HIGHLIGHT: The seasonal mean NINO3.4 anomaly was -0.1 C for AMJ2012, down from MAM (-0.4).
The CA method, acting on global AMJ2012 seasonal means as latest input, but using a string of global SST going back one year, has nine out of twelve of its members in neutral territory from now until further notice. Three members go for a weak to moderate El Nino (>+0.5) late in 2012. All members fall back in weak to moderate negative territory in 2013.
Weights have changed only modestly from last month, as it should when the system behaves properly according to its own forecast. Year 2000 carries a +0.18 weight, which is high in the business of a constructed analogue (a natural analogue would have weight 1.00; all other years 0.). This high weight has popped up late last year as a high weight assigned to 1999 (and moving forward in the Table with same speed as real time); in principle this can last as long as the prediction time scale (no more than 2 years). 1996 is high –ve since just a few months.
There are five (somewhat recent) years with high +ve weight!, and four (somewhat older) years with high -ve weight. OCN flavor is much reduced compared to a few years ago (2010 has –ve weight), but not completely gone.
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 MJJ2011 thru AMJ2012). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2011 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2011). Data currently thru June 2012.
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP
|
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Weigt |
1956 |
xx |
-4 |
1966 |
xx |
-14 |
1976 |
xx |
10 |
1986 |
xx |
-9 |
1996 |
xx |
-16 |
2006 |
xx |
5 |
1957 |
xx |
7 |
1967 |
xx |
1 |
1977 |
xx |
10 |
1987 |
xx |
-10 |
1997 |
xx |
6 |
2007 |
xx |
7 |
1958 |
xx |
0 |
1968 |
xx |
-5 |
1978 |
xx |
6 |
1988 |
xx |
-5 |
1998 |
xx |
-1 |
2008 |
xx |
6 |
1959 |
xx |
-2 |
1969 |
xx |
-7 |
1979 |
xx |
-1 |
1989 |
xx |
-1 |
1999 |
xx |
-3 |
2009 |
xx |
13 |
1960 |
xx |
1 |
1970 |
xx |
1 |
1980 |
xx |
3 |
1990 |
xx |
-4 |
2000 |
xx |
18 |
2010 |
xx |
-2 |
1961 |
xx |
-3 |
1971 |
xx |
-6 |
1981 |
xx |
1 |
1991 |
xx |
0 |
2001 |
xx |
7 |
2011 |
xx |
9 |
1962 |
xx |
3 |
1972 |
xx |
4 |
1982 |
xx |
-5 |
1992 |
xx |
1 |
2002 |
xx |
9 |
2012 |
xx |
NA |
1963 |
xx |
6 |
1973 |
xx |
-5 |
1983 |
xx
|
4 |
1993 |
xx |
-4 |
2003 |
xx |
-1 |
xx |
Xx |
|
1964 |
xx |
1 |
1974 |
xx |
-3 |
1984 |
xx |
11 |
1994 |
xx |
-4 |
2004 |
xx |
-5 |
xx |
Xx |
|
1965 |
xx |
2 |
1975 |
xx |
1 |
1985 |
xx |
-11 |
1995 |
xx |
-3 |
2005 |
xx |
-1 |
xx |
Xx |
Weights are high +ve (>+0.10) for 2009,2000,1984,1977,1976
Weights are high -ve (< - 0.10) for 1996,1987,1985,1966
Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):
-0.08 |
0 |
0.14 |
0.28 |
0.31 |
0.38 |
0.42 |
0.44 |
0.35 |
0.27 |
0.07 |
-0.1 |
-0.28 |
-0.45 |
-0.53 |
-0.61 |
-0.68 |
-0.68 |
-0.67 |
-0.63 |
-0.61 |
MJJ |
JAS |
SON12 |
NDJ |
JFM13 |
MAM |
MJJ13 |
JAS |
SON |
NDJ |
One month ago:
-0.39 |
-0.29 |
-0.06 |
0.16 |
0.19 |
0.21 |
0.28 |
0.32 |
0.33 |
0.25 |
0.21 |
0.08 |
-0.05 |
-0.26 |
-0.33 |
-0.38 |
-0.42 |
-0.47 |
-0.48 |
-0.47 |
-0.44 |
MAM |
MJJ |
JAS2012 |
SON |
NDJ |
JFM |
MAM |
MJJ |
JAS |
SON2013 |
NDJ |
Two months ago:
-0.61 |
-0.51 |
-0.28 |
0.03 |
0.06 |
0.05 |
0 |
-0.01 |
-0.01 |
-0.01 |
-0.06 |
-0.02 |
-0.05 |
-0.07 |
-0.19 |
-0.19 |
-0.18 |
-0.18 |
-0.18 |
-0.17 |
-0.1 |
MAM2012 |
MJJ |
JAS |
SON |
NDJ |
JFM2013 |
MAM |
MJJ |
JAS |
SON |
Three months ago
-0.82 |
-0.72 |
-0.49 |
-0.14 |
-0.02 |
0.01 |
-0.03 |
-0.1 |
-0.16 |
-0.19 |
-0.15 |
-0.11 |
-0.01 |
0.02 |
0.01 |
-0.05 |
-0.04 |
-0.01 |
-0.02 |
-0.02 |
-0.01 |
JFM12 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM13 |
MAM |
MJJ |
JAS |
SON |
Four months ago:
-0.99 |
-0.93 |
-0.73 |
-0.36 |
-0.12 |
0.06 |
0.15 |
0.15 |
0.12 |
0.1 |
0.09 |
0.14 |
0.17 |
0.24 |
0.16 |
0.08 |
-0.01 |
0.01 |
0.01 |
0.01 |
0 |
JFM12 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM13 |
MAM |
MJJ |
JAS |
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JFM13 |
MAM |
MJJ |
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Anomalies relative to 1981-2010 climo, as of the May 2011 release. Older forecasts
(previous to May 2011 release) are relative to 71-2000