The Lightning Imaging Sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) effect... more The Lightning Imaging Sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) effectively reached its end of life on April 15, 2015 after 17+ years of observation. Given the wealth of information in the archived LIS lightning data, and growing use of optical observations of lightning from space throughout the world, it is still of importance to better understand LIS calibration and performance characteristics. In this work, we continue our efforts to quantify the optical characteristics of the LIS pixel array, and to further characterize the detection efficiency and location accuracy of LIS. The LIS pixel array was partitioned into four quadrants, each having its own signal amplifier and digital conversion hardware. In addition, the sensor optics resulted in a decreasing sensitivity with increasing displacement from the center of the array. These engineering limitations resulted in differences in the optical emissions detected across the pixel array. Our work to date ha...
We compared lightning data that was obtained using NASA’s Lightning Imaging Sensor (LIS) and the ... more We compared lightning data that was obtained using NASA’s Lightning Imaging Sensor (LIS) and the U.S. National Lightning Detection NetworkTM (NLDN) prior to and after a network-wide NLDN upgrade completed in August 2013. This work includes analysis from 5 days in March, 2013 before the upgrade and 11 days in September after the upgrade. A total of 3,804 NLDN cloud pulses and cloud-to-ground strokes within the LIS field-of-view, and an overall 25,070 LIS groups (which are the “optical equivalent” to cloud pulses and/or strokes in the NLDN reports) in 1,874 flashes from the LIS have been evaluated. Overall, the post-upgrade detection efficiencies of the NLDN relative to the LIS increased from 6.4% to 9.9% at the group level, and from 42.9% to 48.7% at the flash level. On the other hand, the detection efficiencies of the LIS relative to the NLDN decreased from 55.6% to 52.9% at the group level and from 75.6% to 68.3% at the flash level, which are mainly due to the enhanced cloud pulses...
The organization and structure of thunderstorms determines the extent and severity of their hazar... more The organization and structure of thunderstorms determines the extent and severity of their hazards to the general public and their consequences for the Earth system. Distinguishing vigorous convective regions that produce heavy rain and hail from adjacent regions of stratiform clouds or overhanging anvil clouds that produce light to no rainfall is valuable in operations and physical research. Cloud-type algorithms that partition convection from stratiform regions have been developed for space-based radar, passive microwave, and now Geostationary Operational Environmental Satellites (GOES) Advanced Baseline Imager (ABI) multispectral products. However, there are limitations for each of these products including temporal availability, spatial coverage, and the degree to which they based on cloud microphysics. We have developed a cloud-type algorithm for GOES Geostationary Lightning Mapper (GLM) observations that identifies convective/nonconvective regions in thunderstorms based on sig...
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The GOES‐16 Geostationary Lightning Mapper (GLM) detection efficiency (DE) is studied over
a full... more The GOES‐16 Geostationary Lightning Mapper (GLM) detection efficiency (DE) is studied over a full year (2018/19) in central Florida using the Kennedy Space Center Lightning Mapping Array (KSC LMA). Mean daily flash DE was 73.8%, and detection was highest during nighttime hours. GLM reported 86.5% of the LMA flashes that had coincident cloud‐to‐ground return strokes reported by the U.S. National Lightning Detection Network. Results also reveal that flash size and duration are critical parameters influencing GLM detection, regardless of the storm type, with 20–40% detection for small and short‐duration flashes and greater than 95% detection for very large and long‐duration flashes. These findings can be explained by examining the time‐evolution of cloud‐top optical emissions observed by the Lightning Imaging Sensor (LIS). Statistical simulations based on long‐term LIS group area observations indicate that about half of the above‐threshold light sources are smaller than a LIS pixel (~ 4 × 4 km) and are smallest during and just after an initial breakdown in IC flashes. This work also demonstrates that for sources smaller than a GLM pixel, the cloud‐top energy detection threshold for GLM is double that for LIS despite GLM's lower energy density threshold. Overall, these findings provide a framework for interpreting GLM performance under varying meteorological conditions, and help explain reports of low flash detection efficiency for storms associated with severe weather, as they typically exhibit high flash rates and resulting small and short‐duration flashes.
The Lightning Imaging Sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) effect... more The Lightning Imaging Sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) effectively reached its end of life on April 15, 2015 after 17+ years of observation. Given the wealth of information in the archived LIS lightning data, and growing use of optical observations of lightning from space throughout the world, it is still of importance to better understand LIS calibration and performance characteristics. In this work, we continue our efforts to quantify the optical characteristics of the LIS pixel array, and to further characterize the detection efficiency and location accuracy of LIS. The LIS pixel array was partitioned into four quadrants, each having its own signal amplifier and digital conversion hardware. In addition, the sensor optics resulted in a decreasing sensitivity with increasing displacement from the center of the array. These engineering limitations resulted in differences in the optical emissions detected across the pixel array. Our work to date ha...
We compared lightning data that was obtained using NASA’s Lightning Imaging Sensor (LIS) and the ... more We compared lightning data that was obtained using NASA’s Lightning Imaging Sensor (LIS) and the U.S. National Lightning Detection NetworkTM (NLDN) prior to and after a network-wide NLDN upgrade completed in August 2013. This work includes analysis from 5 days in March, 2013 before the upgrade and 11 days in September after the upgrade. A total of 3,804 NLDN cloud pulses and cloud-to-ground strokes within the LIS field-of-view, and an overall 25,070 LIS groups (which are the “optical equivalent” to cloud pulses and/or strokes in the NLDN reports) in 1,874 flashes from the LIS have been evaluated. Overall, the post-upgrade detection efficiencies of the NLDN relative to the LIS increased from 6.4% to 9.9% at the group level, and from 42.9% to 48.7% at the flash level. On the other hand, the detection efficiencies of the LIS relative to the NLDN decreased from 55.6% to 52.9% at the group level and from 75.6% to 68.3% at the flash level, which are mainly due to the enhanced cloud pulses...
The organization and structure of thunderstorms determines the extent and severity of their hazar... more The organization and structure of thunderstorms determines the extent and severity of their hazards to the general public and their consequences for the Earth system. Distinguishing vigorous convective regions that produce heavy rain and hail from adjacent regions of stratiform clouds or overhanging anvil clouds that produce light to no rainfall is valuable in operations and physical research. Cloud-type algorithms that partition convection from stratiform regions have been developed for space-based radar, passive microwave, and now Geostationary Operational Environmental Satellites (GOES) Advanced Baseline Imager (ABI) multispectral products. However, there are limitations for each of these products including temporal availability, spatial coverage, and the degree to which they based on cloud microphysics. We have developed a cloud-type algorithm for GOES Geostationary Lightning Mapper (GLM) observations that identifies convective/nonconvective regions in thunderstorms based on sig...
&... more &am…
The GOES‐16 Geostationary Lightning Mapper (GLM) detection efficiency (DE) is studied over
a full... more The GOES‐16 Geostationary Lightning Mapper (GLM) detection efficiency (DE) is studied over a full year (2018/19) in central Florida using the Kennedy Space Center Lightning Mapping Array (KSC LMA). Mean daily flash DE was 73.8%, and detection was highest during nighttime hours. GLM reported 86.5% of the LMA flashes that had coincident cloud‐to‐ground return strokes reported by the U.S. National Lightning Detection Network. Results also reveal that flash size and duration are critical parameters influencing GLM detection, regardless of the storm type, with 20–40% detection for small and short‐duration flashes and greater than 95% detection for very large and long‐duration flashes. These findings can be explained by examining the time‐evolution of cloud‐top optical emissions observed by the Lightning Imaging Sensor (LIS). Statistical simulations based on long‐term LIS group area observations indicate that about half of the above‐threshold light sources are smaller than a LIS pixel (~ 4 × 4 km) and are smallest during and just after an initial breakdown in IC flashes. This work also demonstrates that for sources smaller than a GLM pixel, the cloud‐top energy detection threshold for GLM is double that for LIS despite GLM's lower energy density threshold. Overall, these findings provide a framework for interpreting GLM performance under varying meteorological conditions, and help explain reports of low flash detection efficiency for storms associated with severe weather, as they typically exhibit high flash rates and resulting small and short‐duration flashes.
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a full year (2018/19) in central Florida using the Kennedy Space Center Lightning Mapping Array (KSC
LMA). Mean daily flash DE was 73.8%, and detection was highest during nighttime hours. GLM reported
86.5% of the LMA flashes that had coincident cloud‐to‐ground return strokes reported by the U.S. National
Lightning Detection Network. Results also reveal that flash size and duration are critical parameters
influencing GLM detection, regardless of the storm type, with 20–40% detection for small and short‐duration
flashes and greater than 95% detection for very large and long‐duration flashes.
These findings can be explained by examining the time‐evolution of cloud‐top optical emissions observed by
the Lightning Imaging Sensor (LIS). Statistical simulations based on long‐term LIS group area observations
indicate that about half of the above‐threshold light sources are smaller than a LIS pixel (~ 4 × 4 km)
and are smallest during and just after an initial breakdown in IC flashes. This work also demonstrates that
for sources smaller than a GLM pixel, the cloud‐top energy detection threshold for GLM is double that for
LIS despite GLM's lower energy density threshold. Overall, these findings provide a framework for
interpreting GLM performance under varying meteorological conditions, and help explain reports of low
flash detection efficiency for storms associated with severe weather, as they typically exhibit high flash rates
and resulting small and short‐duration flashes.
a full year (2018/19) in central Florida using the Kennedy Space Center Lightning Mapping Array (KSC
LMA). Mean daily flash DE was 73.8%, and detection was highest during nighttime hours. GLM reported
86.5% of the LMA flashes that had coincident cloud‐to‐ground return strokes reported by the U.S. National
Lightning Detection Network. Results also reveal that flash size and duration are critical parameters
influencing GLM detection, regardless of the storm type, with 20–40% detection for small and short‐duration
flashes and greater than 95% detection for very large and long‐duration flashes.
These findings can be explained by examining the time‐evolution of cloud‐top optical emissions observed by
the Lightning Imaging Sensor (LIS). Statistical simulations based on long‐term LIS group area observations
indicate that about half of the above‐threshold light sources are smaller than a LIS pixel (~ 4 × 4 km)
and are smallest during and just after an initial breakdown in IC flashes. This work also demonstrates that
for sources smaller than a GLM pixel, the cloud‐top energy detection threshold for GLM is double that for
LIS despite GLM's lower energy density threshold. Overall, these findings provide a framework for
interpreting GLM performance under varying meteorological conditions, and help explain reports of low
flash detection efficiency for storms associated with severe weather, as they typically exhibit high flash rates
and resulting small and short‐duration flashes.