  The habitability of planets in binary star systems depends not only on the
radiation environment created by the two stars, but also on the perturbations
to planetary orbits and rotation produced by the gravitational field of the
binary and neighbouring planets. Habitable planets in binaries may therefore
experience significant perturbations in orbit and spin. The direct effects of
orbital resonances and secular evolution on the climate of binary planets
remain largely unconsidered.
  We present latitudinal energy balance modelling of exoplanet climates with
direct coupling to an N Body integrator and an obliquity evolution model. This
allows us to simultaneously investigate the thermal and dynamical evolution of
planets orbiting binary stars, and discover gravito-climatic oscillations on
dynamical and secular timescales.
  We investigate the Kepler-47 and Alpha Centauri systems as archetypes of P
and S type binary systems respectively. In the first case, Earthlike planets
would experience rapid Milankovitch cycles (of order 1000 years) in
eccentricity, obliquity and precession, inducing temperature oscillations of
similar periods (modulated by other planets in the system). These secular
temperature variations have amplitudes similar to those induced on the much
shorter timescale of the binary period.
  In the Alpha Centauri system, the influence of the secondary produces
eccentricity variations on 15,000 year timescales. This produces climate
oscillations of similar strength to the variation on the orbital timescale of
the binary. Phase drifts between eccentricity and obliquity oscillations
creates further cycles that are of order 100,000 years in duration, which are
further modulated by neighbouring planets.

Earth and Planetary Astrophysics