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       Here’s another crazy proposal on the list of fantastical but extremely interesting geoengineering solutions to climate change: coating young Arctic sea ice with a layer of reflective glass powder.
       The blinding white color of Arctic sea ice not only adds drama to one of the most dynamic climates on Earth; it actually acts like a giant sunglass, reflecting the sun’s rays back into space.
       According to the National Snow and Ice Data Center, Arctic sea ice reflects more than 80 percent of the sunlight that hits its surface, which helps keep the poles cool. The National Oceanic and Atmospheric Administration says cooler temperatures at the poles will affect global climate, and shrinking ice caps will also change ocean currents.
       When that bright white begins to melt (and continues to melt), darker water takes its place, absorbing more sunlight and warming the ocean—until the Arctic sea ice disappears and the world changes irreversibly.
       ”We’re trying to break the feedback loop and start rebuilding,” Leslie Field, an engineer at the non-profit Arctic Ice Project, told the BBC.
       Arctic sea ice accumulates over years to turn sunscreen white; young ice is thinner and darker, and the ocean is visible through the slushy surface. This ice absorbs more sunlight and melts, preventing the ice from returning.
       According to the BBC, Field’s idea was simple in concept but complex in execution. Reflective materials sprinkled on young Arctic sea ice can deflect enough sunlight to allow the ice to survive the summer, continue to form, and ultimately help rebuild the reflective cap.
       In a paper and presentation presented at the 2019 fall meeting of the American Geophysical Union, Field estimated that implementing this technology throughout the Arctic could increase sea ice concentrations by 15-20% and reduce temperatures across much of the Arctic by 1.5°C.
       Field chose silica, which occurs naturally in sand and is used to make glass. According to the BBC, Field found a company that made tiny, hollow beads that were thinner than a human hair and designed to float (though some inevitably sank).
       For the past decade, Field has been spreading silica powder on lakes and ponds in Canada and the United States. There have been some positive results: In Minnesota, a layer of powder increased the reflectivity of pond ice by 20 percent.
       Field’s plan is to use microsilica only in certain areas with a high risk of rapid melting – the BBC has named the Fram Strait near Greenland as a potential target. (Sorry, as cool as the sea of ​​glass is, it’s not the end.)
       However, geoengineering always carries risks. Some of them are obvious: What happens if animals ingest silica? Field told BCC that since silica is already widespread in nature, it should be safe for animals.
       The size of the balls is similar to some plankton food sources, Karina Giesbrecht, an ecologist at the University of Victoria, told the BBC. Plankton may unintentionally eat them, unintentionally starving themselves.
       ”If you put silica globules in an area with fast ocean currents, especially the Fram Strait, they will dissipate very quickly,” Mark Serreze, a climate scientist at the US National Snow and Ice Data Center, told the BBC.
       This is certainly an ambitious solution, as is customary in geoengineering. But in terms of plausibility, reflective silicon powder on Arctic sea ice is closer to the former than carbon capture to stellar engines.