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Carbon dioxide gets most of the blame for rising global temperatures, but it’s only one of several culprits, the list of which now turns out to include microplastics – but only as a minor player.
A group of researchers from China and the United States published a paper in Nature yesterday that contradicts previous findings that sunlight absorption by microplastics wouldn’t be a significant problem. That earlier research focused on uncolored plastics, but this study’s authors found that much of the plastic in our actual atmosphere is colored, and therefore more prone to heating up in the sun.
The team argues that atmospheric science needs to be updated to account for this new vector of climate change. But although it’s true that models need to be as precise as possible, that doesn’t mean climate change is much worse than we thought.
Direct absorption of sunlight is only the secondary driver of climate change. Even within that category, microplastics pale — literally and figuratively — to other contributors like plain old soot. Based on the team’s simulations, microplastics might be at most a few percent of the overall problem.
Albedo Changes vs. Trapping
Fundamentally, climate change is a function of how much of the incoming solar radiation ends up staying with Earth, versus being reflected or re-emitted back into space.
Carbon dioxide in the atmosphere accounts for an estimated 80% to 90% of the recent change in retention over the earlier baseline. However, it works in a slightly complicated way. It’s transparent to visible light, which is why you can’t see it. So, it doesn’t do anything to the sunlight as it comes in.
However, all things radiate away their heat in the form of light, whose wavelength depends on the object’s temperature. In the case of objects at typical Earth surface temperatures, those wavelengths are in the infrared. Unfortunately, carbon dioxide is opaque to infrared light. So, the sunlight comes in, but the outgoing infrared gets trapped and heats up the carbon dioxide instead of flying harmlessly out into space.
The more direct causes involve changes in the Earth’s albedo, which is physicist-speak for “whiteness” or “shininess.” Just like black asphalt gets hotter on a summer day than the paler sidewalk, any darkening of the Earth’s tint will make it ever-so-slightly warmer.
The biggest contributor to global warming after carbon dioxide is so-called black carbon, which means tiny specks of soot and smoke. However, colored microplastic dust now appears to be a small but not-insignificant contributor. Even the white stuff isn’t harmless; the team found that its gradual yellowing almost exactly offset the bleaching of darker plastics in their samples, keeping the overall light absorption constant.
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Quantum ‘Thermometers’ Probe Interior of Cancer Cells
Applications for quantum physics in the medical field may soon become more numerous, thanks to practical advances in nanoscale engineering. Japanese researchers have achieved a proof-of-concept for molecular-scale sensors that with three important properties: they function at room (or body) temperature, they can be dispersed through water, and they can penetrate living cells without harming them.
They demonstrated the technology on cancer cells, measuring a temperature difference of about one degree Celsius between the cell’s nucleus and the surrounding cytoplasm.
More ‘Circumbinary’ Planets Discovered
Planets orbiting binary stars are rare, but not non-existent, and the number of them we know about has just increased 150%. The Transiting Exoplanet Survey Satellite, with some help from AI, recently added 10,000 new planets to our map of the Universe, and 27 of those turn out to be in binary systems.
The reason that such finds are rare is that a two-star system produces chaotic planetary orbits. In most cases, that means a planet would eventually collide with one of the stars and cease to be a planet. However, for certain configurations, the orbit is only chaotic within a limited band that doesn’t include such collisions. Even then, the unusual orbits would lead to extreme and hostile planetary environments, as popularized through the novel and televised series The Three-Body Problem.
When Adolescent Trauma Snowballs, Conspiracy Theories Result
Many teenagers report feelings of victimhood through bullying and other markers of “shattered safety,” yet typically these diminish over time. A team of researchers from the University of Zürich found that when that doesn’t happen, those feelings will instead snowball over time and correlate with higher rates of belief in conspiracy theories, extreme political views, and even violence.
The “shattered safety” hypothesis posits that children instinctively assume that the world is fair, that most other people are trustworthy, and that they themselves are good and deserve to be treated well. Through a longitudinal study, the team found that many youths grow up with those beliefs intact or successfully cope with the trauma of having them shattered. However, when the intensity of that loss of trust didn’t decrease with time, it instead increased — they found no evidence of mistrustfulness remaining high but constant.
For those whose mistrust escalated into adulthood, it was often externalized into a paranoid worldview, feeding into conspiracy theories and extremist politics.
