摘要:
基于传递熵概念和方法定义气象场的信息源特征度、信息汇特征度和信息传输平衡特征度。使用海表温度和高度场资料计算海气相互作用过程中的信息传递。侧重分析赤道中东太平洋(20?S-20?N,170?E-100?W)与热带地区、北半球和南半球中高纬度地区大气之间的信息传递,给出信息传递的区域和全球分布特征；并提取海表温度指数和高度场指数分析赤道中东太平洋与大气信息传递特征的季节变化和年代际变化。研究结果表明,海洋信息源主要分布在热带地区,大气信息汇主要分布在中纬度地区,从热带地区到中纬度地区,海洋对大气的强迫作用在减弱,而大气对海洋的强迫作用在增强；不同区域不同层次的高度场对赤道中东太平洋海表温度有着不同的响应,热带中东太平洋上空高度场最大延迟为4个月。欧亚大陆中部上空和北美大陆上空高度场均随时间延迟呈现波动性变化：欧亚大陆中部上空高度场随时间延迟呈现增强的趋势,而北美大陆上空高度场随时间延迟呈现减弱的趋势。海表温度指数对热带中东太平洋上空850 hPa和欧亚大陆中部上空500 hPa高度场指数的传递熵以2000 s 最弱,而海表温度指数对北美大陆上空700 hPa高度场指数的传递熵以2000 s最强。表明不同年代际背景下不同区域大气对赤道中东太平洋海表温度异常的响应是不同的。然而不同季节的响应却十分相似：冬季最强,秋季次之,春季再次,夏季最弱。
Abstract:
In this article, information source characteristic degree, information sink characteristic degree and transfer equilib-rium characteristic degree are defined based on transfer entropy. According to the definition, the information transfer in air-sea interaction is examined with sea surface temperature (SST) and geopotential height (GH). And the information transfer between central and eastern equatorial Pacific (20?S-20?N, 170?E-100?W) and tropics (20?S-20?N), and that between atmospheres in high latitude regions of northern hemisphere (north of 20?N) and southern hemisphere (south of 20?S) are analyzed too. In addition, decadal changes and seasonal differences in information transfer between central and eastern equatorial Pacific ocean and atmosphere are discussed by the defined indices of SST and HG. In a word, the information source distribution of ocean is mainly in tropics and the information sink distribution of atmosphere is mainly in mid-latitude. From the low-latitude to the mid-latitude, the ocean forcing the atmosphere is weakened while the atmosphere forcing the ocean is strengthened. Significant regional difference, decadal change and seasonal difference exist in information transfer from the tropical ocean to the atmosphere.
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