Complex sentence: In post-season analysis Hurricane Irene was strengthened slightly with the minimum pressure reduced slightly and the Accumulated Cyclone Energy was marginally increased to 13.14 × 10 4 kt 2.
Split into simpler sentences: In post-season analysis, Hurricane Irene's peak was raised slightly with the minimum pressure reduced slightly. As such, the Accumulated Cyclone Energy was marginally increased to 13.14 × 10 4 kt 2.