January 15, 2025: What's behind some cold snaps, the problem with quantum systems, and a new lunar lander launched this morning. —Andrea Gawrylewski, Chief Newsletter Editor | | | An illustration of a private U.S. lander, built by Texas-based company Firefly Aerospace, on the surface of the moon. NASA/Dave Ryan | | | • Early this morning, Blue Ghost, a lunar lander built by the Texas-based company Firefly Aerospace, launched atop a SpaceX Falcon 9 rocket. | 7 min read | • Solitary migrating songbirds seem to cooperate across species and possibly share information during nighttime migrations. | 3 min read | | | January 31, 2019, in New York City. Johannes Eisele/AFP via Getty Images | | | On balance, global temperatures are warming up. But that doesn't mean that cold snaps don't happen. January so far has been colder on average in most of the U.S. east of the Rocky Mountains, according to data from the Prism Climate Group at Oregon State University. Some cold snaps occur when frigid air from the Arctic gets pulled southward as a result of two atmospheric phenomena.
How it works: Usually, the polar jet stream circulates at about 50 to 60 degrees latitude, keeping cold air near the Arctic, and warmer air at more southern latitudes. A second atmospheric phenomenon, dubbed the "polar vortex" circulates more than 10 miles above Earth's surface, and strengthens during the Northern Hemisphere's coldest months. Sometimes the polar vortex can destabilize and nudge the polar jet stream to meander away from its usual path, bringing bitter cold south.
What the experts say: Cold extremes have become more frequent since 2000, when the Arctic's warming rate picked up steam, says Judah Cohen, a climate scientist at the company Atmospheric and Environmental Research. Although scientists are still investigating why, what IS certain is that winters, overall, are getting warmer and extremes will continue to become more common. | | | When scientists measure a quantum system, the system's many possible states will randomly collapse into just one—the one that we observe post-measurement. The trouble is, no one agrees on what constitutes a "measurement" exactly. This so-called "measurement problem" leads to bizarre outcomes that strike at the heart of our understanding of reality—two observers won't necessarily see the same outcome from a quantum interaction. To better understand this attack on objectivity (what physicists call "absoluteness"), a recent study catalogs how the measurement problem arises in the first place and ways to avoid the problem so that absoluteness is preserved.
Why this matters: Sidestepping the measurement problem, it turns out, may require a radical rethinking of quantum theory. For example, one possible theory that maintains absoluteness is the Ghirardi-Rimini-Weber theory (GRW), which posits that quantum systems collapse independently (with or without an observer), and the final state is the same for all observers. This theory replaces measurement with random system collapses that yield quantum outcomes.
What the experts say: "It's a demonstration that there is no pain-free solution to this problem," says Nicholas Ormrod, a physicist at the University of Oxford. "If we ever can recover absoluteness, then we're going to have to give up on some physical principle that we really care about." | | | • Two simple reforms would provide the tech industry access to global talent while minimizing job losses of domestic workers, writes Hal Salzman, a professor of policy and workforce development at Rutgers University. "First, guest worker visas, including H1-Bs, should be issued only for workers paid in the top 15 percent of each industry and occupation groups' wages," he says. Second, work visas should go only to graduates in the top 15 percent of each class for workers entering through optional practical training programs that provide work permits to foreign students. | 5 min read | | | • Charred material and sediment from the California fires is flowing into the waterways and threatening the endangered steelhead trout that live in the Santa Monica Mountains. | L.A. Times | • The members of the Food and Drug Administration's vaccine advisory committee are the true vaccine skeptics. RFK Jr. is a vaccine cynic, who refuses to acknowledge science. | The New York Times | | | • Urban fires will continue to become more common. Firefighting will barely be able to keep up. | The Atlantic | | | Climate scientists have conducted hundreds of studies in the last 20 years with the specific aim of determining how much a changing climate contributes to extreme weather events. Overall, the takeaway is that in more than 70 percent of weather events, climate change made the situation worse. This includes events of extreme COLD weather. It seems counterintuitive, but (among other effects) warming oceans release more moisture into the atmosphere through evaporation, and that can change weather patterns around the globe. Even cold weather. Climate change is much more than warming. | —Andrea Gawrylewski, Chief Newsletter Editor | | Subscribe to this and all of our newsletters . | | | | Scientific American
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