What was done
Seasonal summer monsoon (June-September) rainfall data from 120 east Asia stations were examined for the period 1881-1998.

What was learned
A series of statistical tests revealed the presence of short-term variability in rainfall amounts on decadal and longer time scales, the longer "epochs" of which were found to last for about three decades over India and China and approximately five decades over Japan.  In spite of year-to-year fluctuations and the decadal variability in the rainfall records, no significant long-term trends were observed in the data.

What it means
The observational history of summer rainfall trends in east Asia does not support climate alarmist claims of intensified monsoonal conditions in this region as a result of CO2-induced global warming.  As for the decadal variability inherent in the record, it "appears to be just a part of natural climate variations."