<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>Today's <strong>Image of the Day</strong> from the <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">European Space Agency </a>features the barred spiral galaxy NGC 3783, which is located about 130 million light-years away in the constellation Centaurus. NGC 3783 is also the most prominent of a galaxy group (by the same name) that contains 47 <a href="https://www.earth.com/news/james-webb-captures-galaxies-that-are-too-old-to-exist/" target="_blank" rel="noreferrer noopener">galaxies</a>. </p>



<h2 class="wp-block-heading" id="h-galaxy-groups">Galaxy groups</h2>



<p>“Like galaxy clusters, galaxy groups are aggregates of gravitationally bound galaxies. Galaxy groups, however, are less massive and contain fewer members than <a href="https://www.earth.com/news/titanic-galaxy-cluster-collision-defies-all-current-understanding-of-the-universe/" target="_blank" rel="noreferrer noopener">galaxy clusters</a> do: where galaxy clusters can contain hundreds or even thousands of constituent galaxies, galaxy groups do not typically include more than 50,” noted ESA.</p>



<p>“The Milky Way is actually part of a galaxy group, known as the Local Group, which contains two other large galaxies (Andromeda and the Triangulum galaxy), as well as several dozen satellite and dwarf galaxies.”</p>



<h2 class="wp-block-heading" id="h-hd-101274-a-blue-giant-star">HD 101274: A blue giant star</h2>



<p>The bright object that appears to the right of the galaxy is the star HD 101274. “The perspective in this image makes the star and the galaxy look like close companions, but this is an illusion. HD 101274 lies only about 1,530 light-years from Earth, meaning it is about 85 thousand times closer than NGC 3783,” explained ESA.&nbsp;</p>



<p>HD 101274 is part of the NGC 3766 cluster, which is sometimes referred to as the Pearl Cluster, an open cluster known for its richness in bright stars and its relatively young age.</p>



<p>HD 101274 is categorized as a blue giant star, characterized by its high temperature and luminosity. Blue giants are massive stars that have left the main sequence phase of stellar evolution and are burning helium or heavier elements in their cores. These stars are known for their short lifespans relative to smaller stars due to their rapid consumption of nuclear fuel.</p>



<p><a href="https://www.earth.com/news/dark-stars-scientists-discover-a-new-type-of-star-powered-by-dark-matter/" target="_blank" rel="noreferrer noopener">Stars</a> like HD 101274 are important for astronomers because they help in studying the properties of stellar populations in clusters and the dynamics of stellar evolution in different environments. The spectral and photometric observations of such stars can provide valuable insights into the characteristics of their atmospheres, internal structures, and the processes occurring within and around them.</p>



<h2 class="wp-block-heading" id="h-bright-central-region-of-ngc-3783">Bright central region of NGC 3783</h2>



<p>One of the most interesting aspects of NGC 3783 is that it harbors an active galactic nucleus, meaning its central region is exceptionally luminous, likely due to the presence of a supermassive black hole. This black hole is actively accreting material, which emits a substantial amount of radiation as it spirals inward and heats up.</p>



<p>This galaxy is particularly known for its bright central region and has been studied extensively in the ultraviolet and X-ray light spectra to understand better the properties of the accretion disk around the black hole and the complex dynamics of the material surrounding it. These studies are crucial for understanding the physics of active galactic nuclei and the role they play in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>.</p>



<p>According to ESA, NGC 3783 is a Type I Seyfert galaxy. “In this image it is recorded by Hubble in incredible detail, from its glowing central bar to its narrow, winding arms and the dust threaded through them, thanks to five separate images taken in different wavelengths of light," noted ESA.</p>



<p>“In fact, the galactic center is bright enough to Hubble that it exhibits diffraction spikes, normally only seen on stars such as HD 101274.”</p>



<h2 class="wp-block-heading" id="h-more-about-the-ngc-3783-galaxy-group">More about the NGC 3783 galaxy group</h2>



<p>The NGC 3783 group is part of the larger Hydra-Centaurus Supercluster, which itself is a massive collection of galaxies and galaxy clusters located primarily in the constellations of Hydra and Centaurus.</p>



<p>The NGC 3783 group consists of several galaxies that are gravitationally bound and interact with each other. These interactions can influence the galaxies' evolution through mechanisms like tidal forces and merger events, which can trigger star formation, fuel central black holes, and reshape the galaxies' structures.</p>



<p>Studying groups like the NGC 3783 group helps astronomers understand how <a href="https://www.earth.com/news/ceers-2112-ancient-galaxy-looks-strikingly-similar-to-ours/" target="_blank" rel="noreferrer noopener">galaxies</a> evolve together in a common gravitational environment, offering insights into the dynamics and evolution of structures on cosmic scales. This is especially relevant in understanding how galaxies influence each other through gravitational interactions and the environmental effects on galaxy evolution.</p>



<p>Image Credit: ESA/Hubble &amp; NASA</p>



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The luminous galaxy NGC 3783 and a blue giant star

Today's Image of the Day from the European Space Agency...

<p>The thing confusing archaeologists was that Chankillo&nbsp;<em>couldn’t&nbsp;</em>have operated as a normal fort — if it was a fort at all. A glance at its three buildings revealed to the experts that they would be easily penetrable by invading forces. The solid construction evidently had some serious flaws. Photo Credit: Werner Forman/Universal Images Group/Getty Images</p>

Open sesame

<p>A team of biologists led by the <a href="https://uol.de/en" target="_blank" rel="noreferrer noopener">University of Oldenburg</a> in Germany has recently made significant strides in understanding how <a href="https://www.earth.com/news/migratory-birds-have-new-strategy-to-cope-with-climate-change/" target="_blank" rel="noreferrer noopener">migratory birds</a> navigate with remarkable accuracy. </p>



<p>The research, which also included experts from the <a href="https://ifv-vogelwarte.de/en/home" target="_blank" rel="noreferrer noopener">Institute of Avian Research “Vogelwarte Helgoland”</a>, was focused on the role of a specific protein in birds’ eyes, believed to be a key magnetoreceptor enabling this navigation. </p>



<h2 class="wp-block-heading" id="h-genetic-basis-of-how-birds-navigate-nbsp">Genetic basis of how birds navigate&nbsp;</h2>



<p>The researchers compared the genomes of several hundred bird species and observed notable evolutionary changes in the gene encoding the protein cryptochrome 4. They found that certain groups of birds have completely lost this gene.&nbsp;</p>



<p>“This suggests that the protein is important for adaptation to specific environmental conditions,” said senior author Miriam Liedvogel, the director of the Institute of Avian Research. “A similar pattern has been observed in other sensory proteins such as light-sensitive pigments in the eye.”</p>



<h2 class="wp-block-heading" id="h-magnetoreception-in-birds">Magnetoreception in birds</h2>



<p>Previous research revealed that magnetoreception in birds is linked to a complex quantum mechanical process in the <a href="https://www.earth.com/news/rare-retinal-cells-explain-complex-color-perception/" target="_blank" rel="noreferrer noopener">retina</a>. </p>



<p>For instance, a 2021 study suggested cryptochrome 4 as the probable magnetoreceptor, showing that it is present in the retina and responds to magnetic fields with a quantum effect, an ability more pronounced in robins than in non-migratory birds like chickens and pigeons.</p>



<p>“Consequently, the reason why cryptochrome 4 is more sensitive in robins than in chickens and pigeons must be found in the protein’s DNA sequence,” explained lead author Corinna Langebrake, a researcher at the Institute of Avian Research. “The sequence was probably optimized by evolutionary processes in these nocturnal migratory birds.”</p>



<h2 class="wp-block-heading" id="h-the-role-of-cryptochrome-4">The role of cryptochrome 4</h2>



<p>In the current study, the team examined the cryptochrome 4 genes across 363 bird species, from the little spotted kiwi to the song sparrow.&nbsp;</p>



<p>They compared the evolutionary rate of cryptochrome 4 with that of other related proteins and found that while other cryptochromes have changed little over time due to their crucial role in regulating the <a href="https://www.earth.com/news/internal-clock-living-human-cells/" target="_blank" rel="noreferrer noopener">internal clock</a>, cryptochrome 4 showed high variability. This variability suggests a specialized function, potentially as a magnetoreceptor. </p>



<p>“A similar pattern has been observed in other sensory proteins such as light-sensitive pigments in the eye,” Liedvogel said. Particularly among passerine birds, the protein appears to have undergone rapid selection, further supporting its specialized role in magnetoreception.</p>



<h2 class="wp-block-heading" id="h-alternative-mechanisms-of-magnetoreception">Alternative mechanisms of magnetoreception</h2>



<p>Interestingly, the study also found that three clades of tropical birds - <a href="https://www.earth.com/news/saving-parrots-in-the-illegal-wildlife-trade-with-dna-technology/" target="_blank" rel="noreferrer noopener">parrots</a>, hummingbirds, and Tyranni (suboscines), known as tyrants - have lost the gene for cryptochrome 4, indicating it may not be essential for their survival. </p>



<p>Since some tyrants are long-distance migrants, their lack of cryptochrome 4 presents an opportunity to explore alternative mechanisms of magnetoreception.</p>



<h2 class="wp-block-heading" id="h-do-some-birds-navigate-without-any-magnetic-sense">Do some birds navigate without any magnetic sense?</h2>



<p>“The fact that, unlike robins, they do not have cryptochrome 4 makes them an ideal system for investigating various hypotheses about magnetoreception,” Langebrake explained.&nbsp;</p>



<p>A key question is whether the Tyranni have evolved a magnetic sense that functions without the cryptochrome 4 protein, or if they can navigate without relying on any magnetic sense at all.&nbsp;</p>



<p>Additionally, it's possible that their magnetic sensing capabilities mirror those found in robins, which rely on light and can be influenced by external factors such as radio waves.</p>



<p>“The first two scenarios would strongly corroborate the cryptochrome 4 hypothesis, while the third would pose a problem for the theory,” she added.</p>



<h2 class="wp-block-heading" id="h-magnetoreception-and-bird-navigation-nbsp">Magnetoreception and bird navigation&nbsp;</h2>



<p>Moving forward, the research team plans to investigate magnetic orientation in Tyranni to better understand the function of cryptochrome 4 and its importance in magnetoreception among migratory birds.&nbsp;</p>



<p>This research not only deepens our understanding of <a href="https://www.earth.com/news/birds-magnetic-field-navigate/" target="_blank" rel="noreferrer noopener">avian navigation</a> but also opens new avenues for exploring evolutionary adaptations in sensory perception.</p>



<h2 class="wp-block-heading" id="h-more-about-how-birds-navigate-nbsp">More about how birds navigate&nbsp;</h2>



<p>Migratory birds have remarkable abilities to navigate across vast distances, often traveling thousands of miles between breeding and wintering grounds. Their navigation skills are attributed to a variety of mechanisms:</p>



<h3 class="wp-block-heading" id="h-sun-compass">Sun compass</h3>



<p>Birds use the sun as a compass. They can gauge the time of day and adjust their flight direction based on the sun's position in the sky.</p>



<h3 class="wp-block-heading" id="h-star-compass">Star compass</h3>



<p>During night migration, many birds use the stars to navigate. They can identify constellations and use them to maintain their flight path.</p>



<h3 class="wp-block-heading" id="h-geomagnetic-field">Geomagnetic field</h3>



<p>Birds are sensitive to Earth's geomagnetic field. They have magnetoreceptors that allow them to sense magnetic fields, which helps them determine their latitude and longitude for orientation.</p>



<h3 class="wp-block-heading" id="h-polarized-light-patterns">Polarized light patterns</h3>



<p>Birds can detect polarized light patterns in the sky, which are most prominent at sunrise and sunset. These patterns can help calibrate their internal compasses.</p>



<h3 class="wp-block-heading" id="h-landmarks">Landmarks</h3>



<p>For birds that fly at lower altitudes, physical landmarks like rivers, mountains, and coastlines can serve as guides.</p>



<h3 class="wp-block-heading" id="h-olfactory-cues">Olfactory cues</h3>



<p>Some research suggests that certain birds may also use olfactory cues - smelling their way along their migration routes.</p>



<p>The study is published in the journal <a href="http://dx.doi.org/10.1098/rspb.2023.2308" target="_blank" rel="noreferrer noopener"><em>Proceedings of the Royal Society B: Biological Sciences</em></a><em>.</em></p>



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How do migratory birds navigate with such accuracy?

A team of biologists led by the University of Oldenburg...

<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>



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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...

View,Of,The,Device,Of,An,Oil,Drilling,Rig

<p>Earth's surface bears the visible scars of human activities, from greenhouse gas emissions to deforestation. However, the impact of human intervention extends far beyond what meets the eye, reaching hundreds of meters to several kilometers beneath the <a href="https://www.earth.com/news/new-model-reveals-the-evolution-of-the-earths-surface/#google_vignette" target="_blank" rel="noreferrer noopener">planet's surface</a> into Earth's deep subsurface. </p>



<p>This hidden realm, often overlooked, is now the subject of disturbing research by hydrology experts. Jennifer McIntosh, a professor in the University of Arizona's <a href="https://has.arizona.edu/" target="_blank" rel="noreferrer noopener">Department of Hydrology and Atmospheric Sciences</a>, and her colleagues have delved into the ways humans influence Earth's deep subsurface. </p>



<p>"We looked at how the rates of fluid production with <a href="https://www.earth.com/news/oil-and-gas-production-linked-to-77-billion-in-annual-health-care-costs/" target="_blank" rel="noreferrer noopener">oil and gas</a> compare to natural background circulation of water and showed how humans have made a big impact on the circulation of fluids in the subsurface," McIntosh explained.</p>



<p>In a paper published in the journal <em>Earth's Future</em>, they shed light on the significant impact of human activities on the circulation of fluids in this subterranean zone.</p>



<h2 class="wp-block-heading">Deciphering the hidden world in motion beneath our feet</h2>



<p>The study, led by Grant Ferguson, also from the UArizona, compared the rates of fluid production from oil and gas extraction to the natural background circulation of water. </p>



<p>The findings reveal that human-induced <a href="https://www.earth.com/news/earth-internal-jet-stream-core/" target="_blank" rel="noreferrer noopener">fluid fluxes</a> surpass the natural flow, and they are projected to increase further with proposed strategies for combating climate change.</p>



<p>These strategies include geologic carbon sequestration, geothermal energy production, and <a href="https://www.earth.com/news/fools-gold-may-be-a-valuable-source-of-lithium/" target="_blank" rel="noreferrer noopener">lithium extraction</a> from underground mineral-rich brine. </p>



<p>"Responsible management of the subsurface is central to any hope for a green transition, sustainable future and keeping warming below a few degrees," emphasizes Peter Reiners, a professor in the <a href="https://www.geo.arizona.edu/" target="_blank" rel="noreferrer noopener">UArizona Department of Geosciences</a> and a co-author of the study.</p>



<h2 class="wp-block-heading" id="h-earth-s-subsurface-fluid-fluxes">Earth's subsurface fluid fluxes</h2>



<p>These fluxes transport water, gases, and other substances through the subsurface, influencing everything from groundwater resources to geothermal energy.</p>



<h3 class="wp-block-heading">Types of subsurface fluid fluxes</h3>



<h4 class="wp-block-heading">Groundwater flow</h4>



<p><a href="https://www.earth.com/news/groundwater-depletion-is-accelerating-but-it-is-not-inevitable/" target="_blank" rel="noreferrer noopener">Groundwater flow</a> represents the movement of water through porous and fractured rock formations. This flow occurs due to pressure gradients and the force of gravity, allowing water to move from areas of high hydraulic head to areas of low hydraulic head. Groundwater flow plays a vital role in the hydrologic cycle, recharging aquifers and sustaining surface water bodies.</p>



<h4 class="wp-block-heading">Hydrocarbon migration</h4>



<p>Subsurface fluid fluxes also include the migration of hydrocarbons, such as <a href="https://www.earth.com/news/millions-of-orphaned-oil-and-gas-wells-litter-the-world-and-must-be-cleaned-up/" target="_blank" rel="noreferrer noopener">oil and natural gas</a>. These fluids originate from organic-rich source rocks and migrate through permeable rock layers until they encounter traps or seals. Understanding hydrocarbon migration is essential for oil and gas exploration and production.</p>



<h4 class="wp-block-heading">Geothermal fluid circulation</h4>



<p>In regions with high <a href="https://www.earth.com/news/underground-water-could-be-a-great-source-of-renewable-energy/" target="_blank" rel="noreferrer noopener">geothermal gradients</a>, subsurface fluids can circulate through fractures and permeable rock formations, absorbing heat from the <a href="https://www.earth.com/news/discovery-ancient-ocean-floor-surrounds-the-earths-core/" target="_blank" rel="noreferrer noopener">Earth's interior</a>. This heated fluid can then rise to the surface, creating hot springs, geysers, and fumaroles. Geothermal fluid circulation is a key factor in the development of geothermal energy resources.</p>



<h2 class="wp-block-heading">Importance of Earth's subsurface fluid fluxes</h2>



<p>Subsurface fluid fluxes have far-reaching impacts on various aspects of our planet. They influence the availability and quality of groundwater resources, which are essential for human consumption, agriculture, and industrial activities. </p>



<p>Additionally, these fluxes play a crucial role in the formation and distribution of mineral resources, such as ore deposits and petroleum accumulations.</p>



<p>Moreover, subsurface fluid fluxes contribute to the transport and cycling of chemical elements and compounds within the <a href="https://www.earth.com/news/unexpected-molten-rock-layer-discovered-under-earths-crust/" target="_blank" rel="noreferrer noopener">Earth's crust</a>. </p>



<p>This process has implications for geochemical cycles, rock-water interactions, and the evolution of subsurface environments.</p>



<h2 class="wp-block-heading">Human intervention in Earth's fluid dynamics</h2>



<p>In <a href="https://www.earth.com/news/un-chief-fossil-fuel-era-must-end-for-humanitys-survival/" target="_blank" rel="noreferrer noopener">oil and natural gas</a> production, saline water from the deep subsurface is extracted alongside the targeted resources. This ancient water, often millions of years old, acquires its salinity from the evaporation of ancient seawater or reactions with rocks and minerals. </p>



<p>To maintain reservoir pressures and enhance oil recovery, near-surface water is added to the extracted saline water, and the blended mixture is reinjected into the subsurface, creating a continuous cycle of fluid production and reinjection.</p>



<p>Similar processes occur in lithium extraction, geothermal energy production, and geologic carbon sequestration, where leftover saline water is reinjected into the underground. </p>



<p>"We show that the fluid injection rates or recharge rates from those oil and gas activities is greater than what naturally occurs," states McIntosh.</p>



<h2 class="wp-block-heading">Rewriting Earth's history through subsurface geology</h2>



<p>Using existing data from various sources, the research team found that current fluid movement rates induced by human activities surpass those that occurred before human intervention. </p>



<p>As carbon capture, sequestration, and lithium extraction intensify, the researchers also predicted how these activities might be recorded in Earth's geological record.</p>



<p>Moreover, human activities have the potential to alter not only the <a href="https://www.earth.com/image/the-geysers-the-worlds-largest-geothermal-field/" target="_blank" rel="noreferrer noopener">deep subsurface fluids</a> but also the microbes that inhabit those depths. </p>



<p>Fluid movements can modify <a href="https://www.earth.com/news/life-in-the-extreme-microbial-activity-discovered-in-old-faithful/" target="_blank" rel="noreferrer noopener">microbial environments</a> through changes in water chemistry or by introducing new microbial communities from Earth's surface to the underground. </p>



<p><a href="https://www.earth.com/news/water-fracking-surged/">Hydraulic fracturing</a>, for example, can trigger sudden blooms of microbial activity in previously dormant deep rock formations.</p>



<h2 class="wp-block-heading">Earth's subsurface is still mostly a mystery</h2>



<p>Despite the significance of these findings, many unknowns remain about Earth's deep subsurface and the extent of human impact on this hidden realm. </p>



<p>"We need to use the deep subsurface as part of the solution for the climate crisis," emphasizes McIntosh. "Yet, we know more about the <a href="https://www.earth.com/news/lake-sediments-found-in-jezero-crater-hint-at-past-life-on-mars/" target="_blank" rel="noreferrer noopener">surface of Mars</a> than we do about water, rocks and life deep beneath our feet."</p>



<p>Continued research and exploration of this enigmatic zone are crucial for understanding the full scope of human influence on our planet and developing <a href="https://www.earth.com/news/international-day-of-zero-waste-a-global-commitment-to-a-sustainable-future/" target="_blank" rel="noreferrer noopener">sustainable strategies</a> for addressing the climate crisis. </p>



<p>While we strive to mitigate the visible effects of human activities on Earth's surface, we must not overlook the hidden impact that extends deep into the subsurface.</p>



<h2 class="wp-block-heading" id="h-protecting-what-lies-beneath">Protecting what lies beneath</h2>



<p>As we continue to explore and utilize Earth's deep subsurface in our efforts to combat climate change, we must remain mindful of the hidden impact our actions have on this enigmatic realm. </p>



<p>By studying the fluid dynamics, <a href="https://www.earth.com/news/climate-change-increases-threat-antimicrobial-resistance/" target="_blank" rel="noreferrer noopener">microbial communities</a>, and geological record beneath our feet, we can develop a deeper understanding of the complex interplay between human activities and the subterranean world. </p>



<p>This knowledge will be crucial in guiding our strategies for a sustainable future, ensuring that our solutions do not create unforeseen consequences in the depths below. </p>



<p>As we navigate the challenges of the climate crisis, we must approach the subsurface with a spirit of curiosity, responsibility, and respect, recognizing that the key to our success may lie in the mysteries that await us in Earth's hidden depths.</p>



<p>The full study was published in the journal <em><a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024EF004496" target="_blank" rel="noreferrer noopener">Earth's Future</a></em>.</p>



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



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Human activities also greatly harm Earth’s subsurface, not just the landmass

Earth's surface bears the visible scars of human activities, from...

<p>Rivers are not just pathways for water; they are dynamic forces that reshape the landscapes they traverse. Meandering <a href="https://www.earth.com/news/scientists-look-to-mars-to-help-clarify-how-river-paths-change-over-time/" target="_blank" rel="noreferrer noopener">rivers</a> carve intricate patterns into the Earth as they journey from mountainous regions to the sea, forming valleys, canyons, floodplains, and deltas. </p>



<p>Researchers from <a href="https://www.ucsb.edu/" target="_blank" rel="noreferrer noopener">UC Santa Barbara</a> have delved into the factors that influence how meandering rivers migrate across landscapes. The findings challenge some established theories and provide new insights into river behavior.</p>



<h2 class="wp-block-heading">Focus of the study</h2>



<p>“Meandering rivers move gradually across the floodplains, and this river movement presents socioeconomic risks along river corridors and regulates terrestrial biogeochemical cycles. Experimental and field studies suggest that fluvial sediment supply can exert a primary control on lateral migration rates of rivers,” wrote the researchers.</p>



<p>“However, we lack an understanding of the relative importance of environmental boundary conditions, such as floodplain vegetation and sediment supply, in setting the pace of river meandering across different environmental settings.”</p>



<h2 class="wp-block-heading" id="h-the-forces-shaping-meandering-rivers">The forces shaping meandering rivers</h2>



<p>The study was focused on two primary forces that affect the bends in meandering rivers: "bar push" and "bank pull."</p>



<p>Bar push occurs when sediment deposits inside a bend, pushing the river outward. Conversely, bank pull involves erosion on the opposite bank, which further exaggerates the bend. </p>



<p>Interestingly, the research suggests that sediment load - the amount of debris and minerals carried by rivers - plays a more significant role in this outward push than previously thought.</p>



<h2 class="wp-block-heading" id="h-global-trend-in-meandering-rivers">Global trend in meandering rivers </h2>



<p>Evan Greenberg, the lead researcher and a doctoral geography student, along with his advisor Professor Vamsi Ganti, compiled a comprehensive dataset covering 139 <a href="https://www.earth.com/video/the-lena-river-delta-from-space/" target="_blank" rel="noreferrer noopener">meandering</a> rivers worldwide. The team analyzed satellite imagery to observe how the paths of these rivers have shifted over time. </p>



<p>"We find a global-scale trend between the amount of sediment that rivers carry and how quickly they’re migrating, across all variables," explained Greenberg.</p>



<p>The analysis revealed that rivers laden with more sediment tend to migrate faster, a significant finding given that many of the world’s major waterways are meandering types. </p>



<p>These river migration patterns are crucial for effective environmental management and urban planning, especially as these waterways affect millions of people living in nearby floodplains.</p>



<h2 class="wp-block-heading" id="h-vegetation-s-role-in-stabilizing-rivers">Vegetation's role in stabilizing rivers</h2>



<p>Contrary to earlier studies that emphasized the stabilizing effects of vegetation, this new research shows that while vegetation does slow <a href="https://www.earth.com/news/river-profiles-climates/" target="_blank" rel="noreferrer noopener">river</a> migration, its impact is less significant than previously estimated.</p>



<p>Unvegetated rivers with higher sediment loads were found to migrate up to four times faster than those with similar dimensions but more vegetation.</p>



<h2 class="wp-block-heading" id="h-the-dynamics-of-meandering-river-patterns">The dynamics of meandering river patterns</h2>



<p>The interaction of bar push and bank pull creates the characteristic meandering pattern of these rivers. </p>



<p>"You can’t have one dominate the other in a meandering river," said Professor Ganti. He further noted the importance of a balanced interaction between these forces to prevent the transformation of meandering rivers into braided rivers, which can happen if the sediment supply is insufficient.</p>



<h2 class="wp-block-heading" id="h-dams-and-river-migration-a-unique-case-study">Dams and river migration: A unique case study</h2>



<p>The examination of rivers near <a href="https://www.earth.com/news/humans-have-caused-unprecedented-changes-to-rivers/">dams</a> provided an interesting case study within the research. Dams trap sediment but don't usually affect the vegetation, providing unique conditions to study how sediment load influences river migration. </p>



<p>The observations showed that downstream from dams, where rivers are sediment-starved, migration rates decrease notably.</p>



<h2 class="wp-block-heading" id="h-predicting-changes-and-managing-risks">Predicting changes and managing risks</h2>



<p>Looking ahead, the researchers plan to extend their analysis to more rivers and varied river types. The goal is to develop a model that predicts river migration through different landscapes, from their sources to their mouths. </p>



<p>This model could prove essential in predicting changes in river behavior due to environmental changes, such as sea-level rise, increased extreme weather events, and shifts in land use, which might lead to increased sediment loads.</p>



<p>In conclusion, understanding how meandering <a href="https://www.earth.com/news/international-day-of-action-for-rivers-lifelines-of-our-planet/" target="_blank" rel="noreferrer noopener">rivers</a> move is more than an academic pursuit— it's crucial for managing the risks associated with riverbank migration. </p>



<p>"More sediment means that rivers can do more stuff," said Professor Ganti, highlighting the dynamic and ever-changing nature of these fascinating systems. </p>



<p>This ongoing research into river dynamics will aid in the development of strategies to cope with future changes in these mighty rivers.</p>



<p>The study is published in the journal <em><a href="https://www.sciencedirect.com/science/article/pii/S0012821X24001079" target="_blank" rel="noreferrer noopener"><u>Earth and Planetary Science Letters</u></a></em>.</p>



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



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Study reveals new insights into the dynamics of meandering rivers

Rivers are not just pathways for water; they are dynamic...

Resistant,Bacteria,And,Superbug,Organism,Or,Mrsa,Medical,Healthcare,Concept

<p>The world is in trouble – have you ever considered that it's not just rising temperatures and natural disasters we need to worry about? <a href="https://www.earth.com/earthpedia-articles/climate-change/" target="_blank" rel="noreferrer noopener">Clima</a><a href="https://www.earth.com/news/survey-mother-nature-is-more-likely-to-solve-climate-change-than-geoengineering/" target="_blank" rel="noreferrer noopener">t</a><a href="https://www.earth.com/earthpedia-articles/climate-change/" target="_blank" rel="noreferrer noopener">e change</a> has a sinister accomplice: antimicrobial resistance (AMR), and together, they're a dangerous pair. </p>



<p>AMR refers to the increasingly worrisome trend of <a href="https://www.earth.com/news/beneficial-plant-bacteria-likely-to-decline-due-to-climate-change/" target="_blank" rel="noreferrer noopener">bacteria</a>, viruses, fungi, and parasites evolving to resist the very drugs designed to kill them.</p>



<h2 class="wp-block-heading" id="h-climate-change-drastic-impacts">Climate change drastic impacts</h2>



<p>Climate change is known as the threat multiplier for AMR. It has widespread effects that are making our superbug problem significantly worse. Here's how climate change is linked to antimicrobial resistance:</p>



<h3 class="wp-block-heading" id="h-a-warmer-world-means-more-illness">A warmer world means more illness</h3>



<p>Many disease-causing bacteria and other <a href="https://www.earth.com/news/can-soil-microbes-survive-climate-change/" target="_blank" rel="noreferrer noopener">microbes</a> have historically been limited by geography. Cooler temperatures prevented them from spreading extensively. Climate change disrupts these barriers. </p>



<p>Warmer temperatures allow these pathogens to survive further north or south of their original ranges, and at higher altitudes. </p>



<p>This means that diseases once confined to specific regions could emerge in new areas, posing risks to populations that may not have prior immunity or established medical protocols for treatment.</p>



<h3 class="wp-block-heading" id="h-stressed-ecosystems-breed-superbugs">Stressed ecosystems breed superbugs</h3>



<p>Disrupted water systems caused by <a href="https://www.earth.com/news/extreme-weather-has-increased-seasonal-insect-activity/" target="_blank" rel="noreferrer noopener">extreme weather</a> events, such as floods or droughts, can lead to contamination with sewage, agricultural runoff, or other sources carrying drug-resistant microbes. </p>



<p>This contaminated water can then spread these microbes to humans, animals, and crops, increasing the risk of infection and disease. </p>



<p>Additionally, changes in <a href="https://www.earth.com/news/cowspiracy-film-review/" target="_blank" rel="noreferrer noopener">animal agriculture</a> practices, often driven by the need to adapt to extreme weather, can lead to overcrowding or unsanitary conditions. </p>



<p>This creates a breeding ground for drug-resistant microbes to evolve and spread rapidly within animal populations.</p>



<h2 class="wp-block-heading" id="h-more-infections-more-antibiotics-more-resistance">More infections, more antibiotics, more resistance</h2>



<p><a href="https://www.earth.com/news/iss-climate-change/" target="_blank" rel="noreferrer noopener">Climate</a> change disrupts ecosystems and weather patterns, leading to several consequences that can increase the spread of diseases caused by various microbes. Warmer temperatures, for example, can allow microbes that thrive in warmer environments to expand their geographic range. </p>



<p>Additionally, extreme weather events like floods and droughts can disrupt water systems and sanitation infrastructure, creating ideal breeding grounds for microbes. These factors contribute to a rise in the number of infections and outbreaks of diseases.</p>



<p>The natural response to this increase in illnesses is often an increased reliance on antibiotics, powerful drugs that target and kill specific microbes. However, this increased use of antibiotics creates a selective pressure on the microbial populations. </p>



<p>As with any population under pressure, some microbes will develop adaptations that allow them to survive antibiotic exposure. These adaptations are the mechanisms of <a href="https://www.earth.com/news/antibiotic-resistance-increasing-enterococci-looming-global-crisis/" target="_blank" rel="noreferrer noopener">antibiotic resistance</a>.</p>



<h2 class="wp-block-heading" id="h-real-world-effects-of-climate-change-on-antimicrobial-resistance">Real-world effects of climate change on antimicrobial resistance</h2>



<p><a href="https://www.earth.com/news/global-temperature-increase-2023-blew-past-all-climate-models/" target="_blank" rel="noreferrer noopener">Climate</a> change is about subtle shifts at the microbial level that are already having serious impacts on our health. The examples below are a snapshot of what could become a widespread crisis.</p>



<h3 class="wp-block-heading" id="h-bacteria">Bacteria</h3>



<p>Bacteria like&nbsp;<em>Campylobacter</em>&nbsp;and&nbsp;<em>Salmonella</em>, responsible for a significant number of food poisoning cases, are flourishing in warming water. Water systems in homes, food processing, and the environment at large are becoming more hospitable.</p>



<p>Contaminated water means these bacteria spread more easily. They can end up on fresh produce, in meat and poultry during processing, and even in drinking water. The warmer the water, the more these bacteria multiply, increasing our risk of getting sick.</p>



<h3 class="wp-block-heading" id="h-fungus">Fungus</h3>



<p><em>Candida auris</em>, previously not a major issue for humans, has emerged as a serious threat. One reason is its newfound ability to tolerate warmer and saltier conditions, likely an adaptation driven by the environment changing due to <a href="https://www.earth.com/news/understanding-the-impact-of-climate-change-at-the-national-level/" target="_blank" rel="noreferrer noopener">climate</a> change.</p>



<p>This fungus is highly drug-resistant and can cause severe infections, particularly in already-sick patients. As the world warms and coastal areas change, this fungus could become much more common, posing risks to hospitals and people with weakened immune systems.</p>



<h3 class="wp-block-heading" id="h-world-threat">World threat</h3>



<p>Regions with rising average temperatures are also seeing more infections caused by antibiotic-resistant strains of&nbsp;<em>E.coli</em>. This correlation, if seen elsewhere in the world, would mean serious trouble. Infections that were once easy to treat may become a major health challenge.</p>



<p>“Climate change compromises the ecological and environmental integrity of living systems and enables pathogens to increasingly cause disease. The impact on water systems, food-producing animals and crops threatens global food supply," explained Professor Sabiha Essack, South African Research Chair in Antibiotic Resistance and One Health at the Antimicrobial Research Unit, <a href="https://ww3.ukzn.ac.za" target="_blank" rel="noreferrer noopener">University of KwaZulu-Natal</a>. </p>



<p>"Human activities associated with population growth and transport, together with climate change increases antibiotic resistance and the spread of waterborne and vector- borne diseases of humans, animals and plants,” Essack concluded.</p>



<h2 class="wp-block-heading" id="h-melting-ice-from-climate-change-drives-antimicrobial-resistance">Melting ice from climate change drives antimicrobial resistance</h2>



<p>Professor Essack's research raises a critical point: as our planet warms, sea levels are rising at unprecedented rates. This isn't just a threat to coastal communities; it also unlocks a hidden danger – the thawing of permafrost. </p>



<p>Permafrost is permanently frozen ground, mostly in the Arctic regions, that has been like a giant natural deep freezer for millennia.</p>



<p><a href="https://www.earth.com/news/time-traveling-pathogens-from-melting-permafrost-pose-great-risk-to-the-earth/" target="_blank" rel="noreferrer noopener">Melting permafrost</a> releases previously frozen soil, organic matter, and even trapped organisms. These organisms, including ancient microbes, have been entombed for vast stretches of time. </p>



<p>Some of these microbes may carry genes for antibiotic resistance, genes they never needed in their frozen state but which could now pose a serious threat.</p>



<p>The released microbes and their antibiotic resistance genes can <a href="https://www.earth.com/news/how-do-deadly-microbes-travel-around-the-world-so-quickly/" target="_blank" rel="noreferrer noopener">travel far and wide</a>. Ocean currents can carry them across vast distances, potentially introducing them to new ecosystems. </p>



<p>Even ships can act as unintentional transporters, carrying microbes in ballast water (water taken on board to ensure stability) that is then released in different ports.</p>



<p>The emergence of antibiotic-resistant microbes from permafrost adds another layer of complexity to the already concerning issue of AMR. </p>



<p>These ancient microbes may have unique resistance mechanisms, posing new challenges for our existing antibiotics. This further emphasizes the need for international collaboration and research to address this evolving threat.</p>



<p>While rising sea levels grab headlines, the hidden consequences of permafrost thaw are a stark reminder of the interconnectedness of our planet. <a href="https://www.earth.com/news/38-trillion-dollars-per-year-economic-losses-expected-from-climate-change/" target="_blank" rel="noreferrer noopener">Climate</a> change disrupts these delicate natural systems, and the consequences can be far-reaching and long-lasting.</p>



<h2 class="wp-block-heading" id="h-halting-climate-change-and-antimicrobial-resistance">Halting climate change and antimicrobial resistance</h2>



<p>Climate change alone is bad enough, but how we respond to it exacerbates the AMR crisis. Population growth, increased travel, and shifts in agriculture in response to disasters lead to more disease transmission and inappropriate use of antibiotics.</p>



<p>"Climate change has facilitated movement and proliferation of AMR. To deal with this threat, we will need unequivocal political leadership and commitment; strong global and local policy frameworks and governance; evidence-based, innovative 'One Health' solutions, and implementation research to adapt successful interventions to country contexts," explains Prof Essack.</p>



<p>“These partnerships must include a wide range of societal interests that will suspend interests of individual sectors for the public good. Initiatives that aim to make progress in climate change or AMR should join forces and highlight each other to make clear their mutual benefits," she concluded.</p>



<p>It sounds dire, but it doesn't mean we're powerless. Calling on our leaders to prioritize climate action and support the "One Health" approach (which recognizes the interconnectedness of human, animal, and environmental health) are crucial steps.</p>



<p>Dealing with both climate change and antibiotic resistance isn't going to be easy, but it's time we all woke up to this interconnected threat. Understanding the problem is the first step toward finding those smart, innovative solutions we need.</p>



<p>The study is part of <em>ESCMID Global Congress (formerly ECCMID) Barcelona, 27-30 April</em>.</p>



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Climate change fuels the rise of global antimicrobial resistance

The world is in trouble – have you ever considered...

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



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



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



<p><em>Video/ Image Credit: ESA</em></p>



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



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

Nushagak Bay in southwest Alaska

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



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



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



<p><em>Video/ Image Credit: American Chemical Society&nbsp;</em></p>



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



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



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

Flu viruses are more flexible than expected

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



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



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



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



<p><em>Video/Image Credit: ESA&nbsp;</em></p>



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



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

Lake Trasimeno in Central Italy

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



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



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



<p><em>Video Credit: American Chemical Society&nbsp;</em></p>



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



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



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

Detecting mercury contamination with the tap of a finger

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



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



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



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



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



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



<p><em>Video/ Image Credit: European Space Agency&nbsp;</em></p>



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



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



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

Kainji Lake in north central Nigeria

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



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



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



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



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



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



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



<p><em>Video Credit: Amanda Nguyen/University of Illinois</em></p>



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



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



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

Designing crops that can beat the heat

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<p>That time — roughly 400 B.C. — is known as the Early Horizon period. And there are multiple areas around Chankillo that prove people did build impressive fortifications back then. It goes to show just how rife with conflict this part of Peru was. But something about Chankillo just didn’t add up&#8230; Photo Credit: Werner Forman/Universal Images Group/Getty Images</p>


Early Horizon

<p>Think about it. You’ve got large, solid walls surrounding three buildings. There are stone towers to one side. The site is also positioned on a ridge above the landscape. All of these things combined would make Chankillo pretty easy to defend against potential attacks. And at the time the towers were built, repelling enemies could have been a big consideration. Photo Credit:  IDARQ/UNESCO</p>