HIGHLIGHT:� The seasonal mean NINO3.4 anomaly was about -0.13 C for NDJ2013/14, a continued slightly �ve value.�
The CA method, acting on global NDJ2013 seasonal means as latest input, but using a string of global SST going back one year, has all of its members staying negative in the neutral zone for Nino34 thru FMA2014.� By late spring 2014 a majority of members is neutral, but now on the positive side, and a few grow >+0.5, even >+1.0 later in 2014. But two members stay slightly �ve for all of 2014!
Weights have changed from last month, with some increase in weights. 1987 (thru December 2012 that particular past situation was labeled 1986, and next month it will be 1988) has now been holding on to a large negative weight for nearly two years: since spring 2012. �In fact it increased to negative 0.18.
OCN flavor is weaker. The last 13 years have generally +ve weight, but 2010 and 2006 suddenly went negative. 1980-1999 is mainly negative except for a few years that are positive.
Early warning: Weights will change next month (data thru February 2014) for three reasons. First, weights are labelled by the year of the middle month of the latest 3 mo period. So when changing NDJ to DJF, we see, for instance, December 1987 turn to January 1988, so weights (even if unchanged) move forward by one year in the table below.� Secondly, one year of data will be added, so the larger co-variance matrix will possibly respond differently to the co-linearity present. Lastly, there will be normal changes one sees every month relative to the previous 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 DJF2013 thru NDJ2013/14). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2012 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2012). Data currently thru Jan 2014.
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP
|
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Weigt |
1956 |
xx |
�5 |
1966 |
xx |
-1 |
1976 |
Xx |
-4 |
1986 |
xx |
-3 |
1996 |
xx |
�2 |
2006 |
xx |
-2 |
1957 |
xx |
�9 |
1967 |
xx |
�3 |
1977 |
Xx |
�0 |
1987 |
xx |
-18 |
1997 |
xx |
-6 |
2007 |
xx |
�5 |
1958 |
xx |
�8 |
1968 |
xx |
-6 |
1978 |
Xx |
�7 |
1988 |
xx |
�0 |
1998 |
xx |
�0 |
2008 |
xx |
11 |
1959 |
xx |
�0 |
1969 |
xx |
�2 |
1979 |
Xx |
10 |
1989 |
xx |
�7 |
1999 |
xx |
-10 |
2009 |
xx |
�7 |
1960 |
xx |
-6 |
1970 |
xx |
�1 |
1980 |
Xx |
-6 |
1990 |
xx |
12 |
2000 |
xx |
�3 |
2010 |
xx |
-8 |
1961 |
xx |
�6 |
1971 |
xx |
-2 |
1981 |
Xx |
-9 |
1991 |
xx |
-9 |
2001 |
xx |
�8 |
2011 |
xx |
12 |
1962 |
xx |
�0 |
1972 |
xx |
14 |
1982 |
Xx |
-4 |
1992 |
xx |
-11 |
2002 |
xx |
�8 |
2012 |
xx |
�9 |
1963 |
xx |
-4 |
1973 |
xx |
�0 |
1983 |
xx
|
-6 |
1993 |
xx |
-9 |
2003 |
xx |
�2 |
2013 |
xx |
NA |
1964 |
xx |
�-3 |
1974 |
xx |
-2 |
1984 |
Xx |
�5 |
1994 |
xx |
�2 |
2004 |
xx |
�4 |
xx |
Xx |
|
1965 |
xx |
-6 |
1975 |
xx |
-5 |
1985 |
Xx |
�3 |
1995 |
xx |
�6 |
2005 |
xx |
�9 |
xx |
Xx |
Weights are high +ve (>+0.10) for 2011, 2008,1990, 1979, 1972
Weights are high -ve (< - 0.10) for 1999,1992,1987
Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):
-0.13 |
-0.17 |
-0.21 |
-0.24 |
-0.16 |
0.01 |
0.17 |
0.32 |
0.29 |
0.34 |
0.43 |
0.6 |
0.61 |
0.54 |
0.43 |
0.39 |
0.35 |
0.3 |
0.25 |
0.26 |
0.28 |
NDJ |
JFM14 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM15 |
MAM |
MJJ |
JAS |
One month ago:
-0.13 |
-0.11 |
-0.12 |
-0.13 |
-0.12 |
-0.04 |
0.13 |
0.27 |
0.37 |
0.3 |
0.3 |
0.35 |
0.46 |
0.42 |
0.32 |
0.25 |
0.22 |
0.22 |
0.17 |
0.1 |
0.05 |
NDJ |
JFM14 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM15 |
MAM |
MJJ |
Two months ago
-0.14 |
-0.14 |
-0.12 |
-0.17 |
-0.19 |
-0.16 |
-0.04 |
0.14 |
0.27 |
0.32 |
0.25 |
0.22 |
0.27 |
0.38 |
0.36 |
0.26 |
0.18 |
0.17 |
0.19 |
0.18 |
0.11 |
SON13 |
NDJ |
JFM14 |
MAM |
MJJ |
JAS |
SON14 |
NDJ |
JFM15 |
MAM |
MJJ |
Three months ago
-0.23 |
-0.25 |
-0.26 |
-0.27 |
-0.32 |
-0.31 |
-0.25 |
-0.09 |
0.15 |
0.34 |
0.4 |
0.32 |
0.3 |
0.42 |
0.61 |
0.65 |
0.55 |
0.41 |
0.36 |
0.34 |
0.25 |
SON13 |
NDJ |
JFM14 |
MAM |
MJJ |
JAS |
SON14 |
NDJ |
JFM15 |
MAM |
Four months ago
-0.21 |
-0.26 |
-0.28 |
-0.26 |
-0.23 |
-0.27 |
-0.28 |
-0.24 |
-0.1 |
0.17 |
0.36 |
0.44 |
0.33 |
0.33 |
0.47 |
0.73 |
0.81 |
0.73 |
0.59 |
0.53 |
0.48 |
JAS |
SON13 |
NDJ |
JFM14 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM15 |
MAM |
Anomalies relative to
1981-2010 climo.