A laboratory study of graupel charging

Pereyra, Rodolfo G.; Ávila, Eldo E.; Castellano, Nesvit E.; Saunders, C. P. R.

doi:10.1029/2000jd900244

Cited by 107 publications

(109 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It has been long understood that a dominant mechanism in separation of charge in thunderstorms is rebounding ice-ice collisions occurring between particles such as graupel and pristine ice in the presence of supercooled cloud water (Reynolds et al 1957;Takahashi 1978;Jayaratne et al 1983;Pereyra et al 2000). Graupel is produced in regions where riming growth is dominant, in other words, regions of deep convection updrafts.…”

Section: B Backgroundmentioning

confidence: 99%

On Polarimetric Radar Signatures of Deep Convection for Model Evaluation: Columns of Specific Differential Phase Observed during MC3E*

Lier-Walqui

Fridlind

Ackerman

et al. 2016

Monthly Weather Review

View full text Add to dashboard Cite

The representation of deep convection in general circulation models is in part informed by cloudresolving models (CRMs) that function at higher spatial and temporal resolution; however, recent studies have shown that CRMs often fail at capturing the details of deep convection updrafts. With the goal of providing constraint on CRM simulation of deep convection updrafts, ground-based remote-sensing observations are analyzed and statistically correlated for four deep convection

show abstract

Section: B Backgroundmentioning

confidence: 99%

On Polarimetric Radar Signatures of Deep Convection for Model Evaluation: Columns of Specific Differential Phase Observed during MC3E*

Lier-Walqui

Fridlind

Ackerman

et al. 2016

Monthly Weather Review

View full text Add to dashboard Cite

show abstract

“…Electrical charging occurs mainly in the "charging zone" containing graupel/hail, ice crystals, and supercooled liquid droplets. The efficiency of charge transfer depends on the size of the ice crystals and the fall speed of the graupel pellets [Keith and Saunders, 1990;Pereyra et al, 2000;Saunders et al, 2006].…”

Section: Introductionmentioning

confidence: 99%

On the relationships between lightning frequency and thundercloud parameters of regional precipitation systems

Zipser

Liu

et al. 2010

J. Geophys. Res.

View full text Add to dashboard Cite

[1] Seasonal variations on lightning activity of precipitation systems over south China and Taiwan before and after the onset of Mei-Yu have been observed by the lightning imager sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) satellite. Lightning storms before Mei-Yu onset show higher probability of lightning, higher flash rate, and larger radar reflectivity in the mixed-phase region than the Mei-Yu regime. However, the probability of lightning occurrence with the same threshold of maximum radar reflectivity or ice scattering signature is similar for land systems before and during Mei-Yu season. Oceanic systems show slightly lower probability of lightning even with the same thresholds. Relationships between a set of TRMM-observed parameters and LIS lightning frequency are further examined. For lightning systems over land, the total area of radar echo above 35 dBZ has a closer relationship with lightning flash rate at the temperature between −5°C and −15°C than other parameters. Area of lower radar reflectivity at colder temperature, e.g., area of 20 dBZ at −40°C, is also highly correlated with lightning frequency. The highest correlation between area of specific radar reflectivity and lightning frequency is found at lower temperatures when the oceanic lightning systems are examined.

show abstract

“…Figure 1 shows the general layout of the apparatus. The experimental devices used in this work are similar to those used by Avila and Pereyra (2000), Pereyra et al (2000Pereyra et al ( , 2008, Pereyra and Avila (2002), and Bürgesser et al (2006). roplet size distribution used in the experiments.…”

Section: Methodsmentioning

confidence: 99%

“…(1991; Saunders et al (2006); Avila et al (1995Avila et al ( , 1996Avila et al ( , 1998; Pereyra et al (2000Pereyra et al ( , 2008.…”

Section: Effects On Cloud Electrificationmentioning

confidence: 99%

Measurements of electric charge separated during the formation of rime by the accretion of supercooled droplets

2010

View full text Add to dashboard Cite

Abstract.In these experiments, the electric charge carried by single particles ejected from the surface of a graupel particle growing by riming was measured. Simulated graupel pellets were grown by accretion of supercooled water drops, at temperatures ranging from −2 to −10 • C in a wind tunnel at air velocities between 5 and 10 m s −1 , with the goal of studying the charging of graupel pellets under conditions of secondary ice crystal production (Hallett-Mossop mechanism). The graupel, and induction rings upstream and downstream of the graupel, were connected to electrometers and analyzing circuits of sufficient sensitivity and speed to measure, correlate and display individual charging events. The results suggest that fewer than 1% of the ejected particles carry a measurable electric charge (>2 fC). Further, it was observed that the graupel pellets acquire a positive charge and the average charge of a single splinter ejected is −14 fC. This mechanism of ejection of charged particles seems adequate to account for a positive charge of around 1 pC that individual precipitation particles of mm-size could acquire in the lower part of the cloud, which in turn could contribute to the lower positive charge region of thunderstorms.

show abstract

A laboratory study of graupel charging

Cited by 107 publications

References 24 publications

On Polarimetric Radar Signatures of Deep Convection for Model Evaluation: Columns of Specific Differential Phase Observed during MC3E*

On Polarimetric Radar Signatures of Deep Convection for Model Evaluation: Columns of Specific Differential Phase Observed during MC3E*

On the relationships between lightning frequency and thundercloud parameters of regional precipitation systems

Measurements of electric charge separated during the formation of rime by the accretion of supercooled droplets

Contact Info

Product

Resources

About