Oceanography is the sum of these several branches. Oceanographic research entails the sampling of seawater and marine life for close study, the remote sensing of oceanic processes with aircraft and Earth-orbiting satellites, and the exploration of the seafloor by means of deep-sea drilling and seismic profiling of the terrestrial crust below the ocean bottom. Greater knowledge of the world’s oceans enables scientists to more accurately predict, for example, long-term weather and climatic changes and also leads to more efficient exploitation of the Earth’s resources. Oceanography also is vital to understanding the effect of pollutants on ocean waters and to the preservation of the quality of the oceans’ waters in the face of increasing human demands made on them. Oceanography has been transformed through the use of fluorescence to assay biology. Light-absorbing pigments cause many organisms to naturally fluoresce. Primarily, but not exclusively, these pigments are associated with photosynthesizing organisms, such as algae, aquatic vascular plants, and aerobic anoxygenic photosynthetic (AAP) bacteria.