Latest news with #SchoolofEnvironment
ABC News
5 days ago
- Science
- ABC News
Queensland mining data informs better understanding of underground stresses
New research into the world's tectonic plate stress patterns has led to a better understanding of how the mining and construction industry affects what goes on beneath the Earth's surface. The latest World Stress Map, released this week, revealed new earthquake trigger data and information about how stress builds in the Earth's crust as a result of underground mining activity mapped in Queensland's Bowen Basin. Mojtaba Rajabi, from University of Queensland's (UQ) School of Environment, said the latest update to the map could help make underground mining and construction activities safer by providing better insights into the Earth's stress conditions. "Digging, drilling or injecting fluids in the wrong spot can tip the underground balance and induce a seismic event. "Understanding stress helps us prevent these man-made shakes." Through UQ's collaboration with Germany's GFZ Helmholtz Centre for Geosciences, the Earth's underground stress patterns have been mapped in more detail than ever before. Dr Rajabi said the latest update included more than 100,000 stress data records. "This is almost double the data from the previous release we published in 2016," he said. The new data from central Queensland's mining heartland, the Bowen Basin, has found a dramatic rotation in underground stress of more than 50 degrees within 100 kilometres. Dr Rajabi said the mining data, which was analysed remotely, would lead to pinpointing vulnerable areas that could potentially trigger earthquakes. "The direction of the tectonic force coming from the plates east of Australia change dramatically, and when these forces interact with local geological conditions they redirect stress in different ways," he said. "As a result, the safest directions for drilling and excavation can vary significantly between locations in the same region. "This gives us a really great guide on ways we can dig safer in terms of mining or reservoir analysis studies, such as in our gas exploration." The Queensland Mining and Energy Union said the new data would be a vital tool for researchers and industries working to ensure the safe use of the Earth's sub-surface. Mining health and safety representative Jason Hill said it had the potential to help coal mines with strata control — a method used to maintain the stability of the ground. "Strata control is a principal hazard and it has killed a lot of people over the years, so any data or research into the management of strata is very much welcome," he said. Mr Hill said he hoped mining operators would adopt the findings. "The most important thing now is the companies actually take a look at [the report] and use it to ensure that they are achieving an acceptable level of risk," he said. The World Stress Map has been updated every decade for more than 40 years, drawing on data from seismology centres, the energy and resources sector and civil engineering projects across the globe. Dr Rajabi said Australia's underground stress patterns were unlike any other continent. "Highly variable, full of twists and turns, and not aligned with the direction the continent is moving," he said. "With this [new] level of detail, we can now better understand how tectonic forces behave not just across regions but at the local scale too."
Hans India
08-07-2025
- Science
- Hans India
Lizard Island on Australia's Great Barrier Reef faces alarming coral loss following 2024 bleaching
Sydney: Lizard Island on Australia's Great Barrier Reef has suffered one of the world's worst coral die-offs, with 92 per cent of surveyed corals lost after the 2024 bleaching event, new research has revealed. Researchers used drone imagery to assess the Fourth Global Coral Bleaching Event in 2024 at Lizard Island, where 96 per cent of corals were bleached and mortality averaged 92 per cent, with some sites losing over 99 per cent of corals, according to a statement released recently by Australia's Griffith University. "This marks one of the highest coral mortality rates ever documented globally," said the study's lead researcher Vincent Raoult from Griffith University's School of Environment. Raoult described the mortality as "unprecedented," especially given that Lizard Island experienced less heat stress than other parts of the Great Barrier Reef. Drone technology enabled precise mapping of the widespread bleaching, said Jane Williamson from the Macquarie University in Sydney, also the study's senior author, who stressed the urgent need for climate action, warning that repeated heatwaves could irreversibly damage coral reefs, Xinhua news agency reported. Lizard Island's reefs remain fragile after years of repeated damage, such as bleaching, cyclones, and Crown-of-Thorns outbreaks, and scientists will monitor them through 2026 for signs of recovery, according to the study published in Coral Reefs, the journal of the International Coral Reef Society. "Prolonged heat stress throughout the Far Northern and Northern regions of the reef caused widespread bleaching," said the reef snapshot published by the Great Barrier Reef Marine Park Authority, Australian Institute of Marine Science and Commonwealth Scientific and Industrial Research Organization, earlier in April. Coral bleaching is a phenomenon that occurs when coral experiencing heat stress expel the symbiotic algae living in their tissue and turn completely white. Bleaching is not fatal in itself but bleached coral are more likely to starve and can take a decade or longer to recover.
Scoop
08-07-2025
- Science
- Scoop
Sea Ice Loss Linked To Salty Southern Ocean Surface
Warmer, saltier water from deep in the Southern Ocean has started rising to the surface, bringing up more carbon dioxide, a recent study shows. Fresher, cooler surface waters had helped sea ice expand for more than thirty years, but the new satellite data shows this reversed a decade ago, when the surface began getting saltier as Antarctic sea ice coverage dropped. Human activity is expected to cause fresher surface water that traps warmer and saltier layers below, so the reason for this change is unclear. The SMC asked experts to comment. Dr Melissa Bowen, Associate Professor of Oceanography, School of Environment, University of Auckland, comments: 'The increased salinity in the Southern Ocean is puzzling. Clearly changes in the ocean, ice and atmosphere are linked and have been underway for the last decade. These changes have global implications: the ocean around Antarctica is a hub for ocean circulation because the density of water is transformed here and it moves to different depths, taking heat and gases with it. These changes in the Southern Ocean, and our lack of understanding about why they are occurring, set off alarm bells about how well we can anticipate future climate.' Conflict of interest statement: 'No conflicts of interest. I receive research funding from the Antarctic Science Platform.' Professor Wolfgang Rack, glaciologist and Director of Gateway Antarctica, University of Canterbury, comments: 'Sea ice in the Southern Ocean was regarded for a long time as a climate paradox. Until around 2015. The best observed climate variable by satellite was increasing its size despite global warming and ice volume decreasing elsewhere. Although still unclear why this was the case, one theory claims increased melt of the Antarctic ice sheet freshened the surface water, which can then more easily freeze. Many scientists expected the trend to reverse at some point, but the rate of the current retreat is completely unexpected and mind boggling. 'Although the chain of processes remains unclear, this new study shows a significant increase in surface salinity, exactly starting at the time of sea ice loss. On the observed scale, this is best explained by the upwelling of warm and salty deep water. It prevents sea water from freezing, and once frozen it can melt the ice more easily from below. It is the classic example of a positive feedback process. Less sea ice results in more solar heating of surface water, which results in even less sea ice. 'The findings are based on relatively short observations of satellites and autonomous buoys. Still, the earth south of our capital Wellington is the most under-surveyed region globally. With 85% ocean, of which one quarter is covered once a year by sea ice, the reasons of the dramatic sea ice decline require more and urgent research. Only then we will know how this important piece of information fits in the greater puzzle, and how quickly we will see flow on effects for ecosystems and global climate.' No conflicts of interest. Associate Professor Natalie Robinson, Marine Physicist, Earth Sciences New Zealand, Associate Professor in Sea Ice Science and Oceanography, Victoria University of Wellington, and Director of the Antarctic Science Platform, comments: 'The Southern Ocean is a critical player in our global climate. Although it covers only 17% of the globe, it absorbs more than half of the additional heat, and ~2/5 of the excess carbon dioxide, that result from human activities. One of the main Southern Ocean processes that help with this climate stabilisation is the annual cycle of sea ice formation and decay: each winter the surface of the ocean freezes, creating dense, cold brine that sinks to the ocean floor. This flows away from Antarctica into all of the major ocean basins, controlling how heat, oxygen, and nutrients are distributed around the world. This is the 'heartbeat' of the global ocean. 'But sea ice is changing. The past 10 years have seen a precipitous decline in Antarctic sea ice, with the Ross Sea leading the change. This is a clear symptom of significant changes in both the atmosphere and ocean of the southern polar latitudes. Shifting currents, changes to stratification, increasing storminess, and warming of both ocean and atmosphere are all playing their part in a complex interplay. 'This study delves into one aspect, linking surface salt content (which determines density in very cold water) to enhanced deep mixing, and an increased ability to draw heat up from below. This makes the surface waters both warmer and saltier, and therefore less likely to freeze. 'We are moving into uncharted climate territory, and Antarctica is responding. What happens in Antarctica has implications for the entire globe, but here in New Zealand we are impacted by changes to Antarctic sea ice more directly than most. Early indications are that a warmer Southern Ocean, exacerbated by retreat of the sea ice edge, contributes to increased storminess for New Zealand. When combined with the steadily warming waters of New Zealand's Exclusive Economic Zone, we should expect to see more of the intense rainfall events we've experienced recently, since warmer air can hold more moisture. 'In order to secure a liveable future for ourselves and our children, it is imperative that we drastically reduce our reliance on fossil fuels. The stable climate that has allowed human civilization to develop and thrive is now threatened by our intense and continued greenhouse gas emissions. This is an issue of intergenerational equity which impacts every aspect of our lives.' No conflicts of interest. Professor Craig Stevens, Principal Scientist – Marine Physics, Earth Sciences New Zealand and Department of Physics, University of Auckland, comments: 'This study from the group at Southampton in the UK uses some new approaches to data to look at the implications for sea ice with the changing ocean salinity around Antarctica. These combined effects are hugely important for a range of planetary and ecosystem processes. 'One of the main themes of the paper is the evolution of the so-called Maud Rise polynya. This is a remarkable phenomenon that occurs in the Atlantic sector of the Southern Ocean where a patch of open water appears even in winter. The study really hammers home the point that the ocean is made up of layers that mix or don't mix depending on external conditions. 'So, while it's far away from Aotearoa New Zealand, this polynya still has a global impact as it enables water to rapidly mix from the surface down to the seabed and 'ventilates' the oceans. The polynyas in our sector operate differently but still create that ventilation. 'One of the exciting things about the paper is the inclusion of satellite detected estimates of surface salinity and how this gets combined with robotic subsurface data. We've still so much to learn and will need all the data we can gather if we are going to improve our understanding of future changes to the oceans around Antarctica and how they will affect the rest of the planet.' Conflict of interest statement: 'I'm funded by the MBIE Antarctic Science Platform and the Marsden Fund and am on the council of the NZ Association of Scientists. I was also a co-author with the lead author of this study on a major 2023 review of ocean changes around Antarctica – it had around 50 authors, so everyone in the community.' Associate Professor Inga Smith, sea ice physicist in the Department of Physics, University of Otago and Co-Director of He Kaupapa Hononga: Otago's Climate Change Research Network, comments: 'The extremely important short paper 'Rising surface salinity and declining sea ice' contains shocking results for those of us researching Antarctic sea ice: the surface ocean waters around Antarctica are getting saltier as well as warmer. In a warming world, fresher water from melting of land-based ice sheets and floating ice shelves would be expected to dominate at the ocean surface. 'In 2023, Antarctic sea ice in the winter did not reach out as far from the coast as it had previously, with an extent of only around 17 million square kilometres, compared to more like 18.5 million square kilometres normally. Summer sea ice extent had also been dropping since around 2015/2016 after years of relative stability, but the winter absence of sea ice in 2023 raised new levels of concern. 'The role of warmer waters in the decline of Antarctic sea ice had already been documented by Ariaan Purich and Edward Doddridge, using data from autonomous ocean instruments called 'Argo floats'. This new paper by Alessandro Silvano and colleagues combines salinity data from Argo floats with satellite-derived ocean salinity data to show that the waters around Antarctica were more salty as well as warmer when sea ice extent changed. 'In the Southern Ocean near Antarctica, the density of sea water depends more on its salinity than its temperature, with saltier waters usually remaining at depth. The paper by Silvano and his colleagues does not identify the processes leading to the appearance of this saltier and warmer water near the surface; the authors will no doubt explore this in a longer paper sometime soon. 'The authors point out how critical it is for satellite measurements and direct ocean monitoring to be funded and supported so that scientists can work out what is happening in the Southern Ocean near Antarctica. No matter which country is involved, monitoring is often hard to get funding for from government science agencies who prefer more immediately impactful results. This paper shows the value of long-term, international and national investments in monitoring programmes. Ahead of the upcoming coordinated international projects Antarctica InSync (2027-2030) and International Polar Year (2032-2033), the value of such international cooperation will only become more important.' Conflict of interest statement: 'I was not involved with the research. I have not published research papers with the lead author yet (we are working on a collaborative proposal), but I have published research papers with three of the co-authors.' Dr Ken Hughes, Senior Lecturer in Coastal Processes, University of Waikato, comments: 'Antarctic sea ice extent was stable, perhaps even increasing slightly over time, back when I first began research in 2012. We assumed back then that the ocean and big ice shelves buffered the Antarctic system in some way so that the warming climate was not wreaking havoc on the ice extent in the same way it was for the Arctic. 'Fast forward a decade. The security of Antarctic sea ice is no longer taken for granted. The science has shifted to identifying the causes of the decline in the past years. 'The most difficult question is will the decline continue? Although this new study finds clear trends over the 13 year period from 2011 to 2023, textbooks tend to recommend a minimum of 30 years to confirm a climate trend. But a best guess now is much better than waiting until 2040 to check the correct answer.' No conflicts of interest. Professor James Renwick, Professor of Physical Geography, Victoria University of Wellington, comments: 'The new paper provides more evidence of a major change in the way the southern oceans are working, following publications of changes in upper-ocean heat content and analyses of how the southern oceans respond to changes in overlying westerly winds. The research all suggests that climate change is really starting to be expressed throughout the southern oceans. 'The implications are very worrying. Antarctic sea ice extent will likely continue to trend downwards from here (with ups and downs from year to year). That will accelerate the melting of ice shelves and land-based ice, increasing the rate of sea level rise and pushing us closer to the irreversible loss of the West Antarctic ice sheet. It will also reduce the reflectivity of the planet, bringing more warming.' Conflict of interest statement: James Renwick is a climate scientist based at Victoria University of Wellington-Te Herenga Waka, an IPCC author and a Principal Investigator in the Antarctic Science Platform. He has received New Zealand government funding for climate change research from the Marsden Fund and MBIE Endeavour fund.
Scoop
21-05-2025
- General
- Scoop
Proposed Increase To Glyphosate Limits
Press Release – Science Media Centre The proposed amendments change or set maximum residue levels in food sold in NZ for 14 substances, including glyphosate. Glyphosate limits would increase for certain cereal and pea crops, to support existing use as a preharvest herbicide or … NZ Food Safety has proposed changing the residue limits allowed in food for several agricultural compounds. The proposed amendments change or set maximum residue levels in food sold in NZ for 14 substances, including glyphosate (used in Roundup herbicide). Glyphosate limits would increase for certain cereal and pea crops, to 'support existing use' as a preharvest herbicide or dessicant. Submissions on the proposal closed on Friday, and the proposed amendments may progress, be modified, or be withdrawn. The Science Media Centre asked experts to comment. Associate Professor Melanie Kah, School of Environment, University of Auckland, comments: 'NZ Food Safety recently proposed to amend the Maximum Residue Limit for a dozen pesticides. The one for glyphosate raised concerns probably because glyphosate is often taken as an example for toxic pesticides by the public, even though it is a substance with a relatively low toxicity compared to other pesticides. 'The Maximum Residue Limit for glyphosate is proposed to be raised from a default value (0.1 mg/kg) to 10 mg/kg, which is similar or lower compared to Australian and international limits. The change is proposed to reflect potential residues resulting from current uses of glyphosate as pre-harvest desiccant following Good Agricultural Practices (i.e. how the product should be used following label instructions). It does not mean farmers will aim to have that level on produce. Surveys generally indicate that levels of residues are lower than that. 'Rather than focusing on the Maximum Residue Limit value and glyphosate in particular, I would question the practice of using herbicides as pre-harvest desiccant to facilitate harvest, which is a practice that is banned in other parts of the world e.g. Europe, mainly due to concerns related to residues on grains and impact on environmental health.' No conflicts of interest. Professor John D. Potter, Centre for Public Health Research, Massey University, comments: 'Glyphosate is a herbicide that now accounts for about 25% of the world's biocide use. 'Glyphosate was identified in 2015 as a probable human carcinogen by the International Agency for Research on Cancer, the cancer research arm of WHO. It has since been shown, in animal experiments, to also cause changes in intestinal microbes and the structure and permeability (increasing leakiness) of the wall of the intestine as well as altering lipid metabolism. 'Further, as it disrupts these microbes, it is probably altering the structure, function, and balance of those that live in the soil, with knock-on effects on soil quality, crop-raising, etc. It has now been banned and restricted in many countries. 'It is widespread in food and in human blood worldwide. As a consequence, it is difficult to establish the full range of impacts on human health because there are almost no unexposed people to compare with those who are exposed. 'What is clear is that as 'acceptable' levels rise, spraying will result in increased exposure for those who apply this herbicide for a living and for those who live downwind from sprayed crops. 'The Precautionary Principle would suggest that it is up to glyphosate's advocates to prove its safety and, in the absence of such proof, to reduce or eliminate exposure. 'At the very least, Aotearoa's government can be asked why they would choose now, in face of the evidence, to reduce restrictions.' No conflicts of interest. Professor of Toxicology Ian Shaw, School of Physical & Chemical Sciences, University of Canterbury, comments: 'The government is proposing an increase in the Maximum Residue Level for the herbicide glyphosate (the active ingredient in Roundup) from the default level of 0.1 mg/kg to 10.0 mg/kg. 'Pesticide Maximum Residue Levels are determined by measuring the concentration in a crop that was treated with the pesticide under Good Agricultural Practice. Maximum Residue Levels are trading standards, not consumer safety measures. 'The Acceptable Daily Intake is a consumer safety standard. Estimating glyphosate intake at the proposed new MRL (for example in wheat) shows that the proposed limit is of little or no toxicological concern. For glyphosate, the Acceptable Daily Intake is based on long term effects in rats. 'The government is also revising the genetically modified organism legislation. This might result in the approval of GM glyphosate resistant (Roundup Ready) crops in New Zealand. 'The use of glyphosate on Roundup Ready crops means higher crop residues, which would necessitate a higher Maximum Residue Level to facilitate trade. The cynic in me wonders if the two proposed legislative changes are linked.'
Scoop
21-05-2025
- Health
- Scoop
Proposed Increase To Glyphosate Limits
NZ Food Safety has proposed changing the residue limits allowed in food for several agricultural compounds. The proposed amendments change or set maximum residue levels in food sold in NZ for 14 substances, including glyphosate (used in Roundup herbicide). Glyphosate limits would increase for certain cereal and pea crops, to 'support existing use' as a preharvest herbicide or dessicant. Submissions on the proposal closed on Friday, and the proposed amendments may progress, be modified, or be withdrawn. The Science Media Centre asked experts to comment. Associate Professor Melanie Kah, School of Environment, University of Auckland, comments: 'NZ Food Safety recently proposed to amend the Maximum Residue Limit for a dozen pesticides. The one for glyphosate raised concerns probably because glyphosate is often taken as an example for toxic pesticides by the public, even though it is a substance with a relatively low toxicity compared to other pesticides. 'The Maximum Residue Limit for glyphosate is proposed to be raised from a default value (0.1 mg/kg) to 10 mg/kg, which is similar or lower compared to Australian and international limits. The change is proposed to reflect potential residues resulting from current uses of glyphosate as pre-harvest desiccant following Good Agricultural Practices (i.e. how the product should be used following label instructions). It does not mean farmers will aim to have that level on produce. Surveys generally indicate that levels of residues are lower than that. 'Rather than focusing on the Maximum Residue Limit value and glyphosate in particular, I would question the practice of using herbicides as pre-harvest desiccant to facilitate harvest, which is a practice that is banned in other parts of the world e.g. Europe, mainly due to concerns related to residues on grains and impact on environmental health.' No conflicts of interest. Professor John D. Potter, Centre for Public Health Research, Massey University, comments: 'Glyphosate is a herbicide that now accounts for about 25% of the world's biocide use. 'Glyphosate was identified in 2015 as a probable human carcinogen by the International Agency for Research on Cancer, the cancer research arm of WHO. It has since been shown, in animal experiments, to also cause changes in intestinal microbes and the structure and permeability (increasing leakiness) of the wall of the intestine as well as altering lipid metabolism. 'Further, as it disrupts these microbes, it is probably altering the structure, function, and balance of those that live in the soil, with knock-on effects on soil quality, crop-raising, etc. It has now been banned and restricted in many countries. 'It is widespread in food and in human blood worldwide. As a consequence, it is difficult to establish the full range of impacts on human health because there are almost no unexposed people to compare with those who are exposed. 'What is clear is that as 'acceptable' levels rise, spraying will result in increased exposure for those who apply this herbicide for a living and for those who live downwind from sprayed crops. 'The Precautionary Principle would suggest that it is up to glyphosate's advocates to prove its safety and, in the absence of such proof, to reduce or eliminate exposure. 'At the very least, Aotearoa's government can be asked why they would choose now, in face of the evidence, to reduce restrictions.' No conflicts of interest. Professor of Toxicology Ian Shaw, School of Physical & Chemical Sciences, University of Canterbury, comments: 'The government is proposing an increase in the Maximum Residue Level for the herbicide glyphosate (the active ingredient in Roundup) from the default level of 0.1 mg/kg to 10.0 mg/kg. 'Pesticide Maximum Residue Levels are determined by measuring the concentration in a crop that was treated with the pesticide under Good Agricultural Practice. Maximum Residue Levels are trading standards, not consumer safety measures. 'The Acceptable Daily Intake is a consumer safety standard. Estimating glyphosate intake at the proposed new MRL (for example in wheat) shows that the proposed limit is of little or no toxicological concern. For glyphosate, the Acceptable Daily Intake is based on long term effects in rats. 'The government is also revising the genetically modified organism legislation. This might result in the approval of GM glyphosate resistant (Roundup Ready) crops in New Zealand. 'The use of glyphosate on Roundup Ready crops means higher crop residues, which would necessitate a higher Maximum Residue Level to facilitate trade. The cynic in me wonders if the two proposed legislative changes are linked.'
