由热带气旋进入海洋近惯性运动能量的估计  

ESTIMATING THE ENERGY FLUX FROM THE TROPICAL CYCLONES TO OCEAN NEAR-INERTIAL MOTIONS

作　　者：钱奇峰[1] 江静[1] 

机构地区：[1]南京大学大气科学学院,江苏南京210093

出　　处：《热带气象学报》2012年第4期471-477,共7页Journal of Tropical Meteorology

基　　金：国家自然科学基金(40775043);教育部博士点基金(200802840022)共同资助

摘　　要：根据美国联合台风警报中心(JTWC)最佳路径资料,采用Bogus方案构造了西北太平洋2000—2006年包含热带气旋的风场,作为海洋模式POM的风应力驱动,研究了西北太平洋热带气旋进入海洋近惯性运动的能量分布、传播等特征。结果表明,考虑热带气旋后西北太平洋近惯性能量增加了三倍多,约为5.14×10-3TW,其中大部分能量在低纬产生,且近半数存在于50 m以上,85%发生在海表面至水下500 m,还有15%能达到更深层次。热带气旋产生的近惯性能量在下传时,其传播方向和速度随深度呈明显差异:在上混合层,能量基本均匀,平均能在此滞留约2 d然后下传;在200 m以上,能量以垂直下传为主,下传速度非常快;在200～800m左右,能量下传路径发生右偏,下传速度较慢;在800 m以下,下传速度重新加快,并向TC路径靠近。Wind-work on near-inertial motions of tropical cyclones and corresponding ocean near-inertial energy changes are studied using a regional ocean model. Two model runs are well conducted with differences only in the wind forcing used. One model run is forced by the wind stress calculated from NCEP 10-m winds, and the other is conducted with simulated wind fields which are generated by adding tropical cyclones to the NCEP winds. It is shown that the tropical cyclones enhance the energy flux input to near-inertial motions by 5.14×10^-3TW, which is more than a threefold increase compared to that of the NCEP winds. About a half of this enhanced energy exists in the upper 50 m layer, and this rate accumulates upto 85% in the upper 500 m layer. When this energy propagates downward, the feature is quite different in depth. In the mixing layer, the near-inertial energy mixes well, and about two days after the cyclone passage it starts to propagate downward. From the base of the mixing layer to the 200 m level, the energy travels fast and is mainly vertically downward. In the middle 200 m to near 800m levels, it travels more slowly, with a trend of rightward bias off the cyclone track. Below 800 m, the energy propagation speeds up again and gets close to the track.

关 键 词：气候学 近惯性运动 数值模拟 热带气旋 

分 类 号：P444[天文地球—大气科学及气象学]