Evaluating the Relationship Between Lightning and the Large-Scale Environment and its Use for Lightning Prediction in Global Climate Models Academic Article uri icon

abstract

  • AbstractThe objective of this study is to determine the relationship between lightning observed by the Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor (LIS) and seven largescale environmental variables obtained from the 3hourly ModernEra Retrospective analysis for Research and Application version 2 (MERRA2) reanalysis in the tropics and subtropics. The largescale environmental variables used are: convective available potential energy (CAPE), normalized CAPE (nCAPE), lifting condensation level (LCL), column saturation fraction (r), 700hPa omega, lowlevel wind shear (LS) from 900 to 700hPa, and deep wind shear (DS) from 900 to 300hPa. All environmental variables show a significant shift toward larger values when lightning is present except for shear. DS decreases when lightning is present, while LS shows little mean change. However, strong geographical differences exist in the relationship between the environmental variables and lightning occurrence, particularly between land and ocean and the tropics and subtropics. Using a logistic regression, a lightning parameterization for global climate models (GCMs) is created using the above environmental variables as predictors while also adding geographic indicators (coast, slope, and latitude) and terms representing interactions between the predictors. The logistic regression predicts lightning occurrence accurately up to 86% of the time and is further applied to MERRA2. While there are regions of overprediction and underprediction, the lightning parameterization performance shows promising potential for use in GCMs.

published proceedings

  • JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES

altmetric score

  • 2.7

author list (cited authors)

  • Etten-Bohm, M., Yang, J., Schumacher, C., & Jun, M.

citation count

  • 9

publication date

  • March 2021