1.Key laboratory of Meteorological Disaster of Ministry of Education,Nanjing University of Information Science Technology;2.Henan Meteorological Observation Data Center;3.Meteorological Center of CAAC Southwest Air Traffic Administration
Whether perturbation can accurately describe the uncertainty of atmospheric motion is the core issue of ensemble forecasting research. A reasonable perturbation structure and amplitude should be able to reflect the characteristics of forecast error about the state of atmospheric motion. For solving the problems of insufficient spread, recognizability and reliability of perturbation in GRAPES regional ensemble forecast, this paper designs and develops different schemes to constrain initial ensemble perturbation with analysis error extracted from data assimilation system, in the light of the relationship of structure and evolution characteristics between ensemble perturbation and the forecast errors of weather systems at different scales. This study analyzes the spatial physical structure and spatiotemporal evolution characteristics of ensemble perturbation, spread and perturbation energy, in order to comprehensively assess the quality and performance of the analysis-constrained schemes. The results show that the schemes can partly identify and adjust the false perturbation in the original forecast. After constraining, the structure and evolution of the perturbation are in better agreement with the development of weather systems at different scales, with higher accuracy to describe the forecasting uncertainty. The feature that spread and perturbation energy increases with the forecast time is also more significant, especially in the early period.