暴雨灾害
暴雨災害
폭우재해
TORRENTIAL RAIN AND DISASTERS
2014年
1期
80-86
,共7页
周后福%余政%袁业畅%张杰%祁文
週後福%餘政%袁業暢%張傑%祁文
주후복%여정%원업창%장걸%기문
强风暴%涡旋状回波%风暴参数%中气旋参数%风廓线产品
彊風暴%渦鏇狀迴波%風暴參數%中氣鏇參數%風廓線產品
강풍폭%와선상회파%풍폭삼수%중기선삼수%풍곽선산품
severe storm%vortex-shaped echo%storm parameters%meso-cyclone parameters%wind profile product
2013年4月29日下午皖西南的安庆市和东至县发生了一次冰雹、雷雨大风强天气过程。本文以九江雷达资料为主,辅以GFS预报场和地面资料,重点对风暴单体雷达特征、雷达物理量参数演变规律进行了分析。结果表明:(1)雷达反射率因子图上,强风暴单体为涡旋状回波,回波前沿存在反射率因子高梯度区;速度图上涡旋状回波区对应着连续出现中气旋的现象,说明强风暴单体为具有涡旋形态的超级单体;强风暴顶高于11 km,大于50 dBz的强反射率因子高度超过-20 C层的高度等特征是产生大冰雹的重要指标。(2)风暴和中气旋参数分析表明,冰雹发生在最大反射率因子高度(HT)和风暴顶高(TOP)出现最强值的上升阶段中,最大垂直液态水含量(VIL)为58 kg·m-2,最大反射率因子(DBZM)极值为77 dBz;VIL密度(DVIL)≥4.0 g·m-3的持续时间达1 h以上,其最大值超过6.0 g·m-3。(3)该过程大冰雹产生在最大DVIL值出现后半小时,在DVIL为5.0 g·m-3时且在高梯度区附近出现;大风出现在中气旋持续时间较长和中气旋位置较高的时候。
2013年4月29日下午皖西南的安慶市和東至縣髮生瞭一次冰雹、雷雨大風彊天氣過程。本文以九江雷達資料為主,輔以GFS預報場和地麵資料,重點對風暴單體雷達特徵、雷達物理量參數縯變規律進行瞭分析。結果錶明:(1)雷達反射率因子圖上,彊風暴單體為渦鏇狀迴波,迴波前沿存在反射率因子高梯度區;速度圖上渦鏇狀迴波區對應著連續齣現中氣鏇的現象,說明彊風暴單體為具有渦鏇形態的超級單體;彊風暴頂高于11 km,大于50 dBz的彊反射率因子高度超過-20 C層的高度等特徵是產生大冰雹的重要指標。(2)風暴和中氣鏇參數分析錶明,冰雹髮生在最大反射率因子高度(HT)和風暴頂高(TOP)齣現最彊值的上升階段中,最大垂直液態水含量(VIL)為58 kg·m-2,最大反射率因子(DBZM)極值為77 dBz;VIL密度(DVIL)≥4.0 g·m-3的持續時間達1 h以上,其最大值超過6.0 g·m-3。(3)該過程大冰雹產生在最大DVIL值齣現後半小時,在DVIL為5.0 g·m-3時且在高梯度區附近齣現;大風齣現在中氣鏇持續時間較長和中氣鏇位置較高的時候。
2013년4월29일하오환서남적안경시화동지현발생료일차빙박、뇌우대풍강천기과정。본문이구강뢰체자료위주,보이GFS예보장화지면자료,중점대풍폭단체뢰체특정、뢰체물리량삼수연변규률진행료분석。결과표명:(1)뢰체반사솔인자도상,강풍폭단체위와선상회파,회파전연존재반사솔인자고제도구;속도도상와선상회파구대응착련속출현중기선적현상,설명강풍폭단체위구유와선형태적초급단체;강풍폭정고우11 km,대우50 dBz적강반사솔인자고도초과-20 C층적고도등특정시산생대빙박적중요지표。(2)풍폭화중기선삼수분석표명,빙박발생재최대반사솔인자고도(HT)화풍폭정고(TOP)출현최강치적상승계단중,최대수직액태수함량(VIL)위58 kg·m-2,최대반사솔인자(DBZM)겁치위77 dBz;VIL밀도(DVIL)≥4.0 g·m-3적지속시간체1 h이상,기최대치초과6.0 g·m-3。(3)해과정대빙박산생재최대DVIL치출현후반소시,재DVIL위5.0 g·m-3시차재고제도구부근출현;대풍출현재중기선지속시간교장화중기선위치교고적시후。
A severe storm occurred at Anqing City and Dongzhi County on 29 April 2013. The radar echo characteristics and the evolution of physical parameters of the storm cell were analysed based on Jiujiang radar data and ancillary data from GFS forecast fields and surface con-ventional observations the results are as follows.⑴Radar reflectivity indicates that the severe storm has a vortex-shaped echo. High reflectiv-ity gradient area was observed in front of the vortex-shaped echo. The fact that the vortex-shaped area in the velocity map had a continuous mesoscale cyclonic flow indicates that the severe storm was a supercell storm. The top of the severe storm was taller than 11 km, above the-20℃level height, which is considered to be an important indicator for the storm to produce large hails.⑵Based on storm and meso-cy-clone parameters, hails occurred when the height of the maximum reflectivity (HT) and the storm top height (TOP) were increased to their peak values. The maximum vertically integrated liquid water (VIL) was 58 kg·m-2, and the maximum reflectivity (DBZM) was 77 dBz. The VIL den-sity (DVIL) with value greater than 4.0 g·m-3 lasted for more than 1 hour, and its maximum reached over 6.0 g·m-3.⑶In this severe storm case, large hails occurred half hour after the maximum DVIL was observed, where DVIL had the largest gradient with a value of 5.0 g·m-3. Strong wind was found when the meso-cyclone persisted relatively long in duration and high in altitude.