Summary: Online at www.sciencemag.org/cgi/content/full/295/
7. J. P. Peixoto, A. H. Oort, Physics of Climate (American
Institute of Physics, New York, 1992).
8. Anomalies are defined as the deviation from the
mean annual cycle for the years 19851993.
9. The commonly used NINO3 ENSO index is defined as
the 150°W90°W 5°S5°N average sea surface tem-
10. M. Chelliah, P. Arkin, J. Clim. 5, 371 (1992).
11. The two-dimensional JFD is a matrix whose ele-
ments contain the frequency of occurrence of var-
ious pairs of parameter values (in this case, SW and
LW fluxes). In this research, all data sets are
monthly means and are mapped to 5° 5° spatial
resolution. The JFDs are calculated on the basis of
these data sets.
12. The mean annual cycle is calculated from the
composite 19851993 JFD, and then the JFD
anomalies time series is derived. The JFD anomalies