A CCD camera and a laser measure the properties of these substances in the CLidar (KLYE-dar) technique. A quantity characterizing these substances is denoted by lowercase g and is calculated by an intensity-weighted integral over all azimuthal angles. NASA's MODIS instrument measures the asymmetry parameter and optical depth of these substances, which may be classified into an “accumulation mode” or a “coarse mode” based on size. In aggregate, the anthropogenic (*) “loading” of these substances has produced a net negative radiative forcing, in part since these substances directly scatter (10[1])sunlight and provide (-5[1])nuclei for (-5[1])cloud condensation. Volcanic eruptions produce “primary” examples of, for 10 points, what collections of atmospheric particulate matter, a type of colloid in which a solid is dispersed in a gas? (10[2])■END■