So as stated on the chapter, the power of Deku's final punch caused winds so strong that they could reach all the way to America even days after the event.
The shortest distance between Japan and Washington, where the reporter is located, is
10,906 kilometers, that will be our radius.
The bulk of the atmosphere is located close to Earth’s surface—up to a distance of around 8 to 15 kilometers, so we will be using
11.5 kilometers for our height.
Having these two values, we can use
this calculator to find the mass of air Deku's punch had to push to reach all they way to America. The average elevation of Japan is 438 meters above sea level, the air pushed has a thickness of at least 11,500 meters, and an area of 373663656589428.40 square meters (pi*10906000^2).
Mass =
2.92*10^18 Kilograms of Air
Now we just need to find the speed of the winds, which were stated to be "strong". The wind reached America a few days after the battle, let's say 2 days, or 172800 seconds:
Speed = 9723620/172800 =
56.27 m/s
Strong stuff indeed, probably too strong, but let's continue.
Finally we can the kinetic energy of this feat.
Energy = 1/12*2920000000000000000*56.27^2 =
770469472333333333333.33 Joules
Giving us a grand total of...
184.14 Gigatons.