Influence Of Biomass Emissions Upon Habitability, Biosignatures and Detectability In Earth-like Atmospheres Source: astro-ph.EP O2 (left) and O3 (right) vmr profiles of various Earth-like scenarios orbiting in the HZ around the star AD Leo compared with the modern Earth around the Sun shown in grey. The other scenarios are grouped into 3 "families": "modern" Earth with Earth's biomass around AD Leo (solid black line, overlapped by grey line for O2); an Earth with Earth's biomass and reduced O2 concentrations (solid blue line) along with increased (100 PAL) CO2 concentrations (shortdashed blue line), increased (100% sRH, ‘wet’) surface relative humidity (longdashed blue line) and lowered (0.1% sRH, ‘dry’) surface relative humidity (dashdotted blue line); an abiotic "dead" Earth with removed biomass (solid yellow line) along with increased CO2 concentrations (short-dashed yellow line), increased surface relative humidity (long-dashed yellow line) and lowered surface relative humidity (dash-dotted yellow line).