热带气象学报
熱帶氣象學報
열대기상학보
2001年
2期
97-108
,共12页
前后汛期%旱涝%成因%预测
前後汛期%旱澇%成因%預測
전후신기%한로%성인%예측
根据广东省86个气象站降水量资料，用正态化Z指数对前、后汛期旱涝等级进行了划分。前汛期旱涝年对比分析表明：西太平洋副高造成的南海地区较强偏南风和较强东亚大槽以及较强南支西风急流（有利于中纬度冷空气南侵）之间的相互作用是影响广东前汛期降水偏多的直接原因。广东前汛期偏旱的主要原因是冷空气偏弱。西太平洋暖池海温变化是这种相互作用的重要影响因子，暖池海温偏高（低），广东前汛期正常偏旱（涝）。前期12～2月西太平洋暖池海温是前汛期旱涝变化的重要强信号之一；预测前汛期旱涝时应特别关注两极极涡的强度变化和中纬度地区位势高度变化。后汛期旱涝年份对比分析表明：亚洲夏季风系统偏强（弱）是造成广东省后汛期偏涝（旱）的最重要因素，登陆广东的热带气旋个数对后汛期降水的影响也比较大。还探讨了后汛期旱涝的预测问题，提出前期5月份北太平洋东部地区500 hPa位势高度距平是预测后汛期旱涝的重要强信号，其位势高度为正距平，则广东后汛期偏旱，负距平则偏涝。南半球中高纬地区大气环流变化通过对印度夏季风的影响从而影响后汛期旱涝的变化。
根據廣東省86箇氣象站降水量資料，用正態化Z指數對前、後汛期旱澇等級進行瞭劃分。前汛期旱澇年對比分析錶明：西太平洋副高造成的南海地區較彊偏南風和較彊東亞大槽以及較彊南支西風急流（有利于中緯度冷空氣南侵）之間的相互作用是影響廣東前汛期降水偏多的直接原因。廣東前汛期偏旱的主要原因是冷空氣偏弱。西太平洋暖池海溫變化是這種相互作用的重要影響因子，暖池海溫偏高（低），廣東前汛期正常偏旱（澇）。前期12～2月西太平洋暖池海溫是前汛期旱澇變化的重要彊信號之一；預測前汛期旱澇時應特彆關註兩極極渦的彊度變化和中緯度地區位勢高度變化。後汛期旱澇年份對比分析錶明：亞洲夏季風繫統偏彊（弱）是造成廣東省後汛期偏澇（旱）的最重要因素，登陸廣東的熱帶氣鏇箇數對後汛期降水的影響也比較大。還探討瞭後汛期旱澇的預測問題，提齣前期5月份北太平洋東部地區500 hPa位勢高度距平是預測後汛期旱澇的重要彊信號，其位勢高度為正距平，則廣東後汛期偏旱，負距平則偏澇。南半毬中高緯地區大氣環流變化通過對印度夏季風的影響從而影響後汛期旱澇的變化。
근거광동성86개기상참강수량자료，용정태화Z지수대전、후신기한로등급진행료화분。전신기한로년대비분석표명：서태평양부고조성적남해지구교강편남풍화교강동아대조이급교강남지서풍급류（유리우중위도랭공기남침）지간적상호작용시영향엄동전신기강수편다적직접원인。엄동전신기편한적주요원인시랭공기편약。서태평양난지해온변화시저충상호작용적중요영향인자，난지해온편고（저），엄동전신기정상편한（로）。전기12～2월서태평양난지해온시전신기한로변화적중요강신호지일；예측전신기한로시응특별관주량겁겁와적강도변화화중위도지구위세고도변화。후신기한로년빈대비분석표명：아주하계풍계통편강（약）시조성광동성후신기편로（한）적최중요인소，등륙엄동적열대기선개수대후신기강수적영향야비교대。환탐토료후신기한로적예측문제，제출전기5월빈북태평양동부지구500 hPa위세고도거평시예측후신기한로적중요강신호，기위세고도위정거평，칙엄동후신기편한，부거평칙편로。남반구중고위지구대기배류변화통과대인도하계풍적영향종이영향후신기한로적변화。
With the rainfall data in Guangdong, the grades of drought and flood in both first stage (Apr.～June) and second stage (Jul.～Sep.) of rain season in Guangdong have been partitioned with Z-index. The grade series in the first stage have 24 years, 6～8 years and 3～4 years cycle. The grade series in the second stage have a 10-year cycle, which have been found by Morlet wavelet transform. With compariton between drier and wetter years in the first stage, it has been found that the major reason of rainfall more than normal is the interaction between the stronger southerly in South China Sea and deeper East Asia trough and stronger high jet in East Asia. The major reason for less-than-normal rainfall is that cold air is weaker. The SST in warm pool of western Pacific has an important impact on that interaction. The warmer the SST, the less the rainfall will be in Guangdong. In the paper, we also discuss the forecast technology. It suggests that SST in the warm pool may play as a significant signal for forecasting the drought and flood in the first stage. The atmospheric circulation anomalies in the middle and higher latitude of both Hemispheres shall be taken more notice for forecasting the drought and flood. With compariton between drier and wetter years in the second stage, it has been found that the stronger (weaker) Asia summer monsoon system is a most important factor for the wetter (drier) and the number of landing typhoon is also another influencing factor. It suggests that the height anomalies of preceding May at 500 hPa in (40～50 °N，160～140 °W) may play as an significant signal for forecasting the drought and flood in the second stage. The atmospheric circulation anomalies in the middle and higher latitude of Southern Hemisphere can affect the drought and flood through their impact on the Indian summer monsoon.
