To determine the amount of water in the air in the form of water vapor and water droplets in clouds at any given time, we need to understand the scale and typical amounts involved in the Earth's atmosphere.
When considering the options provided:
a) 13,000 km³
b) 1,580 km³
c) 117,000 km³
d) 1,000,000 km³
The correct value for the amount of water present in the atmosphere can be determined as follows:
1. Remember that we are focusing on the total combined amount of both water vapor and droplets within clouds.
2. We compare the given values considering typical scientific knowledge about Earth's water cycle, where the total amount of atmospheric moisture is significantly impactful but not overly exaggerated.
By assessing the potential volumes and common meteorological data:
- Option (a) 13,000 km³ is a reasonable and scientifically supported estimate for the water vapor and droplets present in the air.
- Option (b) 1,580 km³ is considerably too low for the total atmospheric water content.
- Option (c) 117,000 km³ is overly high and not commonly supported by established data.
- Option (d) 1,000,000 km³ is vastly exaggerated and not reflective of reality.
Thus, the correct choice, which aligns with empirical data and scientific consensus, is:
a) 13,000 km³
