scholarly journals Initiation and Development of a Squall Line Crossing Hangzhou Bay

2021 ◽  
Vol 126 (1) ◽  
Author(s):  
Lina Zhang ◽  
Juanzhen Sun ◽  
Zhuming Ying ◽  
Xian Xiao
Keyword(s):  
Squall Line ◽  
Hangzhou Bay ◽  
Line Crossing

Driving Simulation Study on Operating Speed of Hangzhou Bay Bridge

ICCTP 2010 ◽  
2010 ◽  
Author(s):  
Benmin Liu ◽  
Zhongyin Guo ◽  
Mingshan Fang
Keyword(s):  
Simulation Study ◽  
Driving Simulation ◽  
Hangzhou Bay ◽  
Operating Speed

Soil respiration dynamics in typical tidal flat wetlands of Hangzhou Bay, China

2016 ◽  
Vol 50 (2) ◽  
pp. 187-195
Author(s):  
Xuexin Shao ◽  
Wenying Yang ◽  
Wei Liang ◽  
Ming Wu
Keyword(s):  
Soil Respiration ◽  
Tidal Flat ◽  
Hangzhou Bay

Community structure of macroinvertebrates in northern Hangzhou Bay

2018 ◽  
Vol 25 (3) ◽  
pp. 663
Author(s):  
Miao WANG ◽  
Xuan ZHOU ◽  
Bo HONG
Keyword(s):  
Community Structure ◽  
Hangzhou Bay

scholarly journals Comparative analysis of dry intrusion in the different position of Pre-TC squall line on typhoon Lekima(1909) and Matsa(0509)

2021 ◽  
Author(s):  
Xiaohong Lin ◽  
Siyu Yin ◽  
Yiyong Cai ◽  
Nengzhu Fan ◽  
Chao Fu
Keyword(s):  
Comparative Analysis ◽  
Squall Line

An automatic identifying method of the squall line based on Hough transform

2021 ◽  
Author(s):  
Xing Wang ◽  
Hao-xuan Bian ◽  
Dai-li Qian ◽  
Chun-sheng Miao ◽  
Shao-wei Zhan
Keyword(s):  
Hough Transform ◽  
Squall Line

Characteristics of high-resolution subaqueous micro-topography in the Jinshan Deep Trough and its implications for riverbed deformation, Hangzhou Bay, China

2021 ◽  
Vol 250 ◽  
pp. 107147
Author(s):  
Xingjie Guo ◽  
Xuexin Yan ◽  
Shuwei Zheng ◽  
Hanmei Wang ◽  
Ping Yin
Keyword(s):  
High Resolution ◽  
Hangzhou Bay ◽  
Micro Topography

scholarly journals Analysis of the Vertical Air Motions and Raindrop Size Distribution Retrievals of a Squall Line Based on Cloud Radar Doppler Spectral Density Data

Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 348
Author(s):  
Ningkun Ma ◽  
Liping Liu ◽  
Yichen Chen ◽  
Yang Zhang
Keyword(s):  
Spectral Density ◽  
Size Distribution ◽  
Squall Line ◽  
Vertical Profiles ◽  
Air Velocity ◽  
Density Data ◽  
Cloud Radar ◽  
Raindrop Size Distribution ◽  
Raindrop Size ◽  
Reflectivity Factor

A squall line is a type of strongly organized mesoscale convective system that can cause severe weather disasters. Thus, it is crucial to explore the dynamic structure and hydrometeor distributions in squall lines. This study analyzed a squall line over Guangdong Province on 6 May 2016 that was observed using a Ka-band millimeter-wave cloud radar (CR) and an S-band dual-polarization radar (PR). Doppler spectral density data obtained by the CR were used to retrieve the vertical air motions and raindrop size distribution (DSD). The results showed the following: First, the CR detected detailed vertical profiles and their evolution before and during the squall line passage. In the convection time segment (segment B), heavy rain existed with a reflectivity factor exceeding 35 dBZ and a velocity spectrum width exceeding 1.3 m s−1. In the PR detection, the differential reflectivity factor (Zdr) was 1–2 dB, and the large specific differential phase (Kdp) also represented large liquid water content. In the transition and stratiform cloud time segments (segments B and C), the rain stabilized gradually, with decreasing cloud tops, stable precipitation, and a 0 °C layer bright band. Smaller Kdp values (less than 0.9) were distributed around the 0 °C layer, which may have been caused by the melting of ice crystal particles. Second, from the CR-retrieved vertical air velocity, before squall line passage, downdrafts dominated in local convection and weak updrafts existed in higher-altitude altostratus clouds. In segment B, the updraft air velocity reached more than 8 m s−1 below the 0 °C layer. From segments C to D, the updrafts changed gradually into weak and wide-ranging downdrafts. Third, in the comparison of DSD values retrieved at 1.5 km and DSD values on the ground, the retrieved DSD line was lower than the disdrometer, the overall magnitude of the DSD retrieved was smaller, and the difference decreased from segments C to D. The standardized intercept parameter (Nw) and shape parameter (μ) of the DSD retrieved at 1.8 km showed good agreement with the disdrometer results, and the mass-weighted mean diameter (Dm) was smaller than that on the ground, but very close to the PR-retrieved Dm result at 2 km. Therefore, comparing with the DSD retrieved at around 2 km, the overall number concentration remained unchanged and Dm got larger on the ground, possibly reflecting the process of raindrop coalescence. Lastly, the average vertical profiles of several quantities in all segments showed that, first of all, the decrease of Nw and Dm with height in segments C and D was similar, reflecting the collision effect of falling raindrops. The trends were opposite in segment B, indicating that raindrops underwent intense mixing and rapid collision and growth in this segment. Then, PR-retrieved Dm profiles can verify the rationality of the CR-retrieved Dm. Finally, a vertical velocity profile peak generated a larger Dm especially in segments C and D.

Interactions between Upper and Lower Tropospheric Gravity Waves on Squall Line Structure and Maintenance

1990 ◽  
Vol 47 (10) ◽  
pp. 1205-1222 ◽  
Author(s):  
Jerome M. Schmidt ◽  
William R. Cotton
Keyword(s):  
Gravity Waves ◽  
Squall Line ◽  
Line Structure

Tracking a Long-Lasting Outer Tropical Cyclone Rainband: Origin and Convective Transformation

2019 ◽  
Vol 76 (10) ◽  
pp. 3267-3283 ◽  
Author(s):  
Cheng-Ku Yu ◽  
Che-Yu Lin ◽  
Jhang-Shuo Luo
Keyword(s):  
Tropical Cyclone ◽  
Inner Core ◽  
Radial Distance ◽  
Vertical Shear ◽  
Convective Precipitation ◽  
Squall Line ◽  
Mature Stage ◽  
Clear Trend ◽  
Dynamical Interaction ◽  
Cold Pools

Abstract This study used radar and surface observations to track a long-lasting outer tropical cyclone rainband (TCR) of Typhoon Jangmi (2008) over a considerable period of time (~10 h) from its formative to mature stage. Detailed analyses of these unique observations indicate that the TCR was initiated on the eastern side of the typhoon at a radial distance of ~190 km as it detached from the upwind segment of a stratiform rainband located close to the inner-core boundary. The outer rainband, as it propagated cyclonically outward, underwent a prominent convective transformation from generally stratiform precipitation during the earlier period to highly organized, convective precipitation during its mature stage. The transformation was accompanied by a clear trend of surface kinematics and thermodynamics toward squall-line-like features. The observed intensification of the rainband was not simply related to the spatial variation of the ambient CAPE or potential instability; instead, the dynamical interaction between the prerainband vertical shear and cold pools, with progression toward increasingly optimal conditions over time, provides a reasonable explanation for the temporal alternation of the precipitation intensity. The increasing intensity of cold pools was suggested to play an essential role in the convective transformation for the rainband. The propagation characteristics of the studied TCR were distinctly different from those of wave disturbances frequently documented within the cores of tropical cyclones; however, they were consistent with the theoretically predicted propagation of convectively generated cold pools. The convective transformation, as documented in the present case, is anticipated to be one of the fundamental processes determining the evolving and structural nature of outer TCRs.

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