The time in アルス is normally 9, 10 または 11 時間 ahead of the time in ニューヨーク, but because these time zones don't share the same start and end times for daylight saving time, the time in アルス can for a short while be 10 時間 ahead of the time in ニューヨーク.
アルス does not change between summer time and winter time.