How Was Early Earth Kept Warm?

Hydrogen-Nitrogen Greenhouse Warming in Earth's Early Atmosphere

(2013) R. Wordsworth et al.   SCIENCE

HYDROGEN GREENHOUSE PLANETS BEYOND THE HABITABLE ZONE

(2011) Raymond Pierrehumbert et al.   Astrophysical Journal Letters

Mineralogical constraints on Precambrian pCO2

(2011) Christopher T. Reinhard et al.   NATURE

Neoarchean paleoweathering of tonalite and metabasalt: Implications for reconstructions of 2.69Ga early terrestrial ecosystems and paleoatmospheric chemistry

(2011) Steven G. Driese et al.   PRECAMBRIAN RESEARCH

No climate paradox under the faint early Sun

(2010) Minik T. Rosing et al.   NATURE

Nitrogen-enhanced greenhouse warming on early Earth

(2009) Colin Goldblatt et al.   Nature Geoscience

A Revised, Hazy Methane Greenhouse for the Archean Earth

(2008) Jacob D. Haqq-Misra et al.   ASTROBIOLOGY