气象学报2016，Vol.74Issue(2)：176-188,13.DOI:10.11676/qxxb2016.020
一次弱弓形飑线后方入流特征的观测分析
The observational analysis of the characteristics of rear inflow in a weak-bow squall line
摘要
Abstract
The mesoscale system-relative rear inflow is a component of mesoscale convective systems.It is characterized by a current of air penetrating through the stratiform precipitation region from the rear side of the storm and plays an important role in the formation of a strong cold pool and mesoscale downdrafts.In this study,we have exploited Doppler radar observations, intensive surface observations and NCEP(National Centers for Environmental Prediction)reanalysis to investigate characteris-tics of the rear inflow in a weak bow echo squall line occurred on 16 May,2012 in Jiangsu Province.The squall line developed under the combined effects of a northeast cold vortex,a large differential temperature advection,a low-level jet and a thermal ridge.Analysis of the system-relative horizontal winds retrieved from radar radial velocity shows that the rear inflow firstly ap-peared in the stratiform region in the middle troposphere,and then extended to the back edge of the convective region during the development stage of the squall line.At the mature stage,the rear inflow occupied a continuous channel extending from middle levels at the back edge of the stratiform region to lower levels at the leading convective region.During the dissipation stage,the rear inflow maximum gradually descended to the ground,where it enhanced the local convergence caused by south-westerly inflows and cold pool outflows.This convergence might trigger the formation of new back-building convective cells, thereby causing the occasional dual-band echo.The rear inflow transported the cold and dry air in the middle level to the middle lower convective region,strengthening evaporative cooling and promoting the generation of intensive cold pool outflows and high surface winds.This result is consistent with that of theoretical studies.Under the influence of the maximum rear inflow near the surface and the newly generated band echoes,the cold pool continued to intensify and led to strong surface winds dur-ing the dissipation stage.Note that the rear inflow well corresponded to the surface mesoscale convergence line.关键词
飑线/后方入流/双带状回波/地面大风Key words
Squall line/Rear inflow/Dual band echo/Surface high wind分类
天文与地球科学引用本文复制引用
康红,费建芳,黄小刚,程小平,孙吉明..一次弱弓形飑线后方入流特征的观测分析[J].气象学报,2016,74(2):176-188,13.基金项目
资助课题国家自然科学基金重点项目（41230421）、国家重点基础研究发展计划（973计划）项目（2013CB430101）。 （）
