<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

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 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>



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The Ebro River on the northeast coast of Spain

<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 United Arab Emirates, where a slow-moving storm system dumped more than a year's worth of rainfall in just a few hours. </p>



<p>“The UAE’s National Center for Meteorology reported that eastern parts of the country measured up to 250 millimeters (10 inches) of rain in less than 24 hours. UAE, known for its dry desert climate, receives only about 140 to 200 millimeters (5.5 to 8 inches) of rainfall per year,” said NASA.</p>



<p>“Dubai International Airport recorded 119 millimeters on April 16, which is 1.5 times its typical annual rainfall. The deluge temporarily halted flights at the airport, which is among the world’s busiest for international travel.”</p>



<h2 class="wp-block-heading" id="h-heaviest-rainfall-on-record-in-the-united-arab-emirates-nbsp">Heaviest rainfall on record in the United Arab Emirates&nbsp;</h2>



<p>Authorities noted that this was the heaviest <a href="https://www.earth.com/news/record-heat-fueled-unexpected-and-deadly-storms-in-2023/" target="_blank" rel="noreferrer noopener">rainfall</a> on record in the United Arab Emirates. The news agency WAM called it a historic weather event that surpassed “anything documented since the start of data collection in 1949.”&nbsp;</p>



<p>“Heavy rain triggered flash flooding across eastern parts of the country, inundating roads and disrupting transportation,” said NASA. “The system first hit Oman on April 14 and continued to batter the UAE through most of the day on April 16.”&nbsp;</p>



<p>At least 18 people were killed in the <a href="https://www.earth.com/news/heavy-rainfall-events-in-the-northeast-are-set-to-increase-by-over-50-percent/" target="_blank" rel="noreferrer noopener">heavy rains</a> in Oman, including ten children that were swept away in a vehicle with one adult, according to a statement from the country’s National Committee for Emergency Management.&nbsp;</p>



<h2 class="wp-block-heading" id="h-strong-low-pressure-system">Strong low-pressure system</h2>



<p>Michael Mann, a climate scientist at the University of Pennsylvania, noted that three low-pressure systems formed a train of <a href="https://www.earth.com/news/thunderstorms-are-becoming-more-intense-due-to-climate-change/" target="_blank" rel="noreferrer noopener">storms</a> slowly moving along the jet stream - the river of air that moves weather systems - toward the Persian Gulf.&nbsp;</p>



<p>“The strong low-pressure system delivered multiple rounds of high winds and heavy rain to the northern and eastern parts of the country,” said NASA. “Some areas remained flooded on April 19, when Landsat 9 passed over the region for the first time since the storms.”&nbsp;</p>



<p>Climate experts attribute such extreme weather events to <a href="https://www.earth.com/news/limiting-global-warming-to-1-5-degrees-celsius-would-save-billions-of-lives/" target="_blank" rel="noreferrer noopener">global warming</a>. According to a report from Reuters, researchers anticipate that climate change will lead to hotter temperatures, increased humidity, and a greater risk of <a href="https://www.earth.com/news/seeking-ways-to-prevent-flooding-caused-by-climate-change/" target="_blank" rel="noreferrer noopener">flooding</a> in parts of the Gulf region. “Countries like the UAE where there is a lack of drainage infrastructure to cope with heavy rains can suffer the most,” the report stated.&nbsp;</p>



<h2 class="wp-block-heading" id="h-more-about-the-united-arab-emirates-nbsp">More about the United Arab Emirates&nbsp;</h2>



<p>The United Arab Emirates (UAE) is a federation of seven emirates located on the eastern side of the Arabian Peninsula. It borders Oman and Saudi Arabia, and has maritime borders with Iran and Qatar in the Persian Gulf. Established as a federation in 1971, the UAE has rapidly developed into one of the most modern and wealthy nations in the world, largely thanks to its vast oil and natural gas reserves.</p>



<p>Abu Dhabi serves as the capital and is the largest emirate, both in terms of land area and economy, largely because it holds the majority of the UAE's oil reserves. Dubai is the most populous city and is renowned globally for its spectacular skyscrapers, including the Burj Khalifa, the tallest building in the world, as well as its bustling ports, and vibrant tourism and shopping sectors.</p>



<p>The UAE has a diverse and multicultural society with a significant expatriate population, drawn by business opportunities and the tax-free living in many sectors. The official language is Arabic, though English is widely spoken, especially in business and educational settings.</p>



<p>Politically, the UAE is a federal absolute monarchy. It is governed by a Supreme Council of Rulers made up of the seven emirs, who appoint the prime minister and the cabinet. The country has made significant strides in terms of infrastructure and healthcare, and it continues to invest heavily in various sectors including renewable energy, education, and technology.</p>



<p>Culturally, the UAE balances its rapid modernization with a strong commitment to traditional Arab culture. The heritage of the desert Bedouin lifestyle is celebrated with falconry, camel racing, and traditional dance remaining integral to its cultural festivities. The nation is also a major hub for international arts and sports events, enhancing its global profile and cultural footprint.</p>



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



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Storms dumped record rainfall in the United Arab Emirates

<p>A recent study led by the <a href="https://alleninstitute.org/division/brain-science/" target="_blank" rel="noreferrer noopener">Allen Institute for Brain Science</a> has advanced our understanding of how the brain's specialized <a href="https://www.earth.com/news/human-brains-compensate-aging-dementia-recruiting-other-brain-regions-to-help/">regions</a> develop their unique functions. </p>



<p>By employing a cutting-edge method called BARseq to extensively map neurons across nine mouse brains, the experts provided unique insights into the brain's cellular landscape.</p>



<h2 class="wp-block-heading" id="h-specialized-subregions-of-the-brain">Specialized subregions of the brain</h2>



<p>“The vertebrate brain is organized into subregions that are specialized in function and distinct in cytoarchitecture and connectivity. This spatial specialization of function and structure is established by developmental processes involving intrinsic genetic programs and/or external signaling,” wrote the study authors.&nbsp;</p>



<p>“Although gene expression can change during cell maturation and remains dynamic in response to internal cellular conditions and external stimuli, a core transcriptional program that maintains cellular identity usually remains steady in mature neurons.”&nbsp;</p>



<p>“Thus, resolving the expression of core sets of genes that distinguish different types of neuron provides insight into the functional and structural specialization of neurons.”</p>



<h2 class="wp-block-heading" id="h-unique-cellular-signatures-of-specialized-brain-regions">Unique cellular signatures of specialized brain regions</h2>



<p>The team discovered that while different brain regions contain similar types of neurons, each region possesses a distinct combination of these cells, effectively giving each area a unique cellular “signature.” This finding is a significant step forward in understanding the complex organization of the brain.</p>



<p>Additionally, the study explored how the absence of <a href="https://www.earth.com/news/emotions-sensory-perception-brain-fascinating-interplay/" target="_blank" rel="noreferrer noopener">sensory inputs</a>, such as sight, affects these cellular signatures. “BARseq lets us see with unprecedented precision how sensory inputs affect brain development. These broad changes illustrate how important <a href="https://www.earth.com/news/blinking-plays-crucial-role-vision-human-perception/" target="_blank" rel="noreferrer noopener">vision </a>is in shaping our brains, even at the most basic level,” said co-lead author Xiaoyin Chen, an Assistant Investigator at the Allen Institute. </p>



<h2 class="wp-block-heading" id="h-sensory-inputs-and-brain-development">Sensory inputs and brain development</h2>



<p>The researchers found that mice deprived of sight experienced a significant reorganization of cell types within the visual cortex, which blurred the distinctions with neighboring areas. This reorganization was observed across half of the cortical regions, although to a lesser extent.</p>



<p>BARseq, which stands out for its efficiency and cost-effectiveness, enables the tagging of individual brain cells with unique RNA “barcodes.” This allows for tracking connections across the brain and analyzing gene expression to identify large numbers of neurons in tissue slices. “BARseq lets us see with unprecedented precision how sensory inputs affect brain development,” Chen elaborated.</p>



<h2 class="wp-block-heading" id="h-mapping-millions-of-brain-cells">Mapping millions of brain cells</h2>



<p>Study co-leader Mara Rue, a scientist at the Allen Institute, highlighted the advantages of BARseq over other mapping technologies. “Previously, capturing single-cell data across multiple brains was challenging,” she said. Fortunately, BARseq simplifies this process, making it more accessible for a broader range of researchers.</p>



<p>In just three weeks, the researchers were able to map more than 9 million cells from eight brains, demonstrating the method's rapid capabilities. “BARseq allows us to move beyond mapping what a ‘model’ or ‘standard’ brain looks like and start to use it as a tool to understand how brains change and vary,” Chen explained. “With this throughput, we can now ask these questions in a very systematic way, something unthinkable with other techniques.”</p>



<h2 class="wp-block-heading" id="h-broader-study-implications-nbsp">Broader study implications&nbsp;</h2>



<p>Both Chen and Rue hope that making the BARseq method freely available will encourage its use across the scientific community, allowing more researchers to explore the brain’s organizational principles or delve into cell types associated with <a href="https://www.earth.com/news/air-pollution-may-cause-brain-disorders/%C3%B9" target="_blank" rel="noreferrer noopener">diseases</a>. </p>



<p>“This isn’t something that only the big labs can do. Our study is a proof of principle that BARseq allows a wide range of people in the field to use spatial transcriptomics to answer their own questions.”</p>



<h2 class="wp-block-heading" id="h-more-about-specialized-brain-regions">More about specialized brain regions</h2>



<p>The human brain is an incredibly complex organ composed of various specialized regions, each responsible for different functions.&nbsp;</p>



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



<p>The frontal lobes, positioned at the front of the brain, are crucial for cognitive functions like <a href="https://www.earth.com/news/brain-cells-communicate-to-support-decision-making/" target="_blank" rel="noreferrer noopener">decision-making</a>, problem-solving, and controlling behavior and emotions. </p>



<h3 class="wp-block-heading" id="h-parietal-lobes">Parietal lobes</h3>



<p>The parietal lobes, located in the middle section of the brain, play essential roles in processing sensory information and helping with spatial orientation and manipulation.</p>



<h3 class="wp-block-heading" id="h-temporal-lobes">Temporal lobes</h3>



<p>The temporal lobes, found on the sides of the brain, are key for processing auditory information and are also critically involved in memory storage. Meanwhile, the occipital lobes at the back of the brain are primarily responsible for visual processing, interpreting everything we see.</p>



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



<p>In addition to these lobes, the cerebellum, situated beneath the rear portion of the cerebrum, is vital for motor control and coordination. The brainstem, connecting the brain to the spinal cord, governs many automatic functions necessary for survival, such as breathing, heart rate, and blood pressure.</p>



<h3 class="wp-block-heading" id="h-more-specialized-areas">More specialized areas</h3>



<p>Furthermore, within these larger regions are more specialized areas, like Broca's area in the frontal lobe, crucial for speech production, and Wernicke's area in the temporal lobe, important for understanding language. The hippocampus, deeply embedded in the temporal lobe, is essential for forming new memories.</p>



<p>Each of these regions works in concert with the others, forming a highly interconnected and dynamic network that enables everything from simple reflexes to complex thought processes.</p>



<p>The research is published in the journal <a href="http://dx.doi.org/10.1038/s41586-024-07221-6" target="_blank" rel="noreferrer noopener"><em>Nature</em></a><em>.</em></p>



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



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How do specialized regions develop in the brain?

A recent study led by the Allen Institute for Brain...

<p><a href="https://www.earth.com/news/sex-impacts-gene-expression/" target="_blank" rel="noreferrer noopener">Sexual dimorphism</a>, which is the observable difference in appearance between male and female members of a species, occurs widely across the animal kingdom, including in humans. An interesting variation of this is sex-limited polymorphism, where one sex exhibits more variation in a certain trait compared to the other. </p>



<p>An international team of scientists has explored this concept by examining the genetic basis for color polymorphism in adult female <a href="https://www.earth.com/news/cuckoos-are-unable-to-change-their-migrations-in-response-to-climate-change/" target="_blank" rel="noreferrer noopener">cuckoos</a> of the genus <em>Cuculus</em>, which are known for their brood parasitic behavior. The research provides insights into the evolutionary development and practical implications of this trait variation.</p>



<h2 class="wp-block-heading" id="h-genetic-basis-of-female-cuckoo-colors">Genetic basis of female cuckoo colors</h2>



<p>The scientists examined why adult female cuckoos, unlike their uniformly gray male counterparts, may exhibit either gray or rufous (reddish-brown) plumage. This variability is not only evident across different cuckoo species but also within populations of the same species.</p>



<p>Using genome-wide association analysis on nuclear DNA from both Common and Oriental cuckoos, the researchers aimed to pinpoint the genetic factors behind the females' diverse plumage in an attempt to understand the underlying pigmentation mechanisms and the evolutionary history of these <a href="https://www.earth.com/news/scientists-wonder-evolutionary-success/" target="_blank" rel="noreferrer noopener">traits</a>.</p>



<p>In <a href="https://www.earth.com/news/untold-story-of-bird-evolution-revealed-through-genetics/" target="_blank" rel="noreferrer noopener">birds</a>, unlike in mammals, it is the females that are heterogametic (ZW), differing from the homogametic males (ZZ). This led researchers to speculate that the observed color variation in female cuckoos might be linked to genes on the W chromosome. </p>



<p>“We found that, instead of a single gene or set of genes, nearly all variations in the gray or rufous coloration were associated with the full length of the female-limited W chromosome,” said co-author Mark Haber, the executive director of the <a href="https://asrc.gc.cuny.edu/" target="_blank" rel="noreferrer noopener">CUNY Advanced Science Research Center</a> (CUNY ASRC) and a psychology professor at the <a href="https://www.gc.cuny.edu/" target="_blank" rel="noreferrer noopener">CUNY Graduate Center</a>.</p>



<h2 class="wp-block-heading" id="h-biochemical-processes-of-cuckoo-colors">Biochemical processes of cuckoo colors</h2>



<p>The scientists also examined the biochemical processes of coloration, revealing that both the Common and Oriental cuckoos use two forms of melanin-based pigmentation - similar to that in human skin - to produce their <a href="https://www.earth.com/news/for-songbirds-bright-colors-are-a-blessing-and-a-curse/" target="_blank" rel="noreferrer noopener">color</a> variations. </p>



<p>Further genomic analysis of these species traced the origin of the color polymorphism in female cuckoos to a mutation that occurred over one million years ago, long before these species diverged around 140,000 years ago.</p>



<h2 class="wp-block-heading" id="h-potential-advantages-of-female-cuckoo-coloration-nbsp">Potential advantages of female cuckoo coloration&nbsp;</h2>



<p>The implications of these color variations are profound. For instance, female cuckoos with the rarer rufous plumage might benefit from mimicking juvenile cuckoos to avoid male harassment during mating seasons.&nbsp;</p>



<p>Moreover, as brood parasites who lay their eggs in the nests of other bird species, rufous females could potentially escape detection by host species better than their gray counterparts, which might reduce the risk of being attacked by host parents.</p>



<p>“The fascinating idea that many other sex-specific traits, which are harder to study, might also be genetically determined in the matrilinear genome, similar to the color polymorphism in female cuckoos,” concluded senior author Jochen Wolf, an expert in evolutionary biology at LMU Munich.</p>



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



<p>Cuckoo birds are known for their distinctive calls and unique breeding behavior, particularly their practice of brood parasitism. This involves laying their eggs in the nests of other bird species, leaving the unsuspecting host birds to raise the cuckoo's offspring.&nbsp;</p>



<p>As a result, the host species may inadvertently neglect their own young due to the demanding nature of the cuckoo chick, which often grows larger than its foster siblings.</p>



<p>Cuckoos are found across the world and are highly adaptable to various environments. The family Cuculidae, to which they belong, includes both brood-parasitic cuckoos as well as species that raise their own young. Their diet varies from insects to caterpillars, and some species also consume fruits and seeds.</p>



<p>The cuckoo's call, which gives them their name, is emblematic in culture and often signals the arrival of spring. The most commonly recognized call is that of the common cuckoo in Europe, famously captured in the phrase "cuck-oo." </p>



<p>This sound has not only embedded them in folklore but also inspired the creation of the cuckoo clock, where the bird's call marks the passing hours.</p>



<p>The study is published in the journal <a href="http://dx.doi.org/10.1126/sciadv.adl5255" target="_blank" rel="noreferrer noopener"><em>Science Advances</em></a><em>.</em></p>



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Female cuckoo colors provide evolutionary advantages

Sexual dimorphism, which is the observable difference in appearance between...

<p>Recent research using the James Webb Space Telescope (<a href="https://webb.nasa.gov/" target="_blank" rel="noreferrer noopener">JWST</a>) has provided new insights into the early stages of <a href="https://www.earth.com/news/black-holes-shaped-the-universe-before-galaxies-existed/" target="_blank" rel="noreferrer noopener">galaxy</a> formation, suggesting that galaxies evolved significantly faster and were less chaotic than previously believed. </p>



<p>This discovery challenges long-standing theories about the early Universe, which was thought to be tumultuous with frequent collisions and unformed stars.</p>



<h2 class="wp-block-heading" id="h-through-the-cosmic-lens-jwst-s-revolutionary-observations">Through the cosmic lens: JWST's revolutionary observations</h2>



<p>The JWST, a successor to the Hubble Space Telescope and the largest and most powerful space telescope ever constructed, allowed astronomers to observe galaxies as they existed between eight to 11.5 billion years ago. </p>



<p>Remarkably, this period is just a couple of billion years after the formation of the Universe, which is estimated to be 13.7 billion years old.</p>



<p>An international team of astronomers, including researchers from <a href="https://www.dur.ac.uk/" target="_blank" rel="noreferrer noopener">Durham University</a> in the UK, utilized the advanced capabilities of the JWST to detect bar formations in these <a href="https://www.earth.com/news/ancient-galaxy-jwst-er1g-dark-matter-einstein-ring-mystery-solved/" target="_blank" rel="noreferrer noopener">ancient galaxies</a>. </p>



<h2 class="wp-block-heading" id="h-understanding-galaxy-evolution">Understanding galaxy evolution </h2>



<p>Bars, which are elongated strips of stars within disc or spiral galaxies, play a crucial role in the maturation of galaxies by directing gas towards the central regions and fostering star formation.</p>



<p>"The presence of a stellar bar in a disc galaxy indicates that the galaxy hosts in its main part a dynamically settled disc and that bar-driven processes are taking place in shaping its evolution," wrote the researchers.</p>



<p>"Studying the cosmic evolution of the bar fraction in disc galaxies is therefore essential to understand galaxy evolution in general." </p>



<h2 class="wp-block-heading" id="h-surprising-galactic-maturity">Surprising galactic maturity</h2>



<p>The team's observations revealed that almost 20 percent of the 368 disc galaxies studied exhibited bars - double the proportion observed in previous studies using the Hubble Space Telescope. </p>



<p>Zoe Le Conte, the lead author and a PhD researcher at Durham University’s Centre for Extragalactic Astronomy, expressed surprise at the findings. She stated: "Galaxies in the early <a href="https://www.earth.com/news/ceers-2112-ancient-galaxy-looks-strikingly-similar-to-ours/" target="_blank" rel="noreferrer noopener">Universe</a> are maturing much faster than we thought. This is a real surprise because you would expect the Universe at that stage to be very turbulent."</p>



<p>"We find that many more bars were present in the early Universe than previously found in Hubble studies, implying that bar-driven galaxy evolution has been happening for much longer than previously thought," noted study co-author Dr. Dimitri Gadotti. </p>



<h2 class="wp-block-heading" id="h-implications-for-galaxy-evolution-theories">Implications for galaxy evolution theories</h2>



<p>These findings necessitate a reevaluation of existing models of galaxy <a href="https://www.earth.com/news/massive-galactic-explosion-provides-clues-about-galaxy-evolution/" target="_blank" rel="noreferrer noopener">evolution</a>. The presence of bars in such a high percentage of early galaxies indicates a more settled phase in their development, contrary to the previously held belief of a chaotic early Universe. </p>



<p>"The fact that there are a lot more bars is what’s very exciting," said Dr. Gadotti. Moreover, the research team plans to delve deeper into the cosmic timeline, aiming to explore bar formation in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxies</a> even further back in time, up to 12.2 billion years ago. </p>



<p>This could provide further clues about the mechanisms behind bar growth and its impact on galaxy evolution.</p>



<h2 class="wp-block-heading" id="h-beyond-the-horizon-future-galactic-explorations">Beyond the horizon: Future galactic explorations</h2>



<p>Durham University has played a significant role in the scientific development of the JWST, particularly through its contributions to the Mid-Infrared Instrument (MIRI) and the optics for the Near Infrared Spectrograph's Integral Field Unit. These instruments are pivotal in probing the mysteries of galaxies and black holes.</p>



<p>As researchers continue to harness the JWST's unprecedented capabilities, our understanding of the Universe's earliest days is set to expand, potentially rewriting the cosmic rulebook on galaxy formation and evolution. </p>



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



<p>Galaxy evolution is like a cosmic dance, where galaxies, vast collections of stars, gas, and dust, change and morph over billions of years. It's a grand narrative of birth, growth, and sometimes even destruction. </p>



<p>Galaxies come in different shapes and sizes, from majestic spirals to more amorphous ellipticals, each with its own story to tell. Gravity plays a starring role, pulling galaxies together into groups and clusters, fostering mergers and collisions that can dramatically reshape their structures. </p>



<p>Through these encounters, galaxies exchange material, triggering bursts of star formation or feeding supermassive black holes lurking at their centers. </p>



<p>Over time, galaxies age and evolve, their populations of stars changing as old stars fade away and new ones are born. Yet, amidst this dynamism, there's a certain elegance to the cosmic ballet, as galaxies continue their journey through the vast expanse of the universe, leaving behind clues to their histories for astronomers to decipher.</p>



<p>The study is published in the journal <em><a href="https://academic.oup.com/mnras/article/530/2/1984/7653430" target="_blank" rel="noreferrer noopener">Monthly Notices of the Royal Astronomical Society</a></em>.</p>



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Early galaxy formation occurred much faster than we thought

Recent research using the James Webb Space Telescope (JWST) has...

<p></p>
<div id="58e3ebce955a315103d39bd1" class="vdb_player vdb_58e3ebce955a315103d39bd158d96b98cd4fed198a0d2a49" vdb_params="m.embeded=cms_video_plugin_www.earth.com"  data-placeholder="//img.vidible.tv/prod/2018-09/12/5b99a64a0153016af1c411c9/5b99a652eac4105b0afe95be_o_A_v2.jpg?w=3780&#038;h=2362&#038;q=60">
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<p>                <span style="font-weight: 400;">Today&#8217;s </span><b>Video of the Day</b><span style="font-weight: 400;"> from the </span><a href="https://www.acs.org/content/acs/en.html"><span style="font-weight: 400;">American Chemical Society</span></a><span style="font-weight: 400;"> series </span><i><span style="font-weight: 400;">Reactions</span></i><span style="font-weight: 400;"> describes the composition of the gunk that forms in our eyes while we are asleep. </span></p>
<p><span style="font-weight: 400;">This mysterious substance is made up of a three-layer combination of protein, oils, skin cells, and bacteria. </span></p>
<p><span style="font-weight: 400;">The outermost layer of the gunk is called meibum, an oily complex that helps keep the eyes from drying out. </span></p>
<p><span style="font-weight: 400;">During the day, eye gunk develops but is discarded as we blink. At night, it builds up and dries out in the corners of our eyes.</span></p>
<p><span style="font-weight: 400;">&#8212;</span></p>
<p><i><span style="font-weight: 400;">By </span></i><a href="http://csexton@earth.com"><i><span style="font-weight: 400;">Chrissy Sexton</span></i></a><i><span style="font-weight: 400;">, </span></i><a href="https://www.earth.com/staff/"><i><span style="font-weight: 400;">Earth.com</span></i></a><i><span style="font-weight: 400;"> Staff Writer </span></i></p>
<p><i><span style="font-weight: 400;">Video Credit: American Chemical Society</span></i></p>

What is the gunk that forms in our eyes during sleep?