Thunderstorm Climatologies and Their Relationships to Total and Extreme Precipitation in China

Abstract

This study investigates climatologies of lightning and thunderstorms in China and their relationships to total rainfall and extreme (hourly) precipitation (95th percentile) using spaceborne lightning, microwave, and radar measurements. Annually, total and extreme precipitation only weakly collocate or correlate with flash density (FLD) and thunderstorm. Also, none of these variables show significant trends during 1995-2014. FLD and precipitation are generally in phase on the monthly time scale, except over southern China (SCH), where FLD leads precipitation by 2 months. Thunderstorms contribute 40-50% of total rainfall and 70-80% of extreme precipitation over lower-elevation regions, but only 20% over the Tibetan Plateau. While correlation coefficients between extreme precipitation and flash rate are decent during April-May (AM, r = 0.75), they are significantly lower in June-July-August (JJA, r = 0.55), possibly due to larger warm cloud depth and thus greater rainfall contribution by warm-rain process during JJA. JJA thunderstorms have markedly higher radar echo tops (MAXHT30) and induce stronger microwave ice scattering than AM thunderstorms, related to larger convective available potential energy in JJA, whereas AM thunderstorms have larger precipitation area in association with stronger vertical wind shear. Conversely, AM thunderstorms show markedly greater number/frequency of high flash rates than JJA thunderstorms (especially over SCH), consistent with their larger volumes of intense radar echo in the mixed-phase region (VOL35). Compared to MAXHT30 (r = 0.38), VOL35 is far better correlated to flash rate (r = 0.88), as VOL35 represents the total amount of precipitation-sized ice particles and/or supercooled liquid water in the mixed-phase region essential for cloud electrification.

Convective and Microphysical Characteristics of Extreme Precipitation Revealed by Multisource Observations Over the Pearl River Delta at Monsoon Coast

“…Nevertheless, our understanding of microphysical processes leading to the generation of extreme precipitation is still far from complete. Its relationship with mixed‐phase microphysical processes (Mohr et al., 1996; Zipser & Lutz, 1994; Xu, 2020) and warm‐rain processes (Carr et al., 2017; Li, Luo, Zhang, et al., 2021; Sohn et al., 2013) is unclear.…”

Contribution of Thunderstorms to Changes in Hourly Extreme Precipitation over China from 1980 to 2011

“…Ding and Chan, 2005;Ng et al, 2021;Yuqing Wang and Zhou, 2005). Most continental extreme precipitation events are caused by severe convection accompanied by thunderstorms (Fujibe, 1988;Schumacher and Johnson, 2006;Xu, 2020;Ye et al, 2017), which are mesoscale weather phenomena. For example, thunderstorms account for 70-80% of the hourly extreme precipitation (HEP, > 95 th percentile rain rate) events over lower-elevation regions south of 38°N in China (Xu, 2020).…”

“…Most continental extreme precipitation events are caused by severe convection accompanied by thunderstorms (Fujibe, 1988;Schumacher and Johnson, 2006;Xu, 2020;Ye et al, 2017), which are mesoscale weather phenomena. For example, thunderstorms account for 70-80% of the hourly extreme precipitation (HEP, > 95 th percentile rain rate) events over lower-elevation regions south of 38°N in China (Xu, 2020). Therefore, understanding changes in thunderstorm events, and how they contribute to HEP in a warmer climate, is necessary to predict HEP behavior.…”

“…Zhang et al, 2017), leading to more frequent and intense extreme precipitation and thunderstorms (Ma et al, 2017;Sun et al, 2007;Xu, 2013). According to Xu (2020), stronger vertical wind shear (VWS), and a larger convective available potential energy (CAPE), are conducive to thunderstorm development. CAPE and VWS have been considered together in analyses of severe thunderstorms in the United States and Europe (Taszarek et al, 2021).…”

“…Instability/updraft speed can be controlled by CAPE, which exerts a buoyancy force on rising air parcels (Diffenbaugh et al, 2013;Taszarek et al, 2021;Xu, 2020). CAPE can be calculated by various methods, including lifting the parcel from various levels.…”