热带气象学报2024，Vol.40Issue(1)：85-100,16.DOI:10.16032/j.issn.1004-4965.2024.010
季节内印度洋-西太平洋对流涛动对次季节-季节尺度大气可预报性的影响
Impact of the Intraseasonal Indo-west Pacific Convective Oscillation on Subseasonal-seasonal Atmospheric Predictability
摘要
Abstract
This work quantifies the contribution of seasonal IPCO to S2S atmospheric predictability by using the nonlinear local Lyapunov exponent and conditional nonlinear local Lyapunov exponent to estimate the forecastable period of intraseasonal IPCO and RMM index,and investigates the variation pattern of the spatial distribution of S2S predictability limit under the evolution of intraseasonal IPCO.The results show that:(1)Compared with the RMM index,the intraseasonal IPCO index is more predictable,with predictability limit of about 31 days,which is more than 2 weeks higher than the RMM index.(2)The S2S atmospheric predictability is the strongest in the Indo-West Pacific,with predictability limit of more than 30 days,in which the intraseasonal IPCO is one of the main predictability sources in this region,with its contribution reaching more than 6 days.(3)With the evolution of intraseasonal IPCO,the S2S atmospheric predictability of the Indian Ocean western Pacific region has a spatial structure change,manifesting as the propagation and oscillation of predictability period anomalies.The S2S atmospheric predictability anomalies propagate along the intraseasonal IPCO paths,one starting from the equatorial western and central Indian Ocean northward to the Indian Peninsula,and one propagating eastward through the oceanic continents to the equatorial western Pacific Ocean and then northward to southern Japan.Meanwhile,the propagation of the predictability anomaly shows reverse variability in the eastern Indian Ocean and the western Pacific Ocean,forming an east-west polar oscillation.When the intraseasonal IPCO develops toward the positive phase,the eastern Indian Ocean has stronger predictability and the western Pacific Ocean has weaker predictability,and vice versa.The development(decline)of intraseasonal IPCO can make the S2S atmosphere in the East Indian Ocean(West Pacific)more predictable,and the model forecast skill has more room for improvement.关键词
季节内印度洋-西太平洋对流涛动(IPCO)/S2S尺度可预报性/热带季节内振荡/非线性局部Lyapunov指数Key words
intraseasonal Indo-West Pacific convection oscillation(IPCO)/S2S predictability/tropical intraseasonal oscillations/nonlinear local Lyapunov exponent分类
天文与地球科学引用本文复制引用
胡榕,李建平,侯兆禄..季节内印度洋-西太平洋对流涛动对次季节-季节尺度大气可预报性的影响[J].热带气象学报,2024,40(1):85-100,16.基金项目
国家自然科学重点基金(42130607) （42130607）
崂山实验室科技创新项目(LSKJ202202600) （LSKJ202202600）
山东省自然科学基金重大基础研究项目(ZR2019ZD12) （ZR2019ZD12）
国家自然科学基金(42005049)共同资助 （42005049）
