The Utility of Next Generation GOES Satellite Measurement Techniques for Assessing Lightning Initiation, Intensity and Charge Structure

The upcoming launch of GOES-R is a milestone in satellite detection of convection initiation and mechanics. The ability to measure temperature changes on a five minute to 30 second time scale allows for assessments of updraft strength and buoyancy which previous GOES satellites could not provide. The GOES-R Advanced Baseline Imager (ABI) also offers 16 spectral bands (compared to the five currently available on GOES-13). The addition of spectral channels will allow for new collection techniques to resolve cloud microphysical and kinematic characteristics that were not previously available. While several studies explore the relationship between lightning characteristics and radar, few examine the utility of satellite data due to the few capabilities of the current generation. This study will have two main components: (1) to explore next generation satellite techniques to help explain lightning characteristics, including initiation, intensity and intra-cloud to cloud to ground ratios, and (2) to use Super Rapid Scan Operations (SRSOR) data are used over several case studies in the United States to examine the utility of increased temporal resolution (1-min versus 15-min) when examining kinematic fields near convective storms.

For the first component, the Meteosat Second Generation (MSG), which offers 12 spectral channels will be gathered for convictive storms occurring over the CHUVA Experiment domain as select deep convective cases are studies over Sau Paulo, Brazil. Although our results for this component are preliminary, the goal is to increase our understanding of ABI-like data in advance of GOES-R, in combination with lightning mapping array and dual-polarimetric radar data. The second project component is more mature, and involves use of SRSOR data as they provide a unique opportunity for high temporal scale divergence and vorticity mesoscale atmospheric motion vector analysis and provides similar information of updraft intensity when compared to lightning jumps. A sample case study over Colorado exhibited the divergence jump behavior 15 minutes before an elevated tornado vortex signature was observed. Use of SRSOR brightness temperatures to profile atmospheric CAPE can also provide layer acceleration data in the pre-lightning initiation phase. For both study components, multiple bands in the pre-lightning initiation phase provide important nowcasting information on the microphysical structure and growth of convection. The satellite information examined in this presentation can be combined with radar and numerical weather prediction data to form lightning initiation and intensity nowcasting products. The utility of these techniques are explored with several select case studies on the current generation to benefit scientists and forecasters at the launch of GOES-R through enhanced algorithms that provide short-term predictions of lightning.