How Termination Shocks Could Intensify the Economic Impact of Climate Change

Solar geoengineering: A solution to save ice sheets with potential risks

Credit: Martin Zwick/REDA/Universal Images Group (via Getty Images)

Research indicates that an abrupt halt to solar geoengineering may lead to a “termination shock,” causing a rapid temperature rise that could make the initiative more expensive than continuing without intervention.

With greenhouse gas emissions on the rise, there’s increasing attention on solar radiation management (SRM), which cools the planet by dispersing sulfur dioxide aerosols into the stratosphere to reflect sunlight.

However, sustained solar geoengineering is crucial for centuries; otherwise, the hidden warming could quickly reemerge. This rebound, referred to as termination shock, leaves little time for adaptation and could catalyze critical climate events such as ice sheet collapses.

According to Francisco Estrada, researchers from the National Autonomous University of Mexico assessed the risk of inaction on climate change compared to solar geoengineering approaches.

Projections suggest that if emissions aren’t curtailed, temperatures may soar by an average of 4.5 degrees Celsius above pre-industrial levels by 2100, leading to approximately $868 billion in economic damages. In contrast, a hypothetical stratospheric aerosol injection program initiated in 2020 could limit warming to around 2.8°C, potentially reducing these costs by half.

Nevertheless, if the aerosol program ends abruptly in 2030, resulting in a temperature rebound of 0.6 degrees Celsius over eight years, economic damages could surpass $1 trillion by century’s end. While estimations vary, Estrada states, “The principle remains consistent: the termination shock will be significantly worse than inaction.”

Estrada’s research innovatively gauges damage not only by global warming levels but also by the speed at which temperatures rise, according to Gernot Wagner from Columbia University.

Wagner warns that solar geoengineering may be riskier than it appears. “This highlights a critical concern,” he notes.

Make Sunsets, a Silicon Valley startup, has already launched over 200 sulfur dioxide-filled balloons into the stratosphere and offers emission offsets for sale. A recent launch in Mexico prompted governmental threats to ban geoengineering activities.

Israel’s Stardust Co., Ltd. has secured $75 million in funding and is lobbying the U.S. government to explore solar geoengineering options. A recent survey revealed that two-thirds of scientists anticipate large-scale SRM could occur this century, as reported by New Scientist.

According to studies, it would take at least 100 aircraft to cool the Earth by 1°C through aerosol injection, releasing millions of tons of sulfur dioxide annually, unimpeded by geopolitical conflicts or unforeseen events.

Presently, major nations like the United States are undermining global climate cooperation, but researchers highlight that such collaboration is essential to prevent termination shock and potentially realize the benefits of SRM.

Analysis of varying parameters suggests that aerosol injections could mitigate climate damage only if the annual probability of cessation is extremely low. In scenarios allowing for a gradual stop over 15 years, SRM might be viable.

If countries successfully reduce emissions, only minimal geoengineering cooling may be necessary, rendering aerosol injection beneficial with a maximum outage probability of 10%. This indicates a potential 99.9% chance of failure over a century, but manageable temperature recovery remains plausible in low emissions scenarios.

This need for international cooperation reveals what Estrada describes as the “governance paradox” of solar geoengineering: “We must ensure extremely low failure rates and possess effective governance to mitigate adverse outcomes.” However, he adds, “If we effectively reduce greenhouse gases, the need for SRM diminishes.”

These findings challenge the notion that solar geoengineering might lead to irresponsible development, as some have suggested, according to Chad Baum from Aarhus University. Funding for this new research was provided by the Degrees Initiative, aimed at supporting geoengineering studies in vulnerable low-income nations.

Baum stated, “We intend to complete all stages of this study, incorporating feedback from impacted communities.”

Despite this, Wagner emphasizes the imperative for further exploration into geoengineering’s trade-offs given the rise in emissions and their consequences: “We are approaching a critical juncture.”

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Source: www.newscientist.com

3I/ATLAS Comet Awakens: Signs of Activity Intensify Post-Perihelion

NASA’s SPHEREx mission reveals that interstellar object 3I/ATLAS dramatically transformed into an active comet following its close approach to the Sun.



SPHEREx imaging of 3I/ATLAS taken from December 8th to 15th, 2025. Image credit: NASA / arXiv: 2601.06759.

SPHEREx monitored 3I/ATLAS from December 8 to 15, 2025, shortly after its perihelion, the closest approach to the Sun.

“In December 2025, SPHEREx reobserved 3I/ATLAS post-perihelion and found it to be far more active than previously observed. August 2025 SPHEREx pre-perihelion observations show significant evidence that it has completely sublimated its ice, transforming into a comet,” explained astronomer Carrie Risse from Johns Hopkins University Applied Physics Laboratory.

New SPHEREx data indicates a gas- and dust-rich coma, revealing emissions of cyanide (CN), water (H2O), organic compounds (CH), carbon dioxide (CO2), and carbon monoxide (CO).

“The emergence of cyanide and organic matter indicates their presence in the aqueous phase,” said Avi Loeb, a Harvard University professor not involved in this study.

Researchers noted a sharp increase in water activity, accompanied by a significant surge in carbon monoxide emissions.

“The H2O gas signature, previously nearly undetectable in August, is now 20 times stronger, indicating complete sublimation of water,” added the researchers.

“CO emission rates have increased by 20 times, as the CO/CO2 ratio has risen 15-fold as well.”

SPHEREx images further demonstrate that the object’s gaseous envelope has expanded significantly.

“The gas comas observed by SPHEREx are distinctly resolved, extending from 1 foot to 3 feet in radius; all but the CN and CH organic comas appear round relative to the Sun and orbital velocity,” scientists noted.

“In contrast, the dust and organic matter images in the SPHEREx continuum exhibit a pear-shaped morphology, with the ‘pear stalk’ directed toward the Sun.”

“These varying shapes suggest that CN and CH are sourced from dust, while H2O, CO2, and CO gases are distributed symmetrically around the atomic nucleus.”

“No visible jets or anti-solar tail structures were detected.”

SPHEREx’s observations indicate fundamental changes in the physical state of 3I/ATLAS.

“December 2025’s observations align with a comet that is fully active and sublimating water ice,” the authors concluded.

The composition now resembles that of typical Solar System comets, with ice content comparable to most comets.

Researchers attribute these changes to the object’s trajectory through the inner solar system.

“By December, 3I/ATLAS had spent 3.5 months within the solar system’s ice line, causing all comet components and volatile CO2 ice to become active,” they stated.

“Consequently, the bulk material of the cometary matrix evaporated, releasing its contents.”

“Further observations are anticipated before 3I/ATLAS passes through SPHEREx’s investigation pattern again in April 2026,” they concluded.

For more information, refer to their paper, submitted for publication in AAS Research Notes.

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CM Lisse et al. 2026. SPHEREx reobservations of interstellar object 3I/ATLAS in December 2025: increased post-perihelion activity, detection of coma dust, and new gaseous emissions. RNAAS submitted for publication. arXiv: 2601.06759

Source: www.sci.news

How Menstruation Can Intensify Sports Injuries

goal! Researchers examined the FC Barcelona women’s team players

Eric Alonso/Getty Images

The notion of tailoring lifestyle habits according to the phases of the menstrual cycle is gaining momentum both in scientific fields and on social media. Recent studies indicate that when athletes incur sports injuries during their menstrual periods, recovery times are notably extended compared to other cycle stages.

#cyclesyncing has been widely featured across social media, advocating for adjustments in both dietary choices and physical activity based on the fluctuations in hormones throughout the menstrual cycle. However, the scientific backing for these dietary modifications remains limited, while research regarding exercise provides mixed results. Still, teams such as the American and British rugby squads have already adapted their training to align with players’ menstrual cycles.

To investigate this further, Eva Ferrer and her team at Sant Joan de Deu Hospital in Barcelona monitored 33 professional athletes from FC Barcelona’s women’s team over a four-season span from 2019 to 2023.

During their standard training routines, the athletes documented their menstrual cycle days. All injuries sustained during the season were classified by severity by medical professionals applying a standardized assessment scale.

The findings revealed that while the athletes did not experience injuries specifically during their menstrual days, those incurred during this period appeared to be more severe. For instance, soft tissue injuries sustained while menstruating led to over three times the duration of training lost compared to injuries incurred at other times.

These outcomes may be influenced by decreased estrogen levels during menstruation. This hormone is vital for muscle recovery and rehabilitation. “The combination of reduced estrogen, potential iron depletion, increased symptom severity [like cramps], and heightened fatigue during this phase can negatively affect injury recovery,” notes Ferrer.

However, Stuart Phillips from McMaster University in Canada emphasizes that the intricacies of estrogen’s role in muscle repair remain unclear. “Estrogen is believed to offer protective and reparative qualities [for muscles],” he states, “but much of this evidence derives from animal studies rather than human experiments.” Furthermore, their study did not account for possible confounding variables like women’s iron levels or fatigue.

Ferrer acknowledged that while they recorded a total of 69 injuries on non-bleeding days, only 11 occurred during menstruation. “When you overlook sample sizes and confidence intervals, a small number of critical injuries can distort the overall results,” she explains. Additionally, it remains uncertain if these findings are applicable to less competitive athletes or casual sports participants, according to Ferrer.

She hopes that future research will elucidate these issues and possibly lead to exercise recommendations tailored to various menstrual cycle stages. “The most prudent approach is to make individualized decisions regarding training loads and types of exercise during menstruation. Ongoing research will consider each athlete’s symptoms alongside objective data (internal and external workload, injury histories, health metrics, etc.), while also integrating hormone measurements, iron levels, sleep patterns, nutrition, and other factors that may enhance these recommendations,” Ferrer asserts.

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Source: www.newscientist.com

AI Could Intensify Racism and Sexism in Australia, Warns Human Rights Commissioner

Concerns have been raised that AI could exacerbate racism and sexism in Australia, as human rights commissioners expressed during internal discussions within the Labor party regarding new technologies.

Lorraine Finlay cautioned that while seeking productivity gains from AI is important, it should not come at the cost of discrimination if the technology remains unregulated.

Finlay’s remarks came after worker Sen. Michel Ananda Raja advocated for the “liberation” of Australian data to tech companies, noting that AI often reflects and perpetuates biases from abroad while shaping local culture.

Ananda Raja opposes a dedicated AI law but emphasizes that content creators ought to be compensated for their contributions.

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Discussions about enhancing productivity through AI are scheduled for the upcoming federal economic summit, as unions and industry groups voice concerns over copyright and privacy issues.

Media and Arts organizations have raised alarms about the “ramping theft” of intellectual property if large tech corporations gain access to content for training AI systems.

Finlay noted the challenges of identifying embedded biases due to a lack of clarity regarding the datasets used by AI tools.

“Algorithmic bias means that discrimination and inequality are inherent in the tools we utilize, leading to outcomes that reflect these biases,” she stated.




Lorraine Finlay, Human Rights Commissioner. Photo: Mick Tsikas/AAP

“The combination of algorithmic and automation biases leads individuals to rely more on machine decisions and potentially disregard their own judgment,” Finlay remarked.

The Human Rights Commission has consistently supported an AI Act that would enhance existing legislation, including privacy laws, and ensure comprehensive testing for bias in AI tools. Finlay urged the government to quickly establish new regulations.

“Bias tests and audits, along with careful human oversight, are essential,” she added.


Evidence of bias in AI technologies is increasingly reported in fields like healthcare and workforce recruitment in Australia and worldwide.

A recent survey in Australia revealed that job applicants interviewed by AI recruiters faced potential discrimination if they had accents or disabilities.

Ananda Raja, a vocal proponent for AI development, noted the risks of training AI systems using exclusively Australian data, as well as the concerns of amplifying foreign biases.

While the government prioritizes intellectual property protection, she cautioned against limiting domestic data access, warning that Australia would be reliant on overseas AI models without adequate oversight.

“AI requires a vast array of data from diverse populations to avoid reinforcing biases and harming those it aims to assist,” Ananda Raja emphasized.

“We must liberate our data to better train our models, ensuring they authentically represent us.”

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“I am eager to support content creators while freeing up data, aiming for an alternative to foreign exploitation of resources,” Ananda Raja stated.

She cited AI screening tools for skin cancer as examples where algorithmic bias has been documented. To combat bias and discrimination affecting specific patients, it is essential to train these models on diverse datasets to protect sensitive information.


Finlay emphasized that any release of Australian data needs to be handled fairly, but she feels the emphasis should be on establishing appropriate regulations.

“It’s certainly beneficial to have diverse and representative data… but that is merely part of the solution,” she clarified.

“We must ensure that this technology is equitable and is implemented in a manner that recognizes and values human contributions.”

Judith Bishop, an AI expert at La Trobe University and former data researcher at an AI firm, asserted that increasing the availability of local data will enhance the effectiveness of AI tools.

“It is crucial to recognize that systems developed in different contexts can be relevant, as the [Australian] population should not exclusively depend on US data models,” Bishop stated.

eSafety Commissioner Julie Inman Grant has also voiced concerns regarding the lack of transparency related to the data applied by AI technologies.

In her statement, she urged tech companies to be transparent about their training datasets, develop robust reporting mechanisms, and utilize diverse, accurate, and representative data for their products.

“The opacity surrounding generative AI’s development and deployment poses significant issues,” Inman Grant remarked. “This raises critical concerns about the potential for large language models (LLMs) to amplify harmful biases, including restrictive or detrimental gender norms and racial prejudices.”

“Given that a handful of companies dominate the development of these systems, there is a significant risk that certain perspectives, voices, and evidence could become suppressed or overlooked in the generated outputs.”


Source: www.theguardian.com

Study finds air pollution may intensify summer thunderstorms

Researchers from James Madison University conducted a comprehensive study of thunderstorm environments in two distinct geographic regions: Washington, DC, and the Kansas City metropolitan area.

Air pollution is increasing the intensity of summer thunderstorms. Image courtesy of ELG21.

Land cover and atmospheric boundary layer characteristics modify thunderstorms and their characteristic phenomenon: lightning.

The most intense thunderstorm contrasts on Earth occur along continental and oceanic boundaries.

Generally, lightning strikes land at an order of magnitude more than it strikes sea.

The thermodynamic properties of the atmosphere vary significantly with different land covers over the Earth’s surface.

“Pollutants act as cloud nuclei,” said Mace Bentley, a professor at James Madison University and lead author of the study.

“Updrafts carry them into the clouds, and the updrafts and downdrafts separate the polluting particles, dispersing the electrical charges in the clouds and encouraging lightning to form.”

For the study, the authors surveyed nearly 200,000 thunderstorm events in the Washington, DC, area and more than 300,000 in the Kansas City area.

Using 12 years of lightning data from the National Lightning Detection Network and data from hundreds of air pollution monitoring stations in two cities, they found that in highly volatile environments, increased pollution increases the frequency of anti-ground lightning strikes.

“Our analysis identified a total of 196,836 thunderstorm events in the Washington DC area, while 310,209 thunderstorms were identified from the Kansas City lightning database,” the researchers said.

“In Washington, DC and Kansas City, more than 37.7% and 39.2% of all thunderstorm events, respectively, consisted of 10 or more flashes.”

“Evidence suggests that thunderstorm environments during mild warm-season synoptic weather are substantially different in terms of thermodynamics, aerosol properties, and aerosol concentrations in the Washington, DC, and Kansas City regions,” the researchers added.

“However, thunderstorm intensity, as measured by flash counts, appears to be controlled by similar thermodynamic and aerosol relationships despite differences in the surrounding environments.”

“When we look at the environments in which thunderstorms occur, we find a statistically significant positive correlation between convective available potential energy and the number of lightning events.”

“Aerosol concentration also appears to be a more important quantity than particle size when it comes to lightning enhancement.”

Scientists are now conducting a similar study in Bangkok, Thailand, a megacity that is more polluted than Washington, DC, or Kansas City and sits in a hot, tropical climate.

The results so far are similar, but these storms are showing a higher incidence of lightning.

“It appears that urban pollution can enhance thunderstorms and lightning wherever you go in the world,” Prof Bentley said.

of study Published in a journal Atmospheric Research.

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Mace Bentley others2024. Towards elucidating the relationship between thunderstorms and aerosols: An observational study centered on Washington, DC and Kansas City, Missouri. Atmospheric Research 304: 107402; doi: 10.1016/j.atmosres.2024.107402

Source: www.sci.news