2011年“洛克”和“桑卡”双台风预报效果的初值试验研究

采用南海台风模式，对2011年业务预报误差较大的台风“洛克”（1115）和“桑卡”（1116）双台风的初值方案进行试验和研究，目的在于寻求改进预报的线索，从而提升台风模式性能。针对“洛克”和“桑卡”台风设计了几组初值方案对比试验，结果表明，仅对弱台风“桑卡”进行重定位和bogus的初值处理，与对双台风都进行初值处理相比较，两台风的路径预报误差减小。分析认为仅对弱台风作初值处理以改善其涡旋环流的影响是该双台风路径预报得以改进的原因。对2011—2012年所有弱台风进行批量预报试验，结果表明对弱台风采用重定位和bogus的初值处理，台风路径预报和强度预报的误差减小。对弱台风进行重定位和bogus初值处理，可改善模式对弱台风的预报效果。此外，目前南海台风模式中现有的bogus方法构造的涡旋相对于弱台风而言云顶偏高，可考虑发展针对弱台风的涡旋模型。 

INVESTIGATION ONINITIAL SCHEMES FOR BINARY TYPHOONS ROKE AND SONCA IN 2011

Based on the Tropical Region Atmospheric Modeling System for South China Sea (TRAMS), Typhoon Roke (1115) and Sonca (1116) in 2011 which have large forecast errors in numerical operation prediction, have been selected for research focusing on the initial scheme and its influence on forecast.The purpose is to find a clue for model improvement and enhance the performance of the typhoon model. Several initialization schemes have been designed andthe corresponding experimentshave beendone for Typhoon Roke and Sonca. The results show that the forecast error of both typhoons' track and intensity are less using the initial scheme of relocation and bogus just for the weak Typhoon Sonca, compared with using the scheme for both typhoons. By analysis the influence of the scheme on weak typhoon vortex circulation may be the reason that leads to the improvement. All weak typhoons in 2011 to 2012 are selected for tests. It comes to the conclusion that the initial scheme of relocation and bogus can reduce the error of track and intensity forecast. Besides, the height of cloud top in typhoon vortex constructed by bogus is too high according to weak typhoon.It is feasible to develop a bogus which is suitable for weak typhoon.