On the Duration of Nonseasonal Temperature Oscillations

Abstract

The duration of nonseasonal sea and air temperature oscillations above and below arbitrarily fixed levels is investigated. There is close agreement between the observed mean durations and those expected from theory for a Gaussian random variable. Mean durations of sea temperature anomalies from long term monthly means above and below the 0C level vary between 3 and 5 months, those of air temperature between 2.5 and 3 months. There is almost no dependence upon latitude. The probability distributions are log-normal for durations not exceeding 2 or 3 times the mean duration. The largest observed durations above and below the 0C level are between 1 and 2 years while those above the +1.5C or below the −1.5C levels are between 1 and 2 months.