arxiv.org...
If you read page 11 from the recent paper (June 5) by the originator of the study even the author expresses reservations as to how quickly using Earth's signature as a model will yield results. He qualifies that the instrumentation needed is in the conceptual phase, but remains hopeful.
ET’s Conclusions
In conclusion, if an extraterrestrial (or extrasolar) observer was looking at the
Earth from an astronomical distance, and similarly if we were observing an Earthlike
exoplanet, we would be able to determine some of its properties. From al these
properties, those regarding the possibility of finding life would be:
• Habitability signatures:
Atmospheric composition
Variability and albedo
Spectral shape (Rayleigh scattering, atmospheric properties)
Rotational period
Presence of oceans (glint)
Presence of dynamic weather ... and possibility of liquid water
• Life signatures:
Atmospheric disequilibrium caused by life
• Complex life (plant/animal) signatures:
Presence of complex life (red or other edges)
Fluorescence
Presence of biomass from circular polarization
(more)
