FIGURE F6. Time evolution of the NINO3.4 anomaly
forecasts up to 12 lead months by the NCEP/CPC Markov model (Xue et
al. 2000, J. Climate, 13, 849-871) initiated monthly up
to APR 2007. Anomalies were calculated relative to the 1971–2000
climatology . Shown in each panel are the forecasts grouped by three
consecutive starting months: (a) is for December, January, and
February, (b) is for March, April, and May, (c) is for June, July, and
August, and (d) is for September, October, and November. The observed
NINO3.4 SST anomalies are shown in the heavy-dashed lines.