Upon defeating Alduin in Sovngarde, he creates a massive storm in his death throes. Note also in the background one of the statues in Sovngarde are destroyed. First up, let me point out Alduin's last words...
Alduin (Skyrim)
Which is very different from the words of storm call, Strun Bah Qo. Alduin doesn't even say any of those words. My point being this is not a specific shout but Alduin's power getting unleashed upon his death. The horizon from 1.7m (average height) up is 4.7km away, or 4700m. Storm clouds are cumulonimbus, which are on average 12000m tall. Volume of the area as a cylinder.Skyrim said:
V = πr^2h
= π X 4700^2 X 12000
= 8.32773381e11m^3
Density of a cloud/air is 1.003kg/m^3.
M = 8.32773381e11 X 1.003
= 835271701143kg
Finally for our timeframe.
T = 4700m/3.17s
= 1482.64984m/s
Finally for the energy.
KE = (0.5)mv^2
= (0.5) X 835271701143 X 1482.64984^2
= 9.18068237e17 joules
= 219.42357480879542209 megatons
Final Results
Alduin's death throes = 219.424 megatons
