LDAR II Operation, Evaluation, and Analyses in the Houston Environmental Aerosol Thunderstorm (HEAT) Project

 

Abstract

We propose a three-year period of support for the operation, evaluation and analysis of a twelve-station Lightning Detection and Ranging (LDAR II) total lightning detection network around Houston, Texas. The purchase of the equipment for the twelve-station network is funded by the National Science Foundation under a Major Research Initiative (MRI) one-year grant NSF ATM-0321052 (September 2003-2004). The initial installations are beginning (June 2004) in the summer of 2004 and will continue into the fall with operation of the network planned as soon as possible. A high cloud-to-ground lightning density anomaly has been previously identified over Houston, which has raised a number of scientific questions. We therefore propose to characterize the total lightning occurring over Houston and the surrounding areas using the LDAR II network and the National Lightning Detection Network (NLDN). The combination of data from the LDAR II and the NLDN will allow us to determine 1) the location and amplitude of the first lightning flash produced by a radar cell, 2) cloud flash rates, 3) cloud-to-ground flash rates, 4) the evolution of cloud/CG flash ratios, 5) the geometric extent of cloud discharge channels, 6) the initiation points of cloud and CG flashes, 7) the altitude from which the primary charge is lowered, 8) the area and volume in which charge is altered by lightning, 9) the polarity of CG strokes, 10) estimates of the peak currents in CG strokes, and 11) measurements of the multiplicity of strokes in CG flashes in the thunderstorms over Houston. All data will be part of the larger project, referred to as the Houston Environmental Aerosol Thunderstorm  project that will occur in 2005 and 2006.