We present values of mean monochromatic extinction coefficients for wavelengths between 360 and 953 nm for Terskol Peak (the Northern Caucausus). The values are derived from CCD photometric observations taken from August 1996 to August 2002 with the Two-Channel Focal Reducer of the Max-Planck Institute for Aeronomy which is attached to the 2-m RCC telescope at the observatory on Terskol Peak. The values obtained, together with ones published before, were used for the investigation of time variations of the aerosol component of atmospheric extinction. For the period under investigation (from 1973 to 2002), no systematic long-standing changes of atmospheric transparency are found. Season variations of aerosol extinction are revealed; the most value of the aerosol extinction is observed in spring. It is shown from the study of the wavelength dependence of the extinction coefficients that the aerosol scattering can be fitted by λ^-α where the parameter α equals 0.9,1.2 and 2.2 for observations made in spring, in summer, and in autumn, respectively. The mean value α = 1.4 is indicative of a good atmospheric transparency at the Terskol Peak Observatory.