flood water calculation | Python Fiddle

# In which I calculate the volume of water it would be required to cover the entire planet, including Mt. Everest, and how
# many times it is the amount of water present on Earth.
# Sources -
# http://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html
# http://ga.water.usgs.gov/edu/2010/gallery/global-water-volume.html
# http://en.wikipedia.org/wiki/Mount_Everest

from math import pi

radius_earth = 6371.0                # Volumetric mean radius in kilometers
volume_water = 10633450.0            # In cubic kilometer
volume_earth = 108.321*(10**10)      # In cubic kilometer
height_everest = 8.848               # In kilometers

volume_everest_sphere = 4*pi*((radius_earth+height_everest)**3)/3.0
volume_difference = volume_everest_sphere-volume_earth
times_water = volume_difference/volume_water

print volume_difference, times_water

# But, there is the small matter of all the hills and mountains on the planet and the volume they'd take up.
# So, doing some hand waving and back of the hand calculations I guesstimate that if we take the height of Mt. Everest as 8 kms
# instead of 8.8 kms, it should more than account for the volume taken up by all the hills and mountains on Earth.

revised_volume = 4*pi*((radius_earth+height_everest-0.848)**3)/3.0
revised_volume_difference = revised_volume-volume_earth
revised_times_water = revised_volume_difference/volume_water

print revised_volume_difference, revised_times_water

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