Predictability of a Stepwise Shift in Pacific Climate during the Late 1990s in Hindcast Experiments Using MIROC
Predictability of a Stepwise Shift in Pacific Climate during the Late 1990s in Hindcast Experiments Using MIROC
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DOI：
10.2151/jmsj.2012-a01
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发表时间：
2012-02-01
影响因子：
3.1
通讯作者：
Jin, Fei-fei
中科院分区：
文献类型：
--
作者：
Chikamoto, Yoshimitsu;Kimoto, Masahide;Jin, Fei-fei
利用低、中、高分辨率的海洋-大气耦合模式MIROC，在后预报试验中检验了太平洋海表温度(SST)在年代际时间尺度上的可预测性。在这些后预报实验中，初始条件是利用观测到的海洋温度和盐度从异常同化过程中获得的，同时根据气专委的浓度情景规定自然和人为的强迫。我们的后预报实验表明，西副热带太平洋、印度洋和热带到北大西洋的海温是可预测的。以前的研究考察了印度洋和大西洋的海温可预报性，但还没有对西亚热带太平洋的海温可预报性进行评估。在西太平洋，从20世纪90年代初到21世纪初，观测到的两个半球副热带海温异常迅速增加。虽然西副热带太平洋海温变暖的部分原因是全球变暖信号，但我们在1995年或1996年建立的模式的预报倾向于模拟海温升高和与之相关的降水变化的模式。这种90年代后期的大气候变化，可能与近期台湾台风频次增多、近期研究报告的东亚季风减弱等现象有关。
Sea surface temperature (SST) predictability in the Pacific on decadal timescales is examined in hindcast experiments using the coupled atmosphere-ocean model MIROC with low, medium, and high resolutions. In these hindcast experiments, initial conditions are obtained from an anomaly assimilation procedure using the observed oceanic temperature and salinity while prescribing natural and anthropogenic forcing based on the IPCC concentration scenarios. Our hindcast experiments show the predictability of SST in the western subtropical Pacific, the Indian Ocean, and the tropics to the North Atlantic. Previous studies have examined the SST predictability in the Indian Ocean and the Atlantic, but SST predictability in the western subtropical Pacific has not been evaluated. In the western Pacific, the observed SST anomalies in the subtropics of both hemispheres increased rapidly from the early 1990s to the early 2000s. While this SST warming in the western subtropical Pacific is partly explained by global warming signals, the predictions of our model initialized in 1995 or 1996 tend to simulate the pattern of the SST increase and the associated precipitation changes. This large climate change around the late 1990s may be related to phenomena such as the recent increase in the typhoon frequency in Taiwan and the weakened East Asian monsoon reported by recent studies.