Page 90 - 2017地大报告电子书
P. 90

2017


                                                                  a lot of damage and hence changes in

                                                                  these events and their causes have been
                                                                  drawing considerable attention. This

                                                                  study investigated EPEs resulting from
                                                                  western North Pacific (WNP) tropical

                                                                  cyclones (TCs) and their potential link to El
                                                                  Nino-Southern-Oscillation (ENSO), using

                                                                  TC track data, daily precipitation data
                                                                  from  2313  stations  for  1951-2014,

               and the NCAR-NCEP reanalysis dataset. Two types of EPEs were considered: EPEs within
               500 km from the TC center, and those caused by mesoscale and synoptic systems, referred to as

               predecessor rain events (PREs), beyond 1000 km from the TC center. Results indicated significant
               impacts of TCs on EPEs along the coastal areas, and discernable effects in inland areas of China.

               However, the effect of TCs on EPEs tended to be modulated by ENSO. During neutral yea
               rs, inland areas of China are more affected by TC-induced extremeprecipitation than during

               El Nino or La Nina years, with the highest density of TC tracks and larger-than average
               numbers of tropical storms, typhoons, and landfalling TCs. During the El Nino phase, the central

               and eastern equatorial Pacific was characterized by higher sea surface temperature (SST), greater
               low-level vorticity (1000 hPa) and upper-level divergence (250 hPa), and stronger prevailing

               westerlies, which combined to trigger the movement of mean genesis to the eastern and
               southeastern WNP, resulting in fewer TCs passing through the Chinese territory.

                    论文链接:https://doi.org/10.1175/JCLI-D-17-0474.1

                    22.Timing of floods in southeastern China: Seasonal properties and potential causes
                    作  者 : Zhang Qiang*;Gu Xihui*; Singh Vijay P.; Shi Peijun ; Luo Ming
                     JOURNAL OF HYDROLOGY  卷 : 552   页 : 732-744   出版年 : SEP 2017

                    摘  要:Flood hazards and flood risks in southeastern China have been causing increasing
               concerns due to dense population and highly-developed economy. This study attempted to

               address changes
                    of seasonality, timing of peak floods and variability of occurrence date of peak floods using,

               circular statistical methods and the modified Mann-Kendall trend detection method. The causes
               of peak flood changes were also investigated. Results indicated that: (1) floods were subject to

               more seasonality and temporal clustering when compared to precipitation extremes. However,


               84
   85   86   87   88   89   90   91   92   93   94   95