The concrete industry accounts for roughly 8 percent of global carbon dioxide emissions, but a new study says that it could one day be a source of negative emissions. By taking a page out of nature's playbook, scientists at Northwestern University developed a carbon-negative concrete through a process similar to how mollusks form their shells. This technique further builds on the laboratory's work, which involves using electric currents to solidify areas impacted by coastal erosion. Adopted by 196 countries (including the flip-flopping United States), the 2016 Paris Climate Agreement set an ambitious goal for the world's economies to be carbon neutral by the year 2050. While that in itself is an immense political and engineering challenge, the true goal of creating a sustainable planet for future generations and the millions of species on Earth is to develop carbon-negative technologies. These breakthroughs not only help limit the production of harmful CO 2 gasses from escaping into the atmosphere, they actively remove greenhouse gasses already wreaking havoc across the planet. These techniques often involve siphoning carbon from the atmosphere to create a valuable end product that, one way or another, traps that carbon for decades to come. Now, scientists from Northwestern have looked to the shell-building attributes of mollusks and coral to develop a method for creating carbon-negative concrete. By applying an electric current to seawater and then bubbling CO 2 gas into that water, Alessandro Rotta Loria—civil and environmental engineer…