The desert planet Arrakis from Frank Herbert's science fiction novel Dune is plausible, says Alexander Farnsworth, a climate modeler at the University of Bristol. According to Science News, the world is a harsh place for humans to live, and we probably don't have to worry about being eaten by extraterrestrial worms. From the report: For the Arrakis climate simulation, which can be explored on the website Climate Archive, Farnsworth and his colleagues started with the well-known physics that governs weather and climate on Earth. Farnsworth said it made sense to use Earth as a starting point, as Herbert drew inspiration for Arrakis from “a kind of semi-science of looking at the dune system of Earth itself.” The team then added nuggets of information about the planet from Herbert's novels and details from the Dune Encyclopedia. According to that information, this fictional planet's atmosphere is similar to Earth's, but with some notable differences. Arrakis has less carbon dioxide in its atmosphere than Earth, with concentrations of carbon dioxide on Earth at 417 ppm, compared to about 350 ppm on the desert planet. However, there is much more ozone in Dune's lower atmosphere, making up 0.5 percent of the gas in the atmosphere, compared to Earth's 0.000001 percent.
All that extra ozone is critical to understanding our planet. Ozone is a powerful greenhouse gas, about 65 times more capable of warming the atmosphere than carbon dioxide when measured over a 20-year period. “Even though it has less carbon dioxide than Earth does today, Arrakis' atmosphere would certainly be warmer,” Farnsworth said. In addition to global warming, the presence of large amounts of ozone in the lower atmosphere could be bad news. “I think it would be incredibly toxic and almost fatal for humans to live under those conditions,” Farnsworth says. The people of Arrakis will likely have to rely on technology to remove ozone from the air. Of course, ozone in the upper atmosphere could help protect Arrakis from harmful radiation from its star Canopus. (Canopus is a real star, also known as Alpha Carinae. It is visible in the southern hemisphere and is the second brightest star in the sky. Unfortunately for Dune fans, it is not known to have a planet.) ) If Arrakis were real, that's what it would be. Farnsworth said it's about the same distance from Canopus as Pluto is from the sun. However, Canopus is a large white star whose temperature is calculated to be about 7,200 degrees Celsius. “This is much hotter than the sun,” Farnsworth said. But “there are a lot of guesses and assumptions that they've made here, and we don't know if those are accurate numbers.”
Climate simulations reveal that Arrakis is probably not as described by Herbert. For example, in a throwaway line, the author explains that the polar ice caps are retreating due to the summer heat. But Farnsworth and his colleagues say the polar regions would be too hot for ice sheets to exist, with summer temperatures of around 70 degrees Celsius. Additionally, there is too little precipitation in winter to replenish the ice. Upper-level clouds and other processes will warm the polar atmosphere, keeping it warmer than lower latitudes, especially in the summer. Herbert's novels have people living in mid-latitudes and near the poles, but the intense summer heat and bone-chilling winter temperatures of -40 to -75 degrees make these regions nearly uninhabitable without technology. Probably, Farnsworth said. The temperature in the tropical latitudes of Arrakis is relatively comfortable, with the warmest months at 45°C and the coldest months around 15°C. On Earth, the tropics are much warmer than the polar regions due to higher humidity. But on Arrakis, “most of the atmospheric moisture has essentially been removed from the tropics,” making it able to withstand scorching summers. Clouds and trace amounts of moisture collect at the poles, heating the atmosphere. But the tropics of Arrakis pose its own challenges. Researchers calculate that hurricane-force winds would regularly sandblast residents and build sand dunes 250 meters high. That doesn't mean people can't live on Arrakis, Farnsworth says, just that they'll need technology and lots of extraterrestrial help to bring food and water. “I think this world is a very livable world, but I also think it's a very difficult world to live in.''