  Much of the focus of exoplanet atmosphere analysis in the coming decade will
be atinfrared wavelengths, with the planned launches of the James Webb Space
Telescope (JWST) and the Wide-Field Infrared Survey Telescope (WFIRST).
However, without being placed in the context of broader wavelength coverage,
especially in the optical and ultraviolet, infrared observations produce an
incomplete picture of exoplanet atmospheres. Scattering information encoded in
blue optical and near-UV observations can help determine whether muted spectral
features observed in the infrared are due to a hazy/cloudy atmosphere, or a
clear atmosphere with a higher mean molecular weight. UV observations can
identify atmospheric escape and mass loss from exoplanet atmospheres, providing
a greater understanding of the atmospheric evolution of exoplanets, along with
composition information from above the cloud deck. In this white paper we focus
on the science case for exoplanet observations in the near-UV; an accompanying
white paper led by Eric Lopez will focus on the science case in the far-UV.
