Jurai tricks Mirei into taking his powers, which leads to her hand being set on fire, and to put it out, she summons a sphere of water and freezes it, which just causes it to evaporate. Mieri is 15 years old at the start of the series, and the average height of a 15 year old Japanese girl is 156cm (or 1.56m).
1 pixel = 1.56m/1421 = 0.00109781844m
0.00109781844m X 223 = 0.244813512m
1 pixel = 0.244813512m/350 = 0.000699467177m
0.000699467177m X 904 = 0.632318328m
0.632318328m/2 = 0.316159164m
Volume as a sphere (obviously) and weight as water (obviously).
V = 4/3πr^3
= 4/3 X π X 0.316159164^3
= 0.132374988
Weight of water is 1000kg per m^3.
M = 0.132374988 X 1000kg
= 132.374988kg
Specific heat of water is 4182 joules per kg. The average temperature of air is 22.4 degrees Celsius (they're in a desert wasteland, but don't appear to be too hot).
E = 132.374988 X 4182 X 22.4
= 12400465.3 joules
= 0.002963782337476 tons of TNT (2.963782337476kg of TNT)
Next to melt the ice. It takes 333.55 kilojoules to melt 1kg of ice.
E = 333.55 X 132.374988
= 44153.6772 kilojoules
= 0.01055298212237 tons of TNT (10.55298212237kg of TNT)
Final Results
Mirei freezes sphere of ice = 2.964kg of TNT
Dark and Dark of the End melts Mirei's ice = 10.553kg of TNT
