24
(c) 2000
D.B.Stephenson@reading.ac.uk
0 20
40 60 80
a) Autocorrelation
Function
Lag
1.0
0.8
0.6
0.4
0.2
0.0
Persistence in daily NAO …
Autocorrelations persist up until
very long lags
=> early warning system may be possible (few week's lead).
b) Decorrelation
Time vs Maximum Lag
Lag in days
50
40
30
20
10
0
0 200
600 1000