NUIST地球系统模式模拟ENSO对西北太平洋热带气旋活动的影响

Impact of ENSO on Tropical Cyclone Activities in Northwest Pacific Simulated by the NUIST Earth System Model

地球系统模式已经逐步成为研究热带气旋(TC)活动气候变化的重要工具之一,之前的研究发现南京信息工程大学地球系统模式(NESM)高分辨率版本可以较好地模拟全球海温分布及TC活动的气候特征。本研究进一步分析了NESM地球系统模式模拟西北太平洋TC活动的年际变化,并与1967~2016年观测的TC活动进行对比。NESM模式高分辨率版本能够较好地模拟西北太平洋平均海温及与ENSO事件联系的海温异常变化特点,对El Nino事件发生时西北太平洋TC的生成频数和路径分布的模拟较好,也能模拟El Nino年TC生成位置比La Nina年偏东的特征,但是未能模拟出TC平均生命周期和Nino3.4地区海温的相关性。并且模式模拟的La Nina年TC的生成位置偏东,主要原因是模拟La Nina年季风槽平均位置偏东。研究结果有助于进一步改进NESM模式和利用NESM模式研究TC活动。

An Earth system model is an important tool for studying the TC(tropical cyclone) activities affected by climate change. Previous studies have shown that the high-resolution version of the NUIST Earth system model(NESM)can simulate the global SST distribution and climate characteristics of the TC activity. Compared to the TC activity observed from 1967 to 2016, this study analyzed the interannual variability of the TC activity in the Northwest Pacific Ocean simulated by the NESM model. The results show that the high-resolution version of the NESM model can simulate the mean SST in the Northwest Pacific and the SST anomalies associated with ENSO events. This model could simulate the generation frequency and the path distribution of TCs in the Northwest Pacific when El Nino events occur. The simulation showed that the position of TCs in El Nino years was more easterly than in the La Nina years. However, the correlation between the mean life of TC and Nino3.4 SST could not be simulated. Moreover, the generation position of TCs in La Nina years simulated by the model is easterly than observation, mainly because the average position of the monsoon trough in the simulated La Nina years is eastward. These results can help improve the NESM model studying TC activities.