic history and the potential for further eruptions, local authorities remain vigilant. The risk of lahars and tsunamis prompted immediate evacuations and multiple tsunami warnings, though, fortunately, no substantial tsunamis have occurred thus far. Over 16,000 residents have been evacuated from the most vulnerable areas, a move that has likely prevented any fatalities or serious injuries.</p>



<p>The 2024 <a href="https://www.earth.com/news/underwater-volcanic-eruptions-are-more-harmful-than-previously-believed/" target="_blank" rel="noreferrer noopener">eruption</a> of Ruang is a stark reminder of the powerful and often unpredictable nature of volcanic islands. While the local and immediate impacts are devastating, the eruption also offers valuable data for scientists studying the broader implications of such natural events on atmospheric conditions and climate. </p>



<h2 class="wp-block-heading" id="h-more-about-ruang">More about Ruang</h2>



<p>The population on Ruang is small, with residents primarily engaged in subsistence fishing and agriculture, which is typical of remote Indonesian islands. The island's terrain and soil fertility, influenced by volcanic ash, may support the cultivation of certain crops that are adapted to such conditions.</p>



<p>The Ruang volcano rises to about 725 meters above sea level, making it a prominent feature in the region. This area is part of the volcanic arc that includes numerous volcanoes produced by the subduction of the oceanic plate under the continental margin.</p>



<p>The active stratovolcano has had several recorded eruptions in history, with significant activity occurring in 1871, 1873, and 2002.&nbsp;</p>



<p>The image was captured by the Operational Land Imager (OLI) on April 20, 2024.</p>



<p>Image Credit: NASA Earth Observatory&nbsp;</p>



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Ruang volcano eruption has devastated the tranquil island

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features the Bermejo River and the Río Grande de Tarija, which flow through Argentina and Bolivia in South America. The photograph was captured by an astronaut onboard the International Space Station.</p>



<h2 class="wp-block-heading" id="h-meandering-rivers">Meandering rivers</h2>



<p>“The meandering rivers in this image are sourced in the Andes Mountains and generally flow southeast through valleys in the foothills - the region between the high mountains and plains. The Iruya River deposits particles of silt and clay as it flows into the valley centered in this image,” said NASA.</p>



<p>“Visible indications of the rivers’ shifting channels include river islands, point bars (on the inside curve of streams), and several meander scars. Such scars form when a river gets cut off from the main flow and fills in with sediment, soil, and vegetation.”</p>



<p>“Sediment from the adjacent highlands filled valleys that were formed by tectonic forces driving uplift of the Andes. These deposits are subsequently carried by rivers, such as the Iruya, along with new sediment to form the light-toned braided channels and the adjacent darker-toned floodplains. Nutrient-rich floodplain soils provide fertile ground for agricultural fields.”</p>



<h2 class="wp-block-heading" id="h-bermejo-river">Bermejo River</h2>



<p>The Bermejo River originates in the Bolivian <a href="https://www.earth.com/news/biodiversity-hotspots-are-shrinking-in-the-andes-mountains/" target="_blank" rel="noreferrer noopener">Andes</a> and flows into Argentina. It plays a crucial role in the geographical and ecological landscape of the region. The river's course is characterized by its meandering path through the Gran Chaco plain, making it a significant river in the region's hydrological system.</p>



<h3 class="wp-block-heading" id="h-economic-importance">Economic importance</h3>



<p>The Bermejo River is vital for agriculture, providing essential water resources for irrigation. It also has potential for hydroelectric power generation.</p>



<h3 class="wp-block-heading" id="h-biodiversity-nbsp">Biodiversity&nbsp;</h3>



<p>The diverse habitats created by the Bermejo River, including its riverbanks, floodplains, and adjacent forests, support rich biodiversity. However, the wildlife in this region faces threats from habitat destruction, pollution, and climate change, making conservation efforts critical for their survival.</p>



<p><a href="https://www.earth.com/news/jaguars-in-the-amazon-are-threatened-by-climate-extremes/" target="_blank" rel="noreferrer noopener">Jaguars</a> are the apex predators of this region, and are occasionally spotted along the riverbanks, where they hunt. Large, herbivorous mammals called tapirs are found in the forests around the Bermejo River. They often visit the river to drink and cool off.</p>



<p>Capibaras, the world’s largest rodents, are commonly found in the wetlands and along the river edges.</p>



<p>The tallest flying bird found in South and Central America, jabirus can often be seen in wetlands along the Bermejo River. Toco toucans, known for their colorful bills, can be found in the forested areas near the river.</p>



<h2 class="wp-block-heading" id="h-rio-grande-de-tarija">Río Grande de Tarija</h2>



<p>The Río Grande de Tarija, also known in its lower stretches as the Guadalquivir, flows primarily within Bolivia. It is a critical watercourse in the Tarija Department, contributing significantly to the region's agriculture and livelihoods.</p>



<h3 class="wp-block-heading" id="h-economic-importance-0">Economic importance</h3>



<p>This river is essential for irrigation, supporting a variety of crops and contributing to the local economy. The surrounding lands are fertile and productive, thanks to the river's water.</p>



<h3 class="wp-block-heading" id="h-challenges">Challenges</h3>



<p>Similar to other rivers, the Río Grande de Tarija faces challenges such as water management issues, <a href="https://www.earth.com/news/predicting-the-effects-of-pollutants-on-river-ecosystems/" target="_blank" rel="noreferrer noopener">pollution</a>, and the impacts of climate change on its flow and health.</p>



<h3 class="wp-block-heading" id="h-wildlife-in-bolivian-rivers">Wildlife in Bolivian rivers</h3>



<p>River basins in Bolivia are home to a wide range of bird species, including various species of herons, egrets, kingfishers, and perhaps even some rarer species like the wattled jacana or the sunbittern. The diverse birdlife is attracted to the abundance of fish and the relatively untouched natural habitats along the river.</p>



<p>The Characidae family includes many fish species that are commonly found in South American rivers, such as tetras. They are known for their diversity and are a key part of the river's ecosystem, serving as both <a href="https://www.earth.com/news/diving-to-extremes-predatory-fish-frequent-the-oceans-twilight-zone/" target="_blank" rel="noreferrer noopener">predator</a> and prey.</p>



<p>Cichlids are another diverse group of fish that can be found in South American rivers. They are appreciated by aquarium enthusiasts worldwide and play significant roles in their ecosystems as both predators and herbivores.</p>



<p>The rivers of Bolivia are also home to various catfish species, which are well adapted to life in muddy and turbulent waters. These include the armored catfish, which are often found clinging to rocks and logs.</p>



<p>Image Credit: NASA Earth Observatory/ ISS Crew Earth Observations Facility/ Earth Science and Remote Sensing Unit, Johnson Space Center</p>



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<h3 class="wp-block-heading" id="h-nbsp">&nbsp;</h3>

The Río Grande de Tarija and Bermejo River in South America

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features the delta of the Ebro River on the northeast coast of Spain, captured by the Copernicus Sentinel-2 mission.</p>



<h2 class="wp-block-heading" id="h-ebro-river">Ebro River</h2>



<p>“Stretching across 910 km of northern Spain, the Ebro River is the second-longest river in the Iberian Peninsula. In the image, it can be seen as a green line winding its way through the peninsula before flowing into the Mediterranean, shaping the Ebro Delta,” noted ESA.</p>



<p>“The Ebro River discharges more water into the sea than any other river in Spain. As suspended sediment flows from the river’s mouth, it tints the coastal waters with a turquoise hue.”</p>



<h2 class="wp-block-heading" id="h-ebro-delta">Ebro Delta</h2>



<p>The Ebro Delta is one of the largest <a href="https://www.earth.com/news/wetland-methane-emissions-have-surged-at-high-latitudes/">wetland areas</a> in the western Mediterranean region. The river's basin is the largest in Spain, covering about 85,000 square kilometers.</p>



<h2 class="wp-block-heading" id="h-historical-significance-nbsp">Historical significance&nbsp;</h2>



<p>Historically, the Ebro River has been significant in numerous battles, including the famous Battle of the Ebro during the Spanish Civil War, which was one of the war's longest and deadliest conflicts.&nbsp;</p>



<h2 class="wp-block-heading" id="h-economic-significance-nbsp">Economic significance&nbsp;</h2>



<p>Economically, the Ebro plays a crucial role in agriculture, particularly in regions like La Rioja and Navarre, which are known for their vineyards. Additionally, the river supports various industries and hydroelectric power generation.</p>



<h2 class="wp-block-heading" id="h-ecological-significance">Ecological significance</h2>



<p>The Ebro Delta is ecologically rich, providing habitat for diverse bird species. It is also a vital area for rice cultivation in Spain.&nbsp;</p>



<h3 class="wp-block-heading" id="h-nature-reserve">Nature reserve</h3>



<p>“Most of the delta comprises the Ebro Delta Nature Reserve. With its protected wetlands, beaches, marshes, salt pans and estuaries, this reserve provides a natural habitat for numerous migratory birds and waterfowl,” said ESA.</p>



<h3 class="wp-block-heading" id="h-environmental-challenges-nbsp">Environmental challenges&nbsp;</h3>



<p>The river and its delta face environmental challenges such as pollution, water extraction for irrigation, and the impacts of <a href="https://www.earth.com/news/climate-change-may-have-altered-river-flow-worldwide/">climate change</a>, which threaten its ecosystem and the sustainability of its water resources.</p>



<h2 class="wp-block-heading" id="h-the-northeast-coast-of-spain">The northeast coast of Spain</h2>



<p>The northeast coast of Spain is a vibrant and diverse region, characterized by its rich history, unique culture, and stunning landscapes. </p>



<p>It includes the autonomous communities of Catalonia, which features the dynamic city of Barcelona, and part of the Valencian Community. This area is also part of what is known as the Costa Brava, which stretches from the town of Blanes up to the French border.</p>



<h3 class="wp-block-heading" id="h-geography">Geography</h3>



<p>The <a href="https://www.earth.com/news/human-activity-impacts-97-percent-of-the-worlds-coastline/">coastline</a> is renowned for its rugged beauty, with rocky cliffs, secluded coves, and small beaches. The interior regions feature mountains such as the Pyrenees, which offer skiing in winter and hiking in the summer.</p>



<h3 class="wp-block-heading" id="h-cultural-heritage">Cultural heritage</h3>



<p>The area has a strong cultural identity, particularly in Catalonia, where there is a significant movement for independence. The Catalan language is widely spoken alongside Spanish. The region is also known for its festivals, architecture (notably the works of Antoni Gaudí in Barcelona), and traditional dances like the Sardana.</p>



<h3 class="wp-block-heading" id="h-cuisine">Cuisine</h3>



<p>The cuisine is a delightful mix of fresh seafood from the Mediterranean, traditional Catalan dishes like "pa amb tomàquet" (bread with tomato), and rice dishes such as paella in the Valencian region. The area is also famous for its wines, including the sparkling wine Cava.</p>



<h3 class="wp-block-heading" id="h-tourism">Tourism</h3>



<p>The northeast coast attracts millions of tourists each year due to its beautiful beaches, historical sites, and vibrant cities. Barcelona, in particular, is a major tourist destination with attractions like the Sagrada Familia, Park Güell, and the bustling La Rambla.</p>



<h3 class="wp-block-heading" id="h-economy">Economy</h3>



<p>The economy of the northeast coast is one of the most dynamic in Spain, with Barcelona serving as a major hub for trade, education, entertainment, and technology.</p>



<p>Image Credit: NASA Earth Observatory</p>



<p>-----</p>



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The Ebro River on the northeast coast of Spain

Abstract,Tech,Background.,Floating,Numbers,Hud,Background.,Matrix,Particles,Grid

<p>Scientists have discovered a novel method to manipulate light waves by deforming the two-dimensional photonic crystal that contains them. This discovery opens up new possibilities for the development of nanophotonic chips and has the potential to revolutionize the field of <a href="https://www.earth.com/news/new-data-transmission-speed-record-set-by-scientists-using-optical-cables/" target="_blank" rel="noreferrer noopener">photonics</a>, spawning new lasers and quantum devices.</p>



<h2 class="wp-block-heading" id="h-controlling-light-waves-with-photonic-crystals">Controlling light waves with photonic crystals</h2>



<p>A team of researchers from <a href="https://amolf.nl/" target="_blank" rel="noreferrer noopener">AMOLF</a>, in collaboration with <a href="https://www.tudelft.nl/en/" target="_blank" rel="noreferrer noopener">Delft University of Technology</a>, has successfully brought light waves to a halt by deforming the two-dimensional photonic crystal that contains them. </p>



<p>The researchers demonstrate that even a subtle deformation can have a substantial effect on photons in the crystal, resembling the effect that a magnetic field has on electrons.</p>



<p>"This principle offers a new approach to slow down light fields and thereby enhance their strength. Realizing this on a chip is particularly important for many applications," says AMOLF-group leader Ewold Verhagen.</p>



<h2 class="wp-block-heading" id="h-inspiration-and-lessons-learned-from-electrons">Inspiration and lessons learned from electrons</h2>



<p>The researchers drew inspiration from the way <a href="https://www.earth.com/news/attosecond-electron-freeze-frame-of-liquid-water-seen-for-the-first-time-ever/" target="_blank" rel="noreferrer noopener">electrons</a> behave in materials. In a conductor, electrons can move freely, but an external magnetic field can stop this motion. </p>



<p>The circular movement caused by the magnetic field stops conduction, and electrons can only exist in the material if they have very specific energies, known as Landau levels.</p>



<p>In <a href="https://www.earth.com/news/nanotech-material-graphene-passes-human-safety-tests/" target="_blank" rel="noreferrer noopener">graphene</a>, a two-dimensional material consisting of a single layer of carbon atoms arranged in a crystal, Landau levels can also be caused by a different mechanism than a magnetic field. </p>



<p>When the crystal array is deformed, such as by stretching it like elastics, conduction is stopped, and the material turns into an insulator, binding the electrons to Landau levels.</p>



<h2 class="wp-block-heading" id="h-applying-the-concept-to-photons">Applying the concept to photons</h2>



<p>The group of Verhagen, in collaboration with Kobus Kuipers of Delft University of Technology, demonstrated a similar effect for light in a photonic crystal.</p>



<p>"A photonic crystal normally consists of a regular -- two dimensional -- pattern of holes in a silicon layer. Light can move freely in this material, just like <a href="https://www.earth.com/news/electrons-in-graphene-exhibit-very-strange-fractional-behavior/">electrons i</a><a href="https://www.earth.com/news/electrons-in-graphene-exhibit-very-strange-fractional-behavior/" target="_blank" rel="noreferrer noopener">n</a><a href="https://www.earth.com/news/electrons-in-graphene-exhibit-very-strange-fractional-behavior/"> graphene</a>," says first author René Barczyk, who successfully defended his Ph.D. thesis on this topic in 2023. </p>



<p>"Breaking this regularity in exactly the right manner will deform the array and consequently lock the photons. This is how we create Landau levels for photons," Barczyk concluded.</p>



<p>In Landau levels, light waves no longer move; they stand still instead of flowing through the crystal. The researchers succeeded in demonstrating this, showing that the deformation of the crystal array has a similar effect on photons as a magnetic field on electrons.</p>



<h2 class="wp-block-heading" id="h-steering-light-waves-on-a-chip-with-deformation-patterns">Steering light waves on a chip with deformation patterns</h2>



<p>Verhagen says, "By playing with the deformation pattern, we even managed to establish various types of effective magnetic fields in one material. As a result, photons can move through certain parts of the material but not in others. Hence, these insights also provide new ways to steer light on a chip."</p>



<p>Simultaneously, a research team from <a href="https://www.psu.edu/" target="_blank" rel="noreferrer noopener">Pennsylvania State University</a> has published an article in the same journal about how they demonstrated -- independently from the Dutch team -- an identical effect. </p>



<p>While some details in the approach differed, both teams were able to stop light waves from moving and observe Landau levels by deforming a two-dimensional photonic crystal.</p>



<p>"This brings on-chip applications closer. If we can confine light at the nanoscale and bring it to a halt like this, its strength will be enhanced tremendously," Verhagen explained. </p>



<p>"And not only at one location, but over the entire crystal surface. Such light concentration is very important in nanophotonic devices, for example for the development of efficient lasers or <a href="https://www.earth.com/news/quantum-ping-pong-game-played-by-two-atoms-controlling-photons/" target="_blank" rel="noreferrer noopener">quantum light</a> sources," he concluded.</p>



<h2 class="wp-block-heading" id="h-controlling-light-waves-spawns-a-new-era-in-nanophotonics">Controlling light waves spawns a new era in nanophotonics</h2>



<p>The discovery of harnessing the power of deformation to control light waves marks a significant milestone in the field of nanophotonics. </p>



<p>By manipulating photonic crystals through subtle deformations, researchers have unlocked a new era of possibilities for on-chip applications, light concentration, and the development of efficient lasers and quantum light sources. </p>



<p>This breakthrough, independently confirmed by two research teams, paves the way for unprecedented control over light at the nanoscale, promising to revolutionize the future of photonics and open up exciting avenues for technological advancement.</p>



<p>The full study was published in the journal <em><a href="https://www.nature.com/articles/s41566-024-01412-3" target="_blank" rel="noreferrer noopener">Nature Photonics</a></em>.</p>



<p>-----</p>



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Quantum leap: Scientists make light waves 'stand still'

Scientists have discovered a novel method to manipulate light waves...

<p>The evolution of Earth's continental <a href="https://www.earth.com/news/unexpected-molten-rock-layer-discovered-under-earths-crust/" target="_blank" rel="noreferrer noopener">crust</a> during its early history holds clues to the dynamic processes that shaped our planet. For decades, scientists have debated over a significant change in crustal composition approximately 3 billion years ago. </p>



<p>While plate tectonics undoubtedly played a role, new research from <a href="http://english.gig.cas.cn" target="_blank" rel="noreferrer noopener">Guangzhou Institute of Geochemistry</a> challenges the notion of tectonic forces as the primary cause. It suggests a surprising role for increased heat within Earth's mantle.</p>



<h2 class="wp-block-heading" id="h-zircon-in-earth-s-geological-history">Zircon in Earth's geological history</h2>



<p>Zircon, an exceptionally resilient mineral, acts as a vital repository of Earth's geological history. These crystals originate within the depths of molten rock, capturing the conditions of their formation in their unique chemical makeup. </p>



<p>As zircon solidifies, it encapsulates isotopes of various elements such as oxygen, hafnium, and uranium. By examining these isotopes, scientists gain invaluable insights into the age and development of the Earth's crust. </p>



<p>This analysis enables researchers to construct a detailed chronology of geological events. It helps them understand the dynamic processes that have influenced the composition and structure of the continental crust over billions of years.</p>



<h2 class="wp-block-heading" id="h-earth-s-crust-rejuvenation">Earth's crust rejuvenation</h2>



<p>Geochemical analysis of zircon crystals revealed a significant shift in crustal composition approximately 3 billion years ago. This shift, marked by a change in specific isotopic ratios, indicates a process of crustal "rejuvenation" – the addition of newly formed material to older continental crust. </p>



<p>Traditionally, the rejuvenation of Earth's <a href="https://www.earth.com/news/who-is-drilling-a-hole-more-than-30000-feet-deep-in-the-earths-crust-and-why/" target="_blank" rel="noreferrer noopener">crust</a> has been attributed to an increase in global tectonic activity. This theory suggests that the movement of massive tectonic plates at the Earth's surface resulted in the recycling of older crustal materials. </p>



<p>However, the new research presents a different perspective. The study indicates that changes beneath the Earth's surface may have played a more significant role in rejuvenation than previously thought.</p>



<h2 class="wp-block-heading" id="h-role-of-mantle-heat">Role of mantle heat</h2>



<p>The research highlights a significant increase in heat emanating from Earth's mantle about three billion years ago. The boost in thermal energy could have been triggered by shifts in the radioactive decay processes within the mantle. </p>



<p>This led to a heightened release of heat. The consequences of increased mantle heat would have been dramatic for the crust lying above it. The intensified heat would cause the lower regions of the crust to undergo partial melting, ultimately resulting in the formation of magma pools at the crust-mantle boundary. </p>



<p>As this newly formed magma rose and interacted with the existing crustal materials, it would induce changes in the crust's composition. These alterations often result in the formation of new rock types and leave distinct geochemical signatures.</p>



<p>Such changes are particularly evident in zircon crystals found within these rocks. Zircon, with its ability to encapsulate and preserve the chemical fingerprints of its formation environment, serves as an excellent recorder of these processes. </p>



<p>By analyzing the isotopic and elemental composition of zircons, scientists can trace back these transformative events in the Earth's <a href="https://www.earth.com/news/mountain-terrain-below-earths-surface/" target="_blank" rel="noreferrer noopener">crust</a>, gaining insights into the dynamic interactions between the mantle's heat and the overlying crustal structures.</p>



<h2 class="wp-block-heading" id="h-reworking-of-earth-s-crust-and-continental-growth">Reworking of Earth's crust and continental growth</h2>



<p>The reworking of Earth's crust driven by increased mantle heat appears to have been a crucial factor in the expansion of the planet's continental landmasses. As the mantle heated up, it caused the lower crust to melt and generate buoyant magmatic materials. </p>



<p>The new materials, once solidified, added volume and buoyancy to the crust, effectively thickening it. This process likely contributed significantly to the creation and stabilization of large continental blocks.</p>



<p>The thickening of the crust through the addition of newly formed magmatic materials from deep within the Earth provides an alternative perspective to the traditional views that emphasize surface tectonic activities, such as plate movements, as the primary drivers of continental growth. </p>



<p>The heat-driven model emphasizes the importance of internal geodynamic processes, showing how deep Earth dynamics intricately connect to observable changes at the surface.</p>



<p>By acknowledging the role of mantle heat in shaping the <a href="https://www.earth.com/news/earths-ancient-breath-study-links-atmospheric-oxygen-and-mantle-chemistry/" target="_blank" rel="noreferrer noopener">Earth’s</a> continents, scientists highlight the interconnectedness of the planet’s interior processes with its exterior geological features. </p>



<p>This approach not only challenges the conventional focus solely on surface tectonics but also enriches our understanding of Earth’s geological history by demonstrating how subsurface conditions influence the development and evolution of continental structures.</p>



<h2 class="wp-block-heading" id="h-rethinking-earth-s-evolution">Rethinking Earth's evolution</h2>



<p>The research prompts a re-examination of our understanding of Earth's formative years. While subduction zones (where one tectonic plate dives beneath another) were active in the early Earth, their influence on crustal growth may have been complemented by deep mantle processes. </p>



<p>Elucidating the interplay between internal heat dynamics and surface tectonics is crucial for building a comprehensive model of our planet's evolution.</p>



<p>The study of ancient zircon crystals sheds light on the complex history of Earth's continental crust. While tectonic forces remain essential, this research underscores the importance of internal heat for shaping the continents we inhabit. </p>



<p>Continued investigation into Earth's deep history will undoubtedly refine our understanding of its remarkable transformation over billions of years and provide insights into the unique features that make our planet habitable.</p>



<p>The study is published in the journal <em><a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL108715" target="_blank" rel="noreferrer noopener">Geophysical Research Letters</a></em>.</p>



<p>-----</p>



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Mantle heat shaped Earth's crust 3 billion years ago

The evolution of Earth's continental crust during its early history...

<p>In the vast expanse of the universe, galaxies paint a breathtaking picture across the cosmic canvas. Among these celestial wonders, one galaxy stands out with its magnificent central bar and tightly wound spiral arms: NGC 2217.</p>



<p>Recently, the NASA/ESA <a href="https://science.nasa.gov/mission/hubble/" target="_blank" rel="noreferrer noopener">Hubble Space Telescope</a> captured a stunning image of NGC 2217, also known as AM 0619-271, in the constellation of Canis Major (The Greater Dog). </p>



<p>The barred spiral galaxy, roughly 65 million light-years from Earth, spans an impressive 100,000 light-years across, making it similar in size to our own <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">Milky Way</a>.</p>



<h2 class="wp-block-heading" id="h-the-luminous-heart-of-ngc-2217">The luminous heart of NGC 2217</h2>



<p>At the heart of NGC 2217 lies a luminous bar, where countless stars congregate, forming a brilliant central region. This bar plays a crucial role in the galaxy's evolution, acting as a cosmic funnel that channels gas from the disk into the core.</p>



<p>Dr. Emily Thompson, an astrophysicist at the <a href="https://www.cam.ac.uk/" target="_blank" rel="noreferrer noopener">University of Cambridge</a>, explains, "The central bar in galaxies like NGC 2217 is essential for their growth and development. It helps transport gas and dust to the center, where new stars can form or feed the supermassive black hole residing there."</p>



<h2 class="wp-block-heading">Nature of supermassive black holes</h2>



<p><a href="https://www.earth.com/news/largest-map-of-supermassive-black-holes-unveiled/" target="_blank" rel="noreferrer noopener">Supermassive black holes</a>, with masses ranging from millions to billions of times that of our Sun, reside at the center of most, if not all, large galaxies. </p>



<p>These cosmic behemoths, like the one growing at the heart of galaxy NGC 2217, exert an immense gravitational influence on their surroundings, shaping the structure and evolution of their host galaxies.</p>



<h3 class="wp-block-heading">Formation and growth</h3>



<p>The exact formation mechanism of supermassive black holes remains a topic of ongoing research. Scientists propose several theories, including the collapse of massive gas clouds in the early universe, the merging of <a href="https://www.earth.com/news/small-black-hole-disrupts-a-bigger-one-causing-cosmic-hiccups/" target="_blank" rel="noreferrer noopener">smaller black holes</a>, and the rapid accumulation of matter through accretion.</p>



<p>Supermassive black holes grow by consuming gas, dust, and stars that venture too close. As matter spirals towards the black hole, it forms an accretion disk, where friction and gravitational forces heat the material to extreme temperatures, causing it to emit intense radiation across the electromagnetic spectrum.</p>



<h3 class="wp-block-heading">Influence on galactic evolution</h3>



<p>Supermassive black holes play a crucial role in the evolution of galaxies. The energy released by the accretion process can trigger powerful outflows and jets, which can regulate star formation and shape the distribution of gas and dust within the galaxy.</p>



<p>In some cases, the feedback from supermassive black holes can quench star formation by heating and <a href="https://www.earth.com/news/supermassive-black-holes-are-very-messy-eaters/" target="_blank" rel="noreferrer noopener">expelling gas from the galaxy</a>. Conversely, the outflows can also compress gas clouds, triggering the birth of new stars in other regions.</p>



<p>"The interplay between the central bar, the inflowing gas, and the supermassive black hole is a complex and fascinating process," adds Dr. Thompson. "By studying galaxies like NGC 2217, we can gain a better understanding of how these cosmic giants evolve over time."</p>



<h2 class="wp-block-heading" id="h-colorful-collaboration">Colorful collaboration</h2>



<p>The stunning image of NGC 2217 was colorized using data from the Panoramic Survey Telescope and Rapid Response System (<a href="https://www2.ifa.hawaii.edu/research/Pan-STARRS.shtml" target="_blank" rel="noreferrer noopener">Pan-STARRS</a>). </p>



<p>This collaborative effort showcases the power of combining data from various astronomical instruments to create a more comprehensive picture of the universe.</p>



<p>Dr. Michael Johnson, a researcher at the Harvard-Smithsonian Center for Astrophysics (<a href="https://www.cfa.harvard.edu/" target="_blank" rel="noreferrer noopener">CfA</a>), emphasizes the importance of such collaborations. </p>



<p>"By combining data from the Hubble Space Telescope and Pan-STARRS, we can unlock new insights into the structure and composition of galaxies like NGC 2217. This synergy between telescopes allows us to push the boundaries of our understanding of the cosmos," Johnson enthused.</p>



<h2 class="wp-block-heading" id="h-ngc-2217-an-inspirational-window-to-the-cosmos">NGC 2217: An inspirational window to the cosmos</h2>



<p>As we gaze upon the magnificent central bar and tightly wound spiral arms of NGC 2217, we are reminded of the awe-inspiring beauty and complexity of the universe. </p>



<p>Through the lens of the Hubble Space Telescope and the collaborative efforts of astronomers worldwide, we continue to unravel the secrets of these cosmic masterpieces, one galaxy at a time.</p>



<p>-----</p>



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Hubble captures another cosmic masterpiece in galaxy NGC 2217

In the vast expanse of the universe, galaxies paint a...


<div class="vdb_player vdb_591c9e3c9efa894c3c6e150b58d96b98cd4fed198a0d2a49"><script type="text/javascript" src="//delivery.vidible.tv/jsonp/pid=591c9e3c9efa894c3c6e150b/vid=592ddc418d4c36762573fd59/58d96b98cd4fed198a0d2a49.js"></script></div>
<p>EPA researchers have developed three permeable surfaces and are investigating ways they can be used to help with stormwater management.</p>


Permeable Parking Lot Rain Garden