Monday, 8 January 2018
Exhibit Hall 3 (ACC) (Austin, Texas)
The ionosphere consists of multiple discrete layers in which ionized particles exist in varying abundance. Previous studies used model simulations to show that increased lightning activity led to decreased electron density (Ne) within the D-layer of the ionosphere during intense, electrified storms. Ground-based GPS observations also suggest that the enhanced convective activity corresponds well with regions of enhanced total electron content (TEC) fluctuation. GPS radio occultation (RO) observations from the Constellation Observation System for Meteorology, Ionosphere and Climate (COSMIC) offers measurement of electron density profiles on a global scale. In this paper, GPS RO observations are collocated with observations from the Tropical Rainfall Measurement Mission (TRMM) in order to identify the Ne profiles in the vicinity of intense thunderstorms, identified by the TRMM lightning imaging sensor (LIS), and electrified shower clouds, identified by the TRMM precipitation radar (PR) and microwave imager (TMI). The COSMIC RO electron density anomalies over lightning hotspots in central Africa, northern South America and the Caribbean Sea were derived. Preliminary analysis shows a regional difference in ion density anomalies near the storms with and without a lightning flash. Over central Africa, the ion density anomaly increases by 2.6x105 e cm-3 near the storms with detected lightning flashes which is more than twice the anomaly of non-lighting storms above the regional mean, with a peak anomaly occurring within the F-region at 300-400 km level. This anomaly is most pronounced in the convection dominant region of central Africa and northern South America. However, The Ne anomaly over storm with lightning is less pronounced over the Pacific warmpool. These findings suggest that intense lightning storms could have a significant impact on the ion density in the F-region.
- Indicates paper has been withdrawn from meeting
- Indicates an Award Winner