It has been investigated that in Hongfeng Lake and Baihua Lake, there are 139 kinds or subkinds of birds, belonging to 40 families or sub-families of the 17 catalogues of the class of birds. They make up 28.8 percent of the 482 kinds or sub-kinds of birds recorded in Guizhou Province. There-fore it is clear that these two lakes are the regions in the province where lots of birds dwell.
Adjustment factors were calculated for all of the combinations using a modern record maintained at the Churchill airport.
The historical fluctuations are meshed with the modern record to provide a picture of the lakes' fluctuations until the late twentieth century.
The regional aggregation allows the voluminous fragmentary information available in historical sources to be used systematically to produce multi-year time series that can be directly integrated into the modern record for each region.
These results suggest that droughts of greater magnitude and duration than those observed in the modern record have occurred in the recent geological past.
First a cluster analysis was used to separate typhoons in the modern record into 3 categories based on track type.