Tracking sea ice is ‘early warning system' for global heating - but US halt to data sharing will make it harder, scientists warn
Researchers around the globe were told last week the US Department of Defence will stop processing and providing the data, used in studies on the state of Arctic and Antarctic sea ice, at the end of this month.
Tracking the state of sea ice is crucial for scientists to understand how global heating is affecting the planet.
Sea ice reflects the sun's energy back out to space but, as long-term losses have been recorded, more of the planet's ocean is exposed to the sun's energy, causing more heating.
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The National Snow and Ice Data Center, based at the University of Colorado, maintains a Sea Ice Index used around the world to track in near real-time the extent of sea ice around the globe.
In two updates in the past week, the centre said the US government's Department of Defence, which owns the satellites that contain onboard instruments used to track sea ice, would stop 'processing and delivering' the data on 31 July.
Climate scientists have been warning that Trump administration cuts have targeted climate functions across government, and there has been fears the sea ice data could be targeted.
The news comes as new research, some of which relied on the data, found that record low amounts of sea ice around Antarctica in recent years had seen more icebergs splintering off the continent's ice shelves in a process scientists warned could push up global sea levels faster than current modelling has predicted.
Dr Alex Fraser, a co-author of the research at the Australian Antarctic Program Partnership (AAPP), said NSIDC's sea ice data was 'our number one heart rate monitor' for the state of the planet's ice.
'It's our early warning system and tells us if the patient is about to flatline. We need this data and now [the scientific community] will be forced to put together a record from a different instrument. We won't have that continued context that we have had previously.'
NSIDC has said it is working with alternative and higher-resolution instruments from a different satellite, but has warned that data may not be directly comparable with the current instruments.
Fraser said: 'We are seeing records now year on year in Antarctica, so from that perspective this could not have come at a worse time.'
The research, published in the journal PNAS Nexus, found a link between increasing numbers of icebergs calving from floating ice shelves and the loss of sea ice.
While the loss of sea ice does not directly raise sea levels, the research said it exposed more ice shelves to wave action, causing them to break apart and release icebergs faster.
Glaciologist Dr Sue Cook, also from AAPP, said 'like a cork in a bottle' those shelves help to slow down the advance of land-based ice that does raise sea levels if it breaks off into the ocean.
She said the higher rates of iceberg calving seen in Antarctica were not accounted for in calculations of how quickly the ice sheet might break apart and contribute global sea levels.
'If we shift to this state where summer sea ice is very low but we continue using models based on previous periods, then we will definitely underestimate how quickly Antarctica will contribute to sea level rise,' she said.
The study also outlined other knock-on effects from the record low sea ice levels in the Antarctic, including the loss of more seals and penguins if trends continued.
As many as 7,000 emperor penguin chicks died in late 2022 after the early break-up of the stable ice they used for shelter while they grow their waterproof plumage.
Guardian Australia has requested comment from NSIDC and the US Department of Defence.
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Medical News Today
an hour ago
- Medical News Today
Pick up the pace to live longer, new study suggests
Physical activity like walking is an important part of a healthy lifestyle. Research is ongoing regarding the benefits of physical activity in various populations. One study focusing on low-income and Black participants found that fast walking may decrease mortality risk by almost 20%.Physical activity is one thing that helps people stay healthy and reduce the risk of health problems as they grow guidelines from the Office of Disease Prevention and Health Promotion say that adults should get '150 to 300 minutes of moderate-intensity aerobic activity' each week, and this can include activities like brisk walking. A new study published in the American Journal of Preventive Medicine has explored the relationship between daily walking and mortality, primarily focusing on low-income and Black results of the study suggest that regular walking may help lower mortality risk. The most pronounced mortality reduction was related to fast walking. Even slow walking can bring heart benefitsThe researchers who conducted this study note that there is somewhat limited data focusing on low-income and low-income Black individuals when it comes to 'walking and other leisure-time physical activity.'For the study, they used data from the Southern Community Cohort Study, which includes participants from twelve southeastern states. About two-thirds of this cohort is Black, and over half of the cohort's participants made less than $15,000 a year when they enrolled in the study. For the current research, the main sample included 79,856 participants, who provided information on their daily walking habits, including speed and speed fell into two broad categories. Slow walking included things like walking at work and light exercise. Fast walking included things like brisk walking or climbing the time, participants were divided into categories based on ranges of walking time. Researchers also had data on things like smoking, alcohol intake, and leisure-time physical activity. Based on leisure-time physical activity, researchers divided participants into the three categories of 'inactive, fairly active, and active.'Researchers were able to consider the overall healthiness of participants' lifestyles, and they had data on death and major causes of death. The average follow-up time with participants was just under 17 years, and throughout this time, about 27,000 deaths occurred. The greatest number of deaths, around 13,500, were from cardiovascular disease. About 48% of participants did not report fast walking, and about one-third walked slowly for more than 3 hours each day. For participants in this slow-walking category, there was 4% decreased mortality risk, but this was not statistically researchers did find that slow walking for over an hour each day could lower mortality related to all cardiovascular diseases, though the strongest association was with a lower risk of death from ischemic heart disease. Boosting walking pace just a little may prolong longevityFast walking appeared to offer the most benefit, with almost a 20% decrease in mortality associated with 15 minutes of fast walking daily. After adjusting for lifestyle factors, the association between mortality and slow and fast walking became less. However, the association for fast walking was still highly significant. Sensitivity analyses revealed that fast walking appeared to most reduce risk for death from cardiovascular disease, particularly cardiovascular disease death caused by heart main finding of stratified analyses was that the association between fast walking and lower mortality appeared to be stronger for participants who did not smoke and those with higher income. They note that they did not observe significant variations for body mass index, comorbidities, or participants who engaged in slow walking, doing more fast walking helped to further decrease mortality risk. Finally, researchers found that the association between fast walking and lower mortality was not dependent upon participants' leisure-time physical activity. For participants doing any leisure-time activity, longer amounts of fast walking led to more benefits. Does brisk walking pace boost health or is it dictated by fitness?This research primarily focused on low-income and Black individuals, so more research can confirm similar findings in other groups, and the results may not be generalizable to other some data, like information on daily walking and lifestyle, came from participant reporting, and some of this data might not be acknowledge that some participants' walking reports could have included 'other types of physical activity' like climbing stairs, so misclassification is possible. Since they only looked at physical activity at baseline, they were not able to assess changes that could have happened in physical activity and how this could have affected outcomes. Researchers acknowledge risk for residual confounding and reverse causation. They suggest that future research can also see how factors like psychosocial stressors and material well-being play into fast walking and mortality risk. Finally, sensitivity analyses included participants who had missing data on walking and participants 'who died within the first 2 years.' The timing of death could introduce possible bias. Cardiologist Patrick Kee, MD, PhD, Vital Heart & Vein in Houston, who was not involved in the study, noted the following cautions when it comes to this research speaking to Medical News Today:'The ability to walk briskly may primarily serve as a proxy for overall physical fitness and the absence of severe comorbidities rather than an independent driver of improved outcomes. Individuals with obesity, frailty, advanced heart failure, chronic lung disease, a history of stroke with hemiplegia, or significant musculoskeletal issues may be underrepresented, and the self-reported nature of walking data further constrains the validity of the conclusions. Notably, the study does not establish causation nor does it validate brisk walking as an effective intervention to reduce cardiovascular mortality.''Brisk walking may primarily function as a marker of physical fitness and functional capacity rather than an independent health intervention,' Kee added.'There is a dose effect to walking'Overall, this study emphasizes the benefits of regular fast walking, which can help with informing recommendations. Kanwar Kelley, MD, JD, a triple board-certified in Otolaryngology Head & Neck Surgery (ENT), Obesity Medicine, and Lifestyle Medicine, and cofounder and CEO of Side Health in Orinda, CA, who was similarly not involved in the study, noted the following regarding the clinical implications to MNT: 'By recognizing that there is a dose effect to walking, recommendations can be better tailored to get the most effect from the intervention. Recognizing that there may be a difference between slow-walking and fast-walking, especially in specific populations, can have a similar effect to personalized medicine by recommending physical activities that may offer the most benefit to a particular patient.''While evidence suggests that walking in general can improve outcomes, the evidence in this paper can refine that recommendation and be more effective at setting goals. While not every individual can immediately engage in fast walking, using evidence such as that provided in this paper gives medical practitioners and physicians more leverage to help patients achieve a specific goal,' said David Cutler, MD, board-certified family medicine physician at Providence Saint John's Health Center in Santa Monica, CA, also not involved in the research, told us that, 'the fact that this population is at the greatest risk of premature death due to their low socioeconomic and minority status offers great hope for improving health outcomes in these populations.''Traditional cardiovascular risk factors such as controlling blood pressure, lowering cholesterol, managing diabetes, and stopping smoking need to be supplemented with the evidence-based science that strenuous exercise like 15 minutes of fast walking daily can reduce your chance of dying prematurely,' Cutler advised.
Daily Mail
5 hours ago
- Daily Mail
Early-onset Alzheimer's disease linked to another neurological condition suffered by 8million Americans
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Experts in Pennsylvania and Washington DC suggested the increased risk could be due to higher rates of other conditions in people with autism, like depression and diabetes, which have been shown to cause damaging inflammation in the brain. Drugs that block neurotransmitters responsible for memory like bladder drugs and Benadryl may also be to blame, one of the studies suggested. The emerging research comes as one in 31 children in the US now have autism, a staggering increase from about one in 150 in the early 2000s. Experts suspect the surge is due to doctors getting better at detecting the disorder and increased awareness. However, health secretary Robert F Kennedy Jr earlier this year announced a series of studies to hone in on 'environmental toxins' he believes are responsible, including pollution, ultra-processed foods and ultrasound scans. Dr Lindsay Shea, one of the study authors and director of the Policy and Analytics Center at Drexel University's AJ Drexel Autism Institute, said during a conference presentation: 'We see that autistic children have grown up to become mostly autistic adults and now older adults. 'The first generation of autistic adults are now in their 80s and 90s.' Dementia is also on the rise, with experts suspecting it could strike 14million Americans by 2060. In one study presented this week at the Alzheimer's Association International Conference, researchers pulled Medicare and Medicaid claim data from 2017 to 2019 of nearly 800,000 Americans ages 30 and over. Participants were split into four groups: autism, autism plus intellectual disability (fetal alcohol syndrome, for example) or intellectual disability. There were 60,087 people in the autism group, 101,748 with both autism and intellectual disability and 632,607 with only an intellectual disability. 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Another study from George Washington University looked at two samples of 210 independent and 500 dependent autistic adults who reported signs of cognitive decline like trouble recalling tasks or words, impaired judgment or changes in behavior. Caregivers also noted their dependent loved ones wandered at night, avoided initiating conversation and lost track of time. Independent participants were between 42 and 81 years old with an average age of 54. Autistic adults dependent on a caregiver were 18 to 68 years old with an average age of About 30 percent of independent autistic people had two or more signs of cognitive decline while 10 percent of dependent adults had caregivers report at least one sign of impairment. The most common cognitive decline indicators were less interest in activities, everyday thinking problems and judgment issues. Dr Gregory Wallace, study author and associate professor at George Washington University, said: 'That's very high given the average age.' 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The increased dementia risk also may be tied to chronic conditions like depression, diabetes and high blood pressure, which induce harmful inflammation in the brain and damage neurons responsible for memory. Dr Shea said: 'This is particularly noteworthy because all of these diagnoses are more prevalent in autism than they are in the general population. 'We know that autistic adults are often unemployed, often don't have community integration and have high rates of obesity.'
The Independent
6 hours ago
- The Independent
Krill catch in Antarctica soars to record following collapse of conservation deal
Trawling near Antarctica for krill — a crustacean central to the diet of whales and a critical buffer to global warming — has surged to a record and is fast approaching a never before reached seasonal catch limit that would trigger the unprecedented early closure of the remote fishery, The Associated Press has learned. The fishing boom follows the failure last year of the U.S., Russia, China and two dozen other governments to approve a new management plan that would have mandated spreading out the area in which krill can be caught and creating a California-sized reserve along the environmentally sensitive Antarctic Peninsula. In the first seven months of the 2024-25 season, krill fishing in Antarctica reached 518,568 tons, about 84% of the 620,000-ton limit that, once reached, will force the fishery to automatically close. In one hot spot, the catch through June 30 was nearly 60% higher than all of last year's haul, according to a report from the Commission for the Conservation of Antarctic Marine Living Resources, or CCAMLR, the international organization that manages the world's southernmost fishery. The report, which has not been publicly released and CCAMLR said contains confidential data, was shared with The AP by someone concerned about overfishing in Antarctica on the condition of anonymity because they were not authorized to release the information. 'The vast majority of the krill take is from an increasingly smaller area,' said Capt. Peter Hammarstedt, campaign director for conservation group Sea Shepherd Global, which this year made its third voyage to Antarctica to document the fishery. 'It's the equivalent of a hunter saying that they're only killing 1% of the U.S.' deer population but leaving out that all of the deer were shot in Rhode Island.' Threat from climate change, advances in fishing Krill is one of the most abundant marine species in the world, with an estimated biomass of 63 million metric tons. But advances in fishing, climate change and growing demand for krill's Omega-3 rich oil – for fishmeal, pet food and human dietary supplements — have increased pressure on the krill stocks. In the 2023-24 season, a fleet of 12 industrial trawlers from mostly Norway and China caught 498,350 tons of krill — until now the largest harvest since CCAMLR began collecting catch data in 1973. AP journalists traveled to the icy waters around Antarctica in 2023 and observed how factory ships trawl in close proximity to whales whose numbers are still recovering from a century of industrial culling that nearly drove them to extinction. Underscoring the competition between humans and whales, three humpback whales were found dead or seriously injured last year in the long, cylindrical nets deployed by the vessels to vacuum up the paper-clip sized crustacean. Officials have been negotiating for years a new management plan that would balance the growing market for krill with calls for greater protection of the Antarctic Peninsula, the continent's northernmost point and an area teeming with whales and, increasingly, tourists. Currently, less than 5% of the Southern Ocean is protected — well behind CCAMLR's target and a United Nations goal to preserve 30% of the world's oceans by 2030. But a tentative deal fell apart at last year's CCAMLR meeting over a last minute proposal by the United Kingdom and Australia for an even lower catch limit than the one agreed to during talks, AP reported last year. China, objecting to the persistent Western demands, then withdrew its support for the marine reserve and refused to renew the existing management system. 'The truth was it was the UK,' Matts Johansen, chief executive of Norway's Aker BioMarine, the world's largest supplier of krill-based products, said at the United Nations Oceans conference in June. 'Just a couple days before the vote, the UK threw another suggestion and that's when the Chinese backed off.' A spokesperson for the UK Foreign Office rejected that characterization and said the British government continues to push for a krill management strategy that better safeguards Antarctic marine species and vulnerable ecosystems. Catch limit restrictions expire In the absence of a deal, restrictions adopted 15 years ago to spread out the catch limit expired, allowing the krill fleet to essentially fish anywhere at any time, including in smaller habitats preferred by whales and other animals such as penguins and seals. Krill aren't just vital to marine ecosystems. Increasingly, researchers are focusing on their role as a bulwark against climate change. One peer-reviewed study last year found that krill remove from the atmosphere and store in the ocean 20 million tons of carbon annually. That's the equivalent of taking off the road 5 million cars every year. CCAMLR declined to comment on the report obtained by the AP. Ship tracking data analyzed by Global Fishing Watch at the request of the AP also showed a higher concentration of trawling. Activity in one popular fishing ground, denoted Sub-Area 48.1, appears to have more than doubled so far this season compared to the entire 2023-2024 season, according to the the U.S.-based group, which supports sustainable fishing. Javier Arata, the executive director the Association of Responsible Krill harvesting companies, whose members are responsible for 95% of the krill taken from Antarctica, said the catch limit that lapsed was always intended as an interim measure. His group supports the creation of marine protected areas in Antarctica. But it rejects waiting for a conservation deal to adopt 'ready-to-go measures' raising the quota, which he said can be much higher. 'The failure to advance management was political, not scientific,' he said. The current fishing levels, although higher than previous limits, remain sustainable and reflect the consensus recommendation of scientists before last year's deal fell apart, Arata added. — This story was supported by funding from the Walton Family Foundation. The AP is solely responsible for all content. __ Contact AP's global investigative team at Investigative@ or
