Performance Assessment of the Optical Transient Detector and Lightning Imaging Sensor. Part I: Predicted Diurnal Variability

Abstract. The satellite instruments Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS) provide unique empirical data about the frequency of lightning flashes around the globe (OTD), and the tropics (LIS), which have been used before to compile a well received global climatology of flash rate densities. Here we present a statistical analysis of various additional lightning properties derived from OTD/LIS, i.e. the number of so-called "events" and "groups" per flash, as well as the mean flash duration, footprint and radiance. These normalized quantities, which can be associated with the flash "strength", show consistent spatial patterns; most strikingly, oceanic flashes show higher values than continental flashes for all properties. Over land, regions with high (Eastern US) and low (India) flash strength can be clearly identified. We discuss possible causes and implications of the observed regional differences. Although a direct quantitative interpretation of the investigated flash properties is difficult, the observed spatial patterns provide valuable information for the interpretation and application of climatological flash rates. Due to the systematic regional variations of physical flash characteristics, viewing conditions, and/or measurement sensitivities, parametrisations of lightning NOx based on total flash rate densities alone are probably affected by regional biases.

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The Intracloud Lightning Fraction in the Contiguous United States

Monthly Weather Review ◽

10.1175/mwr-d-16-0426.1 ◽

2017 ◽

Vol 145 (11) ◽

pp. 4481-4499 ◽

Cited By ~ 24

Author(s):

Gina Medici ◽

Kenneth L. Cummins ◽

Daniel J. Cecil ◽

William J. Koshak ◽

Scott D. Rudlosky

Keyword(s):

United States ◽

Pacific Northwest ◽

Central California ◽

The Pacific ◽

Lightning Detection ◽

Maximum Period ◽

Total Lightning ◽

Imaging Sensor ◽

Optical Transient

This work addresses the long-term relative occurrence of cloud-to-ground (CG) and intracloud (IC; no attachment to ground) flashes for the contiguous United States (CONUS). It expands upon an earlier analysis by Boccippio et al. who employed 4-yr datasets provided by the U.S. National Lightning Detection Network (NLDN) and the Optical Transient Detector (OTD). Today, the duration of the NLDN historical dataset has more than tripled, and OTD data can be supplemented with data from the Lightning Imaging Sensor (LIS). This work is timely, given the launch of GOES-16, which includes the world’s first geostationary lightning mapper that will observe total lightning (IC and CG) over the Americas and adjacent ocean regions. Findings support earlier results indicating factor-of-10 variations in the IC:CG ratio throughout CONUS, with climatological IC fraction varying between 0.3 and greater than 0.9. The largest values are seen in the Pacific Northwest, central California, and where Colorado borders Kansas and Nebraska. An uncertainty analysis indicates that the large values in the northwest and central California are likely not due to measurement uncertainty. The high IC:CG ratio (>4) throughout much of Texas reported by Boccippio et al. is not supported by this longer-term climatology. There is no clear evidence of differences in IC fraction between land and coastal ocean. Lightning characteristics in six selected large regions show a consistent positive relationship between IC fraction and the percent of positive CG flashes, irrespective of lightning incidence (flash density), dominant season, or diurnal maximum period.

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Data Retrieval Algorithms for Validating the Optical Transient Detector and the Lightning Imaging Sensor

Journal of Atmospheric and Oceanic Technology ◽

10.1175/1520-0426(2000)017<0279:drafvt>2.0.co;2 ◽

2000 ◽

Vol 17 (3) ◽

pp. 279-297 ◽

Cited By ~ 4

Author(s):

W. J. Koshak ◽

R. J. Blakeslee ◽

J. C. Bailey

Keyword(s):

Data Retrieval ◽

Retrieval Algorithms ◽

Imaging Sensor ◽

Optical Transient

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Nitrogen oxides in the global upper troposphere: interpreting cloud-sliced NO<sub>2</sub> observations from the OMI satellite instrument

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-17017-2018 ◽

2018 ◽

Vol 18 (23) ◽

pp. 17017-17027 ◽

Cited By ~ 8

Author(s):

Eloise A. Marais ◽

Daniel J. Jacob ◽

Sungyeon Choi ◽

Joanna Joiner ◽

Maria Belmonte-Rivas ◽

...

Keyword(s):

Nitrogen Oxides ◽

Lightning Flash ◽

Ozone Monitoring Instrument ◽

Upper Troposphere ◽

Significant Difference ◽

Global Coverage ◽

The Tropics ◽

Imaging Sensor ◽

Lightning Nox ◽

Optical Transient

Abstract. Nitrogen oxides (NOx≡NO+NO2) in the upper troposphere (UT) have a large impact on global tropospheric ozone and OH (the main atmospheric oxidant). New cloud-sliced observations of UT NO2 at 450–280 hPa (∼6–9 km) from the Ozone Monitoring Instrument (OMI) produced by NASA and the Royal Netherlands Meteorological Institute (KNMI) provide global coverage to test our understanding of the factors controlling UT NOx. We find that these products offer useful information when averaged over coarse scales (20∘×32∘, seasonal), and that the NASA product is more consistent with aircraft observations of UT NO2. Correlation with Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) satellite observations of lightning flash frequencies suggests that lightning is the dominant source of NOx to the upper troposphere except for extratropical latitudes in winter. The NO2 background in the absence of lightning is 10–20 pptv. We infer a global mean NOx yield of 280±80 moles per lightning flash, with no significant difference between the tropics and midlatitudes, and a global lightning NOx source of 5.9±1.7 Tg N a−1. There is indication that the NOx yield per flash increases with lightning flash footprint and with flash energy.

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Brief Communication: An Electrifying Atmospheric River: Understanding the Thunderstorm Event in Santa Barbara County during March 2019

10.5194/nhess-2019-342 ◽

2019 ◽

Cited By ~ 1

Author(s):

Deanna Nash ◽

Leila M. V. Carvalho

Keyword(s):

Southern California ◽

Winter Season ◽

Tropical Rainfall Measuring Mission ◽

Winter Storm ◽

Santa Barbara ◽

Lightning Strikes ◽

Atmospheric River ◽

Massive Number ◽

Imaging Sensor ◽

Optical Transient

Abstract. On 5 March 2019 12 UTC, an Atmospheric River (AR) made landfall in Santa Barbara, CA and lasted approximately 30 hours. This AR was one of many that occurred during the winter season in Santa Barbara. However, during this AR, a massive number of lightning pulses were detected by Earth Networks Global Lightning Network (ENGLN) near and off the coast of Santa Barbara, CA. In the 24 hours following 6 March 2019 00 UTC, 14,416 lightning flashes occurred around southern California (140° W to 110° W and 20° N to 50° N). This far exceeded the climatological average number of lightning flashes recorded by the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) on the Tropical Rainfall Measuring Mission (TRMM). Between the years of 1995 and 2014, the TRMM LIS-OTD detected an average flash density of approximately 9.15 flashes per day in the same region around southern California. While the AR could be considered part of a typical winter storm in the area, the extraordinary amount of lightning strikes in the region was very anomalous. This combined thunderstorm and Atmospheric River event resulted in 36-hour precipitation totals in Santa Barbara to be approximately 77.6 mm, with a maximum rain rate of 16.5 mm h−1. This article describes the synoptic and mesoscale characteristics of this electrifying AR event.

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Global patterns of lightning properties derived by OTD and LIS

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-2715-2014 ◽

2014 ◽

Vol 14 (10) ◽

pp. 2715-2726 ◽

Cited By ~ 24

Author(s):

S. Beirle ◽

W. Koshak ◽

R. Blakeslee ◽

T. Wagner

Keyword(s):

Spatial Patterns ◽

Regional Differences ◽

Flash Duration ◽

Flash Rate ◽

The Mean ◽

Global Patterns ◽

The Tropics ◽

Imaging Sensor ◽

Lightning Nox ◽

Optical Transient

Abstract. The satellite instruments Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS) provide unique empirical data about the frequency of lightning flashes around the globe (OTD), and the tropics (LIS), which have been used before to compile a well-received global climatology of flash rate densities. Here we present a statistical analysis of various additional lightning properties derived from OTD / LIS, i.e., the number of so-called "events" and "groups" per flash, as well as the mean flash duration, footprint and radiance. These normalized quantities, which can be associated with the flash "strength", show consistent spatial patterns; most strikingly, oceanic flashes show higher values than continental flashes for all properties. Over land, regions with high (eastern US) and low (India) flash strength can be clearly identified. We discuss possible causes for and implications of the observed regional differences. Although a direct quantitative interpretation of the investigated flash properties is difficult, the observed spatial patterns provide valuable information for the interpretation and application of climatological flash rates. Due to the systematic regional variations of physical flash characteristics, viewing conditions, and/or measurement sensitivities, parametrizations of lightning NOx based on total flash rate densities alone are probably affected by regional biases.

Download Full-text