July 22 will be the second-shortest day of the year, scientists say
The planet on Tuesday will experience a shorter rotation than the typical 24 hours, though not by much: 1.34 milliseconds less than usual, according to Timeanddate.com.
MORE: Climate change is altering the length of days on Earth, according to new research
Typically, we think of the shortest day in the Northern Hemisphere as Dec. 21 or 22, which coincides with the winter solstice – July 21 or 22 in the Southern Hemisphere – which is the point at which the hemisphere is tilted farthest away from the sun. In those instances, however, it's only the number of hours of daylight that are affected, and not the length of time it takes for the Earth to make a full rotation on its axis.
The 1.34-millisecond discrepancy in Tuesday's length is explained by differences in the gravitational pull between the Earth and the moon, which causes the Earth to spin more quickly, according to the Lunar and Planetary Institute.
In recent years, Earth has broken its own speed records several times, including on July 5, 2024 – the shortest day ever measured, when the planet's full rotation was completed 1.66 milliseconds faster than usual, according to Timeanddate.com.- PHOTO: Spinning Globe
This year, July 10 was measured as the shortest day of the year, with a full rotation occurring 1.36 milliseconds faster than normal. Aug. 5 is expected to be the third-shortest day of the year, projected to be 1.25 milliseconds shorter than usual.
Earth completes one full rotation on its axis in 24 hours, or about 86,400 seconds, plus or minus a millisecond or so, according to Timeanddate.com. Before 2020, Earth's shortest length of day was just 1.05 milliseconds shorter than usual.
MORE: What to know about the winter solstice, the shortest day of the year
If current trends continue, a full second may need to be subtracted from atomic clocks in the near future to accommodate for a "negative leap second," according to Timeanddate.com.
The system of leap seconds was introduced in the 1970s, according to Time and Date. While there have been dozens of positive leap seconds, in which a second was added, there has never been a negative leap second. The International Earth Rotation and Reference Systems Service, which monitor's the Earth's rotation, also determines whether to add or subtract a second.
In its early days – about 4.5 billion years ago – Earth was spinning at a much faster rate, according to the Lunar and Planetary Institute. A full rotation only lasted between three and six hours.
MORE: Melting polar ice is changing the Earth's rotation and affecting how we measure time: Study
During the mid-Proterozoic period – between 2.5 billion years ago and 543 million years ago – the Earth had slowed such that a day lasted about 19 hours, according to a 2023 study published in Nature Geoscience.
Since then, the length of an Earth day has slowed to its present 24 hours due to the fact that the moon's gravitational pull "steals" some of energy Earth uses to spin, in addition to causing tidal friction, according to the Institute.
Additionally, climate change is causing days on Earth to become longer due to the melting of ice at the poles, according to a study published in the Proceedings of the National Academy of Sciences. As the poles melt, the redistribution of mass from the resulting sea-level rise also is increasing the length of a day, the researchers found.
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Yahoo
6 hours ago
- Yahoo
Toxic algae are turning South Australia's coral reefs into underwater graveyards – and there's no end in sight
What struck Scott Bennett most were the razor clams. The long saltwater clams, resembling old-fashioned razors, normally burrow into sand to avoid predators. But when Bennett, an ecologist, visited South Australia's Great Southern Reef last month, he saw thousands of them rotting on the sea floor. '100% of them were dead and wasting away on the bottom,' Bennett told CNN. Since March, a harmful algal bloom, fueled by a marine heat wave, has been choking South Australia's coastline, turning once-colorful ecosystems filled with thriving marine life into underwater graveyards. The bloom has killed about 15,000 animals from over 450 species, according to observations on the citizen science site iNaturalist. They include longfinned worm eels, surf crabs, warty prowfish, leafy seadragons, hairy mussels and common bottlenose dolphins. The algae have poisoned more than 4,500 square kilometers (1,737 square miles) of the state's waters – an area larger than Rhode Island – littering beaches with carcasses and ravaging an area known for its diversity. It's 'one of the worst marine disasters in living memory,' according to a report by the Biodiversity Council, an independent expert group founded by 11 Australian universities. The toxic algal bloom has devastated South Australia's fishing industry and repelled beachgoers, serving as a stark warning of what happens when climate change goes unchecked. Once a bloom begins, there is no way of stopping it. 'This shouldn't be treated as an isolated event,' Bennett said. 'This is symptomatic of climate driven impacts that we're seeing across Australia due to climate change.' A mysterious yellow foam It all started back in March, when dozens of surfers at beaches outside Gulf St Vincent, about an hour south of state capital Adelaide, reported experiencing a sore throat, dry cough and blurred vision after emerging from the sea. Shortly after, a mysterious yellow foam appeared in the surf. Then, dead marine animals started washing up. Scientists at the University of Technology Sydney soon confirmed the culprit: a buildup of a tiny planktonic algae called Karenia mikimotoi. And it was spreading. In early May, the government of Kangaroo Island, a popular eco-tourism destination, said the algal bloom had reached its coastline. A storm at the end of May pushed the algae down the coast into the Coorong lagoon. By July, it had reached the beaches of Adelaide. Diverse algae are essential to healthy marine ecosystems, converting carbon dioxide into oxygen and benefiting organisms all the way up the food chain, from sea sponges and crabs to whales. But too much of one specific type of algae can be toxic, causing a harmful algal bloom, also sometimes known as a red tide. While Karenia mikimotoi does not cause long-term harm to humans, it can damage the gills of fish and shellfish, preventing them from breathing. Algal blooms can also cause discoloration in the water and block sunlight from coming in, harming ecosystems. The Great Southern Reef is a haven for 'really unique' biodiversity, said Bennett, a researcher at the University of Tasmania, who coined the name for the interconnected reef system which spans Australia's south coast. About 70% of the species that live there are endemic to the area, he said, meaning they are found nowhere else in the world. 'For these species, once they're gone, they're gone.' 'There is zero life' Nathan Eatts hasn't caught a single squid since April. On a good day, Eatts could catch 100 in the waters where he's fished commercially for 15 years off South Australia's Fleurieu Peninsula. Since the harmful algal bloom began, his business, Cape Calamari, has gone 'pretty much down to zero,' Eatts said. While more mobile fish can move to cleaner waters during an algal bloom, invertebrates like shellfish and sea stars, and other species associated with the reef, are suffocated by toxic algae. 'We don't know whether they've all died, or they're just seeking refuge in deeper water, waiting for it all to clear,' he said. Many fishers have lost their livelihoods overnight, with about a third of the state waters completely devoid of fish, according to Pat Tripodi, the executive officer of the Marine Fishers Association, which represents the interests of most commercial fishing license holders in the state. 'Wherever the algal bloom hits, there is zero life,' Tripodi said. 'It's a really high emotional and mental strain on these individuals, because many of them don't know how or if they will ever recover from it.' Beyond the fishers themselves, the bloom is having a knock-on effect on the state's seafood industry, which is valued at almost 480 million Australian dollars ($315 million). Seafood processors, transport companies, grocers and restaurants are all feeling the pain, Tripodi said. Eatts comes from a long line of fishers, and they've never seen anything like this. The last time a harmful agal bloom swept South Australia was in 2014, but it was much more localized. Toxic algal blooms are naturally occurring and are common around the world, including in the US. But climate change is making them more frequent and more severe. The foundation for the South Australian bloom was laid back in 2022, experts believe, when catastrophic flooding swept the Murray, Australia's longest river, washing extra nutrients into the Southern Ocean. The next summer, currents brought nutrient-rich water to the surface in a process called cold water upwelling. Then, a marine heatwave in September 2024 caused ocean temperatures to be about 2.5 degrees Celsius warmer than usual. That, combined with calm water conditions and light wind created conditions for the algae to grow and spread. A fire that can't be put out There is no way for humans to stop a harmful algal bloom – its trajectory largely depends on natural factors like wind and weather patterns. Peter Malinauskas, South Australia's premier, told public broadcaster the ABC on Tuesday that the crisis is a 'natural disaster, but it's different to ones that we're familiar with in Australia.' 'With a bushfire, you can put the fire out. If there's a flood, you can do the modeling to have a sense of where the water is going to go, whereas this is so entirely unprecedented. We don't really know how it's going to play out over coming weeks and months ahead.' This week, Prime Minister Anthony Albanese's government announced a support package of 14 million Australian dollars ($9.2 million), which has been matched by the state, to help with the cleanup and economic fallout from the ecological crisis. But Canberra stopped short of calling it a natural disaster, a declaration which would have unlocked additional funding. As extreme heat events become more common around the world, Bennett said the government needs to do more to prevent and protect against future algal blooms – first and foremost by cutting carbon emissions. Marine ecosystems can be 'resilient,' Bennett said. But he added that Australia must protect habitats, such as kelp forests, seagrass meadows, and oyster reefs, which absorb excess nutrients and keep the oceans healthy. Eatts, the calamari fisher, said it 'hits home hard' to see South Australia's natural beauty spoiled by this crisis. The other day, he saw a dead dolphin on his local beach. 'You take it for granted where you live and what you see on a daily basis,' he said. 'But it takes one event of nature like this to come through, and it breaks your heart watching it unfold.'
CNN
7 hours ago
- CNN
Toxic algae are turning South Australia's coral reefs into underwater graveyards – and there's no end in sight
What struck Scott Bennett most were the razor clams. The long saltwater clams, resembling old-fashioned razors, normally burrow into sand to avoid predators. But when Bennett, an ecologist, visited South Australia's Great Southern Reef last month, he saw thousands of them rotting on the sea floor. '100% of them were dead and wasting away on the bottom,' Bennett told CNN. Since March, a harmful algal bloom, fueled by a marine heat wave, has been choking South Australia's coastline, turning once-colorful ecosystems filled with thriving marine life into underwater graveyards. The bloom has killed about 15,000 animals from over 450 species, according to observations on the citizen science site iNaturalist. They include longfinned worm eels, surf crabs, warty prowfish, leafy seadragons, hairy mussels and common bottlenose dolphins. The algae have poisoned more than 4,500 square kilometers (1,737 square miles) of the state's waters – an area larger than Rhode Island – littering beaches with carcasses and ravaging an area known for its diversity. It's 'one of the worst marine disasters in living memory,' according to a report by the Biodiversity Council, an independent expert group founded by 11 Australian universities. The toxic algal bloom has devastated South Australia's fishing industry and repelled beachgoers, serving as a stark warning of what happens when climate change goes unchecked. Once a bloom begins, there is no way of stopping it. 'This shouldn't be treated as an isolated event,' Bennett said. 'This is symptomatic of climate driven impacts that we're seeing across Australia due to climate change.' It all started back in March, when dozens of surfers at beaches outside Gulf St Vincent, about an hour south of state capital Adelaide, reported experiencing a sore throat, dry cough and blurred vision after emerging from the sea. Shortly after, a mysterious yellow foam appeared in the surf. Then, dead marine animals started washing up. Scientists at the University of Technology Sydney soon confirmed the culprit: a buildup of a tiny planktonic algae called Karenia mikimotoi. And it was spreading. In early May, the government of Kangaroo Island, a popular eco-tourism destination, said the algal bloom had reached its coastline. A storm at the end of May pushed the algae down the coast into the Coorong lagoon. By July, it had reached the beaches of Adelaide. Diverse algae are essential to healthy marine ecosystems, converting carbon dioxide into oxygen and benefiting organisms all the way up the food chain, from sea sponges and crabs to whales. But too much of one specific type of algae can be toxic, causing a harmful algal bloom, also sometimes known as a red tide. While Karenia mikimotoi does not cause long-term harm to humans, it can damage the gills of fish and shellfish, preventing them from breathing. Algal blooms can also cause discoloration in the water and block sunlight from coming in, harming ecosystems. The Great Southern Reef is a haven for 'really unique' biodiversity, said Bennett, a researcher at the University of Tasmania, who coined the name for the interconnected reef system which spans Australia's south coast. About 70% of the species that live there are endemic to the area, he said, meaning they are found nowhere else in the world. 'For these species, once they're gone, they're gone.' Nathan Eatts hasn't caught a single squid since April. On a good day, Eatts could catch 100 in the waters where he's fished commercially for 15 years off South Australia's Fleurieu Peninsula. Since the harmful algal bloom began, his business, Cape Calamari, has gone 'pretty much down to zero,' Eatts said. While more mobile fish can move to cleaner waters during an algal bloom, invertebrates like shellfish and sea stars, and other species associated with the reef, are suffocated by toxic algae. 'We don't know whether they've all died, or they're just seeking refuge in deeper water, waiting for it all to clear,' he said. Many fishers have lost their livelihoods overnight, with about a third of the state waters completely devoid of fish, according to Pat Tripodi, the executive officer of the Marine Fishers Association, which represents the interests of most commercial fishing license holders in the state. 'Wherever the algal bloom hits, there is zero life,' Tripodi said. 'It's a really high emotional and mental strain on these individuals, because many of them don't know how or if they will ever recover from it.' Beyond the fishers themselves, the bloom is having a knock-on effect on the state's seafood industry, which is valued at almost 480 million Australian dollars ($315 million). Seafood processors, transport companies, grocers and restaurants are all feeling the pain, Tripodi said. Eatts comes from a long line of fishers, and they've never seen anything like this. The last time a harmful agal bloom swept South Australia was in 2014, but it was much more localized. Toxic algal blooms are naturally occurring and are common around the world, including in the US. But climate change is making them more frequent and more severe. The foundation for the South Australian bloom was laid back in 2022, experts believe, when catastrophic flooding swept the Murray, Australia's longest river, washing extra nutrients into the Southern Ocean. The next summer, currents brought nutrient-rich water to the surface in a process called cold water upwelling. Then, a marine heatwave in September 2024 caused ocean temperatures to be about 2.5 degrees Celsius warmer than usual. That, combined with calm water conditions and light wind created conditions for the algae to grow and spread. There is no way for humans to stop a harmful algal bloom – its trajectory largely depends on natural factors like wind and weather patterns. Peter Malinauskas, South Australia's premier, told public broadcaster the ABC on Tuesday that the crisis is a 'natural disaster, but it's different to ones that we're familiar with in Australia.' 'With a bushfire, you can put the fire out. If there's a flood, you can do the modeling to have a sense of where the water is going to go, whereas this is so entirely unprecedented. We don't really know how it's going to play out over coming weeks and months ahead.' This week, Prime Minister Anthony Albanese's government announced a support package of 14 million Australian dollars ($9.2 million), which has been matched by the state, to help with the cleanup and economic fallout from the ecological crisis. But Canberra stopped short of calling it a natural disaster, a declaration which would have unlocked additional funding. As extreme heat events become more common around the world, Bennett said the government needs to do more to prevent and protect against future algal blooms – first and foremost by cutting carbon emissions. Marine ecosystems can be 'resilient,' Bennett said. But he added that Australia must protect habitats, such as kelp forests, seagrass meadows, and oyster reefs, which absorb excess nutrients and keep the oceans healthy. Eatts, the calamari fisher, said it 'hits home hard' to see South Australia's natural beauty spoiled by this crisis. The other day, he saw a dead dolphin on his local beach. 'You take it for granted where you live and what you see on a daily basis,' he said. 'But it takes one event of nature like this to come through, and it breaks your heart watching it unfold.'
Yahoo
7 hours ago
- Yahoo
Research sheds light on bacteria outbreak that killed 1 person, several ABQ BioPark Zoo primates
ALBUQUERQUE, N.M. (KRQE) – A bacterial outbreak in Albuquerque between May 2021 and November 2023 that spread among people and primates from the ABQ BioPark Zoo, came from the same source, according to newly published research. The illness that plagued the community was determined to be shigella, a highly contagious gastrointestinal infection that is spread through the fecal-oral route and can be contracted by drinking contaminated food or water or coming into contact with someone who is sick or recently infected with shigellosis. Story continues below Education: APS Board members respond after vulgar text messages sent during board meeting New Mexico News Insiders: PFAS: The Most Contaminated Waters In New Mexico Trending: Albuquerque officials discuss moving historic diner to Route 66 Visitor Center The shigella outbreak left one person dead, and nearly 70% of people with the infection were hospitalized, according to the research article. The infection spread into the zoo, resulting in the death of six primates and leaving others infected. Upon learning of the outbreak, BioPark and NMDOH staff worked together to address the spread among both populations. Researchers were able to learn more about the outbreak, how it spread, and where it may have come from. The research team started by analyzing gene sequence samples from infected humans and primates. 'In looking at the genomes between human cases and the primate cases, we were able to see that in that there were zero differences. So there is no way that happens by chance. That means that they were the same strain of Shigella that was circulating in the zoo and in the human population,' said Sarah Shrum Davis, emerging infections program foodnet coordinator for the UNM Office of Community Health, and an NMDOH enteric team lead. Based on the data, Shrum Davis, and researchers were able to conclude the Shigella outbreak came from the same source, was introduced around February 2021, and possibly came from Texas. ' 'So bacteria evolve at a certain rate, and so Shigella evolves at a rate of about three mutations per year. We were able to look at the genetic sequences of our Shigella bacteria, and the closest strain that matched them did occur in Texas. And so by doing it by looking at the evolutionary rate of the bacteria, this is called a molecular clock, we were able to backtrace about when we think it was introduced into New Mexico,' she explained. According to Shrum Davis, cases of Shigella are reported year-round across the state of New Mexico. But what caught health officials' attention was the sharp uptick in cases in the Albuquerque area in both humans and primates around May 2021. NMDOH began investigating and alerted doctors that the strain was resistant to the first line of antibiotics that are used for treatment, and that they should potentially try and use other drugs to treat patients in this area. The City of Albuquerque also set up portable hand-washing stations to prevent the spread, Shrum Davis said. As for the ABQ BioPark, it had temporarily closed the Ape Walk while it provided medicine and care to its primates, including orangutans, siamangs, and gorillas. Unfortunately, some of the treatments did not work. 'I was disappointed and heartbroken when some of our animals were not getting better as quickly as I had hoped,' Carol Bradford, the senior veterinarian at the ABQ BioPark Zoo, said in an interview with UNM Health Sciences. 'Even though they were treated with appropriate antibiotics, the antibiotics didn't seem to make them feel better very quickly.' Bradford said there were 13 animals that were affected by the illness over the course of several weeks. 'What we do not think happened, and we want to be really clear about this, is that we don't think that there is any intentional exposure, and we don't think that, you know, anybody sort of had like contact with animals that they shouldn't have or anything like that. No keepers were sick,' said Shrum Davis. Researchers still do not know how the bacteria spread to the primates, but they do have a guess. 'Our leading hypotheses are that, you know, somebody who, you know, had the Shigella bacteria on their hands threw something into the primate areas and contaminated that way. We also do wonder about the potential of things like house flies bringing it in. Although the zoo does trap for flies, you know, at a certain point, there's only so much you can do,' Shrum Davis explained. The ABQ BioPark Zoo does have signs warning visitors not to throw food or other items into enclosures. To view the published research article, click here. Copyright 2025 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed. Solve the daily Crossword
