(a) The ‘Green House’ effect is the process by which radiation from a planet’s atmosphere warms the planet’s surface to a temperature above what it would be without its atmosphere. If a planet’s atmosphere contains radioactively active gases (i.e., greenhouse gases) they will radiate energy in all directions. Part of this radiation is directed towards the surface,warming it. The intensity of the downward radiation that is, the strength of the Green House effects will depend on the atmosphere’s temperature and on the amount of greenhouse gases that the atmosphere contains.