The
canonical correlation analysis (CCA) forecast of SST in the central Pacific
(Barnett et al. 1988, Science, 241, 192‑196; Barnston and
Ropelewski 1992, J. Climate, 5, 1316‑1345), is shown in Figs.
F1 and F2. This forecast
is produced routinely by the Prediction Branch of the
Climate
Prediction
Center
. The predictions from the National Centers for
Environmental Prediction (NCEP) Coupled Forecast System Model (CFS03) are
presented in Figs. F3 and F4a,
F4b. Predictions
from the Markov model (Xue, et al. 2000: J. Climate, 13,
849‑871) are shown in Figs. F5 and F6.
Predictions from the latest version of the LDEO model (Chen et al.
2000: Geophys. Res. Let., 27, 2585‑2587) are shown in Figs.
F7 and F8.
Predictions using linear inverse modeling (Penland and Magorian 1993:
J. Climate, 6, 1067‑1076) are shown in Figs. F9
and F10. Predictions from the Scripps / Max
Planck Institute (MPI) hybrid coupled model (Barnett et al. 1993: J.
Climate, 6, 1545‑1566) are shown in Fig. F11.
Predictions from the ENSO‑CLIPER statistical model (Knaff and
Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in
Fig. F12.
Niņo 3.4 predictions are summarized in Fig. F13,
provided by the Forecasting and Prediction Research Group of the IRI.
The CPC and
the contributors to the Forecast Forum caution potential users of this
predictive information that they can expect only modest skill.
Outlook
ENSO-neutral conditions
are expected during the next 3-6 months.
Discussion
During September, equatorial SST anomalies
greater than +0.5°C were found between 160°E and 170°E, while negative
anomalies less than -0.5°C were observed
at most locations between 130°W and the South American coast (Figs T9 and T18).
The
SST departures in the Niņo 3 and Niņo
1+2 regions were negative, while weak positive departures were observed
in the Niņo 4
region (Table T2 and
Fig. T5). During
the last three months surface and subsurface temperature anomalies have
decreased, especially in the eastern equatorial Pacific (Figs. T9,
T15 and T17), while
atmospheric conditions (low-level winds, convection and sea level pressure)
remained near average over most of the tropical Pacific (Figs.
T7, T8, and T25).
The large spread of the most recent statistical and coupled
model forecasts (Figs. F1,
F2, F3, F4a,
F4b, F5, F6,
F7, F8, F9,
F10, F11, F12
and F13)
from weak La Niņa to weak El Niņo indicates
considerable uncertainty. However,
current conditions and recent observed trends support a continuation of ENSO-neutral
conditions for the next 3-6 months.
Weekly
updates of SST, 850-hPa wind, OLR and features of the equatorial subsurface
thermal structure are available on the
Climate
Prediction
Center homepage at:
http://www.cpc.ncep.noaa.gov/
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