CAJ | 학술논문

使用多种长期观测和再分析资料，分析了北半球冬季阿留申低压和冰岛低压相关关系的年代际变化。结果表明，两低压存在显著的负相关关系，使北太平洋和北大西洋海平面气压形成跷跷板式的变化（Aleutian Low-Icelandic Low Seesaw, AIS）。此外，AIS还存在显著的年代际变化，在1935～1949年和1980年后较为显著，其余时期并不显著。对1980年代的年代际转变分析表明，太平洋年代际振荡（Pacific Decadal Oscillation，PDO）在1970年代末的位相转变是AIS这次年代际转变的主要原因。PDO由负位相转变为正位相，使全球大部分大洋海表温度升高，而北太平洋海表温度降低，两低压显著变深，低压南部西风增强，从而通过 Rossby 波的频散效应使两低压强度形成显著负相关。1930年代中期的年代际转变与此类似，但强度较弱。同时，年代际背景的变化也影响到两低压的年际变化。在给定海表温度和海冰分布的驱动下，大气环流模式IAP AGCM4能基本模拟出AIS年代际转变的过程和机理，但仍存在一些偏差。
사용다충장기관측화재분석자료，분석료북반구동계아류신저압화빙도저압상관관계적년대제변화。결과표명，량저압존재현저적부상관관계，사북태평양화북대서양해평면기압형성교교판식적변화（Aleutian Low-Icelandic Low Seesaw, AIS）。차외，AIS환존재현저적년대제변화，재1935～1949년화1980년후교위현저，기여시기병불현저。대1980년대적년대제전변분석표명，태평양년대제진탕（Pacific Decadal Oscillation，PDO）재1970년대말적위상전변시AIS저차년대제전변적주요원인。PDO유부위상전변위정위상，사전구대부분대양해표온도승고，이북태평양해표온도강저，량저압현저변심，저압남부서풍증강，종이통과 Rossby 파적빈산효응사량저압강도형성현저부상관。1930년대중기적년대제전변여차유사，단강도교약。동시，년대제배경적변화야영향도량저압적년제변화。재급정해표온도화해빙분포적구동하，대기배류모식IAP AGCM4능기본모의출AIS년대제전변적과정화궤리，단잉존재일사편차。
Based on long-term observational and reanalysis data, this study focuses on the decadal variation in the correlation between the Aleutian low (AL) and the Icelandic low (IL) during boreal winter. The results show a clear seesaw pattern in sea level pressure between the North Pacific and North Atlantic due to a negative correlation between the AL and the IL (AIS). In addition, the AIS is significant from 1935-1949 and after 1980 while it is not so significant in other periods, i.e., there exists a decadal variation in the AIS. Results also indicate that the phase transition of the Pacific decadal oscillation (PDO) during the late 1970s played a major role in the decadal shift of the AIS in the 1980s. The phase transition of the PDO from a negative to a positive phase leads to enhanced sea surface temperature (SST) over the global oceans and a reduced SST in North Pacific. In the meantime, the two lows are also deepened with a strengthened westerly on the south flanks of the lows. As a result, a negative correlation between the AL and the IL tends to become significant through the Rossby wave dispersive process. The decadal shift in the mid-1930s was much the same but with weaker intensity. We also noted that the interannual variability of the lows is influenced by the decadal climate background. Driven by the observed SST and sea ice, the IAP AGCM4 generally simulates the observed decadal shift of the AIS and related mechanisms although there are some biases in the model.