The interdependence of humans and our natural environment is at the heart of scientific literacy in the Earth systems. As defined by nationwide consensus among scientists and educators, this literacy has two key parts. First, a literate person is defined, in language that echoes the above definition of scientific literacy. Second, a set of concepts are listed, organized into six to nine big ideas or essential principles. This defining process was undertaken first for ocean literacy, then for the Great Lakes, estuaries, the atmosphere, and climate.