Nearly 200,000 different kinds of viruses swirl in the world’s oceans, according to a new study, Quanta Magazine reports. The new count is 12 times higher than what the previous census of marine viruses recorded in 2016. The reasons for the jump, researchers says, include extensive expeditions to collect samples and improved tools for genetic analysis. Roughly 90% of the viruses identified were new to science, they report today in Cell. This new appreciation of the viral diversity of the seas could help clarify the role of such microbes in the ocean’s carbon cycle, where they can kill or manipulate bacteria that might otherwise capture or release carbon dioxide from the atmosphere.