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2. Winter Lightning to the Lee of Lake Ontario: The Lake-Effect Electrification (LEE) Field Campaign.

Author

Steiger, Scott M., Bruning, Eric C., Chmielewski, Vanna C., Stano, Geoffrey, Trostel, John, Calhoun, Kristin M., Jesmonth, Kaitlyn R., Lamsma, Bee, Lang, Timothy, Laurinaitis, Shaun, Losego, Jessica, Ringhausen, Jacquelyn S., Stock, Michael, Wang, Yonggang, Waugh, Sean M., Weiss, Stephanie A., Weist, Thomas, and White, Thomas

Subjects
SUMMER storms, ATMOSPHERIC electricity, CYCLONES, STORMS, SOLAR panels, WINTER storms
Abstract

The National Science Foundation–sponsored Lake-Effect Electrification (LEE) field campaign intensive observation periods occurred between November and early February 2022–23 across the eastern Lake Ontario region. Project LEE documented, for the first time, the total lightning and electrical charge structures of lake-effect storms and the associated storm environment using a lightning mapping array (LMA), a mobile dual-polarization X-band radar, and balloon-based soundings that measured vertical profiles of temperature, humidity, wind, electric field, and hydrometeor types. LEE also observed abundant wind turbine-initiated lightning, which is climatologically more likely during the winter. The frequent occurrence of intense lake-effect storms and the proximity of a wind farm with nearly 300 turbines each more than 100 m tall to the lee of Lake Ontario provided an ideal laboratory for this study. The field project involved many undergraduate (>20) and graduate students. Some foreseen and unforeseen challenges included clearing the LMA solar panels of snow and continuous operation in low-sunlight conditions, large sonde balloons prematurely popping due to extremely cold conditions, sonde line breaking, recovering probes in deep snow in heavily forested areas, vehicles getting stuck in the snowpack, and an abnormally dry season for parts of the LEE domain. In spite of these difficulties, a dataset was collected in multiple lake-effect snowstorms (11 observation periods) and one extratropical cyclone snowstorm that clarifies the electrical structure of these systems. A key finding was the existence of a near-surface substantial positive charge layer (1 nC m−3) near the shoreline during lake-effect thunderstorms. SIGNIFICANCE STATEMENT: Winter lightning is an exciting phenomenon and important to study as man-made objects (e.g., wind turbines) can be more likely to be struck this time of year. We involved over 20 undergraduate students in collecting total lightning, mobile radar, and sounding (e.g., electric field) data in several lake-effect storms. These storms have been known to have substantial electrification and occur many times each winter in a small, consistent region east of Lake Ontario. We analyzed 246 lightning flashes from the main data collection period, and over a third of them were associated with towers. The results from this study will have impacts on our general understanding of electrification in winter and summer storms. [ABSTRACT FROM AUTHOR]

Published
2024
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7. Automated and Objective Thunderstorm Identification and Tracking Using Geostationary Lightning Mapper (GLM) Data.

Author

Murphy, Kelley M., Carey, Lawrence D., Schultz, Christopher J., Curtis, Nathan, and Calhoun, Kristin M.

Subjects
STORMS, LIGHTNING, THUNDERSTORMS
Abstract

A unique storm identification and tracking method is analyzed in varying storm environments within the United States spanning 273 hours in 2018. The methodology uses a quantity calculated through fusion of radar-based vertically integrated liquid (VIL) and satellite-based GLM flash rate density (FRD) called VILFRD to identify storms in space and time. This research analyzes GLM data use within VILFRD for the first time (method original: O), assesses four modifications to VILFRD implementation to find a more stable storm size with time (method new: N), larger storms (method original dilated: OD), or both (method new dilated: ND), and compares VILFRD methods with storm tracking using the 35-dBZ isosurface at −10°C (method non-VILFRD: NV). A case study analysis from 2019 is included to assess methods on a smaller scale and introduce a "lightning only" (LO) version of VILFRD. Large study results highlight that VILFRD-based storm identification produces smaller storms with more lightning than the NV method, and the NV method produces larger storms with a more stable size over time. Methods N and ND create smaller storm size fluctuations, but size changes more often. Dilation (OD, ND) creates larger storms and almost double the number of storms identified relative to nondilated methods (O, N, NV). The case study results closely resemble the large sample results and show that the LO method identifies storms with more lightning and shorter durations. Overall, these findings can aid in choice of storm tracking method based on desired user application and promote further testing of a lightning-only version of VILFRD. [ABSTRACT FROM AUTHOR]

Published
2024
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8. Comment–Reply Exchanges: Trends and Suggestions

Author

Bunkers, Matthew, primary, Allen, John, additional, Ashley, Walker, additional, Bieda, Stephen, additional, Calhoun, Kristin, additional, Kirtman, Benjamin, additional, Kosiba, Karen, additional, Mahoney, Kelly, additional, McMurdie, Lynn, additional, Potvin, Corey, additional, Pu, Zhaoxia, additional, and Ritchie, Elizabeth, additional

Published
2023
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10. Advantages to Writing Shorter Articles

Author

Bunkers, Matthew, primary, Lackmann, Gary, additional, Allen, John, additional, Ashley, Walker, additional, Bieda, Stephen, additional, Calhoun, Kristin, additional, Kirtman, Benjamin, additional, Kosiba, Karen, additional, Mahoney, Kelly, additional, McMurdie, Lynn, additional, Potvin, Corey, additional, Pu, Zhaoxia, additional, and Ritchie, Elizabeth, additional

Published
2023
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13. Early Assessment of the Geostationary Lightning Mapper

Author

Stano, Geoffrey T, Gravelle, Chad M, Foster, Matthew, Bruning, Eric, Rudlosky, Scott D, Zajic, Joseph K, Byerle, Lee A, Guilot, Eric, Calhoun, Kristin M, Gockel, Brian, and Runk, Kim

Subjects
Meteorology And Climatology
Published
2019

18. Assessment of the Pseudo Geostationary Lightning Mapper Products at the Spring Program and Summer Experiment

Author

Stano, Geoffrey T, Calhoun, Kristin K, and Terborg, Amanda M

Subjects
Meteorology And Climatology
Abstract

Since 2010, the de facto Geostationary Lightning Mapper (GLM) demonstration product has been the Pseudo‐Geostationary Lightning Mapper (PGLM) product suite. Originally prepared for the Hazardous Weather Testbed's Spring Program (specifically the Experimental Warning Program) when only four ground‐based lightning mapping arrays were available, the effort now spans collaborations with several institutions and eight collaborative networks. For 2013, NASA's Short‐term Prediction Research and Transition (SPoRT) Center and NOAA's National Severe Storms Laboratory have worked to collaborate with each network to obtain data in real‐time. This has gone into producing the SPoRT variant of the PGLM that was demonstrated in AWIPS II for the 2013 Spring Program. Alongside the PGLM products, the SPoRT / Meteorological Development Laboratory's total lightning tracking tool also was evaluated to assess not just another visualization of future GLM data but how to best extract more information while in the operational environment. Specifically, this tool addressed the leading request by forecasters during evaluations; provide a time series trend of total lightning in real‐time. In addition to the Spring Program, SPoRT is providing the PGLM "mosaic" to the Aviation Weather Center (AWC) and Storm Prediction Center. This is the same as what is used at the Hazardous Weather Testbed, but combines all available networks into one display for use at the national centers. This year, the mosaic was evaluated during the AWC's Summer Experiment. An important distinction between this and the Spring Program is that the Summer Experiment focuses on the national center perspective and not at the local forecast office level. Specifically, the Summer Experiment focuses on aviation needs and concerns and brings together operational forecaster, developers, and FAA representatives. This presentation will focus on the evaluation of SPoRT's pseudo‐GLM products in these separate test beds. The emphasis will be on how future GLM observations can support operations at both the local and national scale and how the PGLM was used in combination with other lightning data sets. Evaluations for the PGLM were quite favorable with forecasters appreciating the high temporal resolution, the ability to look for rapid increases in lightning activity ahead of severe weather, as well as situational awareness for where convection is firing and for flight routing.

Published
2014

19. A Total Lightning Perspective of the 20 May 2013 Moore, Oklahoma Supercell

Author

Stano, Geoffrey T, Schultz, Christopher J, Carey, Lawrence D, MacGorman, Don R, and Calhoun, Kristin M

Subjects
Meteorology And Climatology
Abstract

In the early afternoon of 20 May 2013, a storm initiated to the west‐southwest of Newcastle, Oklahoma. This storm would rapidly intensify into the parent supercell of the tornado that struck the city of Moore, Oklahoma. This article describes what contributions total lightning observations from the Oklahoma Lightning Mapping Array could provide to operational forecasters had these observations been available in real‐time. This effort includes a focus on the GOES‐R pseudo‐geostationary lightning mapper demonstration product as well as the NASA SPoRT / Meteorological Development Laboratory's total lightning tracking tool. These observations and tools identified several contributions. Two distinct lightning jumps at 1908 and 1928 UTC provided a lead time of 19 minutes ahead of severe hail and 26 minutes ahead of the Moore, Oklahoma tornado's touchdown. These observations provide strong situational awareness to forecasters, as the lightning jumps are related to the rapid strengthening of the storm's updraft and mesocyclone and serve as a precursor to the stretching of the storm vortex ahead severe weather.

Published
2014

20. Exploring Lightning Jump Characteristics

Author

Chronis, Themis, Carey, Larry D, Schultz, Christopher J, Schultz, Elise, Calhoun, Kristin, and Goodman, Steven J

Subjects
Meteorology And Climatology
Abstract

This study is concerned with the characteristics of storms exhibiting an abrupt temporal increase in the total lightning flash rate (i.e., lightning jump, LJ). An automated storm tracking method is used to identify storm "clusters" and total lightning activity from three different lightning detection systems over Oklahoma, northern Alabama and Washington, D.C. On average and for different employed thresholds, the clusters that encompass at least one LJ (LJ1) last longer, relate to higher Maximum Expected Size of Hail, Vertical Integrated Liquid and lightning flash rates (area-normalized) than the clusters that did not exhibit any LJ (LJ0). The respective mean values for LJ1 (LJ0) clusters are 80 min (35 min), 14 mm (8 mm), 25 kg per square meter (18 kg per square meter) and 0.05 flash per min per square kilometer (0.01 flash per min per square kilometer). Furthermore, the LJ1 clusters are also characterized by slower decaying autocorrelation functions, a result that implies a less "random" behavior in the temporal flash rate evolution. In addition, the temporal occurrence of the last LJ provides an estimate of the time remaining to the storm's dissipation. Depending of the LJ strength (i.e., varying thresholds), these values typically range between 20-60 min, with stronger jumps indicating more time until storm decay. This study's results support the hypothesis that the LJ is a proxy for the storm's kinematic and microphysical state rather than a coincidental value.

Published
2014

24. Meteorological Imagery for the Geostationary Lightning Mapper

Author

Bruning, Eric C., primary, Tillier, Clemens E., additional, Edgington, Samantha F., additional, Rudlosky, Scott D., additional, Zajic, Joe, additional, Gravelle, Chad, additional, Foster, Matt, additional, Calhoun, Kristin M., additional, Campbell, P. Adrian, additional, Stano, Geoffrey T., additional, Schultz, Christopher J., additional, and Meyer, Tiffany C., additional

Published
2019
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27. Antenna structures and cloud-to-ground lightning location : 1995–2015

Author

Kingfield, Darrel M., Calhoun, Kristin M., de Beurs, Kirsten M., Kingfield, Darrel M., Calhoun, Kristin M., and de Beurs, Kirsten M.

Abstract

Spatial analyses of cloud-to-ground (CG) lightning occurrence due to a rapid expansion in the number of antenna towers across the United States are explored by gridding 20 years of National Lightning Detection Network data at 500 m spatial resolution. The 99.8% of grid cells with ≥100 CGs were within 1 km of an antenna tower registered with the Federal Communications Commission. Tower height is positively correlated with CG occurrence; towers taller than 400 m above ground level experience a median increase of 150% in CG lightning density compared to a region 2 km to 5 km away. In the northern Great Plains, the cumulative CG lightning density near the tower was around 138% (117%) higher than a region 2 to 5 km away in the September–February (March–August) months. Higher CG frequencies typically also occur in the first full year following new tower construction, creating new lightning hot spots.

Published
2017

29. CORRIGENDUM

Author

Fierro, Alexandre O., primary, Gao, Jidong, additional, Ziegler, Conrad L., additional, Calhoun, Kristin M., additional, Mansell, Edward R., additional, and Macgorman, Donald R., additional

Published
2017
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