Abstract: Based on the collected and sorted records of the drought and flood in the middle and lower reaches of the Yellow River region,China from 1470 to 1911,the paper reconstructed the sequence of drought and flood of 36 stations and the history map of the study area,and analyzed the spatial characteristics using EOF and REOF.The results from the EOF analysis showed that the cumulative variance contribution rate of the first 4 models is 71.85%.The main characteristics indicated that the first,the second and the fourth models displayed a longitude distribution,while the third model was shown a latitude distribution.The spatial distribution of the first eigenvector field were all positive,which indicated that there was consistency for the changes of drought and flood in the middle and lower reaches of the Yellow River region.But there were obvious difference among the rest of the eigenvector fields,which illustrated the drought and flood change also had the local features under the different background conditions and field effects.Based on the results from the REOF analysis,there can be divided into five typical sensitive climate partitions in the middle and lower reaches of the Yellow River region.The analysis laid the foundation for the further study about drought/flood regional characteristics.

Key words: EOF, REOF, drought and flood, spatial characteristics, middle and lower reaches of the Yellow River