Spatial and temporal patterns linking southern low and high latitudes during South Pacific warm and cold events
Spatial and temporal patterns linking southern low and high latitudes during South Pacific warm and cold events
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南太平洋暖冷事件期间连接南部低纬度和高纬度的时空模式
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
G. McGregor
中科院分区：
文献类型：
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作者：
R. Houseago;G. McGregor
本文研究了南半球以冷暖事件为中心的24个月500 hPa高度距平的一次谐波的位相和幅度，以确定在太平洋暖（El Nino）和冷（La Nina）事件期间低纬和高纬500 hPa气压距平是否有联系。研究结果显示，在寒冷事件期间，印度洋-东南极区域以东经60度为中心的压力异常存在联系。与冷事件相反，在这一地区，以及在南极半岛地区的暖事件信号，缺乏清晰度，因为相当大的暖事件的变化。然而，在暖事件期间，沿南太平洋辐合带（SPCZ）沿着出现明显的异常波列。这与500 hPa异常相位中的强烈纬向对比相匹配，使得低纬度和高纬度与中纬度异相。这种太平洋/南美（PSA）模式类似于太平洋/北美（PNA）模式，被认为在厄尔尼诺-南方涛动（ENSO）信号从低纬度到高纬度的传输中发挥了重要作用。
The phase and magnitude of the first harmonic of cold and warm event-centred 24-month 500 hPa height anomalies over the Southern Hemisphere are investigated in order to establish whether low and high latitude 500 hPa pressure anomalies are linked during Pacific Ocean warm (El Nino) and cold (La Nina) events. Study results revealed a linkage of pressure anomalies centred on 60°E in the Indian Ocean-East Antarctic region during cold events. In contrast to cold events, warm event signals in this area, as well as in the Antarctic Peninsula region, lack clarity because of considerable warm event variability. During warm events, however, a clear wave train of anomalies occurs along the South Pacific Convergence Zone (SPCZ). This is matched with a strong meridional contrast in the phase of 500 hPa anomalies such that low and high latitudes are out of phase with mid-latitudes. This Pacific/South American (PSA) pattern resembles the Pacific/North American (PNA) pattern, and is thought to play a major role in the transport of El Nino-Southern Oscillation (ENSO) signals from low to high latitudes.