CAJ | 학술논문

本文基于国家气象信息中心整编的全国1675个台站观测资料以及 NCEP／NCAR 的再分析资料，定义了候降水指数，利用旋转正交经验函数分解（REOF）法对全国候降水的季节进程进行了诊断分析，得到了表征气候态降水逐候进程的南、北方模态及各自的时间系数，发现 REOF 第二模态对应降水季节进程中的江南雨季。综合考虑我国南方（31°N 以南、110°E 以东区域）气候态降水的候进程、降水季节进程（4－6月降水指数减去6－8月降水指数）年际变率以及雨季（4－6月降水指数）降水年际变率的一致性，客观定义了江南雨季的地理范围。利用客观划定区域内的降水指数、925 hPa 经向风以及西北太平洋副热带高压500 hPa 脊线位置3个指标，制定了判定江南雨季起止时间的方法，进而对1961－2012年江南雨季起止时间进行了客观确定，给出了江南雨季起止时间序列。本文旨在为规范江南雨季的监测提供参考和借鉴，并为其预测提供科学基础。
본문기우국가기상신식중심정편적전국1675개태참관측자료이급 NCEP／NCAR 적재분석자료，정의료후강수지수，이용선전정교경험함수분해（REOF）법대전국후강수적계절진정진행료진단분석，득도료표정기후태강수축후진정적남、북방모태급각자적시간계수，발현 REOF 제이모태대응강수계절진정중적강남우계。종합고필아국남방（31°N 이남、110°E 이동구역）기후태강수적후진정、강수계절진정（4－6월강수지수감거6－8월강수지수）년제변솔이급우계（4－6월강수지수）강수년제변솔적일치성，객관정의료강남우계적지리범위。이용객관화정구역내적강수지수、925 hPa 경향풍이급서북태평양부열대고압500 hPa 척선위치3개지표，제정료판정강남우계기지시간적방법，진이대1961－2012년강남우계기지시간진행료객관학정，급출료강남우계기지시간서렬。본문지재위규범강남우계적감측제공삼고화차감，병위기예측제공과학기출。
Using the 1 675 gauge data from National Meteorological Information Center and the NCEP/NCAR rean-alysis data,the pentad mean averaged precipitation index which can eliminate the regional differences between gau-ges is defined.The rotated empirical orthogonal function decomposition (REOF)is applied to investigate the sea-sonal march of the pentad mean precipitation over the entire China.We obtain two leading modes (e.g.the South and North mode)and their time coefficients.The second mode of REOF presents well the Jiangnan Rainy Season (JRS).Given the consistence of three independent criterion,e.g.,the seasonal process of pentad mean precipitati-on,the interannual variability of precipitation index seasonal variation (April -June mean minus June-August mean)and the interannual variability of mean state of rainy season (April-June)in south of China (south of 31° Nand east of 110°E),the overlap region of these three is objective defined as the geographic region of JRS.Using three variables in the defined geographic region of JRS,e.g.,the rainfall index,regional 925 hPa meridional wind and the western North Pacific subtropical high ridge line position at 500 hPa,the onset and retreat dates of JRS from 1961 to 2012 are determined objectively.The purposes of this paper are to provide reference for monitoring JRS and scientific basis for its prediction.