Talk:2009 Pacific typhoon season/ACE calcs

This is the page for calculating the Accumulated Cyclone Energy for the 2009 Pacific typhoon season using data from the Japan Meteorological Agency.

The ACE is calculated by summing the squares of the estimated maximum sustained velocity of every active tropical storm (wind speed 35 knots or higher), at six-hour intervals. The numbers are usually divided by 10,000 to make them more manageable. The unit of ACE is 104 kt2, and for use as an index the unit is assumed. If any storms of a season happen to cross years, the storm's ACE counts for the previous year.


 * $$\sum_{}^{} \frac{{v_\mathrm{max}}^2}{10^4},$$

where vmax is estimated sustained wind speed in knots.