A federal agency is in the first phase of a project to curb human-caused undersea noises that experts worry could be affecting ocean mammals. The National Oceanic and Atmospheric Administration's project is looking to document noises across the globe to generate one of the first large-scale sound maps. The sea spans more than 70 percent of the Earth's surface, making the project a major undertaking. So far, dozens of the ocean visualizations have been made public. The maps use bright colors to depict the annual average noise that permeates through the waters in particular areas.