New cold-hardy electrolyte could double EV range

With existing battery electrolytes, many electric vehicles struggle to maintain decent range in cold temperatures

Depositphotos

From New Atlas

A joint team of researchers from Nankai University in Tianjin and the Shanghai Institute of Space Power Sources (SISP) has developed a hydrofluorocarbon-based electrolyte that significantly enhances the performance of lithium batteries. As reported by the South China Morning Post, the new electrolyte more than doubles the energy density of existing batteries at room temperature, meaning batteries of the same size can last twice as long.

The researchers also claim that the new electrolyte remains stable in extreme cold, allowing batteries to function seamlessly in temperatures as low as -94 ºF (-70 ºC), well over 2.5 times the temperature of your refrigerator.

Chemical batteries, such as lithium batteries, utilize electrolytes – a chemical medium that allows ions to flow between the positive and negative electrodes, converting stored chemical energy into electrical current. In lithium batteries, the electrolytes are usually nitrogen- and oxygen-based compounds, mainly because of their effectiveness at dissolving lithium salts.


However, these electrolytes are sensitive to operating temperatures. Cold temperatures increase viscosity and slow down ion mobility, reducing charge transfer efficiency. When this happens, the battery delivers less power, takes longer to charge, and loses usable capacity, providing less runtime than its stored energy would suggest. This is why lithium batteries appear to die quickly in extreme cold. In certain conditions, such as charging the battery when the temperature is below 32 °F (0 ºC), permanent damage may occur.

In the study published in Nature, the researchers outlined how their solution, synthesized hydrofluorocarbon-based (hydrogen, fluorine, and carbon) electrolytes, eliminates this problem in lithium batteries. The cold-resistant electrolyte offers improved stability and lower viscosity at low temperatures, enabling batteries to continue operating efficiently below -94 °F.

Another outstanding feature of the electrolyte is its energy density – the amount of charge it can store per weight. In the study, the team created lithium metal pouch cells that achieved an energy density of 317 watt-hours per pound (Wh/lb) at room temperature. The cells still maintained a density of 181 Wh/lb at -50 °F (-46 ºC).

In comparison, conventional lithium batteries, such as those found in Tesla EVs, have an energy density of 73-136 Wh/lb at room temperature. This figure more than halves when temperatures fall to just -4 °F (-20 ºC).Technically speaking, the researcher’s electrolyte could triple the range of some EVs with the same battery size!

“For the same mass of lithium battery, the room temperature energy storage capacity is increased by two to three times,” said study author Li Yong, a researcher at SISP.

Beyond the automotive industry, this development could have far-reaching implications across many sectors and everyday life. We are talking drones, robots, smartphones, and consumer electronics that last twice as long while still being able to operate efficiently in extreme cold.

Research robots operating in Antarctica could function reliably, while subsea exploration vehicles could significantly extend their operational range. Similarly, satellites and spacecraft, which endure extreme temperature swings in orbit, could benefit from more stable and predictable power systems. The list goes on and on.

Before we get carried away, it's important to note that the electrolytes are not exactly “all weather” ... yet. The team noted that the electrolyte’s high-temperature stability still needs improvement. Should they succeed in raising the boiling point of the electrolyte, we could have a true all-climate solution.

 

Source: Nature 

 

This is obviously still at the laboratory stage, and as such, may never enter commercial production. However, you may depend upon it: engineers at Chinese and other countries' battery manufacturers will have read the article in Nature, and will be keenly examining the results to see if there is any way they can increase the range and reduce the cost of their own batteries.  There is a ferment in battery technology and manufacture, and the likely outcome is more of the same: plunging costs, higher energy density, and greater range.  Sodium-ion batteries, for example, which also allow low-temperature use, are just one of the ways battery makers have slashed costs.  This new electrolyte keeps lithium-ion in the game. 

Direct carbon capture from water, not air

From New Atlas

The oceans soak up enormous quantities of carbon dioxide, and MIT researchers say they've developed a way of releasing and capturing it that uses far less energy than direct air capture – with some other environmental benefits to boot.

Pulling greenhouse gases out of water is an odd-sounding idea, but the oceans are the planet's number one carbon sink, and direct air carbon capture has pretty serious problems: it costs a lot, and uses a lot of energy. According to IEA figures from 2022, even the more efficient air capture technologies require about 6.6 gigajoules of energy, or 1.83 megawatt-hours per ton of carbon dioxide captured.

Most of that energy isn't used to directly separate the CO2 from the air, it's in heat energy to keep the absorbers at operating temperatures, or electrical energy used to compress large amounts of air to the point where the capture operation can be done efficiently. But either way, the costs are out of control, with 2030 price estimates per ton ranging between US$300-$1,000. According to Statista, there's not a nation on Earth currently willing to tax carbon emitters even half of the lower estimate; first-placed Uruguay taxes it at US$137/ton. Direct air capture is not going to work as a business unless its costs come way down.

It turns out there's another option: seawater. As atmospheric carbon concentrations rise, carbon dioxide begins to dissolve into seawater. The ocean currently soaks up some 30-40% of all humanity's annual carbon emissions, and maintains a constant free exchange with the air. Suck the carbon out of the seawater, and it'll suck more out of the air to re-balance the concentrations. Best of all, the concentration of carbon dioxide in seawater is more than 100 times greater than in air.

Previous research teams have managed to release CO2 from seawater and capture it, but their methods have required expensive membranes and a constant supply of chemicals to keep the reactions going. MIT's team, on the other hand, has announced the successful testing of a system that uses neither, and requires vastly less energy than air capture methods.

In the new system, seawater is passed through two chambers. The first uses reactive electrodes to release protons into the seawater, which acidifies the water, turning dissolved inorganic bicarbonates into carbon dioxide gas, which bubbles out and is collected using a vacuum. Then the water's pushed through to a second set of cells with a reversed voltage, calling those protons back in and turning the acidic water back to alkaline before releasing it back into the sea. Periodically, when the active electrode is depleted of protons, the polarity of the voltage is reversed, and the same reaction continues with water flowing in the opposite direction.

In a new study published in the peer-reviewed journal Energy & Environmental Science, the team says its technique requires an energy input of 122 kJ/mol, equating by our math to 0.77 mWh per ton. And the team is confident it can do even better: "Though our base energy consumption of 122 kJ/mol-CO2 is a record-low," reads the study, "it may still be substantially decreased towards the thermodynamic limit of 32 kJ/mol-CO2."

The team projects an optimized cost around US$56 per ton of CO2 captured – although it's not fair to compare that directly against full-system direct air capture costs. The study cautions that this does not include vacuum degassing, filtration and "auxiliary costs outside of the electrochemical system" – analyses of which will have to be done separately. Some of these, however, could potentially be mitigated by integrating the carbon capture units in with other facilities, for example desalination plants, which are already processing large volumes of seawater.

There are some other benefits too; increased carbon buildup in the ocean over recent years has already caused problems with acidification, threatening coral reefs and shellfish. The alkaline output of this process, if directed where it's needed, could help redress the balance.

The team has a practical demonstration project planned for sometime in the next two years, and says there are plenty of things that still need work. For one, the researchers would love to be able to separate the gas out without a vacuum system. And mineral precipitates are fouling the electrodes on the alkalinization side, so there's plenty of progress yet to be made.

The study is open access in the journal Energy & Environmental Science.

Omega-3 supplements reduce aggression

Source: Depositphotos

From New Atlas

Fish oil supplements containing omega-3 have long been touted as good for heart health. A new study has found they also reduce aggression. Researchers say the safe, common supplements should be used everywhere from the playground to the prison system.

Overt acts of aggression include verbal and physical violence and bullying. Then, there are covert signs like vandalism and property damage, fire-setting, and theft. Both can negatively affect relationships and have legal consequences. It goes without saying that, on many levels, society would be better off if aggressive behaviors were reduced. A new study may have discovered a way of doing that.

The study by researchers from the University of Pennsylvania (Penn) found that commonplace omega-3 supplements reduced aggression, regardless of age or gender.

“I think the time has come to implement omega-3 supplementation to reduce aggression, irrespective of whether the setting is the community, the clinic, or the criminal justice system,” said Adrian Raine, a Penn neurocriminologist and the lead and corresponding author of the study. “Omega-3 is not a magic bullet that is going to solve the problem of violence in society. But can it help? Based on these findings, we firmly believe it can, and we should start to act on the new knowledge we have.”

Omega-3 has enjoyed a strange association with violent behavior for a while. Back in 2001, Dr Joseph Hibbeln, a senior clinical investigator at the US National Institutes of Health (NIH), published a study finding a correlation between the consumption of high amounts of fish (a rich source of omega-3) and lower homicide rates. The following year, the University of Oxford in the UK led a study where British prisoners were given nutritional supplements that included vitamins, minerals and essential fatty acids. The researchers found that prisoners given supplements were less violent and antisocial.

In addition to examining the effect of omega-3 supplements on aggression, the researchers in the current study particularly wanted to ascertain whether omega-3 was effective for all forms of aggression. In psychology, a distinction is made between ‘reactive’ aggression, an in-the-moment response to a perceived threat or provocation, and ‘proactive’ aggression, which requires planning.

The researchers conducted a meta-analysis of 29 randomized controlled trials that explicitly measured aggression in people who’d been given omega-3 supplements. They specifically focused on aggressive behavior and not broader traits like anger, which is viewed more as a feeling or emotion, and hostility, which is more of an attitude. Studies where additional nutritional supplements, such as calcium and vitamin D, were included, but the researchers examined them as a potential moderator.

A modest short-term effect linked to omega-3 supplementation, which the researchers say equates to a 30% reduction in aggression, was seen across age, gender, baseline diagnosis, treatment duration and dosage. Notably, omega-3 was found to reduce both reactive and proactive aggression. The researchers were limited to short-term data because only one out of the 19 laboratories conducting the studies followed up with participants after supplementation ended.

The researchers explain how they think omega-3 exerts its effects. Previous studies have pointed to aggressive and violent behavior having a cognitive and neurochemical basis. And, omega-3 is known to play a critical role in brain structure and function, including regulating neurotransmitters and gene expression, and reduces brain inflammation.

“As such, given the undeniable fact that omega-3 is pervasively involved in multiple facets of neuronal biology, it is reasonable to believe that omega-3 supplementation could play a causal role in reducing aggression by upregulating brain mechanisms that may be dysfunctional in … individuals, given the assumption that there is, in part, a neurobiological basis to aggression,” said the researchers.

Further studies are needed to assess the long-term effectiveness of omega-3 supplementation on reducing aggression. Other research avenues would be using MRI scans to determine whether omega-3 enhances brain functioning and examining whether genetics affects omega-3 treatment. In the meantime, the researchers say there is little harm in people, including children, taking this widely available, safe and inexpensive dietary supplement.

“At the very least, parents seeking treatment for an aggressive child should know that in addition to any other treatment that their child receives, an extra portion or two of fish each week could also help,” Raine said.

And the researchers say omega-3 should be used in conjunction with existing psychological and psychiatric treatments.

“[W]e would argue that omega-3 supplementation should be considered as an adjunct to other interventions, whether they be psychological (e.g. CBT [cognitive behavioral therapy]) or pharmacological (e.g. [the antipsychotic drug] risperidone) in nature, and that caregivers are informed of the potential benefits of omega-3 supplementation,” the researchers said.

The study was published in the journal Aggression and Violent Behavior.

Source: University of Pennsylvania

 

Gold nano-crystals for Parkinson's and MS

From New Atlas

Phase 2 clinical trials using orally administered gold nanocrystals to treat multiple sclerosis and Parkinson’s disease have produced promising results, restoring metabolites linked to crucial energy activity in the brain that are depleted in these neurodegenerative conditions.

The brain depends on a continuous supply of energy in the form of adenosine triphosphate (ATP) to fuel its resting and active-state functions. Essential to ATP production is the molecule nicotinamide adenine dinucleotide (NAD+).

As glucose is broken down into smaller molecules by the cells, the chemical bonds holding it together break. The energy held in the broken bonds is harnessed when an electron freed during the process is captured by NAD+, converting it to its reduced form, nicotinamide adenine dinucleotide + hydrogen (NADH). NADH donates the electron to the mitochondria, which use the electron’s energy to produce ATP, a process that oxidizes NADH back to NAD+.

Energy metabolism is compromised as we age, evidenced by a reduced NAD+/NADH ratio, which is considered a measure of global brain energy capacity. In neurodegenerative diseases like multiple sclerosis (MS), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS), this reduction is much faster and more severe.

Now, researchers from the University of Texas Southwestern (UT Southwestern) Medical Center have conducted two phase 2 clinical trials on patients with MS and PD to see whether treating these neurodegenerative diseases with orally administered gold nanocrystals could restore the NAD+/NADH ratio.

“We are cautiously optimistic that we will be able to prevent or even reverse some neurological disabilities with this strategy,” said Peter Sguigna, one of the study’s co-authors and lead on the MS trial.

CNM-Au8 is a concentrated suspension of gold nanocrystals whose surfaces catalyze the rapid oxidation of NADH to NAD+, shown to increase the availability of both NAD+ and ATP in in vitro studies. It’s also known to cross the blood-brain barrier and penetrate cell membranes.

The objective of the clinical trials was to demonstrate the effects of CNM-Au8 on key brain energy metabolites, including ATP, total NAD+ and the NAD+/NADH ratio, in the setting of neurodegenerative disease. The REPAIR-PD trial recruited 13 participants aged 30 to 80 with a diagnosis of PD. Participants had a disease duration equal to or less than three years and were receiving dopaminergic medications for the disease for at least 12 weeks, with no change in dose for at least six weeks before starting the trial. The REPAIR-MS trial recruited 11 participants aged 18 to 55 with a diagnosis of stable relapsing MS within 15 years of screening, a form of the condition that’s marked by worsening symptoms (relapse) followed by a period of remission. Participants were receiving treatment with the immunotherapy drug natalizumab.

All participants received 120 ml of CNM-Au8, which they drank each morning for 12 weeks. Beginning with the baseline visit, participants had ECG, blood tests, physical exams, and scoring of either motor and non-motor Parkinson’s symptoms or the degree of disability caused by MS. Phosphorous magnetic resonance spectroscopy (P-MRS) was used to noninvasively assess energy metabolites of the whole brain.

After 12 weeks of treatment with CNM-Au8, the mean change in NAD+/NADH ratio from baseline across both cohorts demonstrated a statistically significant increase by an average of 10.4%, demonstrating that the gold nanocrystals were targeting the brain as intended. The effect on the NAD+/NADH ratio ceased after the 12-week CNM-Au9 treatment was concluded. The researchers also observed an inverse correlation between the baseline and post-treatment levels of ATP and other brain energy metabolites; participants with relatively lower baseline levels demonstrated increases, and participants with relatively higher baseline levels demonstrated a re-balancing that brought levels down.

In participants with PD, the treatment produced a statistically significant improvement in scores measuring “motor experiences of daily living,” driven mainly by a significant improvement at week four. This score reflects the impact rather than the presence of symptoms and includes an assessment of chewing and swallowing, cutting food and handling utensils, dressing, hygiene, speech, writing, walking, and the interference caused by tremor.

Adverse events were reported as mild or moderate, none of which were considered by the researchers to be related to the study drug. Common side effects included sinusitis, the common cold, and ‘pins and needles’.

“To our knowledge, CNM-Au8 is the only drug in development with catalytic activity targeted at intracellular NADH conversion to NAD+ with a demonstrated, potentially beneficial, effect on these metabolites in participants with neurodegenerative disease,” said the researchers.

The REPAIR-MS trial is ongoing, enrolling participants to see whether similar findings can be reproduced in those with progressive MS, characterized by worsening symptoms without relapses or remissions.

The researchers say that the results of these clinical trials support advancing to larger phase 3 trials to test whether CNM-Au8 offers a treatment benefit to those with neurodegenerative diseases.

Clene Nanomedicine Inc., which produced the CNM-Au8 oral suspension, funded the study published in the Journal of Nanobiotechnology.

Clinical trials using orally administered gold nanoparticles produced promising results in treating neurodegenerative diseases

Original images: Clene Nanomedicine

Hybrid-electric plane rakes in $8 billion in orders

From NewAtlas

In all the buzz around eVTOLs, there's still plenty of appetite for more conventional electric planes – especially, it seems, if they make ludicrous amounts of lift, and can take off and land at incredibly slow speeds, using absolutely tiny runways.

Electra's hybrid-electric STOL (short takeoff and landing) aircraft is one such plane. When it hits the market, it'll carry nine passengers, and a pilot, plus luggage, up to 500 miles (805 km) at a cruise speed around 200 mph (322 km/h). It'll run eight electric props along the leading edge of the wings, as well as large flaps hanging from the trailing edges. This allows a "blown lift" aerodynamic effect powerful enough that it'll lift off at a speed of just 35 mph (56 km/h).

And it'll accelerate to that speed quickly – meaning that you can use a runway smaller than a soccer pitch. Electra says it'll operate from airfields as small as 300 x 100 ft (92 x 31 m), and seems to imply that'll fit on the top of some buildings. Either way, it's one-tenth the size of a standard runway, so even if these things won't open up as many spaces as eVTOLs, they'll still be extremely flexible.

Plus, as investors are no doubt pleased to note, it functions more or less as a regular plane, so the path to certification and commercial deployment should be much smoother and easier to navigate, with plenty of precedents and fewer unknowns than the eVTOL teams face.

Electra flew a two-seat prototype in November, as shown in the video above, and it'll continue flight tests as it works on a full-scale nine-seat prototype that's scheduled to fly in 2026. The target date for certification and entry into service is sometime in 2028.

And the market is listening, it seems. Electra says it's taken pre-orders for more than 2,000 aircraft, worth more than US$8 billion. That's considerably higher than the biggest pre-seller in the eVTOL field – Vertical Aerospace, which has 1,500 aircraft pre-sold for a total over $5 billion.

That's pretty fascinating – eSTOL represents a much more conventional approach with far less disruptive, world-changing potential than eVTOLs, which in theory could have us zooming from rooftop to rooftop in and around urban areas within a few years.

But the market likes this small-runway, half-electric, nine-passenger, regional-capable proposition enough to sign $8 billion dollars' worth of pre-orders – eight times as much revenue as Cessna brings in a year, according to Growjo. Seems odd to us, but such are the times! 

Just as with cars, the first commercial electric planes are likely to be hybrids, i.e., they'll have a jet turbine to generate electricity to extend the range.  The engines themselves won't be hybrid.  As battery energy density increases, range will be extended, and eventually the jet turbine will be dispensed with.  Even a hybrid-electric plane will reduce emissions, in some cases by up to 50%.  And of course, on shorter trips, they will be fully electric.  As with Heart Aerospace's ES-30 (which can carry 30 passengers), operating costs will be far below those of a fossil-fuelled plane, so routes to smaller towns will be enabled.  In the case of Electra's plane,  they will also not need to build expensive runways.  Football fields will do!

New category 6 for recent mega-hurricanes

From New Atlas

Climate change looks set to trigger stronger storms more often, and the threat may not be properly communicated to people in the line of fire. Now, scientists at Lawrence Berkeley National Laboratory suggest there’s room for a Category 6 on the scale – with five storms in the past decade already reaching that strength.

Currently, the National Hurricane Center uses a measure called the Saffir-Simpson Windscale to classify the intensity of hurricanes in the Western Hemisphere and alert people in the area to take appropriate precautions. It’s based on the maximum wind speeds in the storm averaged over a minute – it starts at 74 mph (119 km/h) for a Category 1 hurricane, and goes through different thresholds all the way up to Category 5, which is everything over 157 mph (252 km/h). But because the destructive power of wind increases exponentially, and with hurricane strength growing in recent years, scientists at Berkeley Lab and the First Street Foundation weren’t sure if that scale told the full story.

“Our motivation is to reconsider how the open-endedness of the Saffir-Simpson Scale can lead to underestimation of risk, and, in particular, how this underestimation becomes increasingly problematic in a warming world,” said Michael Wehner, first author of the study.

Tropical storms form out of interactions between warm ocean water and warm, humid air, and those temperatures are increasing rapidly, thanks to human-induced climate change. This seems set to boost not just the intensity of hurricanes but the speed that they gain power.

In the new study, the team added an extra hypothetical category to the scale. Based on the ranges of lower categories, they suggested that Category 5 would cover storms with wind speeds between 157 and 192 mph (252 and 309 km/h), while the new Category 6 would include any storm that became more powerful than that upper bound.

When the researchers analyzed historical data of hurricanes from 1980 to 2021, they identified five storms that reached strengths high enough to fall into that hypothetical Category 6. That includes Hurricane Patricia, the most powerful tropical cyclone on record, which battered Central America with winds of up to 215 mph (345 km/h) in 2015.

Worryingly, but perhaps not surprisingly, all five hypothetical Category 6 hurricanes occurred within the last nine years. That lends weight to the contributions of climate change to their intensity. The team admits the research isn’t a formal proposal for a restructure of the Saffir-Simpson Scale, but is intended to bring attention to its potential shortcomings.

“Tropical cyclone risk messaging is a very active topic, and changes in messaging are necessary to better inform the public about inland flooding and storm surge, phenomena that a wind-based scale is only tangentially relevant to,” said James Kossin, co-author of the study. “While adding a 6th category to the Saffir–Simpson Hurricane Wind Scale would not solve that issue, it could raise awareness about the perils of the increased risk of major hurricanes due to global warming.”

The research was published in the journal PNAS.

Source: Lawrence Berkeley National Laboratory

 

Hurricane Patricia, the strongest hurricane on record, as captured by astronaut Scott Kelly from the International Space Station in 2015

Scott Kelly/NASA

2023 confirmed as hottest year ever

From New Atlas

It’s official: 2023 was the hottest year on record. Independent analyses by NASA, NOAA, WMO, Copernicus and the UK Met Office all reached the same conclusion, with the year also breaking a slew of other records and experiencing a string of severe weather events across the globe.

Each organization works with a slightly different data set and techniques, resulting in minor variations between the exact numbers they reach. However, all five were in agreement that 2023 was warmer than previous record-holder, 2016, by a wide margin.

NASA found that global average surface temperatures were 1.2 °C (2.1 °F) above the baseline period it uses – 1951 to 1980. NOAA gets its average across the whole 20th century, finding that 2023 was 1.18 °C (2.12 °F) higher than that. Copernicus, WMO and the Met Office use a pre-industrial baseline of 1850 to 1900, finding 2023 to be 1.45 to 1.48° C (2.61 to 2.66 °F) higher than that. Regionally, Africa, North and South America experienced their hottest year on record, while it was the second-hottest in Europe and Asia.

Other temperature records were also reached throughout the year. Each month from June to December set a global record for that respective month, with July 2023 being the hottest month of any ever recorded, while also including both the hottest day and week on record, and culminating in the Northern Hemisphere experiencing the hottest summer on record. For the first time ever, every single day of 2023 was more than 1 °C (1.8 °F) warmer than the pre-industrial average, and almost half were over 1.5 °C (2.7 °F) warmer. Two days in November were more than 2 °C (3.6 °F) warmer than that average, a threshold which hadn’t been crossed before.

Oceans suffered too. Global ocean surface temperatures saw record highs every month between April and December, while Antarctica saw its sea ice reach the smallest ever maximum and minimum extents. Upper ocean heat content was also the highest on record – a value that measures how much heat is stored in the upper 2,000 m (6,560 ft) of the ocean. That leads to the atmosphere retaining more of its heat and water vapor, in turn leading to more extreme weather.

And there was no shortage of that in 2023. Globally, tropical storms had above average activity, with 45 hurricanes/cyclones/typhoons, capped off with Cyclone Daniel, the deadliest storm to hit Africa in recorded history, killing over 10,000 people. Wildfires in Canada burned the largest area on record for North America, exacerbated by record-breaking heat waves on the continent.

Worryingly, 2024 is in a strong position to steal the crown for hottest year. One of the main contributors to global climate is the El Niño-Southern Oscillation cycle, which kicked off an El Niño event in mid-2023. These raise global temperatures, as seen in the back half of the year – but it’s not predicted to reach its peak until February, March and April 2024.

As always, the scientists involved in the studies are pointing to human-induced climate change, which is increasingly manifesting in alarmingly visible ways. Let’s just hope the warnings don’t fall on deaf ears.

“After seeing the 2023 climate analysis, I have to pause and say that the findings are astounding,” said Dr. Sarah Kapnick, NOAA Chief Scientist. “Not only was 2023 the warmest year in NOAA’s 174-year climate record — it was the warmest by far. A warming planet means we need to be prepared for the impacts of climate change that are happening here and now, like extreme weather events that become both more frequent and severe.”

 

Click to enlarge

Cardboard foam packaging

From New Atlas

Thanks to the popularity of online shopping, an increasing number of goods are being shipped to buyers in cardboard boxes filled with eco-unfriendly EPS (expanded polystyrene) foam. Soon, however, such boxes could be upcycled into a greener alternative to EPS.

Not only is polystyrene derived from petroleum (the extraction and refinement of which is harmful to the environment), the foam made from it is very difficult to recycle, it's non-biodegradable, and it takes up a disproportionately large amount of space in landfills.

Seeking a more Earth-friendly alternative, Assoc. Prof. Jinsheng Gou and colleagues at Beijing Forestry University looked to cardboard waste. That waste could even include the very boxes in which EPS-packed products are shipped.

The scientists used a blender to break cardboard scraps down into a cellulose-fiber pulp, which was then mixed with either glycerol gelatin or polyvinyl acetate (PVA) glue. These mixtures were subsequently poured into moulds, refrigerated, and finally freeze-dried to form biodegradable cushioning foams.

Those foams proved to have good thermal insulating qualities, plus they absorbed impact energy even better than some petroleum-based foams.

Next, the researchers combined the pulp, gelatin and PVA glue with a silica-based shear-thickening fluid that hardens when subjected to force. The resulting heavy-duty foam was able to withstand being struck by a hammer without falling apart, raising hopes that it might someday find use in applications such as parachute-free cargo drops from aircraft.

A paper on the study was recently published in the journal ACS Sustainable Chemistry & Engineering.

Source: American Chemical Society

Gene Therapy for spinal damage

From New Atlas

A complete spinal cord injury results, tragically, in total paralysis of all limbs and muscles below the injury site. But now, scientists at EPFL have demonstrated in mice a new gene therapy that can regenerate nerves and restore the ability to walk.

The spinal cord is, to use an outdated tech term, the information super-highway of the body. Messages between the brain and every other part of the body travel up the thick bundle of nerves there at incredibly fast speeds. As such, damage to this conduit can be debilitating, leaving patients with no sensation or mobility in affected areas.

Unsurprisingly, finding new ways to repair these injuries is a key area of research, with recent studies finding some success using implants that bypass the injured area, nerve cell transplants, and proteins, molecules or compounds that help stimulate nerve regrowth. The EPFL team had previously managed to regenerate nerve fibers using gene therapy, but had limited success.

“Five years ago, we demonstrated that nerve fibers can be regenerated across anatomically complete spinal cord injuries,” said Mark Anderson, senior author of the study. “But we also realized this wasn’t enough to restore motor function, as the new fibers failed to connect to the right places on the other side of the lesion.”

To fix the issue, the researchers studied the natural repair processes that take place after a partial spinal cord injury. Using a technique called single-cell nuclear RNA sequencing, the team identified the specific axons that need to be repaired to restore motor function, and how they can find the right target on the other side of the injury.

From this analysis, the researchers developed a new gene therapy that works in a few ways at once to boost the reconnection of nerves. The therapy activates growth programs in certain neurons to regenerate the key nerve fibers, upregulates certain proteins that help the neurons grow through the damaged tissue, and added molecules that guide those regenerating nerves to their targets on the other side.

In tests in mice with complete spinal cord injuries, the team found that the treated animals regained the ability to walk in a matter of months, ending up with a gait similar to those of mice that had recovered from a partial injury.

While there’s still plenty more work to be done before this kind of therapy could be applied to humans, the team says that it marks a key step towards that eventual goal.

“We expect that our gene therapy will act synergistically with our other procedures involving electrical stimulation of the spinal cord,” said Grégoire Courtine, senior author of the study. “We believe a complete solution for treating spinal cord injury will require both approaches – gene therapy to regrow relevant nerve fibers, and spinal stimulation to maximize the ability of both these fibers and the spinal cord below the injury to produce movement.”

The research was published in the journal Science.

Spare a thought for the mice who suffered and died in this experiment.

China: petrol demand has peaked

From New Atlas

China's extremely rapid adoption of EVs has forced oil giant Sinopec to adjust its forecasts, saying peak domestic gasoline demand has already passed and it's all downhill from here. The repercussions will be global; China has been the biggest growth market for refined oil products for more than 20 years.

According to CNEV Post, Chinese new car buyers are now choosing "new energy vehicles" (NEVs, meaning battery-electric and plug-in hybrid cars) at a rate of 37.8%, a percentage which has rocketed up from 30.0% in 2022, 15.5% in 2021 and just 5.4% in 2020.

While Scandinavian countries like Norway (87.8%), Iceland (56.1%) and Sweden (56.1%) led the world for EV adoption in 2022, China sells somewhere around 10 times more EVs than all those three combined, and there's a lot more room for growth in the world's second-most populous country, since as of 2022, less than 5% of cars on Chinese roads were NEVs.

So China's largest oil company Sinopec is already seeing a drop in demand, from which it doesn't expect to recover. Previous predictions placed peak demand somewhere in 2025, but at a conference in Zhengzhou in August, Bloomberg reported that one Zhou Yan, from Sinpoec's retail sales division, said EVs were already displacing some 15 million tons of Chinese oil product sales in 2023, and that the company is forecasting that 2024 and subsequent years will see declining demand.

According to the International Energy Agency, Chinese demand accounted for more than 70% of global oil market growth in 2023, so while global oil product sales are at record highs of around 102.2 million barrels per day in 2023 (up around 2.2 million barrels per day over figures from 2022), and gasoline for passenger cars is only a percentage of total oil product demand, it'll be interesting to see how China's rapid EV uptake affects predictions for global peak oil demand.

The IEA released its forecast in June, estimating that peak global oil use for transport will arrive around 2026, but strong demand from the petrochemical and aviation sectors would continue to support overall market growth, albeit at slower rates, at least as far out as 2028.

A global oil demand peak, then, could arrive before the end of the decade. And unexpectedly rapid transitions to cleaner vehicles like what we're seeing in China, as well as continued increases in fuel economy for new fossil burners, could bring that date closer.

From  Bloomberg

Fuel demand in two and three-wheeled vehicles is already in structural decline, with BNEF estimating that 70% of total kilometers traveled by these vehicles already switched over to electric. Fuel demand for cars will be the next to turn, since well over 5% of the passenger-vehicle fleet is now either battery-electric or plug-in hybrid. The internal combustion vehicle fleet is also becoming more efficient due to rising fuel-economy targets.

Diesel demand for heavier vehicles will keep growing for a bit longer, but even there a seismic shift is underway. Electric, fuel cell and battery-swapping options have quickly climbed to 12% of light commercial vehicle sales and 4% to 5% of medium and heavy commercial vehicle sales. That heavy-duty figure is likely to climb to over 10% by 2025.

Combine all those segments, and BNEF expects total oil demand for road transport in China to peak late next year. Demand won’t drop off a cliff anytime soon — fleet turnover in the trucking segment in particular will take time — but it still marks a major shift for global oil demand patterns. It also has big implications for refiners that need to quickly adjust the mix of products they produce.

100% recyclable rubber-free tyres

 From New Atlas

Because they're made of vulcanized rubber, old tires can't simply be melted down and used to make new tires. Such is reportedly not the case, however, with new rubber-free tires made from eco-friendly elastomers.

Although conventional tires can be recycled, they're typically ground into rubber crumbs that are utilized in materials such as asphalt. Since the vulcanization process is not reversible, using them in the production of new tires generally isn't an option.

That's where Norwegian company reTyre comes in.

It has started making tires out of proprietary bio-based TPEs (thermoplastic elastomers), which are claimed to be 100% recyclable. In other words, entire tires made from the material – including both the casing and the beads – can be recycled into more tires.

Total manufacturing costs are said to be comparable to those of rubber tires, as the company's "advanced production technology" allows the tires to be produced at relatively small regional factories as opposed to larger far-away plants. This should result in much lower shipping-related CO2 emissions, and lower shipping costs. What's more, the production process is claimed to use up to 90% less energy.

"Generally speaking, TPEs are a little pricier than rubber," reTyre brand designer Friedemann Ohse told us. "But since our machines are small and our tires will be locally produced, it will save companies a lot of time and money due to short supply chains (freight costs) and reduced waiting time."

Importantly, Ohse also stated that the material lasts longer than rubber, and has better abrasion resistance.

reTyre is now seeking industry partners who may be interested in utilizing the technology in the production of their own tires. The company can be contacted via its website.

 

Computer chip with built-in brain tissue

From New Atlas

Last year, Monash University scientists created the "DishBrain" – a semi-biological computer chip with some 800,000 human and mouse brain cells lab-grown into its electrodes. Demonstrating something like sentience, it learned to play Pong within five minutes.

The micro-electrode array at the heart of the DishBrain was capable both of reading activity in the brain cells, and stimulating them with electrical signals, so the research team set up a version of Pong where the brain cells were fed a moving electrical stimulus to represent which side of the "screen" the ball was on, and how far away from the paddle it was. They allowed the brain cells to act on the paddle, moving it left and right.

Then they set up a very basic-reward system, using the fact that small clusters of brain cells tend to try to minimize unpredictability in their environment. So if the paddle hit the ball, the cells would receive a nice, predictable stimulus. But if it missed, the cells would get four seconds of totally unpredictable stimulation.

It was the first time lab-grown brain cells had been used this way, being given not only a way to sense the world, but to act on it, and the results were impressive.

Impressive enough that the research – undertaken in partnership with Melbourne startup Cortical Labs – has now attracted a US$407,000 grant from Australia's National Intelligence and Security Discovery Research Grants program.

These programmable chips, fusing biological computing with artificial intelligence, "in future may eventually surpass the performance of existing, purely silicon-based hardware," says project lead, Associate Professor Adeel Razi.

"The outcomes of such research would have significant implications across multiple fields such as, but not limited to, planning, robotics, advanced automation, brain-machine interfaces, and drug discovery, giving Australia a significant strategic advantage," he said.

The DishBrain's advanced learning capabilities, in other words, could underpin a new generation of machine learning, particularly when embodied in autonomous vehicles, drones, and robots. It could give them, says Razi, "a new type of machine intelligence that is able to learn throughout its lifetime."

The technology promises machines that can continue to learn new abilities without compromising old ones, that can adapt well to change, and that can map old knowledge onto new situations – while continually self-optimizing their use of computing power, memory and energy.

"We will be using this grant," says Razi, "to develop better AI machines that replicate the learning capacity of these biological neural networks. This will help us scale up the hardware and methods capacity to the point where they become a viable replacement for in silicon computing."

Phenomenal stuff.

Source: Monash University

Whatever next?   

But how do they keep the brain cells alive?   How do they stop the array of electrodes from being gunked up by nutrients for the brain cells?

A microscope image of neurons within DishBrain, with cells highlighted using fluorescent markers

Cortical Labs
[Looks like galaxies!]

A scanning electron microscope image of DishBrain neurons growing on an array of electrodes

Cortical Labs

Reusable sponge removes heavy metals from water

From New Atlas

Removing heavy metal pollutants from water could soon be easier than ever, thanks to an experimental new sponge. With just one treatment, the device brought contaminated water down to safely drinkable levels.

Building upon two previous studies, the technology is being developed by scientists at Illinois' Northwestern University.

The researchers started out with a cheap commercially available cellulose sponge, and placed it in a slurry of manganese-doped goethite nanoparticles. They then removed it, let it dry, and rinsed it with water to flush out any loose particles.

The result was a sponge with a high-surface-area nanoparticle coating that was just tens of nanometers thick. Manganese-doped goethite particles were chosen not only because they adsorb lead ions, but also because they're inexpensive and non-toxic to humans.

When the sponge was immersed in tap water containing more than one part per million of lead, it sequestered lead ions to the point that they were no longer detectable in the water … this made the water safe to drink.

What's more, the lead could subsequently be removed from the sponge by rinsing the latter in mildly acidic water. That reclaimed lead could then conceivably be utilized in products such as batteries, while the rinsed-out sponge was reused to treat more tainted water – it wasn't quite as effective in later cycles, although it was still able to remove over 90% of lead ions from samples.

The scientists have now developed a platform known as Nanomaterial Sponge Coatings for Heavy Metals (Nano-SCHeMe), to guide other teams in selecting different types of nanoparticles for sequestering different types of heavy metals.

"The presence of heavy metals in the water supply is an enormous public health challenge for the entire globe," said Prof. Vinayak Dravid, senior author of a paper on the study. "It is a gigaton problem that requires solutions that can be deployed easily, effectively and inexpensively. That’s where our sponge comes in. It can remove the pollution and then be used again and again."

The paper was recently published in the journal ACS ES&T Water.

Source: Northwestern University

The sponge sequesters lead ions from water, plus it can be rinsed out and reused

Northwestern University

Rheumatoid arthritis linked with gut bacteria imbalance

From New Atlas

Impressive new research led by a team from University College London is suggesting bacterial imbalances in the gut microbiome may play a major role in the development of rheumatoid arthritis. The preclinical study found damage to the gut lining directly correlates with joint inflammation and arthritis severity.

For some time now researchers have reported consistent links between gut microbiome abnormalities and rheumatoid arthritis, and increasing populations of certain types of bad bacteria have frequently been associated with arthritis severity.

But exactly how bacteria in the gut could influence joint inflammation has so far been unclear. A number of mechanisms have been hypothesized, from gut bacteria modulating the development of the specific inflammatory cells responsible for arthritis, to particular bacterial metabolites contributing to disease severity. This new study investigated a different causal hypothesis, focusing on the links between arthritis severity and a bacteria-induced weakening of the gut wall.

“We wanted to know what was happening in the gut and whether changes to the intestinal lining – which usually acts as a barrier to protect the body from bacteria – are a feature of the disease and contribute to its development,” explains co-lead author Claudia Mauri.

The new study showed mice bred to have a genetic predisposition to gut permeability also developed signs of severe arthritis. A different mouse model, engineered to develop collagen-induced arthritis, was then found to display reduced joint swelling when gut permeability was improved.

Looking at human patients the researchers found those suffering from rheumatoid arthritis had higher blood levels of lipopolysaccharide (LPS), LPS binding protein (LBP), and intestinal fatty acid binding protein. All these molecules are known biomarkers of intestinal damage, and LBP levels in particular were found to correlate with acute disease severity.

“Researchers at University College London have shown that, in arthritis, there is profound damage to the gut lining, which fails to work properly as a barrier, as well as an accumulation in the gut of white blood cells that cause inflammation,” the authors write in the newly published study. “The authors show that, in arthritis, bacteria cross the prohibited border of the intestinal lining and that repairing gut permeability defects with specific drugs inhibits joint inflammation.”

The research cannot completely explain the chain of mechanisms that link this weakening of the gut lining with arthritis. So although modulating the degree of gut permeability was found to directly relate to joint inflammation there are still missing links in that relationship yet to be described.

Mauri does say, however, these finding do indicate the gut could be a useful therapeutic target. She particularly speculates that improving gut permeability may be an effective new treatment model.

“Our findings suggest that the intestinal lining is a therapeutic target,” says Mauri. “Importantly, we found that using existing drugs that restore the gut-barrier integrity i.e., prevent the gut from becoming leaky or inhibit inflammatory cells from moving to and from to the gut, could reduce the severity of arthritis in pre-clinical models.”

The new study was published in the journal Med.

Source: University College London

 

Earth-packed tyre wall as good as concrete

From New Atlas

Australian researchers have analyzed the structural properties of walls made from end-of-life car tires packed with dirt, giving engineers some figures to work with and making a well-known upcycling technique available to the construction industry.

Car tires are an environmental nightmare. Ubiquitous, consumable, filthy to burn and they take hundreds of years to decompose in landfill, where an awful lot of them end up. Any project that can recycle them, like grinding them up for use as asphalt filler or insulation, or using them as swings and bumpers in kids' playgrounds, is an environmental boon.

For decades, people have been recycling yesterday's rubber donuts into tomorrow's tire walls, stacking them in staggered formations and packing them with dirt. You'd have seen this kind of thing plenty at motor racing facilities – indeed, some tires have been unusually keen to get involved. The Earthship movement takes the idea further, creating retaining walls and entire buildings out of tire walls, sometimes filling them with concrete rubble and broken bricks to allow for drainage, or even rendering over the top for a smoother appearance.

These kinds of projects, though, are pretty niche. And researchers at the University of South Australia saw an opportunity in the 55 million tires the country disposes of every year. This 450,000-odd tonnes of toxic garbage could become free building materials for use in all sorts of mainstream construction projects if it was studied and documented to the point where engineers can use it.

"The lack of supporting data has prevented wider uptake of tire walls by engineers and architects, and we’re hoping this study will change that and expand the range of projects in which these walls are used," said Dr. Martin Freney, co-author of a new study that submits these tire walls to a full structural analysis. "The wall we tested was the first of its kind to be scientifically tested in this fashion, and all the data indicates tire walls can be extremely strong and safe structures.”

"Not only are the tire walls as structurally sound as concrete or wood sleeper retaining walls, they are also extremely resilient," he continued. "Unlike a concrete wall, we found these walls have the ability to ‘bounce back into shape’ following impact, such as from an earthquake. And if a drainage material such as recycled concrete rubble or crushed bricks is used to fill the tires, they also offer excellent drainage, which can be a major consideration in many retaining wall scenarios. Furthermore, the use of recycled fill materials reduces the environmental impact of the wall."

Weight training cuts death risk by 20%

From New Atlas

Research continues to demonstrate how the health benefits of weight training go far beyond cultivating the ideal beach body. The latest study to shed light on this topic explores the links between muscle-strengthening activities and risk of death, and found that as little as 30-60 minutes of this activity per week could have a significant impact on our longevity.

The research was undertaken by scientists in Japan and involved a systematic review of 16 studies on the exercise habits of adults without serious health problems. This covered the muscle-strengthening activities of hundreds of thousands of men and women aged between 18 and 97, and enabled the researchers to tease out new insights around the mortality risk associated with different lifestyles.

While research has found regular muscle-strengthening carries a lower risk of death generally, the authors of the new study sought to really drill into what the ideal amount might be. Their systematic review revealed that a maximum effect was tied to 30-60 minutes of muscle-strengthening exercise per week, which lowered the risk of death from any cause by 10 to 20%.

Examples of muscle-strengthening include lifting weights, resistance band exercises, push-ups, sit-ups, squats and even heavy gardening with a shovel. The team also found that undertaking this type of activity for up to 60 minutes a week was associated with a sharp risk reduction for diabetes. Interestingly, the research also found no conclusive evidence that doing more than an hour of muscle-strengthening had any extra benefit.

Combining muscle-strengthening activities with aerobic exercise was found to have even more profound effects. This combination was associated with a 40% decrease in risk from any cause, 46% decrease in risk of death from cardiovascular disease and 28% decrease in risk of death from cancer.

There are a few limitations of the study worth noting, with the reviewed literature based on subjective assessments of muscle-strengthening activities, rather than close observation in a clinical setting, and that most were carried out in the US. The authors hope to carry out further research on more diverse populations to really cement the findings.

The research was published in the British Journal of Sports Medicine.

 

World's first autonomous electric ferry

milliAmpere prototype visible at left

From New Atlas

Building bridges over municipal waterways isn't a simple or inexpensive endeavor, which is why many cities instead look to ferries. With that fact in mind, a new autonomous electric passenger ferry is being trialled in Norway, and it's said to be the first of its kind.

Designed by a team at the Norwegian University of Science and Technology (NTNU), the vessel is known as the milliAmpere 2. It's part of the university's larger Autoferry project.

In a trial project that runs until the middle of next month, it is currently transporting passengers across the main channel in the city of Trondheim. Although the craft can accommodate up to 20 passengers, it's taking a maximum of 12 at a time during the testing period. And according to NTNU, "This is the first time a self-propelled electric passenger ferry has been put into trial operation along urban waterways."

As compared to an earlier prototype (named the milliAmpere), the milliAmpere 2 is considerably larger, it sports a new design, plus it incorporates more advanced technology beneath its deck. That under-deck technology includes battery packs, chargers, computers, and a dynamic positioning system.

Up on top of the deck, sensors such as cameras, LiDAR and radar modules allow the ferry to monitor its surroundings, in order to avoid collisions with structures or other watercraft. And while it is designed to run autonomously, a human operator in a land-based control room is able to watch what it's doing via those sensors, and can take manual remote control if necessary.

The technology behind the milliAmpere 2 is being commercialized by spinoff company Zeabuz. That startup is working with Norwegian ferry company Torghatten to develop an autonomous ferry, which is slated to enter use in Stockholm, Sweden next summer.

The gorgeous Eviation electric plane

 

I've talked about Eviation's elegant and stylish electric plane before.  This report is from New Atlas

After showing off with some extravagant runway wheelies last week, Alice, the "world's first all-electric commuter aircraft," lifted off overnight on a historic first flight. It's another major milestone toward zero-emissions medium-range air travel.

Alice took off at 7.10 am local time from Grant County International Airport in Washington state, and made a short, 8-minute circuit, reaching an altitude of 3,500 ft (1,067 m) before coming in and touching down.

"Today we embark on the next era of aviation – we have successfully electrified the skies with the unforgettable first flight of Alice," said Eviation President and CEO Gregory Davis. "People now know what affordable, clean and sustainable aviation looks and sounds like for the first time in a fixed-wing, all-electric aircraft. This ground-breaking milestone will lead innovation in sustainable air travel, and shape both passenger and cargo travel in the future."

It is indeed a significant moment, although there's a way to go yet. The Alice we see flying in the video below is still an experimentally registered prototype, rather than a fully certified production aircraft. Eviation still has to run it through a full and rigorous flight test regime, and jump through the many hoops of FAA certification, not just for the aircraft and all its systems, but also for the company itself as a design organization and a production facility. The company hopes to have this all squared away and get Alice into service by 2026.

Alice's spec sheet has become a fair bit less impressive over the last year or so as well – when we looked at it in May 2021, this nine-seat luxury machine was running an interesting three-prop propulsion system and a V-tail, and promising 506-mile (814 km) flights to a charge. Now, the tail's a T-shape, there are just two props, the claimed range has dwindled to just 288 miles (463 km), and the max takeoff weight (MTOW) has burgeoned from 14,700 lb (6,668 kg) to 18,400 lb (8,346 kg). On the positive side, the max speed is now up from 253 mph (407 km/h) to 299 mph (481 km/h).

The reduced range in particular is going to sting, as it'll significantly cut down the number of operating routes Alice can handle. But Eviation says this machine's quiet, zero-emissions flight, and its extremely low operating costs compared to turboprops or light jets, will make a good case for it in the commuter and cargo markets.

"Relatively low cost" plan to cool the poles

From New Atlas

New research suggests that cooling the poles by 2 °C (3.6 °F), and re-freezing the Arctic and Antarctic, is "feasible at relatively low cost with conventional technologies," using Stratospheric Aerosol Injection (SAI) of heat-reflective particles focused on the poles. The side effects could be nasty, and the politics near-impossible, but the plan offers a way to slow, or reverse the catastrophic sea level rise projected as polar ice collapses.

SAI is an enormously controversial idea inspired by the cooling effects that tend to follow large volcanic eruptions. These natural events eject vast amounts of dust, ash, and often sulfur dioxide into the air. The first two create a shade effect that causes a short-lived cooling effect for a couple of hours, but sulfur dioxide tends to rise high into the stratosphere, where it combines with water molecules to create sulfuric acid particles, and remains for up to three years, reflecting solar radiation away and causing a long-lasting surface cooling effect.

So the idea behind SAI is to load up high-altitude aircraft with sulfur dioxide, and fly around spraying it into the atmosphere at high altitudes, mimicking the cooling effect of a volcano. So far, so good. Mind you, the way that sulfuric acid eventually leaves the atmosphere is by combining into larger and larger droplets that eventually become heavy enough to fall down to earth as acid rain, which is, as you'd imagine, not great for plant life, fish or animals. And all sulfur oxides are nasty to breathe in, harming the lungs and causing asthma and bronchitis if inhaled regularly.

To date, most SAI research and modeling has focused on spreading these aerosol deployments all over the globe. But there's a growing number of scientists starting to look into just doing it at the North and South Poles. The Arctic and Antarctic are feeling the effects of climate change far worse than the rest of the world at this stage; they're warming several times faster than the global average, causing colossal ice structures to collapse and melt. Every climate model factors in the resulting rise in sea levels, which will have catastrophic effects all over the world.

To state the obvious, no scientist wants to fill the air with sulfur, drench the last remaining polar bears and penguins in acid rain, or give carbon emitters any excuses not to clean up their act. But faced with our current trajectory, on which summer sea ice in the Arctic will more or less disappear by 2050 or earlier, humanity finds itself between a rock and a hard place. All options need to be on the table, evaluated, and to some extent ready to go early enough to make a difference.

So research into SAI is progressing quickly, and concentrating it at the poles – an approach referred to as subpolar deployment – may deliver better returns for significantly less money and acid rain than a global model. Prior research has indicated that spring and early summer is likely the most effective season to do it, and that only doing this at one pole could have asymmetrical effects on global weather, so it's probably prudent to target both, with a fleet of planes that travels with the seasons.

A new study from a fairly broad range of contributors digs into what a bipolar SAI program targeted at "refreezing" the Arctic and Antarctic might look like, what it'll cost, and where the equipment and technology gaps might be.

The study proposes a nominal target of cooling the North and South Poles by 2 °C (3.6 °F), noting that Arctic temperatures have already risen by more than 3 °C (5.4 °F) over the last 50 years. It proposes that the aerosol injections be made at the 60th parallels, roughly the latitudes of Oslo, Helsinki, Homer, Alaska and Magadan, Siberia in the Northern Hemisphere, and level with the southern tip of Patagonia in the Southern Hemisphere. At these latitudes, it's possible to get the job done cheaper, since the troposphere sits at a lower altitude and your aircraft don't have to fly so high. This study chooses an altitude of 13 km (42,600 ft). The particles released would drift slowly toward the poles, concentrating their effects.

To achieve a 2 °C result, the plan would inject 6.7 teragrams (6.7 billion kg/14.8 billion lb) of sulfur dioxide per year into each pole, calling for an eye-watering total of 13.4 teragrams (29.5 billion lb) of material annually.

The study goes on to look at logistics, finding that existing aircraft can't carry enough payload to a sufficient height to get the job done. The closest we've currently got are military air-to-air refueling aircraft, but these can't reach the target altitudes without significantly reducing their payloads. The McDonnell Douglas KC-10 Extender, for example, could get up into the spray zone carrying some 128,801 lb (58,400 kg) of payload, but that's just 22% of the payload it's designed to carry, so you'd be carrying a lot of excess weight on every flight.

The study proposes instead a purpose-built stratosprayer called the SAIL-43K, a downgraded version of an aircraft previously specified to fly higher SAI missions closer to the equator. This machine would carry 167,971 lb (76,190 kg) of payload each mission, but its takeoff weight would be some 77,000 lb (35,000 kg) lighter than the KC-10.

To hit the cooling target, this project would need 125 purpose-built SAIL-43Ks, flying a total of 1,458 missions per day during the four-month injection period at each pole. These planes would take off, climb for 30 minutes, vent their entire load of sulfur dioxide within two minutes, then come back down over the following 30 minutes, and spend the next hour loading up again and refueling for the next mission.

In the Northern Hemisphere, there are plenty of airfields suitable for these kinds of operations; virtually the whole 60th parallel falls on land. In the south, things get a bit more fraught as there are really only a few airfields in Southern Patagonia with appropriate runways. These sit at latitudes closer to 54°, but the team calculates they'll get better results just venting the sulfur dioxide at that latitude than flying some 490 nautical miles south to hit 60°.

These airports would need to be upgraded to handle a total of 110 operations per hour, or a little more than the world's busiest current airport – this will be an enormous undertaking in the Southern Hemisphere, since there are so few airfields to start with in Patagonia. This huge infrastructure job would likely take about as long as developing and manufacturing 125 aircraft – about 15 years after making a decision to go ahead with the plan. This, in itself, is hardly a quick or complicated part of the process, and would require some degree of global agreement on a plan that would disproportionately affect people living in the latitudes in question.

In terms of money, the "relatively low cost" of this project would be around US$11 billion a year (2022 dollars), says the team. This might sound like a lot, but it's about a third of the price of a global SAI effort with the same cooling target, and the researchers note that "relative to other possible strategies by which to combat either the impacts or causes of climate change, SAI remains extraordinarily inexpensive."

While calibrated to drop polar temperatures by 2 °C and to begin re-freezing sea ice at the poles, this project will have a number of unwanted side-effects. The researchers note that the sulfur compounds added to the stratosphere may impact ozone concentrations through a number of different effects, and may thus slow or reverse the recovery of the Antarctic ozone hole. It notes that the effects of teragrams of sulfur dioxide and the associated acid rain deposits are risky both to humans and to the wider ecosystem, requiring lots more research. And it expects some stratospheric heating as well.

Furthermore, the planes themselves can only operate by burning jet fuel, using today's technologies. This annoying fact, plus the emissions involved in building out all the required infrastructure on the ground, plus the emissions involved in preparing sulfur dioxide, mean that a polar SAI program would have a pretty damn hefty carbon footprint of its own, although this would only represent a "marginal" increase to overall aviation sector emissions.

Still, the researchers conclude that "while it has yet to be established that the physical or societal impacts of any SAI program would prove to be net positive, it seems clear that a program focused on substantially cooling the world's polar and subpolar regions would be logistically feasible. This could arrest and likely reverse the melting of sea ice, land ice, and permafrost in the most vulnerable regions of the Earth's cryosphere. This in turn would substantially slow sea level rise globally."

So, short answer: yes, we can re-freeze the poles, while minimizing the risk to the bulk of humanity and agriculture. But we'd need the entire world to agree that sea level rise is a worse outcome than the effects of a massive SAI program, especially for the estimated 1% of the population that lives in the areas where the effects will be concentrated.

"There is widespread and sensible trepidation about deploying aerosols to cool the planet," says Wake Smith, lead author of the new study, in a press release. "But if the risk/benefit equation were to pay off anywhere, it would be at the poles. Game changing though this could be in a rapidly warming world, stratospheric aerosol injections merely treat a symptom of climate change but not the underlying disease. It's aspirin, not penicillin. It's not a substitute for decarbonization."

The study is open access in the journal Environmental Research Communications.

Source: Institute of Physics via Phys.org

Mankind has dithered and delayed so long in acting on climate change that there are now no safe methods to undo the damage.   The fact that we even have to think about it is an indictment of those denialists who, obedient to their fossil fuel paymasters, have so poisoned the well that we've delayed decades before acting.  And remember, emissions are still rising.  Temperatures are still rising.  It's not getting better.