一个重构的153年热带太平洋次表层上卷海温资料

次表层上卷海温对改进ENSO(厄尔尼诺-南方涛动,El Ni o-Southern Oscillation)模拟水平及ENSO年代际变化均具有重要作用。利用一个中等复杂程度耦合模式(intermediate coupled model,简称ICM)和Nudging(张弛逼近)同化方法,重构了1856—2008年间热带太平洋地区的次表层上卷海温。统计检验表明,重构的次表层上卷海温与近50年的3种分析资料间具有较高的相关性和较小的均方根误差。此外,通过此重构的次表层上卷海温资料重新驱动ICM模式,模拟得到的海表温度距平(sea surface temperature anomaly,简称SSTA)可以真实地反映出ENSO的年际和年代际变化,表明此重构的次表层上卷海温资料可用于气候研究,特别是用于ENSO的大尺度低频变化或年代际气候变化研究。

A reconstructed subsurface entrainment temperature data over the tropical Pacific for the past 153y

The temperature of subsurface water entrained into the mixed layer(Te) is very important to improve El Ni o-Southern Oscillation(ENSO) simulations and modulated ENSO decadal variability.Based on an intermediate coupled model(ICM) and nudging data assimilation method,a long-term monthly-mean Te dataset is reconstructed over the tropical Pacific for the period of 1856 2008.The verification results show that the reconstructed Te data have high correlations and small root mean square(RMS) errors with three analysis Te dataset in the last 50 years.Also,the simulated sea surface temperature(SST) anomalies from the ICM,forced by the reconstructed Te dataset,can simulate realistic interannual and decadal variability of ENSO very well.This indicates that the reconstructed Te dataset is useful for climate research,especially for the large-scale low frequency or decadal variability of ENSO.