台风强度模拟的海温目标观测研究

根据非线性强迫奇异向量（NFSV）型海温（SST）强迫误差识别的敏感性特征，通过观测系统模拟试验（OSSE）确定了12个热带气旋（TC）的强度模拟的海温目标观测最优布局。NFSV型SST强迫误差敏感区一般沿着台风移动路径，主要位于台风快速增强阶段。结果表明，在NFSV型SST强迫目标观测敏感区内以90 km间隔加密海温观测，这些额外观测能够更加有效地改善TC强度的模拟技巧；与空间范围更大的非敏感区相比，在NFSV型SST强迫目标观测敏感区内进行目标观测，能够更加有效地改进TC强度的模拟能力，而当非敏感区内的局地观测区域逐步接近目标观测敏感区时，该局地区域的加密观测对TC强度模拟改善程度也逐步提高。进一步研究表明，上述目标观测对台风强度模拟水平的改善尤以NFSV型SST强迫误差大值区所对应的TC快速增强阶段最为明显。所以，在由NFSV型SST强迫误差确定的目标观测敏感区和敏感时段内加密观测，对台风强度模拟能力的提高最有效，而且在敏感区内以合适的间隔实施外场观测是最经济的观测策略。

Target Observation of Sea Surface Temperature for Tropical Cyclone Intensity Simulation

According to the Nonlinear forcing singular vector type (NFSV-type) sea surface temperature (SST) forcing errors of 12 tropical cyclones (TCs), the optimal target observation deployment of the sea surface temperature is identified through the observing system simulation experiments (OSSEs). The sensitive area of NFSV-type SST forcing errors occurs along the track of TCs and during the intensification phase of TCs. Results of OSSEs show that the additional observations deployed in the sensitive area with intervals of 90 km effectively improve the simulation of the TC intensity. Compared with the observations deployed in nonsensitive areas, the target observations in the sensitive areas of NFSV-type SST forcing errors can more effectively improve the simulation of the TC intensity. When the local target observation area in the nonsensitive area reaches the sensitive area, the additional observations will gradually improve the simulation of the TC intensity. In particular, further experiments show that the simulation of the TC intensity improves more significantly when the target observations deployed during the intensification phase correspond to the periods of the occurrence of the large-value region of NFSV. Therefore, the additional observations in the target area identified using NFSV-type SST forcing errors can improve the simulation of the TC intensity most effectively, and the suitable deployment of observations in the sensitive area during the sensitive periods is the most economical observation strategy.