CAJ | 학술논문

利用区域气候模式RegCM3对东亚夏季风及其中的大气低频振荡(LFO)进行了模拟研究.(1)进行控制试验,借助Lanczos带通滤波等方法分析了实测及模拟结果LFO强度和传播等特征,检验RegCM3对夏季风LFO的模拟能力;(2) 通过增、减南海表面海温两个敏感试验探讨海温异常变化对LFO各特征的影响,并探究异常海温下的LFO与季风爆发时间的可能联系.结果表明:季风LFO强值集中在低纬地区,低纬夏季强冬季弱,高纬则相反.季风爆发前后的发生南传向北传的转换.模式RegCM3对季风区LFO基本特征有较好的把握,但高纬地区偏强.南海异常增(减)温有利于季风提前(推迟)爆发,也有利于LFO传向发生转换时间的提前(推迟).说明季风爆发时间与LFO传向转换存在一定联系.两个试验均有使振荡能量大值区南移的趋势,且通过LFO的变化造成较高纬地区季风后期的气候异常.
이용구역기후모식RegCM3대동아하계풍급기중적대기저빈진탕(LFO)진행료모의연구.(1)진행공제시험,차조Lanczos대통려파등방법분석료실측급모의결과LFO강도화전파등특정,검험RegCM3대하계풍LFO적모의능력;(2) 통과증、감남해표면해온량개민감시험탐토해온이상변화대LFO각특정적영향,병탐구이상해온하적LFO여계풍폭발시간적가능련계.결과표명:계풍LFO강치집중재저위지구,저위하계강동계약,고위칙상반.계풍폭발전후적발생남전향북전적전환.모식RegCM3대계풍구LFO기본특정유교호적파악,단고위지구편강.남해이상증(감)온유리우계풍제전(추지)폭발,야유리우LFO전향발생전환시간적제전(추지).설명계풍폭발시간여LFO전향전환존재일정련계.량개시험균유사진탕능량대치구남이적추세,차통과LFO적변화조성교고위지구계풍후기적기후이상.
The regional climate model RegCM3 is used here to study the East Asian summer monsoon and its atmospheric low-frequency oscillation(LFO). First, a control experiment was conducted to analyze the intensity and other characteristics of LFO with the help of Lanczos pass filter of both NCEP data and simulation results, and test the simulation capability of RegCM3 with regard to LFO during the summer monsoon. Secondly, two sensitivity tests were performed in which the surface temperature of the South China Sea was either increased or decreased to discuss the change of LFO and possible relationships between LFO and monsoon onset time. The results show that the intensity of LFO was high mainly in the low latitudes and stronger in summer than in winter, and otherwise was true for high latitudes. There was a change in the propagation direction of LFO from southward to northward around the time of monsoon onset. RegCM3 has the ability of simulating the basic characteristic of LFO, but performs better in high latitudes. Anomalously high(low) temperature of South China Sea is favorable for bringing the outbreak of the monsoon forward (backward), while anomalously high(low) temperature is also favorable for pushing the shift of LFO propagation direction forward(backward). It shows that there must be some relationships between the onset of monsoon and LFO change in propagation direction. Both tests tend to move areas of strong oscillation southward and affect the climate anomalies of high latitudes during the late monsoon stage through LFO changes.