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    Extinção de corais prevista como onda de calor marinho engolfa o Havaí

    Em 12 de setembro, Foto de 2019 mostra coral em branqueamento na Baía de Kahala'u em Kailua-Kona, Havaí. Apenas quatro anos depois que uma grande onda de calor marinho matou quase metade dos corais desta costa, pesquisadores federais estão prevendo que outra rodada de água quente causará alguns dos piores branqueamento de corais que a região já viu. (AP Photo / Caleb Jones)

    Na borda de um antigo fluxo de lava, onde rochas negras irregulares encontram o Pacífico, pequenas casas isoladas têm vista para as calmas águas azuis de Papa Bay, na Ilha Grande do Havaí - sem turistas ou hotéis à vista. Aqui, um dos recifes de coral mais abundantes e vibrantes das ilhas prospera logo abaixo da superfície.

    No entanto, mesmo esta linha costeira remota, longe dos impactos do filtro solar químico, pisotear e esgoto industrial está mostrando os primeiros sinais do que se espera ser uma temporada catastrófica para os corais no Havaí.

    Apenas quatro anos depois que uma grande onda de calor marinho matou quase metade dos corais desta costa, pesquisadores federais estão prevendo que outra rodada de água quente causará alguns dos piores branqueamento de corais que a região já experimentou.

    “Em 2015, atingimos temperaturas que nunca registramos no Havaí, "disse Jamison Gove, oceanógrafo da Administração Oceânica e Atmosférica Nacional. "O que é realmente importante - ou alarmante, provavelmente mais apropriadamente — sobre este evento é que estivemos rastreando acima de onde estávamos neste momento em 2015. "

    Os pesquisadores que usam equipamentos de alta tecnologia para monitorar os recifes do Havaí estão vendo os primeiros sinais de branqueamento em Papa Bay e em outros lugares, causado por uma onda de calor marinho que elevou as temperaturas a níveis recordes por meses. Junho, Julho e partes de agosto experimentaram as temperaturas mais altas do oceano já registradas ao redor das ilhas havaianas. Até agora, em setembro, as temperaturas oceânicas estão abaixo apenas das observadas em 2015.

    Em 12 de setembro, A foto de 2019 mostra peixes perto de corais em uma baía na costa oeste da Ilha Grande, perto do Capitão Cook, Havaí. Apenas quatro anos depois que uma grande onda de calor marinho matou quase metade dos corais desta costa, pesquisadores federais estão prevendo que outra rodada de água quente causará alguns dos piores branqueamento de corais que a região já viu. (AP Photo / Brian Skoloff)

    Os meteorologistas preveem que as altas temperaturas no Pacífico Norte continuarão a bombear calor nas águas do Havaí até outubro.

    "As temperaturas estão altas há muito tempo, "Gove disse." Não é só o quão quente está. É quanto tempo as temperaturas do oceano permanecem quentes. "

    Os recifes de coral são vitais em todo o mundo, pois não apenas fornecem um habitat para peixes - a base da cadeia alimentar marinha - mas também alimentos e remédios para humanos. Eles também criam uma barreira costeira essencial que rompe as grandes ondas do oceano e protege as costas densamente povoadas das tempestades durante os furacões.

    No Havaí, os recifes também são uma parte importante da economia:o turismo prospera em grande parte por causa dos recifes de coral que ajudam a criar e proteger praias icônicas de areia branca, oferecem locais para mergulho e snorkel, e ajudam a formar ondas que atraem surfistas de todo o mundo.

    Em 12 de setembro, Foto de 2019 mostra coral em branqueamento na Baía de Kahala'u em Kailua-Kona, Havaí. Apenas quatro anos depois que uma grande onda de calor marinho matou quase metade dos corais desta costa, pesquisadores federais estão prevendo que outra rodada de água quente causará alguns dos piores branqueamento de corais que a região já viu. (AP Photo / Caleb Jones)

    As temperaturas do oceano não são uniformemente quentes em todo o estado, Gove notou. Padrões de vento locais, correntes e até mesmo recursos em terra podem criar pontos quentes na água.

    "Você tem coisas como dois vulcões gigantes na Ilha Grande bloqueando os ventos alísios predominantes, "tornando a costa oeste da ilha, onde Papa Bay se senta, uma das partes mais quentes do estado, Gove disse. Ele disse que espera um branqueamento "severo" do coral nesses locais.

    "Isso é generalizado, 100% de branqueamento da maioria dos corais, "Disse Gove. E muitos desses corais ainda estão se recuperando do evento de branqueamento de 2015, o que significa que eles são mais suscetíveis ao estresse térmico.

    De acordo com a NOAA, as causas da onda de calor incluem um padrão climático de baixa pressão persistente entre o Havaí e o Alasca que enfraqueceu os ventos que, de outra forma, poderiam se misturar e resfriar as águas superficiais em grande parte do Pacífico Norte. O que está causando isso não está claro:pode refletir o movimento caótico usual da atmosfera, ou pode estar relacionado ao aquecimento dos oceanos e outros efeitos das mudanças climáticas causadas pelo homem.

    Neste 13 de setembro, Imagem de 2019 retirada de um vídeo fornecido pelo Centro para Descoberta Global e Ciência da Conservação da Universidade do Estado do Arizona, o ecologista Greg Asner mergulha em um recife de coral em Papa Bay perto do Capitão Cook, Havaí. "Quase todas as espécies que monitoramos apresentam pelo menos algum branqueamento, "Asner disse. (Greg Asner / Centro da Universidade Estadual do Arizona para a Descoberta Global e Ciência da Conservação via AP)

    Além deste evento, as temperaturas oceânicas continuarão a aumentar nos próximos anos, Gove disse. "There's no question that global climate change is contributing to what we're experiencing, " ele disse.

    For coral, hot water means stress, and prolonged stress kills these creatures and can leave reefs in shambles.

    Bleaching occurs when stressed corals release algae that provide them with vital nutrients. That algae also gives the coral its color, so when it's expelled, the coral turns white.

    Gove said researchers have a technological advantage for monitoring and gleaning insights into this year's bleaching, data that could help save reefs in the future.

    "We're trying to track this event in real time via satellite, which is the first time that's ever been done, " Gove said.

    In remote Papa Bay, most of the corals have recovered from the 2015 bleaching event, but scientists worry they won't fare as well this time.

    Neste 13 de setembro, 2019, image taken from video provided by Arizona State University's Center for Global Discovery and Conservation Science, ecologist Greg Asner prepares a camera fish trap on a coral reef in Papa Bay near Captain Cook, Havaí. "Nearly every species that we monitor has at least some bleaching, " Asner said. (Greg Asner/Arizona State University's Center for Global Discovery and Conservation Science via AP)

    "Nearly every species that we monitor has at least some bleaching, "disse o ecologista Greg Asner, director of Arizona State University's Center for Global Discovery and Conservation Science, after a dive in the bay earlier this month.

    Asner told The Associated Press that sensors showed the bay was about 3.5 degrees Fahrenheit above what is normal for this time of year.

    He uses advanced imaging technology mounted to aircrafts, dados de satélite, underwater sensors and information from the public to give state and federal researchers like Gove the information they need.

    "What's really important here is that we're taking these (underwater) measurements, connecting them to our aircraft data and then connecting them again to the satellite data, " Asner said. "That lets us scale up to see the big picture to get the truth about what's going on here."

    Neste 13 de setembro, 2019 image taken from video provided by Arizona State University's Center for Global Discovery and Conservation Science, ecologist Greg Asner dives over a coral reef in Papa Bay near Captain Cook, Havaí. "Nearly every species that we monitor has at least some bleaching, " Asner said. (Greg Asner/Arizona State University's Center for Global Discovery and Conservation Science via AP)

    Scientists will use the information to research, entre outras coisas, why some coral species are more resilient to thermal stress. Some of the latest research suggests slowly exposing coral to heat in labs can condition them to withstand hotter water in the future.

    "After the heat wave ends, we will have a good map with which to plan restoration efforts, " Asner said.

    Enquanto isso, Hawaii residents like Cindi Punihaole Kennedy are pitching in by volunteering to educate tourists. Punihaole Kennedy is director of the Kahalu'u Bay Education Center, a nonprofit created to help protect Kahalu'u Bay, a popular snorkeling spot near the Big Island's tourist center of Kailua-Kona.

    The bay and surrounding beach park welcome more than 400, 000 visitors a year, ela disse.

    "We share with them what to do and what not to do as they enter the bay, "disse ela." Por exemplo, avoid stepping on the corals or feeding the fish."

    • Neste 13 de setembro, 2019 image taken from video provided by Arizona State University's Center for Global Discovery and Conservation Science, ecologist Greg Asner dives over a coral reef in Papa Bay near Captain Cook, Havaí. "Nearly every species that we monitor has at least some bleaching, " Asner said. (Greg Asner/Arizona State University's Center for Global Discovery and Conservation Science via AP)

    • In this Sept. 12, Foto 2019, fish swim near bleaching coral in Kahala'u Bay in Kailua-Kona, Havaí. Just four years after a major marine heat wave killed nearly half of this coastline's coral, federal researchers are predicting another round of hot water will cause some of the worst coral bleaching the region has ever seen. (AP Photo / Caleb Jones)

    • In this Sept. 12, Foto 2019, sea urchins and fish are seen near bleaching coral in Kahala'u Bay in Kailua-Kona, Havaí. Just four years after a major marine heat wave killed nearly half of this coastline's coral, federal researchers are predicting another round of hot water will cause some of the worst coral bleaching the region has ever seen. (AP Photo / Caleb Jones)

    • In this Sept. 12, Foto 2019, fish swim near bleaching coral in Kahala'u Bay in Kailua-Kona, Havaí. Coral reefs are vital around the world as they not only provide a habitat for fish—the base of the marine food chain—but food and medicine for humans. They also create an essential shoreline barrier that breaks apart large ocean swells and protects densely populated shorelines from storm surges during hurricanes. (AP Photo / Caleb Jones)

    • In this Sept. 12, Foto 2019, visitors stand in Kahala'u Bay in Kailua-Kona, Havaí. Hawaii residents like Cindi Punihaole Kennedy are pitching in by volunteering to educate tourists. Punihaole Kennedy is director of the Kahalu'u Bay Education Center, a nonprofit created to help protect Kahalu'u Bay, a popular snorkeling spot near the Big Island's tourist center of Kailua-Kona. (AP Photo / Caleb Jones)

    • This Sept. 13, 2019 photo shows a chunk of bleached, dead coral shown on a wall near a bay on the west coast of the Big Island near Captain Cook, Havaí. Coral reefs are vital around the world as they not only provide a habitat for fish—the base of the marine food chain—but food and medicine for humans. They also create an essential shoreline barrier that breaks apart large ocean swells and protects densely populated shorelines from storm surges during hurricanes. (AP Photo / Caleb Jones)

    • Neste 13 de setembro, Foto 2019, researchers prepare to dive on a coral reef on the west coast of the Big Island near Captain Cook, Havaí. One of the state's most vibrant coral reefs thrives just below the surface in a bay on the west coast of Hawaii's Big Island. Aqui, on a remote shoreline far from the impacts of sunscreen and throngs of tourists, scientists see the early signs of what's expected to be a catastrophic season of coral bleaching in Hawaii. The ocean here is about three and a half degrees above normal for this time of year. Coral can recover from bleaching, but when it is exposed to heat over several years, the likelihood of survival decreases. (AP Photo / Caleb Jones)

    • In this Sept. 11, Foto 2019, a green sea turtle swims near coral in a bay on the west coast of the Big Island near Captain Cook, Havaí. Just four years after a major marine heat wave killed nearly half of this coastline's coral, federal researchers are predicting another round of hot water will cause some of the worst coral bleaching the region has ever seen. (AP Photo/Brian Skoloff)

    • This Sept. 13, 2019 photo shows a chunk of bleached, dead coral shown on a wall near a bay on the west coast of the Big Island near Captain Cook, Havaí. One of the state's most vibrant coral reefs thrives just below the surface in a bay on the west coast of Hawaii's Big Island. Aqui, on a remote shoreline far from the impacts of sunscreen and throngs of tourists, scientists see the early signs of what's expected to be a catastrophic season of coral bleaching in Hawaii. The ocean here is about three and a half degrees above normal for this time of year. Coral can recover from bleaching, but when it is exposed to heat over several years, the likelihood of survival decreases. (AP Photo / Caleb Jones)

    • Neste 13 de setembro, Foto 2019, ecologist Greg Asner, the director of Arizona State University's Center for Global Discovery and Conservation Science, reviews ocean temperature data at his lab on the west coast of the Big Island near Captain Cook, Havaí. "Nearly every species that we monitor has at least some bleaching, " said Asner after a dive in Papa Bay. (AP Photo/Caleb Jones)

    • Neste dia 16 de setembro, Foto 2019, National Oceanic and Atmospheric Administration oceanographer Jamison Gove talks about coral bleaching at the NOAA regional office in Honolulu. U.S. federal researchers in Hawaii say ocean temperatures around the archipelago are on track to match or even surpass records set in 2015, the hottest year on record for the Pacific Ocean. They predict that heat will cause some of the worst coral bleaching and mortality the region has ever seen. (AP Photo / Caleb Jones)

    • Neste 13 de setembro, Foto 2019, ecologist Greg Asner, the director of Arizona State University's Center for Global Discovery and Conservation Science, reviews ocean temperature data at his lab on the west coast of the Big Island near Captain Cook, Havaí. "Nearly every species that we monitor has at least some bleaching, " said Asner after a dive in Papa Bay. (AP Photo/Caleb Jones)

    The bay suffered widespread bleaching and coral death in 2015.

    "It was devastating for us to not be able to do anything, " Punihaole Kennedy said. "We just watched the corals die."

    © 2019 Associated Press. Todos os direitos reservados.




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