Water vapor, which contributes between 41% and 67% of the Earth's greenhouse effect, has been part of the atmosphere since Earth first formed. Liquid water - cl

Water vapor, which contributes between 41% and 67% of the Earth's greenhouse effect, has been part of the atmosphere since Earth first formed. Liquid water - clouds - contributes between 25% and 31%, and has likewise been part of the atmosphere since before the existence of humans. In other words, the effect of atmospheric water has had billions of years to reach equilibrium. Atmospheric water, at a global scale, is also not significantly affected by human activity. The remainder of the greenhouse effect is caused by gases like CO2 and methane, which are affected by human activity. They contribute significantly - CO2 is a mere 0.04% of the atmosphere but is responsible for between 18% and 26% of the Earth's greenhouse effect, methane 6% - and we have significantly altered the concentration of these gases since the Industrial Revolution. The amount of CO2 has nearly doubled, and the amount of methane has more than doubled. So no, this mission is not a waste of time.