Subscriber CaaC (John)+ Posted May 16, 2020 Subscriber Posted May 16, 2020 Coral bleaching: Scientists 'find a way to make coral more heat-resistant' Scientists in Australia say they have found a way to help coral reefs fight the devastating effects of bleaching by making them more heat-resistant. Rising sea temperatures make corals expel tiny algae which live inside them. This turns the corals white and effectively starves them. In response, researchers have developed a lab-grown strain of microalgae which is more tolerant of heat. When injected back into the coral, the algae can handle warmer water better. What is coral bleaching and how bad is it? The researchers believe their findings may help in the effort to restore coral reefs, which they say are "suffering mass mortalities from marine heatwaves". The team made the coral - which is a type of animal, a marine invertebrate - more tolerant to temperature-induced bleaching by bolstering the heat tolerance of its microalgal symbionts - tiny cells of algae that live inside the coral tissue. They then exposed the cultured microalgae to increasingly warmer temperatures over a period of four years. This assisted them to adapt and survive hotter conditions. "Once the microalgae were reintroduced into coral larvae, the newly established coral-algal symbiosis was more heat-tolerant compared to the original one," lead author Dr Patrick Buerger, of Csiro, Australia's national science agency, said in a statement. "We found that the heat-tolerant microalgae are better at photosynthesis and improve the heat response of the coral animal," Prof Madeleine van Oppen, of the Australian Institute of Marine Science and the University of Melbourne, said. "These exciting findings show that the microalgae and the coral are in direct communication with each other." The next step is to further test the algal strains across a range of coral species. How bad is coral bleaching? "Coral reefs are in decline worldwide," Dr Buerger says. "Climate change has reduced coral cover, and surviving corals are under increasing pressure as water temperatures rise and the frequency and severity of coral bleaching events increase." Earlier this year, Australia's Great Barrier Reef suffered a mass bleaching event - the third in just five years. Warmer sea temperatures - particularly in February - are feared to have caused huge coral loss across it. Scientists say they have detected widespread bleaching, including extensive patches of severe damage. But they have also found healthy pockets. Two-thirds of the reef - the world's largest such system - were damaged by similar events in 2016 and 2017. You may also be interested in: https://www.bbc.co.uk/news/world-australia-52661860
Subscriber CaaC (John)+ Posted May 19, 2020 Subscriber Posted May 19, 2020 Climate change: Scientists fear car surge will see CO2 rebound Daily global emissions of CO2 fell by 17% at the peak of the shutdown because of measures taken by governments in response to Covid-19, say, scientists. The most comprehensive account yet published says that almost half the record decrease was due to fewer car journeys. But the authors are worried that, as people return to work, car use will soar again. They fear CO2 emissions could soon be higher than before the crisis. They are urging politicians to grasp the moment and make real, durable changes on transport and personal mobility. FULL REPORT
Subscriber CaaC (John)+ Posted May 24, 2020 Subscriber Posted May 24, 2020 Amazon under threat: fires, loggers and now virus The Amazon rainforest - which plays a vital role in balancing the world's climate and helping fight global warming - is also suffering as a result of the coronavirus pandemic. Deforestation jumped 55% in the first four months of 2020 compared with the same period last year, as people have taken advantage of the crisis to carry out illegal clearances. Deforestation, illegal mining, land clearances and wildfires were already at an 11-year high and scientists say we're fast approaching a point of no return - after which the Amazon will no longer function as it should. Here, we look at the pressures pushing the Amazon to the brink and ask what the nine countries that share this unique natural resource are doing to protect it. FULL REPORT
Subscriber CaaC (John)+ Posted May 29, 2020 Subscriber Posted May 29, 2020 Climate change: 'Stunning' seafloor ridges record Antarctic retreat Scientists are learning just how fast the ice margin of Antarctica can retreat in a warming world. They've identified features on the seafloor that indicate the ice edge was reversing at rates of up to 50m a day at the end of the last ice age. That's roughly 10 times faster than what's observed by satellites today. The discovery is important because it puts realistic constraints on the computer simulations that are used to project future change in the region. "In numerical models, you play with the parameters - and they can do very strange things," said Prof Julian Dowdeswell. "But what these data are saying is that actually rates considerably higher than we get even in the satellite record today were possible in the not-far-distant geological past." Thwaites: Journey to the 'doomsday glacier' Antarctic Peninsula 'can avoid irreversible change' Antarctica's 'green snow' mapped from space The director of the Scott Polar Research Institute (SPRI) in Cambridge, UK, led an expedition last year to the Larsen region of the Antarctic Peninsula. His team deployed autonomous underwater vehicles (AUVs) with high-resolution mapping capability to examine the sediments at the bottom of the western Weddell Sea. What the robots saw was a delicate pattern of ridges that looked like a series of ladders where each rung was about 1.5m high and spaced roughly 20-25m apart. The scientists interpret these ridges to be features that are generated at the ice grounding zone. The zone is the point where the ice flowing off Antarctica into the ocean becomes buoyant and starts to float. The rungs are created as the ice at this location repeatedly pats the sediments as the tides rise and fall. FULL REPORT
Subscriber CaaC (John)+ Posted June 21, 2020 Subscriber Posted June 21, 2020 One-fifth of Earth's ocean floor is now mapped We've just become a little less ignorant about Planet Earth. The initiative that seeks to galvanise the creation of a full map of the ocean floor says one-fifth of this task has now been completed. When the Nippon Foundation-GEBCO Seabed 2030 Project was launched in 2017, only 6% of the global ocean bottom had been surveyed to what might be called modern standards. That number now stands at 19%, up from 15% in just the last year. Some 14.5 million sq km of new bathymetric (depth) data was included in the GEBCO grid in 2019 - an area equivalent to almost twice that of Australia. It does, however, still leave a great swathe of the planet unmapped to an acceptable degree. "Today we stand at the 19% level. That means we've got another 81% of the oceans still to survey, still to map. That's an area about twice the size of Mars that we have to capture in the next decade," project director Jamie McMichael-Phillips told BBC News. FULL REPORT
Subscriber CaaC (John)+ Posted July 27, 2020 Subscriber Posted July 27, 2020 Climate change: Arctic heatwave temperatures reach possible all-time high Average temperatures in Siberia were 10°C above average last month. The UN weather agency warned that average temperatures in Siberia were 10°C above average last month, a spate of exceptional heat that has fanned devastating fires in the Arctic Circle and contributed to a rapid depletion in ice sea off Russia’s Arctic coast. “The Arctic is heating more than twice as fast as the global average, impacting local populations and ecosystems and with global repercussions,” World Meteorological Organisation (WMO) secretary-general Petteri Taalas said in a statement. He noted that Earth’s poles influence weather conditions far away, where hundreds of millions of people live. The WMO previously cited a reading of 38°C in the Russian town of Verkhoyansk on 20 June, which the agency has been seeking to verify as a possible record-high temperature in the Arctic Circle. It comes as fires have swept through the region, with satellite imagery showing the breadth of the area surface. The agency says the extended heat is linked to a large “blocking pressure system” and northward swing of the jet stream that has injected warm air into the region. But the WMO also pointed to a recent study by top climate scientists who found that such a rise in heat would have been nearly impossible without human-caused climate change. The WMO said information collected by the US National Snow and Ice Data Centre and the US National Ice Centre showed the Siberian heatwave had “accelerated the ice retreat along the Arctic Russian coast, in particular since late June, leading to very low sea ice extent in the Laptev and Barents Seas.” Science Focus
Subscriber CaaC (John)+ Posted July 31, 2020 Subscriber Posted July 31, 2020 European Sentinel satellites to map global CO2 emissions German manufacturer OHB-System has signed a €445m (£400m) contract to begin construction of a satellite network to monitor carbon dioxide. The CO2M constellation will consist in the first instance of two spacecraft, but there is an option for a third. The platforms will track the greenhouse gas across the globe, helping nations assess the scale of their emissions. Under the Paris climate accord, countries must compile CO2 inventories. CO2M will provide supporting data. The aim is to launch the OHB spacecraft in 2025 so they can inform the international stocktake that will report in 2028. FULL REPORT
Subscriber CaaC (John)+ Posted August 16, 2020 Subscriber Posted August 16, 2020 No way will they vanish...well, I hope not, cod & chips are one of my favourites. National favourite, cod and chips, at climate change risk Consumers may have to change their eating habits due to declining fish stocks, according to scientists. Popular dishes such as cod and chips could be under threat and disappear from British menus due to climate change, a study has warned. Researchers analysed its effects on stocks for south-west England’s fisheries and said families may have to change their diets to save the threatened species. The Celtic Sea, English Channel and the southern North Sea have experienced significant warming over the past 40 years, and further increases in sea temperatures are expected. Computer projections up to the year 2090 suggest increases in abundance of warm-adapted species such as red mullet, Dover sole, John Dory and lemon sole, and decreases in cold species such as cod, monkfish and megrim. The study, published in the Journal of Applied Ecology, involved the Universities of Exeter and Bristol, the Centre for Environment, Fisheries and Aquaculture Science (Cefas), and the Met Office. They said declining species may need help and there will be implications for the wider ecosystem. https://www.sciencefocus.com/news/national-favourite-cod-and-chips-at-climate-change-risk/
Subscriber CaaC (John)+ Posted September 16, 2020 Subscriber Posted September 16, 2020 Plug-in hybrids are a 'wolf in sheep's clothing' Carbon dioxide emissions from plug-in hybrid cars are as much as two-and-a-half times higher than official tests suggest, according to new research. Plug-in hybrid vehicles are powered by an electric motor using a battery that is recharged by being plugged in or via an on-board petrol or diesel engine. They account for 3% of new car sales. But analysis from pressure groups Transport and Environment and Greenpeace suggest they emit an average of 120g of CO2 per km. That compares with the 44g per km in official "lab" tests Plug-in hybrid electric vehicles (PHEVs) are sold as a low-carbon alternative to traditional vehicles and conventional hybrids - which cannot be recharged from an external source - and are proving increasingly popular. The new research is published as the government considers whether to bring forward a proposed ban on the sale of new petrol, diesel and conventional hybrid cars from 2035 to 2030. 'Official' versus 'real world' The BBC understands one suggestion is that plug-in hybrids should be given a stay of execution, with new sales allowed to continue until 2035. That's because they can offer a 20- to the 40-mile range as a purely electric vehicle and are therefore potentially significantly less polluting than other vehicles. But this new analysis from Transport and Environment and Greenpeace suggests they don't offer anything like the carbon dioxide savings claimed for them by manufacturers. The official tests indicate that plug-in hybrids emit an average of 44g per km of CO2. These tests are conducted on a circuit and see vehicles driven in a way that regulators consider "normal". The real figure, however, according to the report, is more like 120g per km. The pressure groups have analysed what they say is "real-world" data on fuel efficiency collected from some 20,000 plug-in hybrid drivers around Europe. These are drivers who have chosen to record their mileage and fuel consumption for surveys or who drive company or leased vehicles whose fuel efficiency is recorded. According to this data-set the lifetime emissions of a plug-in hybrid average around 28 tonnes of CO2. By comparison, the average petrol or diesel car is estimated to emit between 39 and 41 tonnes of CO2 from fuel during its lifetime, a conventional hybrid would typically emit more like 33 tonnes. According to these figures, a plug-in hybrid would only deliver an emissions reduction of about a third on a typical petrol or diesel car - far less than the official estimates. The motor industry acknowledges that lab tests don't always reflect real-world use but criticised the report, saying it uses emissions data from a test that is two years old. "PHEVs provide a flexibility few other technologies can yet match with extended range for longer, out-of-town journeys and battery power in urban areas, reducing emissions and improving city air quality," Mike Hawes, the chief executive of the Society of Motor Manufacturers and Traders told the BBC. He says he expects the range and performance will continue to improve, making them an "essential stepping stone to a fully electric vehicle". Greenpeace meanwhile describes PHEVs as "the car industry's wolf in sheep's clothing". "They may seem a much more environmentally friendly choice," says Rebecca Newsom, the pressure group's head of politics, "but false claims of lower emissions are a ploy by car manufacturers to go on producing SUVs and petrol and diesel engines." Driver behaviour Transport and Environment's analysis says a key problem with plug-in hybrids is that so many owners rarely actually charge their cars, meaning they rely on the petrol or diesel engine. Another is that many plug-in hybrid models include design features that automatically turn on the petrol/diesel engine at start-up on a cold day, or will kick in that engine if the driver accelerates hard. The latter mode means that the car's emissions will depend a lot on the driver's behaviour. "If you always charge the battery and tend to do lots of short journeys, they will have very low emissions," says Nick Molden, who runs Emissions Analytics, a company that specialises in vehicle emissions evaluation. "If you never charge the battery and drive very aggressively then they can have significantly higher emissions than the equivalent petrol or diesel model," he continues. https://www.bbc.co.uk/news/science-environment-54170207
Subscriber CaaC (John)+ Posted September 21, 2020 Subscriber Posted September 21, 2020 Satellite achieves sharp-eyed view of methane There is a powerful new satellite in the sky to monitor emissions of methane (CH4), one of the key gases driving human-induced climate change. Known as Iris, the spacecraft can map plumes of CH4 in the atmosphere down to a resolution of just 25m. This makes it possible to identify individual sources, such as specific oil and gas facilities. Iris was launched by the Montreal, Canada-based GHGSat company on 2 September. It's the pathfinder in what the firm hopes will be a 10-spacecraft constellation by the end of 2022. The image at the top of this page is Iris's "first light" - its first attempt to sense a significant emission of methane. The observation was made over Turkmenistan, in a region where large plumes from oil and gas infrastructure have been noted before. The detection, overlaid on a standard aerial image, shows the concentration of methane in the air in excess of normal background levels. "Let me tell you there was a big hurrah from the team when the data came down because we could see the spectroscopy was there, the resolution was there - everything was as it should be," recalled GHGSat CEO Stéphane Germain. "We still need to work on the calibration, which will then allow us to verify the detection threshold and the final performance of the satellite. But as a first-light image - by any standard it's phenomenal," he told BBC News. Methane's global warming potential is 30 times that of carbon dioxide, so it's imperative any unnecessary releases are constrained or curtailed. Human-produced sources are many and varied, including not only oil and gas facilities but agriculture, landfills, coal mines and hydro-electric dams. Already, GHGSat is working with operators, regulators and other interested parties to characterise these emissions using a prototype satellite called Claire that it launched in 2016. The presence in orbit of Iris provides an additional stream of data for the company that it now intends to interpret at a brand new British analytics hub, to be set up in Edinburgh and London in the coming weeks. "There's a world-class capability in what we do in the UK," Dr Germain said, "not only in analytics but also in the spacecraft systems that we're interested in. "The UK is a jurisdiction where climate change is important to people, and we want to be where people are willing to participate in the growth of an enterprise that wants to address that worldwide." GHGSat has recently been strengthening its ties with the European Space Agency, which operates the EU's Sentinel-5P satellite. This also monitors methane, taking a global daily snapshot of the gas. But at a resolution of 7km, its data is much less resolved than that of Iris, or indeed Claire which senses the atmosphere at scales of 50m. Put them all together, however, and they form something of a dream team for investigating CH4. "They (Sentinel-5P) can see the whole world every day. We can't do that. But we can see individual facilities. They can't do that. So, really, it's a fantastic combination, and it's making for a very good relationship with the European Space Agency that I think we're just at the beginning of growing into something much, much bigger." GHG's next satellite, Hugo, is in testing and is expected to launch at the end of this year. The company recently secured $30m (£23m) in extra financing, which enables it to build the three spacecraft that will follow Hugo into orbit. https://www.bbc.co.uk/news/science-environment-54210367
Carnivore Chris Posted September 21, 2020 Posted September 21, 2020 On 16/08/2020 at 12:54, CaaC (John) said: No way will they vanish...well, I hope not, cod & chips are one of my favourites. National favourite, cod and chips, at climate change risk Consumers may have to change their eating habits due to declining fish stocks, according to scientists. Popular dishes such as cod and chips could be under threat and disappear from British menus due to climate change, a study has warned. Researchers analysed its effects on stocks for south-west England’s fisheries and said families may have to change their diets to save the threatened species. The Celtic Sea, English Channel and the southern North Sea have experienced significant warming over the past 40 years, and further increases in sea temperatures are expected. Computer projections up to the year 2090 suggest increases in abundance of warm-adapted species such as red mullet, Dover sole, John Dory and lemon sole, and decreases in cold species such as cod, monkfish and megrim. The study, published in the Journal of Applied Ecology, involved the Universities of Exeter and Bristol, the Centre for Environment, Fisheries and Aquaculture Science (Cefas), and the Met Office. They said declining species may need help and there will be implications for the wider ecosystem. https://www.sciencefocus.com/news/national-favourite-cod-and-chips-at-climate-change-risk/ Haddock is my favourite, but it'll be under the same bracket as cod unfortunately and a fish that will be affected. Haddock is good for you as well(well maybe not when battered from the chippy..). It contains 60% of your daily vitamin B2 and contains about 30 grams of protein.
Subscriber CaaC (John)+ Posted September 21, 2020 Subscriber Posted September 21, 2020 27 minutes ago, Carnivore Chris said: Haddock is my favourite, but it'll be under the same bracket as cod unfortunately and a fish that will be affected. Haddock is good for you as well(well maybe not when battered from the chippy..). It contains 60% of your daily vitamin B2 and contains about 30 grams of protein I love my fish and another favourite is Rock Eel, it's very hard to get here in Scotland but when we lived in Southend-on-Sea, Essex, there was a chippy that did a beautiful battered Rock Eel, I practically lived on that with chips, a Friday night carry out for me and the wife in those days was a fish supper or Kentucky Fried Chicken.
Administrator Stan Posted September 21, 2020 Administrator Posted September 21, 2020 Haddock and chips is the bees knees for getting food from a chippy
Guest Posted October 7, 2020 Posted October 7, 2020 Anyone watched those David Attenborough documentaries. One on the BBC and one on netflix. Scary stuff
The Artful Dodger Posted October 7, 2020 Posted October 7, 2020 On 21/09/2020 at 19:34, Stan said: Haddock and chips is the bees knees for getting food from a chippy 100%. Haddock is so much nicer than cod, I’ll only eat Haddock in fact.
Bluewolf Posted October 7, 2020 Posted October 7, 2020 6 hours ago, Gunnersauraus said: Anyone watched those David Attenborough documentaries. One on the BBC and one on netflix. Scary stuff It's on my list...
Subscriber CaaC (John)+ Posted October 12, 2020 Subscriber Posted October 12, 2020 R.I.P. Mario Molina Quote Mario Molina, who warned of CFC threat to the ozone layer, dies Mario Molina, who was a joint recipient of the 1995 Nobel prize in chemistry, has died aged 77. In 1974, Molina and his then postdoctoral supervisor Frank Sherwood Rowland sounded the alarm over the role of common household chemicals in the destruction of the ozone layer. Their research showed how chlorofluorocarbons (CFCs) that were widely used in aerosol cans and refrigerators would dissociate when subjected to intense ultraviolet light in the stratosphere. This process generates chlorine atoms that catalyse ozone decomposition. Molina and Rowland calculated that unless CFC use drastically reduced, the ozone layer would be seriously damaged within decades. It was for this work that Molina and Rowland were awarded the Nobel prize alongside Paul Crutzen, who had revealed the role of nitrogen oxides in ozone depletion. Molina was born in Mexico City, Mexico, in 1943 and became interested in chemistry at an early age. After attending boarding school in Switzerland, he completed a bachelor’s degree in chemical engineering at the National Autonomous University of Mexico, before gaining his doctorate in physical chemistry at the University of California, Berkeley in 1972. Following his doctoral studies, Molina joined Rowland’s lab at the University of California, Irvine, where the pair would conduct their crucial investigations on CFCs. At first, their findings attracted scepticism and resistance, but further research supported their initial conclusions and paved the way for the signing of the Montreal Protocol – a major international commitment to phase out ozone-depleting substances that has been ratified by all 197 UN member states and is widely credited for helping to reverse the damage to the ozone layer. During his career, Molina held academic positions at the California Institute of Technology, the Massachusetts Institute of Technology and most recently at the University of California, San Diego (UCSD). Molina also dedicated much of his time to science policy, particularly in relation to climate change. He served as a scientific adviser to two US presidents, Bill Clinton and Barack Obama, and in 2004 he founded the Mario Molina Center in Mexico City, an environment-focused non-profit association. In April this year, he called for heads of state, global society and large businesses to collaborate on achieving the goals set out in the Paris Agreement. In a statement, UCSD’s chemistry department described Molina as ‘a true hero’ in the field of chemistry. ‘His Nobel prize-winning research on chlorofluorocarbons (CFCs) and his strong leadership showed how science can guide international agreements and policy. His research and teaching on climate change have inspired a new generation of scientists,’ it said. Molina passed away on 7 October 2020 following a heart attack. He is survived by his wife, Guadalupe Álvarez, and a son from his first marriage. https://www.chemistryworld.com/news/mario-molina-who-warned-of-cfc-threat-to-the-ozone-layer-dies/4012572.article
Subscriber CaaC (John)+ Posted October 22, 2020 Subscriber Posted October 22, 2020 Quote Australia urged to take in 3000 Pacific Islanders to offset climate change The Australian government is being urged to create a new visa for Pacific Islanders to relocate permanently to Australia, in a bid to manage the impact of climate change in the region. Tuvalu is highly susceptible to rises in sea level brought about by climate change. Photo: UNDP/LUKE MCPAKE The recommendation was outlined in a new policy paper released today by the University of New South Wales' Kaldor Centre for International Refugee Law. The paper urges the government to do more to help neighbouring countries, with several Pacific island nations facing an existential threat from rising sea levels. Co-author Jane McAdam said it was a roadmap for Australia to deal specifically with the displacement of Pacific Islanders as a result of climate change and natural disasters. "What we do know is that because disasters are likely to increase, both their intensity and their frequency, it means that people's normal adaptation capacity is being almost overtaken," she told the ABC's Pacific Beat programme. "Things are happening too quickly for them to be able to respond and avoid displacement altogether. The Carteret Islands were the first place in the world to require population relocations due to climate change, with predictions they would be submerged by 2015. "If you look at where the trajectory is unless you have major changes in mitigation and adaptation efforts, we're likely to see more displacement occurring." Co-author Jonathan Pryke, from the foreign affairs, think tank the Lowy Institute, told the ABC he recommended about 3000 permanent residencies for Pacific Islanders each year. He said relocating even a small number of people on a voluntary basis would help ease pressure on vulnerable countries. "We are advocating for a real drop in the ocean here with regards to our overall migration scheme," he said. "This is not a radical proposal, we're not suggesting opening the gates to the region. It's an important component of helping improve welfare in the region but also being an important mitigating tool for climate change displacement." FULL REPORT
Bluewolf Posted October 22, 2020 Posted October 22, 2020 These 2 photos were taken 21 years apart.. shows how much climate change has affected sea levels..
Subscriber CaaC (John)+ Posted November 22, 2020 Subscriber Posted November 22, 2020 Quote Sentinel-6: 'Dog kennel' satellite blasts off on ocean mission VIDEO A satellite that will be critical to the understanding of climate change has blasted skyward from California. Sentinel-6 "Michael Freilich" is set to become the primary means of measuring the shape of the world's oceans. Its data will track not only sea-level rise but reveal how the great mass of waters is moving around the globe. Looking somewhat like a dog kennel, the sophisticated 1.3-tonne satellite was taken aloft from the Vandenberg base on a SpaceX Falcon-9 rocket. The Sentinel is a joint endeavour between Europe and the US, and will continue the measurements that have been made by a succession of spacecraft, called the Jason-Topex/Poseidon series, going back to 1992. These earlier missions have shown unequivocally that sea levels globally are rising, at a rate in excess of 3mm per year over the 28-year period. And their most recent data even suggests there is an acceleration underway, with levels recorded as going up at over 4mm per year. FULL REPORT
Mpache Posted January 16, 2021 Posted January 16, 2021 Not going to lie, the weather here in Canada these past 2 years have been very concerning. Last year we only had 1 day go below -20, and this year we haven't had any -20 days yet. We were supposed to get a harsh winter and we haven't had that yet. Lakes don't freeze up like they used to either. The effects of climate change are evident. I checked other places in Canada. In Iqaluit which is near the arctic circle it will be more than -10 all week barring tomorrow. Grise Fiord is at -20 at the moment, which is honestly warm given they are in full darkness for the next 2 months and are the 2nd or 3rd most northern settlement in the world. Tromso in Norway is never that cold but it's not even below freezing. Not to mention all the glaciers melting especially in New Zealand. If you want to see glaciers, see them as soon as possible. Global warming is coming faster than we realize. The one bright side though is it's -46 in Oymyakon. Things are normal in Siberia still
Subscriber CaaC (John)+ Posted January 19, 2021 Subscriber Posted January 19, 2021 Quote Lessons from the past Could Indigenous wisdom help us create a “good Anthropocene”? The Anthropocene marks relentless and increasingly grave environmental degradation as the Earth faces tipping points for climate change, biodiversity and survival. To address these ills, scientists say we can learn valuable lessons from the past. “As our planet emerges into a new epoch in which humans dominate the Earth system, it is imperative that societies initiate a new phase of responsible environmental stewardship,” researchers write in the journal Nature Ecology & Evolution. “Maintenance of the Earth’s current ecological trajectory threatens not only countless other species but also critical ecosystem services that support human societies. “Here we argue that information from the past has a valuable role to play in enhancing the sustainability and resilience of our societies.” As well as learning from past mistakes, Nicole Boivin and Alison Crowther, both affiliated with Germany’s Max Planck Institute and the University of Queensland, stress how historical success stories can be integrated with contemporary solutions. In doing this, they say that archaeology, history and palaeoecology offer a vast resource that we should tap into to build on efforts to create a better future and a “good Anthropocene”. “We have at our fingertips a huge amount of information about how humans in the past have tried to solve many of the same problems we face today,” says Crowther. “Many of these solutions have been tried and tested over millennia; we know which ones worked and which ones failed, and why.” The review explores how historical data can be mined to improve biodiversity, conservation, fire management, carbon sequestration, soil sustainability, food security and agricultural sustainability, as well as mitigating pollution, building more sustainable cities and boosting resilience to climate change. For conservation, archaeology and palaeoecology offer insights into ecological baselines to understand how change occurred naturally before humans plundered onto the scene. “Work in restoration ecology requires an understanding of the degree of change that has occurred from baseline conditions, the natural, climate-driven shape of ecosystems prior to human intervention,” write Boivin and Crowther. In some instances, they note, past human activity added value to the planet, such as Canada’s Garry oak ecosystem, the formation of which has been attributed to indigenous peoples’ burning regime. “Accordingly, conservationists are increasingly embracing novel ecosystems and recognising that ecosystems created via long-term human management are equally valid targets for conservation.” Archaeology also tells us about past removal of species and successes or failures of efforts to reintroduce them, which can help us understand those species’ ranges and endemic status. In Australia and elsewhere, Indigenous and prehistoric fire-management practices are increasingly recognised by forest and land managers as effective ways to create fire-resilient communities and ecosystems – a burning issue with looming threats of longer, hotter dry spells and more intense fires. Agricultural practices also pose a major problem as “humans today control a vast and disproportionate share of the planet’s resources,” contributing to climate change, biodiversity and habitat loss and groundwater depletion. Modern agriculture destroys forests and ecosystems and humans’ unbridled population growth threatens food security. For this, we can again turn to indigenous cultures for insights. Some of their practices include sustainable irrigation, terracing and systems such as raised-field agriculture. The latter, once used across South and Central America before the Spanish came along, has been attributed to better drainage, soil aeration, moisture retention and fertility. Already, people have tried to rehabilitate prehistoric agricultural methods, for example in the Peruvian Andes where pre-Hispanic terraces have been reintroduced. Many lessons can be learned from these efforts, note Boivin and Crowther, such as the importance of engaging local communities and observing markets. Other insights come from the eastern Amazon up to 4500 years ago, such as complex agroforest practices – rather than modern unsustainable monocrops – that grew multiple crops while creating edible forests. Archaeology can also help explore ancient resilient crops such as millet, a heat-tolerant cereal that colonists replaced with thirsty, labour-intensive maize. “By reviving local crops and other forms of local agriculture we can better address the food crises that we face globally with population growth and climate change,” says Crowther. All of this relies on healthy soil, she and Boivin note. “Soil lies at the base of all human subsistence systems,” they write, “and soil retention and improvement were key foci of human activity in many regions of the world for thousands of years.” Historically, humans created soils that were rich in organic matter, had better capacity to hold nutrients and moisture and were “remarkable” at sequestering carbon. Soil enrichment methods included adding algae to Maya gardens in Mesoamerica, and seaweed to topsoils surrounding the Baltic Sea, in Europe. African savannah soils were unintentionally enriched by prehistoric animal droppings. We can also learn from past patterns of air pollution, a major health hazard that confronts us and reportedly impacted historical populations; how levels are estimated and how it accumulates and breaks down, for instance. Ancient tropical cities in places such as Mesoamerica, Southeast Asia and the Amazon offer insights for sustainable cities. In Maya culture, for instance, households and domestic gardens were interspersed with agriculture in the city itself. “These proximate food staple sources probably contributed to the longevity of many Maya cities,” write Boivin and Crowther. Another example of urban agriculture they note is Byzantine Constantinople, which sustained people even during prolonged sieges. “These early dispersed agrarian cities offer more sustainable, food-secure models of urbanism that are less dependent on fossil fuel and more resilient to food-supply shocks resulting from, for example, pandemics, conflict or climate change.” Such cities also featured cultivation by smallholders, empowering local communities to control their activities and foster food security. Importantly, they included impressive water-conservation technologies. Last but certainly not least, the researchers say we can learn from the past to build greater climate-change resilience, a topic that has long captivated archaeologists who seek to understand past human responses to climate changes. Peruvian archaeology, for instance, offers a window into El Niño patterns. The authors urge that archaeology, in particular, be embraced by and take part in multi-disciplinary efforts to address modern challenges, as well as engaging with policymakers, Indigenous peoples and other stakeholders such as farmers, conservationists, rangers and local communities. “We must work towards solutions that bring together the best of the past, present and future, integrating traditional and modern approaches to find the best way forward.” https://cosmosmagazine.com/people/culture/lessons-from-the-past/
Subscriber CaaC (John)+ Posted January 25, 2021 Subscriber Posted January 25, 2021 Quote PALAEONTOLOGY Past (more) perfect A new technique may sharpen accuracy for measuring past temperatures. Gravitational waves, marine fossils and climate change don’t usually appear in the same sentence, but a unique international research collaboration is building bridges between the disciplines. A team of astrophysicists, palaeontologists and mathematicians used machine learning algorithms – originally developed by gravitational-wave astrophysicists – to improve the accuracy of a “paleothermometer”, which looks at fossil evidence of past climate change to predict Earth’s future. Ice cores and tree rings are perhaps more widely recognised examples of paleothermometers. By studying the trapped air bubbles within ice or the oxygen isotope ratio of tree ring cellulose, researchers can reconstruct the composition of the Earth’s atmosphere over millions of years. This then helps us better understand the planet’s cycles. But this new research– led by palaeontologist Tom Dunkley Jones, from the University of Birmingham, UK – instead studied biomarkers leftover from single-celled organisms called archaea, dating as far back as the Cretaceous (145–66 million years ago). These little critters produce compounds called Glycerol Dialkyl Glycerol Tetraethers (GDGTs). In modern oceans, the abundance of GDGT varies with the local sea temperature, “most likely driven by the need for increased cell membrane stability and rigidity at higher temperatures,” the researchers explain in their paper, which appears in the journal Climate of the Past. Archaea preserved in ancient marine sediments, therefore, have the potential to provide a long-term geologic record of the planet’s surface temperatures. Previous research has combined GDGT concentrations into a single parameter called TEX86, but its accuracy is lacking; when compared to known modern sea-surface temperatures, predictions from TEX86 in recent sediment were several degrees off. “After several decades of study, the best available models are only able to measure temperature from GDGT concentrations with an accuracy of around 6°C,” says co-researcher Ilya Mandel, an Australian gravitational-wave astrophysicist from the ARC Centre of Excellence in Gravitational Wave Discovery (OzGrav). In collaboration with colleagues from the UK, Mandel tried a different approach to make high-precision measurements of ancient climates. They turned to modern machine learning tools that were originally used in gravitational wave astronomy, in order to create predictive models of merging compact objects like black holes and neutron stars. These tools allowed them to take into account all GDGT measurements at once, instead of combining them into a simplified factor of TEX86 – resulting in a far more accurate paleothermometer. The accuracy of the model nearly doubled, from 6°C to 3.6°C. In their paper, the authors point out that using GDGT abundances to estimate temperatures is still an area of emerging research, limited by available calibration constraints and our current understanding of underlying biophysical models. https://cosmosmagazine.com/history/palaeontology/past-more-perfect/
Subscriber CaaC (John)+ Posted March 17, 2021 Subscriber Posted March 17, 2021 Quote The future in steak? The environmental impacts of eating meat are becoming increasingly apparent, from land and water costs to massive greenhouse gas emissions. A 2019 report from the Intergovernmental Panel on Climate Change (IPCC) stated that adopting plant-based diets could be a major opportunity to curb global warming. But humans are omnivores and require protein – so lab-grown meat has become a burgeoning field of research. A new study from the University of Tokyo now reports the biofabrication of bovine muscle tissue in the lab, using techniques developed for regenerative medicine to culture millimetre-sized chunks of meat. Unlike many other forms of cultured meat, this one isn’t mince-like – it’s closer to the grain and texture of real flesh. The researchers achieved this by taking myoblasts (a cell that contributes to muscle growth) from commercial beef and culturing it in an artificial hydrogel scaffolding. They could then stack it into larger chunks, figuring out the optimal structure to simulate steak meat. “Our morphological, functional and food feature analyses showed that the cultured muscle tissue holds promise as a credible steak substitute,” says lead author Yuya Morimoto. “However,” notes co-author Shoji Takeuchi, “there is a long way to go before lab-grown meat is indistinguishable from the real thing and hurdles concerning consumer acceptance and cultural sensibilities are overcome. “Nevertheless, this innovation promises to be a green and ethical alternative to animal slaughter in meeting our need for dietary meat.” The study is published in npj Science of Food. https://cosmosmagazine.com/nature/plants/you-may-have-missed-7/
Azeem Posted June 14, 2021 Author Posted June 14, 2021 I remember a lot more frequent and heavy rains growing up. Weather was always this hot during June-July but patches of windy cool weather in between. Heat waves have become longer.
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