  Most of the exoplanets detected up to now transit in front of their host
stars, allowing for the generation of transmission spectra; the study of
exoplanet atmospheres relies heavily upon accurate analysis of these spectra.
Recent discoveries mean that the study of atmospheric signals from low-mass,
temperate worlds are becoming increasingly common. The observed transit depth
in these planets is small and more difficult to analyze. Analysis of simulated
transmission spectra for two small, temperate planets (GJ 1214 b and K2-18 b)
is presented, giving evidence for significant differences in simulated transit
depth when the water vapor continuum is accounted for when compared to models
omitting it. These models use cross-sections from the CAVIAR lab experiment for
the water self-continuum up to 10,000 cm$^{-1}$; these cross-sections exhibit
an inverse relationship with temperature, hence lower-temperature atmospheres
are the most significantly impacted. Including the water continuum strongly
affects transit depths, increasing values by up to 80 ppm, with the differences
for both planets being detectable with the future space missions Ariel and
JWST. It is imperative that models of exoplanet spectra move toward adaptive
cross-sections, increasingly optimized for H$_2$O-rich atmospheres. This
necessitates including absorption contribution from the water vapor continuum
into atmospheric simulations.
