GC/GEOG 431/531 CLASS

ACTIVITY ON ENSO

Examples of correlations

Here is some information to supplement the printed handout. The numbers here are the same as those given in section C. Potential proxy records of ENSO, and the filtered data used in the correlation plots and scatter diagrams are the same as those illustrated in the bar charts headed Correlations: seasonal and annual SOI vs. filtered proxy records 1866-1988, although the maximum common period between each pair of series appears in the diagrams here. You can see larger versions of the scatterplots by selecting the small images shown here.

1.	Tree-ring index from drought-sensitive trees over a large region of the West centered on Arizona	r=-0.31 for December to February seasonal SOI
2.	As for 1, but for tree rings centered on Arkansas	r=0.17 for September to November seasonal SOI
3.	As for 1, but for tree rings centered on Texas	r=-0.57 for Annual SOI
4.	Temperature-sensitive oxygen isotope ratios in coral from the Galapagos islands	r=-0.26 for December to February SOI of prior year	r=0.37 for Annual SOI
5.	Teak tree rings in Java: small rings are formed when the dry season is long.	r=0.31 for June to August seasonal SOI
6.	The ratio of oxygen isotopes in ice on Quelccaya, Peru (> 6000m elevation). Thought to be a measure of the temperature at which the precipitation was formed.	r=-0.19 for September to November SOI of prior year
7.	Accumulation rate of snow on Quelccaya.	r=-0.12 for March to May seasonal SOI
8.	An index derived from historical documents recording El Niño events in coastal Peru and southern Ecuador.	r=0.52 for Annual SOI of prior year
9.	Winter precipitation at Santiago de Chile reconstructed from tree rings.	r=0.15 for December to February SOI of prior year	r=-0.26 for June to August seasonal SOI
10.	Summer temperature in Patagonia reconstructed from tree rings.	r=-0.26 for December to February seasonal SOI

Links to ENSO Sites

• NOAA's El Niño Theme Page (recommended starting place)
• Troup SOI data from Australia (The Long Paddock)
• Slightly dated e-mail message giving The Climate Analysis Center's Tahiti - Darwin SOI
• Lamont-Doherty's SOI page (leads to index archive & a graphical display utility).