GEOLOGY

Detailed explanation-1: -The 75-page report, Atmospheric Implications of Increased Hydrogen Use, explains that H2 is an indirect greenhouse gas, which reacts with other greenhouse gases in the atmosphere to increase their global warming potential (GWP).

Detailed explanation-2: -Carbon monoxide is not a greenhouse gas. Methane, carbon dioxide, nitrogen dioxide, ozone and water vapour gases are the greenhouse gases.

Detailed explanation-3: -Methane, carbon dioxide, and nitrous oxide are greenhouse gasses because these trap more heat from the sunlight causing global warming. Oxygen is not a greenhouse gas.

Detailed explanation-4: -The main gases responsible for the greenhouse effect include carbon dioxide, methane, nitrous oxide, and water vapor (which are all natural compounds), and fluorinated gases (which are synthetic or man-made).