Sea surface temperature anomalies in the South China Sea during mature phase of ENSO

Based on the 18-year(1993–2010) National Centers for Environmental Prediction optimum interpolation sea surface temperature(SST) and simple ocean data assimilation datasets,this study investigated the patterns of the SST anomalies(SSTAs) that occurred in the South China Sea(SCS) during the mature phase of the El Ni?o/Southern Oscillation.The most dominant characteristic was that of the outof-phase variation between southwestern and northeastern parts of the SCS,which was influenced primarily by the net surface heat flux and by horizontal thermal advection.The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during El Ni?o episodes.Conversely,it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during El Ni?o episodes led to the development of the positive SSTA in the southwestern SCS.     

不同SST资料在海南岛和北部湾珊瑚白化预警中的适用性比较

近年来，受全球气候变化及极端天气的影响，全球范围频繁出现珊瑚礁白化现象，遥感SST已广泛应用于珊瑚白化的监测和预警中。海南岛近岸及北部湾海域的珊瑚礁近年也倍受白化压力，然而，遥感SST在海南岛近岸及北部湾海域珊瑚白化预警中的适用性尚不清楚。为此，本研究比较了3种常用的遥感SST数据（OISST、GHRSST和CoralTemp）在研究海域的异同及其在夏季珊瑚白化预警中的适用性。结果表明，GHRSST的SST最高、CoralTemp次之、OISST最低，OISST的偏差在2013年以前比较明显，GHRSST和CoralTemp在2003年之后比较接近；与浮标的现场观测值相比，2006—2020年CoralTemp的平均偏差和均方根误差分别为0.03 ℃和0.92 ℃，GHRSST为0.08 ℃和0.96 ℃，OISST为-0.25 ℃和1.21 ℃，CoralTemp在研究区域内更为准确；3种遥感SST计算的DHW与使用现场SST计算的趋势一致，CoralTemp的结果更为接近现场SST。因此，3种遥感SST资料中，CoralTemp相对来说更适用于研究海域。     

Interannual to decadal variation of spring sea level anomaly in the western South China Sea

Satellite observations of sea level anomalies(SLA) from January 1993 to December 2012 are used to investigate the interannual to decadal changes of the boreal spring high SLA in the western South China Sea(SCS) using the Empirical Orthogonal Function(EOF) method. We find that the SLA variability has two dominant modes. The Sea Level Changing Mode(SLCM) occurs mainly during La Ni?a years, with high SLA extension from west of Luzon to the eastern coast of Vietnam along the central basin of the SCS, and is likely induced by the increment of the ocean heat content. The Anticyclonic Eddy Mode(AEM) occurs mainly during El Ni?o years and appears to be triggered by the negative wind curl anomalies within the central SCS. In addition, the spring high SLA in the western SCS experienced a quasi-decadal change during 1993–2012; in other words, the AEM predominated during 1993–1998 and 2002–2005, while the La Ni?a-related SLCM prevailed during 1999–2001 and 2006–2012. Moreover, we suggest that the accelerated sea level rise in the SCS during 2005–2012 makes the SLCM the leading mode over the past two decades.     

2011年西北太平洋海平面异常及其与拉尼娜和负印度洋偶极子的联系

西北太平洋海平面异常模态在纯拉尼娜事件与拉尼娜和负印度洋偶极子（IOD）事件同时发生时表现出完全不同的形态。在纯拉尼娜事件期间，西北太平洋海平面呈现显著的正异常；而2010/2011拉尼娜事件期间西北太平洋海平面明显降低，呈显著的负异常，其与印度洋负IOD事件密切相关。研究结果表明，负IOD事件能在热带西太平洋驱动显著的西风异常，由此减弱了拉尼娜峰值期间西北太平洋海平面正异常。同时，在负IOD峰值期的9月，在日经线附近存在显著的风应力旋度正异常，激发负的海平面异常以Rossby波的形式向西传播，并在第二年6月抵达菲律宾以东海域，维持并加强该海域海平面负异常，进而对北赤道流分叉点位置及输运产生重要的影响。     

层云加热对热带大气季节内振荡的影响

本文研究了层云降水加热对于激发热带大气季节内振荡(Madden-Julian oscillation,简称MJO)所起到的作用.将层云加热作用引入到非线性的CISK (Conditional Instability of Second Kind)-Kelvin波方程组,并分别利用截谱方法和四阶Runge-Kutta方法...