A CHARACTERISTIC TIME-SCALE IN THE GLOBAL TEMPERATURE RECORD

Using modern time series analysis we discover a characteristic time sc ale in the global temperature record. This time scale corresponds to a bout 20 months and separates processes that promote a trend in the pas t from processes that reverse this tendency. This characteristic scale has important implications one of which might be that the El Nino/La Nina cycle may act as a mechanism countering the tendency of shorter t ime scale events to organize a positive or a negative temperature tren d.