Extreme large-scale atmospheric circulation associated with the “21·7” Henan flood

Xu, Jun; Li, Rumeng; Zhang, Qinghong; Chen, Yun; Liang, Xudong; Gu, Xiujie

doi:10.1007/s11430-022-9975-0

Cited by 18 publications

(12 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results suggest relatively weak updrafts as well as hail growth above the freezing level in Zhengzhou event (Kumjian et al, 2014;Tam et al, 2022), collaborating with previous studies that the extreme rainfall is more favorable in shallower convection (J. Xu et al, 2022;Yu et al, 2022).…”

Section: Z Dr Backwards Arc Signaturessupporting

confidence: 89%

“…The intersected Z DR columns , which are indicative of updrafts, were located at about 50° and 200°, despite that the Z DR values above 0°C level are significantly lower than those in deep convections (Kumjian et al., 2014). The results suggest relatively weak updrafts as well as hail growth above the freezing level in Zhengzhou event (Kumjian et al., 2014; Tam et al., 2022), collaborating with previous studies that the extreme rainfall is more favorable in shallower convection (J. Xu et al., 2022; Yu et al., 2022).…”

Section: Radar Polarimetric Observationssupporting

confidence: 88%

“…On 20 July 2021, an unprecedented rainfall storm pouring record-breaking hourly rainfall of 201.9 mm hit urban Zhengzhou and caused tremendous losses. This event took place under favorable synoptic conditions (Sun, Fu, et al, 2023;J. Xu et al, 2022;S.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Li,

Yin,

Kumjian

2024

Geophysical Research Letters

View full text Add to dashboard Cite

In this study, we present radar polarimetric characterizations of the storm producing 201.9 mm hourly rainfall on 20 July 2021 in Zhengzhou, China. We employed the separation signatures of enhanced polarimetric observations to investigate hydrometeor size sorting processes, and developed an algorithm to quantify the size sorting directions. Analysis of coupled polarimetric observations unraveled multi‐directional size sorting (MSS) occurred as a low‐level differential reflectivity ZDR backwards arc signature encompassing the rainfall center during the most intensive rainfall period. The rainfall intensification is in step with the increase of size sorting directions. Model simulations with two‐moment microphysics scheme suggest that the presence of arc‐shaped updrafts is conducive to MSS and increased rain rates around the rainfall center. This work sheds novel insights into the kinematics‐driven microphysics in extreme rainfall storms, warranting the potential of using coupled polarimetric signatures for warning catastrophic extreme rainfall events.

show abstract

Section: Z Dr Backwards Arc Signaturessupporting

confidence: 89%

Section: Radar Polarimetric Observationssupporting

confidence: 88%

See 1 more Smart Citation

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Li,

Yin,

Kumjian

2024

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…This study focuses on the circulation background, influencing systems, physical quantity fields of extreme precipitation weather processes, and the backward trajectory characteristics of air parcels during precipitation events [26][27][28][29]. Different levels of extreme precipitation events are categorized into various types based on large-scale circulation patterns [30][31][32]. This research explores the connection between extreme precipitation events, atmospheric rivers (ARs), and moisture contribution [33][34][35][36][37], using a moisture trajectory model to identify the primary moisture source of precipitation.…”

Section: Introductionmentioning

confidence: 99%

Spatiotemporal Variation and Causes of Typical Extreme Precipitation Events in Shandong Province over the Last 50 Years

Liu,

Li,

2024

Remote Sensing

View full text Add to dashboard Cite

In this study, based on hourly ERA5 reanalysis data from July to September, from 1971 to 2020, for Shandong Province, we used mathematical statistical analysis, the Mann–Kendall nonparametric statistical test, cluster analysis, and other methods to extract and analyze the spatiotemporal variation characteristics and causes of typical extreme precipitation events. The results indicated the following: (1) The total number and duration of precipitation events show a nonsignificant upward trend, while the average and extreme rainfall intensities show a nonsignificant downward trend. (2) Extreme precipitation events are primarily concentrated in Qingdao, Jinan, Heze, and Binzhou, with fewer events occurring in central Shandong Province. (3) Extreme precipitation events are classified into four types (namely, patterns I, II, III, and IV). Pattern I exhibits two rain peaks, with the primary rain peak occurring after the secondary rain peak. Similarly, pattern II also displays two rain peaks, with equivalent rainfall amounts for both peaks. In contrast, pattern III has multiple, evenly distributed rain peaks. Finally, pattern IV shows a rain peak during the first half of the precipitation event. Pattern I has the highest occurrence probability (46%), while pattern IV has the lowest (7%). (4) The spatial distributions of the different rain patterns are similar, with most being found in the eastern coastal and western regions. (5) Extreme precipitation events result from interactions between large-scale circulation configurations and mesoscale convective systems. The strong blocking situation and significant circulation transport at middle and low latitudes in East Asia, along with strong convergent uplift, abnormally high specific humidity, and high-water-vapor convergence centers, play crucial roles in supporting large-scale circulation systems and triggering mesoscale convective systems.

show abstract

“…Analyses suggest that the enhanced East Asian summer monsoon (EASM) in July provided a favorable circulation background for this rainfall extreme. It featured the northward displacement of the western North Pacific subtropical high (WNPSH) with rich moisture transmission to most areas in North China (Zhao et al., 2019; S. H. Huang et al., 2022; Ma et al., 2022; J. Xu et al., 2022). More importantly, two simultaneous tropical cyclones (TCs) of IN‐FA and CEMPAKA generated in the western North Pacific (WNP) and the South China Sea during the heavy rainfall event.…”

Section: Introductionmentioning

confidence: 99%

Subseasonal Predictability of the July 2021 Extreme Rainfall Event Over Henan China in S2S Operational Models

2023

View full text Add to dashboard Cite

Early warning and accurate forecasting of weather and climate extremes are critical to avoid natural disasters that damage human lives, especially in megacities. Heavy rainfall can engender widespread flooding, landslides or mudslides, and urban waterlogging, causing substantial economic losses and casualties (Blöschl et al., 2017;Field et al., 2012;Gariano & Guzzetti, 2016). The warning of extreme rainfall is largely determined by the effective leading time of dynamical forecasting systems. While numerical weather prediction (NWP) is an indispensable tool for handling extreme rainfall events, forecasting on the subseasonal-to-seasonal (S2S) time scale (10-90 days) may add the value of advance warning to better preparedness and emergency measures (Merz et al., 2020;White et al., 2022).The S2S prediction project releases operational forecasts and reforecasts, with particular emphasis on high-impact weather events (Vitart et al., 2017), which provide a valuable tool for risk management and communication with

show abstract

Extreme large-scale atmospheric circulation associated with the “21·7” Henan flood

Cited by 18 publications

References 35 publications

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Spatiotemporal Variation and Causes of Typical Extreme Precipitation Events in Shandong Province over the Last 50 Years

Subseasonal Predictability of the July 2021 Extreme Rainfall Event Over Henan China in S2S Operational Models

Contact Info

Product

Resources

About

Extreme large-scale atmospheric circulation associated with the “21·7” Henan flood

Cited by 18 publications

References 35 publications

ZDR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

ZDR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Spatiotemporal Variation and Causes of Typical Extreme Precipitation Events in Shandong Province over the Last 50 Years

Subseasonal Predictability of the July 2021 Extreme Rainfall Event Over Henan China in S2S Operational Models

Contact Info

Product

Resources

About

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall

Z_DR Backwards Arc: Evidence of Multi‐Directional Size Sorting in the Storm Producing 201.9 mm Hourly Rainfall