doi:10.1007/s00376-015-4170-3

Barthe C., W. Deierling, and M. C. Barth, 2010: Estimation of total lightning from various storm parameters: A cloud-resolving model study. J. Geophys. Res., 115,D24202, doi: 10.1029/2010JD014405.10.1029/2010JD014405

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2010JD014405%2Fcitedby

refpaperuri:(c4140f698c726a9d09d99bee94242495)

http://onlinelibrary.wiley.com/doi/10.1029/2010JD014405/citedby[1] Because explicit prediction of the electrical activity in storms is computationally expensive and the processes are still poorly understood, an attractive way to predict lightning flash rates in numerical models is to rely on correlations between the flash rate and available model parameters. Predicted flash rates can be used for applications such as the parameterization to infer lightning-produced nitrogen oxides. In this study, the potential for six model parameters (precipitation ice mass, ice water path, ice mass flux product, updraft volume, maximum vertical velocity, and cloud top height) to predict lightning rate has been investigated in a cloud-resolving model framework. The Weather Research and Forecasting model (WRF) is used to simulate two different storms: the 10 July 1996 severe storm that occurred over the High Plains and the 13 July 2005 airmass thunderstorm near Huntsville, Alabama. It is shown that the WRF model reproduces the structure of the two storms. Results show that the maximum updraft velocity gives a good flash rate proxy for the severe storm. The ice mass flux product and precipitation ice mass can reproduce the flash rate trend but not the magnitude. The flash rate estimated from the cloud top height does not match the observed flash rate trend and value of the severe storm, but is in good agreement for the airmass thunderstorm. The ice water path predicts flash rate fairly well for the severe storm, but overpredicts it for the airmass thunderstorm. The updraft volume predicts flash rate poorly for both storms.

Blyth A. M., H. J. Christian Jr., K. Driscoll, A. M. Gadian, and J. Latham, 2001: Determination of ice precipitation rates and thunderstorm anvil ice contents from satellite observations of lightning. Atmospheric Research,59-60, 217- 229.10.1016/S0169-8095(01)00117-X

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS016980950100117X

refpaperuri:(4cb90d9db05535f4fa63456d77368da5)

http://www.sciencedirect.com/science/article/pii/S016980950100117XThe continuous satisfactory functioning of satellite-borne devices for the detection of global lightning offers the opportunity to explore relationships between lightning frequencyand other thundercloud parameters, notably, in this paper, the precipitating and non-precipitating contents and fluxes of ice.Simple calculations predict that the lightning frequency f is proportional to the product of the downward flux of solid precipitation through the body of the thundercloud and the upward flux of ice crystals into its anvil. This prediction is reinforced by computations performed using the multiple lightning model of Baker et al. [Q. J. R. Meteorol. Soc. 121 (1995) 1525; Atmos. Res. 51 (1999) 221].Calculations indicate that the separation of charge and associated field development in thunderclouds are not significantly limited by charge saturation of the interacting hydrometeors: and that the mutual interactions of graupel pellets in the charging zones of thunderstorms can significantly enhance electric field development, culminating in lightning.An examination of data from the satellite-borne Lightning Imaging Sensor (LIS) and TRMM Microwave Imager (TMI) suggests that thunderstorms with the highest frequency of total lightning also possess the most pronounced microwave scattering signatures at 37 and 85 GHz. A total of 292 individual thunderstorms were examined, and a log-linear relationship was shown to exist (one for each frequency) between the number of optical lightning pulses produced by each storm and the corresponding microwave brightness temperatures. These relationships are consistent throughout the seasons in a variety of regimes (12 sites encompassing five continents, as well as oceanic measurements), suggesting that global relationships may be found to exist between lightning activity and cloud ice content.

Carey L. D., M. J. Murphy, T. L. McCormick, and N. W. S. Demetriades, 2005: Lightning location relative to storm structure in a leading-line, trailing-stratiform mesoscale convective system. J. Geophys. Res., 110,D03105, doi: 10.1029/2003JD 004371.10.1029/2003JD004371

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2003JD004371%2Fcitedby

refpaperuri:(d3cfee58ceed616de631c3ca288fd069)

http://onlinelibrary.wiley.com/doi/10.1029/2003JD004371/citedby[1] Horizontal and line-normal, vertical cross-sections and composite images of Dallas-Fort Worth Lightning Detection and Ranging (LDAR II) VHF radiation sources and radar reflectivity over a 30-min period provide a unique perspective on lightning pathways within a leading-line, trailing-stratiform (LLTS) mesoscale convective system (MCS) on 16 June 2002. The overwhelming majority of VHF lightning sources occurred within the leading convective line in a bimodal pattern in the vertical. Assuming that VHF source density maxima were most likely associated with positive charge, then the LDAR II observations suggest that the gross charge structure of the convective region of the MCS was characterized by a tripole with net positive charge centered at 4.5 km AGL (3°C) and 9.5 km AGL (6135°C) and net negative charge centered roughly in the relative minimum of the VHF source density maximum at 7 km AGL (6117°C). A persistent lightning pathway and inferred positive charge zone sloped rearward (by 40–50 km) and downward (by 4–5 km) from the upper VHF source maximum in the convective line, through the transition zone, and into the radar bright band of the stratiform region. In the stratiform region, VHF lightning sources and inferred positive charge were concentrated in three layers centered at 4.5, 6, and 9 km AGL (2°C, 6111°C, and 6131°C, respectively), consistent with past electric field studies of symmetric LLTS MCSs. Positive cloud-to-ground lightning flashes in the stratiform region were initiated in the convective line and followed the slanting pathway from the top of convective cores to the stratiform precipitation, where they were horizontally extensive, layered, and highly branched. The sloping lightning pathway was identical to hypothetical trajectories taken by snow particles. These observations provide further support for the advection of charge on snow along the sloping pathway and the in situ generation of charge in the horizontal lightning layers as primary contributors to electrification and positive lightning production rearward of the convective line.

Carey L. D., S. A. Rutledge, and W. A. Peterson, 2003: Evolution of cloud-to-ground lightning and storm structure in the Spencer, South Dakota, tornadic supercell of 30 May 1998. Mon. Wea. Rev., 131, 1811- 1831.10.1175//2566.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F255580771_Evolution_of_Cloud-to-Ground_Lightning_and_Storm_Structure_in_the_Spencer_South_Dakota_Tornadic_Supercell_of_30_May_1998

refpaperuri:(444c18f62313ddf98ca7de6012a313a1)

http://www.researchgate.net/publication/255580771_Evolution_of_Cloud-to-Ground_Lightning_and_Storm_Structure_in_the_Spencer_South_Dakota_Tornadic_Supercell_of_30_May_1998On 30 May 1998, a tornado devastated the town of Spencer, South Dakota. The Spencer tornado (rated F4 on the Fujita tornado intensity scale) was the third and most intense of five tornadoes produced by a single supercell storm during an approximate 1-h period. The supercell produced over 76% positive cloud-to-ground (CG) lightning and a peak positive CG flash rate of 18 flashes min[sup -1] (5-min average) during a 2-h period surrounding the tornado damage. Earlier studies have reported anomalous positive CG lightning activity in some supercell storms producing violent tornadoes. However, what makes the CG lightning activity in this tornadic storm unique is the magnitude and timing of the positive ground flashes relative to the F4 tornado. In previous studies, supercells dominated by positive CG lightning produced their most violent tornado after they attained their maximum positive ground flash rate, whenever the rate exceeded 1.5 flashes min[sup -1] . Further, tornadogenesis often occurred during a lull in CG lightning activity and sometimes during a reversal from positive to negative polarity. Contrary to these findings, the positive CG lightning flash rate and percentage of positive CG lightning in the Spencer supercell increased dramatically while the storm was producing F4 damage on Spencer. These results have important implications for the use of CG lightning in the nowcasting of tornadoes and for the understanding of cloud electrification in these unique storms. In order to further explore these issues, the authors present detailed analyses of storm evolution and structure using Sioux Falls, South Dakota, (KFSD) Weather Surveillance Radar-1988 Doppler (WSR-88D) radar reflectivity and Doppler velocity and National Lightning Detection Network (NLDN) CG lightning data. The analyses suggest that a merger between the Spencer supercell and a squall line on its rear flank may have provided the impetus for both the F4 tornadic damage and the dramatic increase in positive CG lightning during the tornado, possibly explaining the difference in timing compared to past studies.

Chong M., P. Amayenc, G. Scialom, and J. Testud, 1987: A tropical squall line observed during the COPT 81 experiment in West Africa. Part 1: Kinematic structure inferred from dual-Doppler radar data. Mon. Wea. Rev., 115, 670- 694.10.1175/1520-0493(1987)1152.0.CO;2

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fresolve%2Freference%2FADS%3Fid%3D1987MWRv..115..670C

refpaperuri:(69299189be786b2ccbf74c975ab71081)

http://onlinelibrary.wiley.com/resolve/reference/ADS?id=1987MWRv..115..670CAbstract This paper deals with the analysis of a tropical squall line, observed on 22 June 1981 during the COPT 81 (Convection Profonde Tropicale) experiment. The present Part I is restricted to the study of the kinematic structure of the system, which moved in a moderately unstable atmosphere, faster than the environmental air at all levels. At the observation time, the squall line was in a mature stage. The explicit description of the airflow within the system was inferred from dual- and single-Doppler radar data. The general characteristics of the squall line are found to be very similar to those of tropical squall lines observed during previous experiments such as VHIMEX or GATE: a large cloud system composed of an organized convective line ahead of an extensive trailing anvil cloud (stratiform rain), fast motion and long-lasting structure and a well-marked gust front signature at ground level. The overall airflow presents a three-dimensional structure. At the leading edge, convective-scale updrafts a...

Deierling W., W. A. Petersen, J. Latham, S. Ellis, and H. J. Christian, 2008: The relationship between lightning activity and ice fluxes in thunderstorms. J. Geophys. Res., 113,D15210, doi: 10.1029/2007JD009700.10.1029/2007JD009700

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2007JD009700%2Fpdf

refpaperuri:(d34a985bc5c52cae8072f2d8f6dba565)

http://onlinelibrary.wiley.com/doi/10.1029/2007JD009700/pdf[1] It is generally believed that a strong updraft in the mixed-phase region of thunderstorms is required to produce lightning. This is the region where the noninductive charging process is thought to generate most of the storm electrification. Analytic calculations and model results predict that the total lightning frequency is roughly proportional to the product of the downward mass flux of solid precipitation (graupel) and the upward mass flux of ice crystals. Thus far this flux hypothesis has only been tested in a very limited way. Herein we use dual-polarimetric and dual-Doppler radar observations in conjunction with total lightning data collected in Northern Alabama and also Colorado/Kansas during two field campaigns. These data are utilized to investigate total lightning activity as a function of precipitation and nonprecipitation ice masses and estimates of their fluxes for different storm types in different climate regions. A total of 11 storms, including single cell, multicell, and supercell storms, was analyzed in the two climatologically different regions. Time series of both precipitation and nonprecipitation ice mass estimates above the melting level show a good relationship with total lightning activity for the 11 storms analyzed (correlation coefficients exceed 0.9 and 0.8, respectively). Furthermore, the relationships are relatively invariant between the two climate regions. The correlations between total lightning and the associated product of ice mass fluxes are even higher. These observations provide strong support for the flux hypothesis.

Ely B. L., R. E. Orville, L. D. Carey, and C. L. Hodapp, 2008: Evolution of the total lightning structure in a leading-line, trailing-stratiform mesoscale convective system over Houston, Texas . J. Geophys. Res., 113,D08114, doi: 10.1029/ 2007JD008445.10.1029/2007JD008445

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http://onlinelibrary.wiley.com/doi/10.1029/2007JD008445/full

http://onlinelibrary.wiley.com/doi/10.1029/2007JD008445/full[1] Line-normal, vertical cross sections of Houston Lightning Detection and Ranging (LDAR) VHF radiation sources and radar reflectivity provide new insights into the three-dimensional total lightning structure and evolution of a leading-line, trailing-stratiform (LLTS) mesoscale convective system (MCS) over Houston, Texas, on 31 October 2005. Previous research examining only the mature stage of an MCS showed that the overwhelming majority of VHF lightning sources occurred in the convective region with a lightning pathway extending rearward and descending in altitude into the stratiform region. This descending pathway was most likely associated with small, charged ice particles advected from the convective line. Unlike previous research, the lightning pathway observed during the evolution of the MCS on 31 October 2005 initially extended rearward 40 km at a nearly constant height of 9-10 km. In less than an hour, the lightning pathway evolved into a sloped pathway, similar to that found by previous research, with a horizontal extent between 50 to 60 km and downward descent of 4 to 5 km. During the lightning pathway evolution, radar analysis showed an increase of reflectivity in the midlevels of the stratiform region, consistent with increased depositional and aggregational growth above the melting layer. Broadening (increased range of values) of radar reflectivity above the melting layer was most likely an indication of a strengthening mesoscale updraft in the stratiform region. This strengthening updraft may have contributed to an increase in the growth of the small, charge carrying ice crystals giving them a greater fall speed. In addition, the mesoscale updraft may have promoted an environment conducive to local stratiform region charge generation in the mixed phase region just above the melting layer.

Feng G. L., X. S. Qie, J. Wang, and D. L. Gong, 2009: Lightning and Doppler radar observations of a squall line system. Atmospheric Research, 91, 466- 478.10.1016/j.atmosres.2008.05.015

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0169809508002202

refpaperuri:(65f841ddfa7e3f5cfbe3735cf8e05533)

http://www.sciencedirect.com/science/article/pii/S0169809508002202ABSTRACT A typical squall line with damaging wind and hailstones occurred on 28 April 2006 in Shandong Province, middle eastern China, and caused great economic loss. The characteristics of cloud-to-ground lightning (CG) in the squall line were studied in detail by combining the data from the ground-based CG location network, two Doppler radars and the Lightning Imaging Sensor on the TRMM satellite. Results show that positive CG flashes accounted for 54.7% of the total CG flashes. During the initial developing stage, the CG flash rate was lower than 0.5fl min 1 and most of the CG flashes were positive. It increased significantly, up to 4.5fl min 1, along with the rapid development of the squall line, and the percentage of positive CG was more than 75% during this period. The CG flash rate began to decrease but the percentage of negative CG flash increased gradually and exceeded that of positive CG during the mature and dissipating stages. Positive CG flashes tended to occur on the right flank and negative ones on the left flank. Strong wind at the surface occurred in or near the regions with dense positive CG flashes. Almost all positive CG flashes occurred near the strong radar echo regions, in the front parts of the squall line. However, the negative CG flashes almost exclusively occurred in the regions with weak and uniform radar echoes. The total flash rate in the storm was very high, up to 136fl min1, and its ratio of intracloud flashes (IC) to CG flashes was 35:1. Dense positive CG flashes corresponded to updraft regions, they did not occur in the core of the updraft, but just behind and close to the main updraft instead. The rear inflow jet, between 3 and 6 km, played an important role in the formation of the bow echo and very strong wind at surface. The CG distribution features in the squall line were obviously different from that of an ordinary MCS. The charge structure could be roughly described as an inverted charge structure.

Hong S.-Y., J.-O. J. Lim, 2006: The WRF single-moment 6-class microphysics scheme (WSM6). Journal of the Korean Meteorological Society, 42( 3), 129- 151.dbe7d217-fe4f-44d9-a2a0-0409c5d495e5

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http%3A%2F%2Fwww.dbpia.co.kr%2FJournal%2FArticleDetail%2F773025

refpaperuri:(6e4d91088728a0340628b3f4166a8af2)

http://www.dbpia.co.kr/Journal/ArticleDetail/773025This study examines the performance of the Weather Research and Forecasting (WRF)-Single-Moment- Microphysics scheme (WSMMPs) with a revised ice-microphysics of the Hong et al. In addition to the simple (WRF Single-Moment 3-class Microphysics scheme; WSM3) and mixed-phase (WRF Single-Moment 5-class Microphysics scheme; WSM5) schemes of the Hong et al., a more complex scheme with the inclusion of graupel as another predictive variable (WRF Single-Moment 6-class Microphysics scheme; WSM6) was developed. The characteristics of the three categories of WSMMPs were examined for an idealized storm case and a heavy rainfall event over Korea. In an idealized thunderstorm simulation, the overall evolutionary features of the storm are not sensitive to the number of hydrometeors in the WSMMPs; however, the evolution of surface precipitation is significantly influenced by the complexity in microphysics. A simulation experiment for a heavy rainfall event indicated that the evolution of the simulated precipitation with the inclusion of graupel (WSM6) is similar to that from the simple (WSM3) and mixed-phase (WSM5) microphysics in a low-resolution grid; however, in a high-resolution grid, the amount of rainfall increases and the peak intensity becomes stronger as the number of hydrometeors increases.

Hong S. Y., Y. Noh, and J. Dudhia, 2006: A new vertical diffusion package with an explicit treatment of entrainment processes. Mon. Wea. Rev., 134, 2318- 2341.10.1175/MWR3199.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F252170327_A_New_Vertical_Diffusion_Package_with_an_Explicit_Treatment_of_Entrainment_Processes

refpaperuri:(fd0cba578920821c17be8d8e91464f15)

http://www.researchgate.net/publication/252170327_A_New_Vertical_Diffusion_Package_with_an_Explicit_Treatment_of_Entrainment_ProcessesAbstract This paper proposes a revised vertical diffusion package with a nonlocal turbulent mixing coefficient in the planetary boundary layer (PBL). Based on the study of Noh et al. and accumulated results of the behavior of the Hong and Pan algorithm, a revised vertical diffusion algorithm that is suitable for weather forecasting and climate prediction models is developed. The major ingredient of the revision is the inclusion of an explicit treatment of entrainment processes at the top of the PBL. The new diffusion package is called the Yonsei University PBL (YSU PBL). In a one-dimensional offline test framework, the revised scheme is found to improve several features compared with the Hong and Pan implementation. The YSU PBL increases boundary layer mixing in the thermally induced free convection regime and decreases it in the mechanically induced forced convection regime, which alleviates the well-known problems in the Medium-Range Forecast (MRF) PBL. Excessive mixing in the mixed layer in the presence of strong winds is resolved. Overly rapid growth of the PBL in the case of the Hong and Pan is also rectified. The scheme has been successfully implemented in the Weather Research and Forecast model producing a more realistic structure of the PBL and its development. In a case study of a frontal tornado outbreak, it is found that some systematic biases of the large-scale features such as an afternoon cold bias at 850 hPa in the MRF PBL are resolved. Consequently, the new scheme does a better job in reproducing the convective inhibition. Because the convective inhibition is accurately predicted, widespread light precipitation ahead of a front, in the case of the MRF PBL, is reduced. In the frontal region, the YSU PBL scheme improves some characteristics, such as a double line of intense convection. This is because the boundary layer from the YSU PBL scheme remains less diluted by entrainment leaving more fuel for severe convection when the front triggers it.

Hu M., M. Xue, and K. Brewster, 2006a: 3DVAR and cloud analysis with WSR-88D Level-II data for the prediction of the fort worth, Texas, Tornadic Thunderstorms. Part I: Cloud analysis and its impact. Mon. Wea. Rev., 134, 675- 698.10.1175/MWR3092.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F242369318_3DVAR_and_Cloud_Analysis_with_WSR-88D_Level-II_Data_for_the_Prediction_of_the_Fort_Worth_Texas_Tornadic_Thunderstorms._Part_I_Cloud_Analysis_and_Its_Impact

refpaperuri:(2a1b9c7a13ebb23ea77ced12a2fbf3d1)

http://www.researchgate.net/publication/242369318_3DVAR_and_Cloud_Analysis_with_WSR-88D_Level-II_Data_for_the_Prediction_of_the_Fort_Worth_Texas_Tornadic_Thunderstorms._Part_I_Cloud_Analysis_and_Its_ImpactIn this two-part paper, the impact of level-II Weather Surveillance Radar-1988 Doppler (WSR-88D) reflectivity and radial velocity data on the prediction of a cluster of tornadic thunderstorms in the Advanced Regional Prediction System (ARPS) model are studied. Radar reflectivity data are used primarily in a cloud analysis procedure that retrieves the amount of hydrometeors and adjusts in-cloud temperature, moisture, and cloud fields, while radial velocity data are analyzed through a three-dimensional variational (3DVAR) scheme that contains a mass divergence constraint in the cost function. In Part I, the impact of the cloud analysis and modifications to the scheme are examined while Part II focuses on the impact of radial velocity and the mass divergence constraint. The case studied is that of the 28 March 2000 Fort Worth, Texas, tornado outbreaks. The same case was studied by Xue et al. using the ARPS Data Analysis System (ADAS) and an earlier version of the cloud analysis procedure with WSR-88D level-III data. Since then, several modifications to the cloud analysis procedure, including those to the in-cloud temperature adjustment and the analysis of precipitation species, have been made. They are described in detail with examples. The assimilation and predictions use a 3-km grid nested inside a 9-km one. The level-II reflectivity data are assimilated, through the cloud analysis, at 10-min intervals in a 1-h period that ends a little over 1 h preceding the first tornado outbreak. Experiments with different settings within the cloud analysis procedure are examined. It is found that the experiment using the improved cloud analysis procedure with reflectivity data can capture the important characteristics of the main tornadic thunderstorm more accurately than the experiment using the early version of cloud analysis. The contributions of different modifications to the above improvements are investigated.

Hu M., M. Xue, J. D. Gao, and K. Brewster, 2006b: 3DVAR and cloud analysis with WSR-88D Level-II data for the prediction of the fort worth, Texas, Tornadic Thunderstorms. Part II: Impact of radial velocity analysis via 3DVAR. Mon. Wea. Rev., 134, 699- 721.10.1175/MWR3093.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F237224897_3DVAR_and_cloud_analysis_with_WSR-88D_level-II_data_for_the_prediction_of_Fort_Worth_tornadic_thunderstorms._Part_II_Impact_of_radial_velocity_analysis_via_3DVAR

refpaperuri:(d3aa07fe46728396cb8e318184d5e05c)

http://www.researchgate.net/publication/237224897_3DVAR_and_cloud_analysis_with_WSR-88D_level-II_data_for_the_prediction_of_Fort_Worth_tornadic_thunderstorms._Part_II_Impact_of_radial_velocity_analysis_via_3DVARAbstract In this two-part paper, the impact of level-II Weather Surveillance Radar-1988 Doppler (WSR-88D) radar reflectivity and radial velocity data on the prediction of a cluster of tornadic thunderstorms in the Advanced Regional Prediction System (ARPS) model is studied. Radar reflectivity data are used primarily in a cloud analysis procedure that retrieves the amount of hydrometeors and adjusts in-cloud temperature, moisture, and cloud fields, while radial velocity data are analyzed through a three-dimensional variational (3DVAR) data assimilation scheme that contains a 3D mass divergence constraint in the cost function. In Part I, the impact of the cloud analysis and modifications to the scheme are discussed. In this part, the impact of radial velocity data and the mass divergence constraint in the 3DVAR cost function are studied. The case studied is that of the 28 March 2000 Fort Worth tornadoes. The addition of the radial velocity improves the forecasts beyond that experienced with the cloud analysis alone. The prediction is able to forecast the morphology of individual storm cells on the 3-km grid up to 2 h; the rotating supercell characteristics of the storm that spawned two tornadoes are well captured; timing errors in the forecast are less than 15 min and location errors are less than 10 km at the time of the tornadoes. When forecasts were made with radial velocity assimilation but not reflectivity, they failed to predict nearly all storm cells. Using the current 3DVAR and cloud analysis procedure with 10-min intermittent assimilation cycles, reflectivity data are found to have a greater positive impact than radial velocity. The use of radial velocity does improve the storm forecast when combined with reflectivity assimilation, by, for example, improving the forecasting of the strong low-level vorticity centers associated with the tornadoes. Positive effects of including a mass divergence constraint in the 3DVAR cost function are also documented.

Keighton S. J., H. B. Bluestein, and D. R. MacGorman, 1991: The evolution of a severe mesoscale convective system: Cloud-to-ground lightning location and storm structure. Mon. Wea. Rev., 119, 1533- 1556.10.1175/1520-0493(1991)1192.0.CO;2

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F249620643_The_Evolution_of_a_Severe_Mesoscale_Convective_System_Cloud-to-Ground_Lightning_Location_and_Storm_Structure

refpaperuri:(b0f9dbb198e360cd890552aa799945a6)

http://www.researchgate.net/publication/249620643_The_Evolution_of_a_Severe_Mesoscale_Convective_System_Cloud-to-Ground_Lightning_Location_and_Storm_StructureAbstract Cloud-to-ground lightning-location data are correlated with the Doppler-radar-observed structure of the evolution of a severe mesoscale convective system in Oklahoma on 23 May 1981. While many of the results are not new, this study is unique in that the evolution of electrical activity in a severe storm is compared to storm structure for most of the storm's life. The, first storm formed ahead of a mesoscale low pressure area located at the intersection of a front and a dryline, and developed into a tornadic supercell in an environment of locally enhanced vertical shear. Ordinary cells subsequently formed both to the southwest and northeast of the supercell along the dryline and the front, respectively, and merged with the supercell to form a squall line having a trailing stratiform precipitation region with midlevel rear inflow. It is shown that the cloud-to-ground flash rate in the convective region is related to the apparent strength of the updraft. Before the storm became a supercell, the lightning strikes, which were relatively infrequent, emanated from the anvil west of the core. When the supercell was producing its first tornado, most lightning strikes occurred around the edge of the most intense core and under the anvil south of the core. As the supercell weakened, ground strikes clustered closer to the core. During the squall-line stage, most cloud-to-ground lightning strikes were found to the rear of the core of the remnants of the supercell, and in the core of the cells to the southwest, which were less mature. The overall ground-strike rate peaked during the middle portion of the squall-line phase. The area of the midlevel radar echo associated with the most intense reflectivity core was well correlated with the ground strike rate. The area of midlevel radar echo representing the weaker portion of the core, however, lagged the ground-strike rate.

Kuhlman K. M., C. L. Ziegler, E. R. Mansell, D. R. MacGorman, and J. M. Straka, 2006: Numerically simulated electrification and lightning of the 29 June 2000 STEPS supercell storm. Mon. Wea. Rev., 134, 2734- 2757.10.1175/MWR3217.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F253476365_Numerically_Simulated_Electrification_and_Lightning_of_the_29_June_2000_STEPS_Supercell_Storm

refpaperuri:(66ff184cd5d84879ffe2bab76ba13dfc)

http://www.researchgate.net/publication/253476365_Numerically_Simulated_Electrification_and_Lightning_of_the_29_June_2000_STEPS_Supercell_StormAbstract A three-dimensional dynamic cloud model incorporating airflow dynamics, microphysics, and thunderstorm electrification mechanisms is used to simulate the first 3 h of the 29 June 2000 supercell from the Severe Thunderstorm Electrification and Precipitation Study (STEPS). The 29 June storm produced large flash rates, predominately positive cloud-to-ground lightning, large hail, and an F1 tornado. Four different simulations of the storm are made, each one using a different noninductive (NI) charging parameterization. The charge structure, and thus lightning polarity, of the simulated storm is sensitive to the treatment of cloud water dependence in the different NI charging schemes. The results from the simulations are compared with observations from STEPS, including balloon-borne electric field meter soundings and flash locations from the Lightning Mapping Array. For two of the parameterizations, the observed nverted tripolar charge structure is well approximated by the model. The polarity of the ground flashes is opposite that of the lowest charge region of the inverted tripole in both the observed storm and the simulations. Total flash rate is well correlated with graupel volume, updraft volume, and updraft mass flux. However, there is little correlation between total flash rate and maximum updraft speed. Based on the correlations found in both the observed and simulated storm, the total flash rate appears to be most representative of overall storm intensity.

Lang T.J., Coauthors, 2004a: The severe thunderstorm electrification and precipitation study. Bull. Amer. Meteor. Soc., 85, 1107- 1125.10.1175/BAMS-85-8-1107

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1d9a45d9337bf4c953cfc8b36bef1286

http://www.researchgate.net/publication/237245927_The_Severe_Thunderstorm_Electrification_and_Precipitation_Study?ev=auth_pub

http://www.researchgate.net/publication/237245927_The_Severe_Thunderstorm_Electrification_and_Precipitation_Study?ev=auth_pubAbstract During Mayuly 2000, the Severe Thunderstorm Electrification and Precipitation Study (STEPS) occurred in the High Plains, near the Coloradoansas border. STEPS aimed to achieve a better understanding of the interactions between kinematics, precipitation, and electrification in severe thunderstorms. Specific scientific objectives included 1) understanding the apparent major differences in precipitation output from super-cells that have led to them being classified as low precipitation (LP), classic or medium precipitation, and high precipitation; 2) understanding lightning formation and behavior in storms, and how lightning differs among storm types, particularly to better understand the mechanisms by which storms produce predominantly positive cloud-to-ground (CG) lightning; and 3) verifying and improving microphysical interpretations from polarimetric radar. The project involved the use of a multiple-Doppler polarimetric radar network, as well as a time-of-arrival very high frequency (VHF) lightning mapping system, an armored research aircraft, electric field meters carried on balloons, mobile mesonet vehicles, instruments to detect and classify transient luminous events (TLEs; e.g., sprites and blue jets) over thunderstorms, and mobile atmospheric sounding equipment. The project featured significant collaboration with the local National Weather Service office in Goodland, Kansas, as well as outreach to the general public. The project gathered data on a number of different cases, including LP storms, supercells, and mesoscale convective systems, among others. Many of the storms produced mostly positive CG lightning during significant portions of their lifetimes and also exhibited unusual electrical structures with opposite polarity to ordinary thunderstorms. The field data from STEPS is expected to bring new advances to understanding of supercells, positive CG lightning, TLEs, and precipitation formation in convective storms.

Lang T. J., S. A. Rutledge, and K. C. Wiens, 2004b: Origins of positive cloud-to-ground lightning flashes in the stratiform region of a mesoscale convective system. Geophys. Res. Lett., 31,L10105, doi: 10.1029/2004GL019823.10.1029/2004GL019823

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2004GL019823%2Fcitedby

refpaperuri:(558aca689f62bc2a3a23838c9fdcc025)

http://onlinelibrary.wiley.com/doi/10.1029/2004GL019823/citedbyABSTRACT 7 [1] The origins of positive cloud-to-ground (+CG) 8 lightning in the stratiform region of a leading-line, 9 trailing-stratiform mesoscale convective system (MCS) are 10 investigated. Platforms include radars, NLDN data, and a 11 VHF 3-D lightning mapping system. This study examines a 12 small asymmetric MCS that occurred near the Colorado-13 Kansas border in June 2000. In this storm 39 of the 269 14 +CGs produced over a nearly 5-hour period came to ground 15 within the stratiform region. Of these, 30 initiated in the 16 leading convective line and propagated rearward before 17 coming to ground. Nine other +CGs originated within the 18 stratiform region. Stratiform +CGs were observed to 19 propagate mostly horizontally through vertically thin 20 layers. The observations suggest that stratiform charge is a 21 conduit for +CG lightning from the convective line, and can 22 initiate +CGs as well.

Latham J., A. M. Blyth, H. J. Christian Jr., W. Deierling, and A. M. Gadian, 2004: Determination of precipitation rates and yields from lightning measurements. J. Hydrol., 288( 1-2), 13- 19.10.1016/j.jhydrol.2003.11.009

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0022169403004554

refpaperuri:(36f5b98dd29be31bcb00bb8a0b13953a)

http://www.sciencedirect.com/science/article/pii/S0022169403004554This paper is concerned with the determination of relationships between precipitation rates and lightning flash-rates in thunderstorms.Previous calculations predicting that the lightning frequency is proportional to the product of the downflux of solid precipitation and the mass upflux of ice crystals, have been extended in order to derive direct relationships between and . The form of the /relationship depends upon the dominant glaciation mechanism. If primary nucleation is dominant is proportional to the first power of , but if Hallett–Mossop nucleation prevails the exponent is roughly 1.5. In order to test these predictions adequately, significant additional field-data analysis is required. The estimated values of precipitation yield per lightning flash, , are 10and 2×10kg/flash, respectively. These predictions are in reasonable agreement with field data.Improved predictions of should further increase the reported important role of lightning data—when assimilated into mesoscale models—in improving the accuracy of quantitative precipitation forecasting and shortterm forecasts of flooding.

Li J., B. Wang, and D. H. Wang, 2012: The characteristics of Mesoscale Convective Systems (MCSs) over East Asia in warm seasons. Atmospheric and Oceanic Science Letters, 5( 3), 102- 107.10.1080/16742834.2012.11446973

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http%3A%2F%2Fwww.cnki.com.cn%2FArticle%2FCJFDTotal-AOSL201202006.htm

http://d.wanfangdata.com.cn/Periodical_dqhhykxkb201202005.aspxMesoscale convective system （MCS） cloud clusters,defined using an objective recognition analysis based on hourly geostationary infrared satellite data over East Asia during the warm seasons of 1996-2008 （except 2004）,were investigated in this study.The geographical pattern of MCS distribution over East Asia shows several high-frequency centers at low latitudes,including the Indo-China peninsula,the Bay of Bengal,the Andaman Sea,the Brahmaputra river delta,the south China coastal region,and the Philippine Islands.There are several middle-frequency centers in the middle latitudes,e.g.,the central-east of the Tibet Plateau,the Plateau of west Sichuan,Mount Wuyi,and the Sayan Mountains in Russia;whereas in Lake Baikal,the Tarim Basin,the Taklimakan Desert,the Sea of Japan,and the Sea of Okhotsk,rare MCS distributions are observed.MCSs are most intensely active in summer,with the highest monthly frequency in July,which is partly associated with the breaking out and prevailing of the summer monsoon in East Asia.An obvious diurnal cycle feature is also found in MCS activities,which shows that MCSs are triggered in the afternoon,mature in the evening,and dissipate at night.MCS patterns over East Asia can be characterized as small,short-lived,or elongated,which move slowly and usually lead to heavy rains or floods.

Liu D. X., X. S. Qie, Y. J. Xiong, and G. L. Feng, 2011: Evolution of the total lightning activity in a leading-line and trailing stratiform mesoscale convective system over Beijing. Adv. Atmos. Sci., 28, 866-878, doi: 10.1007/s00376-010-0001-8.10.1007/s00376-010-0001-8

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http%3A%2F%2Fd.wanfangdata.com.cn%2FPeriodical_dqkxjz-e201104013.aspx

refpaperuri:(971e7f256c9b2b0eaf8aa2a13c47f9eb)

http://d.wanfangdata.com.cn/Periodical_dqkxjz-e201104013.aspxData from the Beijing SAFIR 3000 lightning detection system and Doppler radar provided some insights into the three-dimensional lightning structure and evolution of a leading-line and trailing-stratiform (LLTS) mesoscale convective system (MCS) over Beijing on 31 July 2007.Most of the lightning in the LLTS-MCS was intracloud (IC) lightning,while the mean ratio of positive cloud-to-ground (+CG) lightning to -CG lightning was 1:4,which was higher than the average value from previous studies.The majority of CG lightning occurred in the convective region of the radar echo,particularly at the leading edge of the front.Little IC lightning and little +CG lightning occurred in the stratiform region.The distribution of the CG lightning indicated that the storm had a tilted dipole structure given the wind shear or the tripole charge structure.During the storm's development,most of the IC lightning occurred at an altitude of 9.5 km;the lightning rate reached its maximum at 10.5 km,the altitude of IC lightning in the mature stage of the storm.When the thunderstorm began to dissipate,the altitude of the IC lightning decreased gradually.The spatial distribution of lightning was well correlated with the rainfall on the ground,although the peak value of rainfall appeared 75 min later than the peak lightning rate.

Lu G., Coauthors, 2013: Coordinated observations of sprites and in-cloud lightning flash structure. J. Geophys. Res.,118, 6607-6632, doi: 10.1002/jgrd.50459.10.1002/jgrd.50459

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http://onlinelibrary.wiley.com/doi/10.1002/jgrd.50459/pdf

http://onlinelibrary.wiley.com/doi/10.1002/jgrd.50459/pdf[1] The temporal and spatial development of sprite-producing lightning flashes is examined with coordinated observations over an asymmetric mesoscale convective system (MCS) on 29 June 2011 near the Oklahoma Lightning Mapping Array (LMA). Sprites produced by a total of 26 lightning flashes were observed simultaneously on video from Bennett, Colorado and Hawley, Texas, enabling a triangulation of sprites in comparison with temporal development of parent lightning (in particular, negatively charged stepped leaders) in three-dimensional space. In general, prompt sprites produced within 20 ms after the causative stroke are less horizontally displaced (typically 30 km). However, both prompt and delayed sprites are usually centered within 30 km of the geometric center of relevant LMA sources (with affinity to negative stepped leaders) during the prior 100 ms interval. Multiple sprites appearing as dancing/jumping events associated with a single lightning flash could be produced either by distinct strokes of the flash, by a single stroke through a series of current surges superposed on an intense continuing current, or by both. Our observations imply that sprites elongated in one direction are sometimes linked to in-cloud leader structure with the

Lu G., S. A. Cummer, J. B. Li, F. Han, R. J. Blakeslee, and H. J. Christian, 2009: Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system. Geophys. Res. Lett., 36,L15805, doi: 10.1029/2009GL038880.10.1029/2009GL038880

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http://onlinelibrary.wiley.com/doi/10.1029/2009GL038880/full

http://onlinelibrary.wiley.com/doi/10.1029/2009GL038880/full[1] Lightning observations in the very high frequency band and measurements of ultra low frequency magnetic fields are analyzed to investigate the charge transfer and in-cloud structure of eight positive cloud-to-ground (+CG) strokes in a mesoscale convective system. Although no high altitude images were recorded, these strokes contained large charge moment changes (1500 -3200 CAkm) capable of producing nighttime sprites. Even though the convective region of the storm was where the flashes originated and where the CG strokes could occur, the charge transferred to ground was mainly from the stratiform region. The post- stroke long continuing currents were connected to highly branched negative leader extension into the stratiform region. While the storm dissipated, the altitude of negative leader propagation in the stratiform area dropped gradually from 8 to 5 km, indicating that in some and perhaps all of these strokes, it was the upper positive charge in the stratiform region that was transferred. Citation: Lu, G., S. A. Cummer, J. Li, F. Han, R. J. Blakeslee, and H. J. Christian (2009), Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system, Geophys. Res. Lett., 36, L15805, doi:10.1029/2009GL038880.

Lyons W. A., T. E. Nelson, E. R. Williams, S. A. Cummer, and M. A. Stanley, 2003: Characteristics of sprite-producing positive cloud-to-ground lightning during the 19 July 2000 STEPS Mesoscale Convective Systems. Mon. Wea. Rev., 131, 2417- 2427.10.1175/1520-0493(2003)131<2417:COSPCL>2.0.CO;2

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http://www.researchgate.net/publication/228650828_Characteristics_of_sprite-producing_positive_cloud-to-ground_lightning_during_the_19_July_2000_STEPS_mesoscale_convective_systems

http://www.researchgate.net/publication/228650828_Characteristics_of_sprite-producing_positive_cloud-to-ground_lightning_during_the_19_July_2000_STEPS_mesoscale_convective_systemsDuring the summer of 2000, the Severe Thunderstorm Electrification and Precipitation Study (STEPS) program deployed a three-dimensional Lightning Mapping Array (LMA) near Goodland, Kansas. Video confirmation of sprites triggered by lightning within storms traversing the LMA domain were coordinated with extremely low frequency (ELF) transient measurements in Rhode Island and North Carolina. Two techniques of estimating changes in vertical charge moment (Mq) yielded averages of 17800 and 17950 C km for 13 sprite-parent positive polarity cloud-to-ground strokes (17CGs). Analyses of the LMA’s very high frequency (VHF) lightning emissions within the two mesoscale convective systems (MCSs) show that 17CGs did not produce sprites until the centroid of the maximum density of lightning radiation emissions dropped from the upper part of the storm (7–11.5 km AGL) to much lower altitudes (2–5 km AGL). The average height of charge removal (Zq) from 15 sprite-parent 17CGs during the late mature phase of one MCS was 4.1 km AGL. Thus, the total charges lowered by spriteparent 17CGs were on the order of 200 C. The regional 017C isotherm was located at about 4.0 km AGL. This suggests a possible linkage between sprite-parent CGs and melting-layer/brightband c

MacGorman D. R., W. D. Rust, 1999: The Electrical Nature of Storms. Oxford University Press, New York, 422 pp.

Mazur V., W. D. Rust, 1983: Lightning propagation and flash density in squall lines as determined with radar. J. Geophys. Res., 88, 1495- 1502.10.1029/JC088iC02p01495

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2FJC088iC02p01495%2Fabstract

refpaperuri:(4ed6957df46cf73956ed87bebfab6a7b)

http://onlinelibrary.wiley.com/doi/10.1029/JC088iC02p01495/abstractThe propagation of lightning has been studied using radar techniques. The rise time of radar echoes is explained by ionized channel propagation through the radar beam. The calculated values agree well with those obtained experimentally. Measurements of the radial velocity of streamer propagation (along the antenna beam) show speeds of at least 2.5 0 5 m/s. The time-range variations in lightning echoes are indicative of (1) new ionization as streamers develop into different parts of the cloud, (2) channel decay during which adequate ionization exists for radar detection, or (3) continuing current. Lightning flash density has been determined for two squall lines, one in the USSR (using a 2-m wavelength radar) and the other in the United States (using a 23-cm wavelength radar). The United States study shows that the maximum lightning density tends to be near the leading edge of the precipitation cores in developing cells. As a cell in the squall line develops and the total lightning density increases, long discharges are produced, but shorter ones predominate. In contrast, as the cell dissipates, short flashes diminish or cease, and the long flashes dominate the lightning activity.

Mazur V., E. Williams, R. Boldi, L. Maier, and D. E. Proctor, 1997: Initial comparison of lightning mapping with operational time-of-arrival and interferometric systems. J. Geophys. Res.,102(D10), 11 071-11 085, doi: 10.1029/97JD 00174.10.1029/97JD00174

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F97JD00174%2Fcitedby

refpaperuri:(d278717d8effe0ce2d7704018c1ba083)

http://onlinelibrary.wiley.com/doi/10.1029/97JD00174/citedbyThe mapping of lightning radiation sources produced by the operational Time-of-Arrival National Aeronautics and Space Administration/Lightning Detection and Ranging (NASA/LDAR) system is compared with that of the Interferometric French Office National D'Etudes et de Recherches Aerospatiales (ONERA-3D) system. The comparison comprises lightning activity in three Florida storms and also individual flashes in one of these storms. Although limited in scope, the comparison and analysis show a significant difference in the representation of lightning radiation by each mapping system. During the duration of a flash, the LDAR data show a continuity in time and a three-dimensional structure of radiation sources. The ONERA-3D radiation source data are more intermittent in time and have a more two-dimensional structure. The distinction between the radiation sources mapped by the two systems is also reflected in the difference between their propagation speeds, 10 4 –10 5 m s 61l , estimated by the LDAR system, and 10 7 –10 8 m s 611 , estimated by the ONERA-3D system. We infer that this difference occurs because most of the radiation sources mapped with LDAR are associated with virgin breakdown processes typical of slowly propagating negative leaders. On the other hand, most of the radiation sources mapped with ONERA-3D are produced by fast intermittent negative breakdown processes typical of dart leaders and K changes as they traverse the previously ionized channels. Thus each operational system may emphasize different stages of the lightning flash, but neither appears to map the entire flash.

McCaul, E. W. Jr., S. J. Goodman, K. M. LaCasse, D. J. Cecil, 2009: Forecasting lightning threat using cloud-resolving model simulations. Wea. Forecasting, 24, 709- 729.10.1175/2008WAF2222152.1

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http://www.researchgate.net/publication/249612933_Forecasting_Lightning_Threat_Using_Cloud-Resolving_Model_Simulations

http://www.researchgate.net/publication/249612933_Forecasting_Lightning_Threat_Using_Cloud-Resolving_Model_SimulationsAbstract Two new approaches are proposed and developed for making time- and space-dependent, quantitative short-term forecasts of lightning threats, and a blend of these approaches is devised that capitalizes on the strengths of each. The new methods are distinctive in that they are based entirely on the ice-phase hydrometeor fields generated by regional cloud-resolving numerical simulations, such as those produced by the Weather Research and Forecasting (WRF) model. These methods are justified by established observational evidence linking aspects of the precipitating ice hydrometeor fields to total flash rates. The methods are straightforward and easy to implement, and offer an effective near-term alternative to the incorporation of complex and costly cloud electrification schemes into numerical models. One method is based on upward fluxes of precipitating ice hydrometeors in the mixed-phase region at the 15C level, while the second method is based on the vertically integrated amounts of ice hydrometeors in each model grid column. Each method can be calibrated by comparing domain-wide statistics of the peak values of simulated flash-rate proxy fields against domain-wide peak total lightning flash-rate density data from observations. Tests show that the first method is able to capture much of the temporal variability of the lightning threat, while the second method does a better job of depicting the areal coverage of the threat. The blended solution proposed in this work is designed to retain most of the temporal sensitivity of the first method, while adding the improved spatial coverage of the second. Simulations of selected diverse North Alabama cases show that the WRF can distinguish the general character of most convective events, and that the methods employed herein show promise as a means of generating quantitatively realistic fields of lightning threat. However, because the models tend to have more difficulty in predicting the instantaneous placement of storms, forecasts of the detailed location of the lightning threat based on single simulations can be in error. Although these model shortcomings presently limit the precision of lightning threat forecasts from individual runs of current generation models, the techniques proposed herein should continue to be applicable as newer and more accurate physically based model versions, physical parameterizations, initialization techniques, and ensembles of forecasts become available.

Mlawer E. J., S. J. Taubman, P. D. Brown, M. J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the long-wave. J. Geophys. Res., 102( D14), 16 663- 16 682.10.1029/97JD00237

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http://onlinelibrary.wiley.com/doi/10.1029/97JD00237/pdf

http://onlinelibrary.wiley.com/doi/10.1029/97JD00237/pdfABSTRACT A rapid and accurate radiative transfer model (RRTM) for climate applications been developed and the results extensively evaluated. The current version of RRTM calculates fluxes and cooling rates for the longwave spectral region (10-3000 cm-1) for an arbitrary clear atmosphere. The molecular species treated in the model are water vapor, carbon dioxide, ozone, methane, nitrous oxide, and the common halocarbons. The radiative transfer in RRTM is performed using the correlated-k method: the k distributions are attained directly from the LBLRTM line-by-line model, which connects the absorption coefficients used by RRTM to high-resolution radiance validations done with observations. Refined methods have been developed for treating bands containing gases with overlapping absorption, for the determination of values of the Planck function appropriate for use in the correlated-k approach, and for the inclusion of minor absorbing species in a band. The flux and cooling rate results of RRTM are linked to measurement through the use of LBLRTM, which has been substantially validated with observations. Validations of RRTM using LBLRTM have been performed for the midlatitude summer, tropical, midlatitude winter, subarctic winter, and four atmospheres from the Spectral Radiance Experiment campaign. On the basis of these validations the longwave accuracy of RRTM for any atmosphere is as follows: 0.6 W m-2 (relative to LBLRTM) for net flux in each band at all altitudes, with a total (10-3000 cm-1) error of less than 1.0 W m-2 at any altitudes; 0.07 K d-1 for total cooling rate error in the troposphere and lower stratosphere, and 0.75 K d-1 in the upper stratosphere and above. Other comparisons have been performed on RRTM using LBLRTM to gauge its sensitivity to changes in the abundance of specific species, including the halocarbons and carbon dioxide. The radiative forcing due to doubling the concentration of carbon dioxide is attained with an accuracy of 0.24 W m-2, an error of less than 5%. The speed of execution of RRTM compares favorably with that of other rapid radiation models, indicating that the model is suitable for use in general circulation models.

Nielsen K. E., R. A. Maddox, S. V. Vasiloff, 1994: The evolution of cloud-to- ground lightning within a portion of the 10-11 June 1985 squall line. Mon. Wea. Rev., 122, 1809- 1817.10.1175/1520-0493(1994)1222.0.CO;2

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http://www.researchgate.net/publication/23908750_The_evolution_of_cloud-to-ground_lightning_within_a_portion_of_the_10-11_June_1985_squall_line

http://www.researchgate.net/publication/23908750_The_evolution_of_cloud-to-ground_lightning_within_a_portion_of_the_10-11_June_1985_squall_lineAbstract The character of cloud-to-ground lightning is examined during the life cycle of a distinct mesoscale segment of the 1011 June 1985 mesoscale convective system (MCS). Three phases of lightning activity are identified and related to both the radar-observed structure of the convection and to the severe weather produced by the MCS. Positive strikes to ground are dominant when the MCS is first developing. Negative strikes then dominate during a period of intense leading-line convective activity with high storm tops. Finally, a period of relatively frequent positive strikes within the trailing stratiform region occurs during the demise of the MCS. This last phase begins after the vertical extent of the leading convective line decreases rapidly and markedly, with moderate intensity echoes (i.e., 30-40 dBZ) occurring mostly below the freezing level. The first period of frequent positive flashes results from the lightning associated with a single severe thunderstorm in southwest Kansas; however, a second severe storm occurs nearby and produces mainly negative strikes. An extended period of strong surface winds does not appear to have any direct relationship with the observed character of the lightning activity.

Parker M. D., R. H. Johnson, 2000: Organizational modes of midlatitude mesoscale convective systems. Mon. Wea. Rev., 128, 3413- 3436.10.1175/1520-0493(2001)1292.0.CO;2

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F255587652_Organizational_Modes_of_Midlatitude_Mesoscale_Convective_Systems

refpaperuri:(770eca08b0fb32b4fd41d494fa303e9f)

http://www.researchgate.net/publication/255587652_Organizational_Modes_of_Midlatitude_Mesoscale_Convective_SystemsAbstract This paper discusses common modes of mesoscale convective organization. Using 2-km national composite reflectivity data, the authors investigated linear mesoscale convective systems (MCSs) that occurred in the central United States during May 1996 and May 1997. Based upon the radar-observed characteristics of 88 linear MCSs, the authors propose a new taxonomy comprising convective lines with trailing (TS), leading (LS), and parallel (PS) stratiform precipitation. While the TS archetype was found to be the dominant mode of linear MCS organization, the LS and PS archetypes composed nearly 40% of the studied population. In this paper, the authors document the characteristics of each linear MCS class and use operational surface and upper air data to describe their different environments. In particular, wind profiler data reveal that the stratiform precipitation arrangement associated with each class was roughly consistent with the advection of hydrometeors implied by the mean middle- and upper-tropospheric storm-relative winds, which were significantly different among the three MCS modes. Case study examples are presented for both the LS and PS classes, which have received relatively little attention to this point. As well, the authors give a general overview of the synoptic-scale meteorology accompanying linear MCSs in this study, which was generally similar to that observed by previous investigators.

Petersen W. A., H. J. Christian, and S. A. Rutledge, 2005: TRMM observations of the global relationship between ice water content and lightning. Geophys. Res. Lett., 32,L14819, doi: 10.1029/2005GL023236.10.1029/2005GL023236

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2005GL023236%2Fabstract

refpaperuri:(481c0a4029b4b9fd4dd71f20f5a85eda)

http://onlinelibrary.wiley.com/doi/10.1029/2005GL023236/abstract[1] This study uses TRMM lightning and radar observations to study the fundamental relationship between precipitation ice mass and lightning flash density. The results indicate that the physical assumptions of precipitation-based charging and mixed phase precipitation development are robust and that on a global scale , the relationship between precipitation ice water path and lightning flash density is relatively invariant between land, ocean and coastal regimes. Hence lightning data may be a useful variable for inclusion in combined space borne algorithms designed to retrieve ice water content.

Rutledge S. A., D. R. MacGorman, 1988: Cloud-to-ground lightning activity in the 10-11 June 1985 mesoscale convective system observed during the Oklahoma-Kansas PRE-STORM project. Mon. Wea. Rev., 116, 1393- 1408.10.1175/1520-0493(1988)116<1393:CTGLAI>2.0.CO;2

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e0cc3084833a1b4812dd67e541cb9ff2

http://www.researchgate.net/publication/249620272_Cloud-to-Ground_Lightning_Activity_in_the_1011_June_1985_Mesoscale_Convective_System_Observed_during_the_OklahomaKansas_PRE-STORM_Project

http://www.researchgate.net/publication/249620272_Cloud-to-Ground_Lightning_Activity_in_the_1011_June_1985_Mesoscale_Convective_System_Observed_during_the_OklahomaKansas_PRE-STORM_ProjectABSTRACT

Rutledge S. A., R. A. Houze Jr., M. I. Biggerstaff, and T. Matejka, 1988: The Oklahoma-Kansas mesoscale convective system of 10-11 June 1985: Precipitation structure and single-Doppler radar analysis. Mon. Wea. Rev., 116, 1409- 1430.10.1175/1520-0493(1988)1162.0.CO;2

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http://www.researchgate.net/publication/240688876_The_OklahomaKansas_Mesoscale_Convective_System_of_1011_June_1985_Precipitation_Structure_and_Single-Doppler_Radar_Analysis

http://www.researchgate.net/publication/240688876_The_OklahomaKansas_Mesoscale_Convective_System_of_1011_June_1985_Precipitation_Structure_and_Single-Doppler_Radar_AnalysisAbstract The 10–11 June mesoscale convective system observed in Kansas during PRE-STORM is studied using a variety of observations including conventional radar, satellite, and single-Doppler radar. This storm, at maturity, consisted of a strong line of convection trailed by a broad region of stratiform rain. The PRE-STORM Doppler radar observations show that the general airflow pattern is similar to that seen in previously analyzed cases; however, since the Doppler observations were quite extensive in time and space, they permit several details of the airflow to be revealed for the first time. A rear inflow jet, front-to-rear flow aloft, and a mesoscale updraft and downdraft were all present. The mesoscale downdraft commenced at the top of the slanted rear inflow jet. Sublimation and evaporation of hydrometeors in this flow apparently generated the necessary cooling to drive the mesoscale downdraft circulation. The intensity and slope of the rear inflow jet varied with location in the storm, which apparently led to differences in both the intensity and depth of the mesoscale downdraft. The intrusion of this inflow jet into the rear of storm occurred at quite high levels and was probably responsible for disruption of the continuous oval cloud shield as viewed by satellite. The front-to-rear flow situated above the rear inflow jet contained mesoscale upward motion. Vertical velocities obtained by the EVAD (Extended Velocity–Azimuth Display) method reveal a strong mesoscale updraft, with speeds approaching 50 cm s 611 . Vertically pointing observations indicated that convective-scale updrafts and downdrafts were present within 20 km of the convective line. Convective-scale features were not observed in the remaining portion of the trailing stratiform region.

Smull B. F., R. A. Houze Jr., 1985: A midlatitude squall line with a trailing region of stratiform rain: Radar and satellite observations. Mon. Wea. Rev., 113, 117- 133.10.1175/1520-0493(1985)113<0117:AMSLWA>2.0.CO;2

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F240688805_A_Midlatitude_Squall_Line_with_a_Trailing_Region_of_Stratiform_Rain_Radar_and_Satellite_Observations

refpaperuri:(5bf2e9a8fa46cdabfe68b673d88a3040)

http://www.researchgate.net/publication/240688805_A_Midlatitude_Squall_Line_with_a_Trailing_Region_of_Stratiform_Rain_Radar_and_Satellite_ObservationsAbstract A squall line exhibiting an extensive trailing region of stratiform precipitation passed over the observational network of the National Severe Storms Laboratory on 22 May 1976. Satellite imagery and conventional radar observations document its evolution from a broken line of thunderstorms to a system of mesoscale proportions, and single-Doppler radar observations describe aspects of its mature structure. Satellite measurements of cloud-top temperature showed the system to be a mesoscale convective complex (MCC). The life cycle of the system exhibited the stages of development seen in tropical cloud clusters. At maturity, two prominent mesoscale flow regimes were identified at midlevels: one marked by inflow into the system's front and continuing toward its rear, and another associated with inflow entering the extreme rear of the system. The rear inflow was associated with a cyclonic midlevel vortex in the stratiform precipitation region. It produced a concavity, or otch, in the back edge of the precipitation echo. Shortly after the appearance of the notch, a downwind segment of the leading convective line accelerated forward. The notch persisted through the dissipating stage, at which time secondary notches also formed. The last remnant of the stratiform precipitation area took the form of a chain of three comma-shaped vortices, whose origin could be traced in time back to the primary and secondary notches. The inflow at the front of the system spanned both the leading convective and trailing stratiform regions. Convective-scale velocity maxima were superimposed on this front-to-rear flow in the convective region, while a broad maximum of the rearward current occurred in the stratiform region, just above the melting layer. This rearward system-relative flow apparently promoted the broad structure of the precipitation area. Slowly falling ice particles originating at convective cell tops were evidently advected rearward and dispersed over a 50-100 km wide region, whereupon their melting produced a prominent radar bright band.

Stensrud D. J., M. C. Coniglio, R. P. Davies-Jones, and J. S. Evans, 2005: Comments on "`A theory for strong long-lived squall lines' revisited". J. Atmos. Sci., 62, 2989- 2996.10.1175/JAS3514.1

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http://www.researchgate.net/publication/234215601_Comments_on_A_Theory_for_Strong_Long-Lived_Squall_Lines'_Revisited''

http://www.researchgate.net/publication/234215601_Comments_on_A_Theory_for_Strong_Long-Lived_Squall_Lines'_Revisited''Comments on the article "A Theory for Strong Long-Lived Squall Lines," by R. Rotunno, J.B. Klemp and M.L. Weisman, published previously in the "Journal of Atmospheric Sciences." Proposal of an optimal state of squall lines made by Weisman and colleagues, in which the relative strength of the circulation associated with the storm-generated cold pool and the circulation associated with the environmental shear are balanced; Opinion that ambient shear is an important factor in the dynamics of squall lines; Assessment of the two-dimensional vorticity-streamfunction model that shows that the maximum vertical displacement of low-level air parcels occurs when only low-level shear is present in the environmental wind profile.

Thomas R. J., P. R. Krehbiel, W. Rison, S. J. Hunyady, W. P. Winn, T. Hamlin, and J. Harlin, 2004: Accuracy of the lightning mapping array. J. Geophys. Res., 109,D14207, doi: 10.1029/2004JD004549.10.1029/2004JD004549

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2004JD004549%2Fpdf

refpaperuri:(128e0c300f772d95ac565d50355e1b78)

http://onlinelibrary.wiley.com/doi/10.1029/2004JD004549/pdf[1] The location accuracy of the New Mexico Tech Lightning Mapping Array (LMA) has been investigated experimentally using sounding balloon measurements, airplane tracks, and observations of distant storms. We have also developed simple geometric models for estimating the location uncertainty of sources both over and outside the network. The model results are found to be a good estimator of the observed errors and also agree with covariance estimates of the location uncertainties obtained from the least squares solution technique. Sources over the network are located with an uncertainty of 6-12 m rms in the horizontal and 20-30 m rms in the vertical. This corresponds well with the uncertainties of the arrival time measurements, determined from the distribution of chi-square values to be 40-50 ns rms. Outside the network the location uncertainties increase with distance. The geometric model shows that the range and altitude errors increase as the range squared, r 2 , while the azimuthal error increases linearly with r . For the 13 station, 70 km diameter network deployed during STEPS the range and height errors of distant sources were comparable to each other, while the azimuthal errors were much smaller. The difference in the range and azimuth errors causes distant storms to be elongated radially in plan views of the observations. The overall results are shown to agree well with hyperbolic formulations of time of arrival measurements [e.g., Proctor , 1971 ]. Two appendices describe (1) the basic operation of the LMA and the detailed manner in which its measurements are processed and (2) the effect of systematic errors on lightning observations. The latter provides an alternative explanation for the systematic height errors found by Boccippio et al. [2001] in distant storm data from the Lightning Detection and Ranging system at Kennedy Space Center.

Wang K. Y., S. A. Liao, 2006: Lightning, radar reflectivity, infrared brightness temperature, and surface rainfall during the 2-4 July 2004 severe convective system over Taiwan area. J. Geophys. Res., 111,D05206, doi: 10.1029/2005JD006411.10.1029/2005jd006411

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http://onlinelibrary.wiley.com/doi/10.1029/2005JD006411/pdf/enhanced

http://onlinelibrary.wiley.com/doi/10.1029/2005JD006411/pdf/enhanced提供台灣中央大學的博碩士論文、考古題、期刊論文、研究計畫等下載

Weisman M. L., R. Rotunno, 2004: "A theory for strong long-lived squall lines" revisited. J. Atmos. Sci., 61, 361- 382.10.1175/1520-0469(2004)061<0361:ATFSLS>2.0.CO;2

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http://www.researchgate.net/publication/240686623_A_Theory_for_Strong_Long-Lived_Squall_Lines''_Revisited

http://www.researchgate.net/publication/240686623_A_Theory_for_Strong_Long-Lived_Squall_Lines''_RevisitedBased on the analysis of idealized two- and three-dimensional cloud model simulations, Rotunno et al. (hereafter RKW) and Weisman et al. (hereafter WKR) put forth a theory that squall-line strength and longevity was most sensitive to the strength of the component of low-level (0093 km AGL) ambient vertical wind shear perpendicular to squall-line orientation. An 0904optimal0909 state was proposed by, based on the relative strength of the circulation associated with the storm-generated cold pool and the circulation associated with the ambient shear, whereby the deepest leading edge lifting and most effective convective retriggering occurred when these circulations were in near balance. Since this work, subsequent studies have brought into question the basic validity of the proposed optimal state, based on concerns as to the appropriate distribution of shear relative to the cold pool for optimal lifting, as well as the relevance of such concepts to fully complex squall lines, especially considering the potential role of deeper-layer shears in promoting system strength and longevity. In the following, the basic interpretations of thetheory are reconfirmed and clarified through both the analysis of a simplified two-dimensional vorticity09treamfunction model that allows for a more direct interpretation of the role of the shear in controlling the circulation around the cold pool, and through an analysis of an extensive set of 3D squall-line simulations, run at higher resolution and covering a larger range of environmental shear conditions than presented by.

Weisman M. L., J. B. Klemp, and R. Rotunno, 1988: Structure and evolution of numerically simulated squall lines. J. Atmos. Sci., 45, 1990- 2013.10.1175/1520-0469(1988)0452.0.CO;2

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F234200493_Structure_and_Evolution_of_Numerically_Simulated_Squall_Lines

refpaperuri:(b66812ac778817d498bc5c86e491f0f8)

http://www.researchgate.net/publication/234200493_Structure_and_Evolution_of_Numerically_Simulated_Squall_LinesABSTRACT Using a three-dimensional numerical cloud model, we investigate the effects of vertical wind shear on squall-line structure and evolution over a wide range of shear magnitudes, depths, and orientations relative to the line. We find that the simulated squall lines are most sensitive to the magnitude of the component of shear perpendicular to the line, and that we may reproduce much of the range of observed structures by varying this single parameter. For weak shear, a line of initially upright-to-downshear-tilted short-lived cells quickly tilts upshear, producing a wide band of weaker cells extending behind the surface outflow boundary. For moderate-to-strong shear, the circulation remains upright-to-downshear tilted for longer periods of time, with vigorous, short-lived cells confined to a relatively narrow band along the system's leading edge. At later times, however, these systems may also weaken as the circulation tilts upshear. For strong, deep shears oriented obliquely to the line, the squall line may be composed of quasi-steady, three-dimensional supercells. The squall-line lifecyle that occurs in most of the simulations is dependent on both the strength of the developing cold pool, which induces an upshear-tilted circulation, and the strength of the ambient low-level shear ahead of the line, which promotes a circulation tilting the system downshear. When these two factors are in balance, the overall system circulation remains upright, and we obtain the optimal conditions for deep lifting that promotes the regeneration of strong cells along the outflow boundary. In the current experiments, this optimal state occurs with 15-25 m s1 of velocity change over the lowest 2.5 km AGL.

Wiens K. C., S. A. Rutledge, and S. A. Tessendorf, 2005: The 29 June 2000 supercell observed during steps. Part II: Lightning and charge structure. J. Atmos. Sci., 62, 4151- 4177.10.1175/JAS3615.1

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F255616286_The_29_June_2000_Supercell_Observed_during_STEPS._Part_II_Lightning_and_Charge_Structure

refpaperuri:(e5c8ead870ca42c3790c55436fd60ae8)

http://www.researchgate.net/publication/255616286_The_29_June_2000_Supercell_Observed_during_STEPS._Part_II_Lightning_and_Charge_StructureAbstract This second part of a two-part study examines the lightning and charge structure evolution of the 29 June 2000 tornadic supercell observed during the Severe Thunderstorm Electrification and Precipitation Study (STEPS). Data from the National Lightning Detection Network and the New Mexico Tech Lightning Mapping Array (LMA) are used to quantify the total and cloud-to-ground (CG) flash rates. Additionally, the LMA data are used to infer gross charge structure and to determine the origin locations and charge regions involved in the CG flashes. The total flash rate reached nearly 300 min 611 and was well correlated with radar-inferred updraft and graupel echo volumes. Intracloud flashes accounted for 95%–100% of the total lightning activity during any given minute. Nearly 90% of the CG flashes delivered a positive charge to ground (+CGs). The charge structure during the first 20 min of this storm consisted of a midlevel negative charge overlying lower positive charge with no evidence of an upper positive charge. The charge structure in the later (severe) phase was more complex but maintained what could be roughly described as an inverted tripole, dominated by a deep midlevel (5–9 km MSL) region of positive charge. The storm produced only two CG flashes (both positive) in the first 2 h of lightning activity, both of which occurred during a brief surge in updraft and hail production. Frequent +CG flashes began nearly coincident with dramatic increases in storm updraft, hail production, total flash rate, and the formation of an F1 tornado. The +CG flashes tended to cluster in or just downwind of the heaviest precipitation, which usually contained hail. The +CG flashes all originated between 5 and 9 km MSL, centered at 6.8 km (6110°C), and tapped LMA-inferred positive charge both in the precipitation core and (more often) in weaker reflectivity extending downwind. All but one of the 61CG flashes originated from >9 km MSL and tended to strike near the precipitation core.

Xue M., D. H. Wang, J. D. Gao, K. Brewster, and K. K. Droegemeier, 2003: The advanced regional prediction system (ARPS), storm-scale numerical weather prediction and data assimilation. Meteor. Atmos. Phys., 82, 139- 170.10.1007/s00703-001-0595-6

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http%3A%2F%2Fwww.springerlink.com%2Findex%2FCG08L17MKCFAHA14.pdf

refpaperuri:(3262b14f9cfb89886879ad763abd2717)

http://www.springerlink.com/index/CG08L17MKCFAHA14.pdfSummaryIn this paper, we first describe the current status of the Advanced Regional Prediction System of the Center for Analysis and Prediction of Storms at the University of Oklahoma. A brief outline of future plans is also given. Two rather successful cases of explicit prediction of tornadic thunderstorms are then presented. In the first case, a series of supercell storms that produced a historical number of tornadoes was successfully predicted more than 8 hours in advance, to within tens of kilometers in space with initiation timing errors of less than 2 hours. The general behavior and evolution of the predicted thunderstorms agree very well with radar observations. In the second case, reflectivity and radial velocity observations from Doppler radars were assimilated into the model at 15-minute intervals. The ensuing forecast, covering a period of several hours, accurately reproduced the intensification and evolution of a tornadic supercell that in reality spawned two tornadoes over a major metropolitan area. These results make us optimistic that a model system such as the ARPS will be able to deterministically predict future severe convective events with significant lead time. The paper also includes a brief description of a new 3DVAR system developed in the ARPS framework. The goal is to combine several steps of Doppler radar retrieval with the analysis of other data types into a single 3-D variational framework and later to incorporate the ARPS adjoint to establish a true 4DVAR data assimilation system that is suitable for directly assimilating a wide variety of observations for flows ranging from synoptic down to the small nonhydrostatic scales.

Yair, Y., Coauthors, 2010: Predicting the potential for lightning activity in Mediterranean storms based on the Weather Research and Forecasting (WRF) model dynamic and microphysical fields. J. Geophys. Res., 115, D04205, doi: 10.1029/ 2008JD010868.10.1029/2008JD010868

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2008JD010868%2Fabstract

refpaperuri:(f205da13658a16bbfe7381532f15adfe)

http://onlinelibrary.wiley.com/doi/10.1029/2008JD010868/abstract[1] A new parameter is introduced: the lightning potential index (LPI), which is a measure of the potential for charge generation and separation that leads to lightning flashes in convective thunderstorms. The LPI is calculated within the charge separation region of clouds between 0°C and 6120°C, where the noninductive mechanism involving collisions of ice and graupel particles in the presence of supercooled water is most effective. As shown in several case studies using the Weather Research and Forecasting (WRF) model with explicit microphysics, the LPI is highly correlated with observed lightning. It is suggested that the LPI may be a useful parameter for predicting lightning as well as a tool for improving weather forecasting of convective storms and heavy rainfall.

Zhao K., M. Xue, 2009: Assimilation of coastal Doppler radar data with the ARPS 3DVAR and cloud analysis for the prediction of Hurricane Ike (2008). Geophys. Res. Lett., 36,L12803, doi: 10.1029/2009GL038658.10.1029/2009GL038658

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2009GL038658%2Fcitedby

refpaperuri:(00f9d1dd64e0111444bae5b8be398592)

http://onlinelibrary.wiley.com/doi/10.1029/2009GL038658/citedby[1] The impact of radar data on the analysis and prediction of the structure, intensity, and track of landfalling Hurricane Ike (2008), at a cloud-resolving resolution, is examined. Radial velocity (Vr) and reflectivity (Z) data from coastal radars are assimilated over a 6-h period before Ike landfall, using the ARPS 3DVAR and cloud analysis package through 30-min assimilation cycles. Eighteen-hour predictions were made. All 4 experiments that assimilate radar data produce better structure, intensity and precipitation forecasts than that from operational GFS analysis. The improvement to the track forecast lasts for the entire 18 hours while that to intensity prediction lasts about 12 hours. The Vr data help improve the track forecast more while reflectivity data help improve intensity forecast most. Best results are obtained when both Z and Vr data are assimilated.

Zheng D., Y. J. Zhang, Q. Meng, W. T. Lv, and X. Y. Yi., 2009: Total lightning characteristics and electric structure evolution in a hailstorm. Acta Meteorologica Sinica, 23, 233- 249.10.1029/2008SW000412

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http%3A%2F%2Fwww.cnki.com.cn%2FArticle%2FCJFDTotal-QXXW200902010.htm

refpaperuri:(0a83e11a088da36a48196936f2be8b12)

http://d.wanfangdata.com.cn/Periodical_qxxb-e200902009.aspxIn this paper, total lightning data observed by SAFIR3000 3-D Lightning Locating System was combined with radar data to analyze characteristics of the lightning activity and electric structure of a hailstorm that occurred in Beijing on 31 May 2005. The results indicated that there were two active periods for the lightning activity during the hailstorm process. The hail shooting was found in the first period. After the end of the hail shooting, lightning frequency decreased suddenly. However, more active lightning activities occurred in the second period with lots of them appearing in the cloud anvil region. The peak of the lightning frequency came about 5 rain prior to the hail shooting. Only 6.16% of the total lightning was cloud-to-ground (CG) lightning, among which 20% had positive polarity. This percentage was higher than that in normal thunderstorms. In addition, heavier positive CG lightning discharge occurred before rather than after the hail shooting. In the stage of the hail shooting, the electric structure of the hailstorm was inverted, with the main negative charge region located around the -40 level and the main positive charge region around the -15 level. In addition, a weak negative charge region existed below the positive charge region transitorily. After the hail shooting, the electric structure underwent fast and persistent adjustments and became a normal tripole, with positive charge in the upper and lower levels and negative charge in the middle levels. However, the electric structure was tilted under the influence of the westerly wind in the middle and upper levels. The lightning activity and electric structure were closely related to the dynamic and microphysical processes of the hailstorm. It was believed that severe storms with stronger updrafts were more conducive to an inverted tripolar electric structure than normal thunderstorms, and the inverted distribution could then facilitate more positive CG lightning in the severe storms.

Zhu G. F., S. J. Chen, 2003: Analysis and comparison of mesoscale convective systems over the Qinghai-Xizang (Tibetan) Plateau. Adv. Atmos. Sci.,20(3), 311-322, doi: 10.1007/BF02690789.10.1007/BF02690789

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http%3A%2F%2Fen.cnki.com.cn%2FArticle_en%2FCJFDTOTAL-DQJZ200303000.htm

refpaperuri:(62ceb0fe2d89ea183ed6472648c0d2ea)

http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQJZ200303000.htmA series of mesoscale convective systems (MCSs) occurred daily over the Qinghai-Xizang Plateau during 25-28 July 1995. In this paper, their physical characteristics and evolutions based on infrared satellite imagery, their largescale meteorological conditions, and convective available potential energy (CAPE) are analyzed. It is found that similar diurnal evolution is present in all these MCSs. Their initial convective activities became active at noon LST by solar heating, and then built up rapidly. They formed and reached a peak in the early evening hours around 1800 LST and then abated gradually. Among them, the strongest and largest is the MCS on 26 July, which developed under the conditions of the great upper-level nearly-circular Qinghai-Xizang anticyclonic high and driven by the strong low-level thermal forcing and conditional instability. All these conditions are intimately linked with the thermal effects of the plateau itself. So its development was mainly associated with the relatively pure thermal effects peculiar to the Qinghai-Xizang Plateau. The next strongest one is the MCS on 28 July, which was affected notably by the baroclinic zone linked with the westerly trough. There are different features and development mechanisms between these two strongest MCSs.