As an aside:
This particular paper doesn't say anything about how the resulting chaotic eccentricity manifests itself in temperature models of the past. It leaves this up to the paleoclimatologists.
In a separate paper by the same author
(here) however, they say:
Quote:
The large size of these variations makes it then understandable that a signature of these variations could be recorded in the sedimentary paleoclimate signal. Indeed, although the global mean annual insolation on earth varies as e^2 and thus is not much influenced by eccentricity variations, this is not the case for seasonal variations. Indeed, if one considers a black body with uniform temperature at distance d of a star, using Stefan’s law for the emission of a black body, one finds that its surface temperature T is proportional to d^−1/2. In this case, the difference δT be-tween perihelion and aphelion temperature will be given by
δT/T≈(1/2).(2ae/a)=e.
A change of 0.02 in the eccentricity corresponds thus in this simplified model, to a change of about 0.02 × 300 = 6K in the difference between perihelion and aphelion temperatures.
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(The last statement being a handy rule of thumb).
They have made all this available on their website
here.
Need to be cautious about how to interpret this information however .. which is why they refer it all to the paleoclimatologists.
Cheers
PS: The resulting eccentricity seems to manifest itself over ~2.4Myr cycle.