HIGHLIGHT: The seasonal mean NINO3.4 anomaly was +1.54 for DJF2009, a decrease from NDJ.
The CA method, acting on global DJF2010 seasonal means as latest input forecasts the 3 mo running mean anomaly for Nino34 to stay in El Nino territory thru FMA, with most members well in excess of +1.0C but none above 1.5C for three month means. In short a clear warm event followed by a cool-off later in 2010, with –ve Nino34 anomalies possible by summer, and 30% of the members in La Nina territory.
Large weight changes have taken place because the size of the covariance matrix increased by one. Also note that the weights, which should persist to make a good CA forecast, have shifted into the next year compared to last month.
Table 1. Inner products (IP; scaled such that the sum of absolute values is 100; not shown) and weights (Wgt multiplied by 100.) of each of the years to construct an analogue to the sequence of 12 consecutive overlapping 3-month periods defined as the base (currently the 12 overlapping seasons string JFM2009 thru DJ2010). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2009 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2009). Data currently thru Feb 2010.
|
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP
|
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Weigt |
|
1956 |
xx |
-2 |
1966 |
xx |
6 |
1976 |
xx |
-2 |
1986 |
xx |
0 |
1996 |
xx |
3 |
2006 |
xx |
1 |
|
1957 |
xx |
-13 |
1967 |
xx |
2 |
1977 |
xx |
3 |
1987 |
xx |
-2 |
1997 |
xx |
1 |
2007 |
xx |
13 |
|
1958 |
xx |
9 |
1968 |
xx |
0 |
1978 |
xx |
7 |
1988 |
xx |
4 |
1998 |
xx |
3 |
2008 |
xx |
6 |
|
1959 |
xx |
4 |
1969 |
xx |
12 |
1979 |
xx |
-4 |
1989 |
xx |
6 |
1999 |
xx |
-9 |
2009 |
xx |
1 |
|
1960 |
xx |
-9 |
1970 |
xx |
3 |
1980 |
xx |
-2 |
1990 |
xx |
6 |
2000 |
xx |
-7 |
2010 |
xx |
NA |
|
1961 |
xx |
-7 |
1971 |
xx |
5 |
1981 |
xx |
-3 |
1991 |
xx |
14 |
2001 |
xx |
0 |
xx |
xx |
|
|
1962 |
xx |
-2 |
1972 |
xx |
-7 |
1982 |
xx |
-7 |
1992 |
xx |
10 |
2002 |
xx |
13 |
xx |
xx |
|
|
1963 |
xx |
-3 |
1973 |
xx |
10 |
1983 |
xx
|
-4 |
1993 |
xx |
-3 |
2003 |
xx |
20 |
xx |
xx |
|
|
1964 |
xx |
2 |
1974 |
xx |
4 |
1984 |
xx |
-3 |
1994 |
xx |
-8 |
2004 |
xx |
8 |
xx |
xx |
|
|
1965 |
xx |
-13 |
1975 |
xx |
0 |
1985 |
xx |
-17 |
1995 |
xx |
3 |
2005 |
xx |
5 |
xx |
xx |
Weights are high +ve (>+0.10) for 2007,2003,2002,1992,1991,1973,1969. Weights are high -ve (< - 0.10) for 1985,1965,1957.
Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):
|
1.54 |
1.4 |
0.98 |
0.31 |
0.06 |
-0.04 |
-0.15 |
-0.28 |
-0.4 |
-0.43 |
-0.45 |
-0.47 |
-0.44 |
-0.36 |
-0.2 |
0 |
0.12 |
0.21 |
0.21 |
0.29 |
0.36 |
|
JFM10 |
MAM |
MJJ |
JAS |
SON10 |
NDJ |
JFM11 |
MAM |
MJJ |
JAS |
|||||||||||
|
One month ago: |
||||||||||||||||||||
|
1.67 |
1.59 |
1.26 |
0.68 |
0.34 |
0.15 |
0.09 |
-0.02 |
-0.15 |
-0.26 |
-0.25 |
-0.23 |
-0.21 |
-0.22 |
-0.19 |
-0.06 |
0.12 |
0.19 |
0.19 |
0.1 |
0.14 |
|
NDJ |
JFM10 |
MAM |
MJJ |
JAS |
SON10 |
NDJ |
JFM11 |
MAM |
MJJ |
JAS11 |
Two month ago:
|
1.45 |
1.44 |
1.29 |
0.91 |
0.58 |
0.32 |
0.17 |
0.14 |
0.07 |
-0.03 |
-0.1 |
-0.06 |
-0.03 |
-0.14 |
-0.2 |
-0.22 |
-0.1 |
0.06 |
0.1 |
0.07 |
-0.03 |
|
NDJ |
JFM10 |
MAM |
MJJ |
JAS |
SON10 |
NDJ |
JFM11 |
MAM |
MJJ11 |
Three months ago:
|
1.14 |
1.17 |
1.21 |
1.07 |
0.84 |
0.57 |
0.37 |
0.25 |
0.18 |
0.06 |
-0.04 |
-0.1 |
-0.06 |
-0.13 |
-0.19 |
-0.25 |
-0.26 |
-0.13 |
0.02 |
0.08 |
0.07 |
|
SON |
NDJ |
JFM10 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM11 |
MAM |
MJJ |
Anomalies relative to
1971-2000 climo.