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Abstract Bangkok, Thailand is a tropical Asian megacity with high aerosol concentrations and frequent thunderstorm activity. This investigation examines the covariation between thermodynamics, aerosols, and thunderstorms, using lightning stroke counts as a measure of intensity, for a five-year period (2016–2020). The investigation incorporates data from the aerosol robotic network (AERONET), ERA-5 reanalysis, ground-based air quality stations, and total lighting data from Vaisala Inc.’s GLD360 network to examine the aerosol-thermodynamic interrelationships within thunderstorm initiation environments. Results indicate that aerosol impacts on thunderstorms are robust and, when examined in concert with instability, can augment lightning. Thermodynamic instability is also positively correlated with stroke counts in thunderstorms. Particulate matter greater than 10 µg m-3(PM10) concentration is significantly higher in thunderstorms containing more than 100 strokes, supporting the potential role of aerosols in promoting the non-inductive charge process. The emergence of a “boomerang” or threshold effect is also evident as aerosol optical depth (AOD) increases. Evidence suggests increasing AOD initially promotes, then limits, instability and thunderstorm intensity. Finally, there exists a positive relationship between aerosol concentration and particle size in thunderstorm initiation environments.
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Developing an urban thunderstorm climatology for the Bangkok Metropolitan Region
This investigation builds upon and extends prior lightning research in the Bangkok Metropolitan Region (BMR) through the reconstruction of thunderstorm distribution, utilizing a novel lightning tracking algorithm. Five years (2016–2020) of lightning stroke data from the Global Lightning Dataset (GLD360) were used to identify 52 608 thunderstorms. Optimized hotspot analyses, track densities, and analyses of thunderstorms with respect to winds, landcover, and seasons were performed. Our findings suggest that significant modification of thunderstorm distribution within the region was due to urban landcover impacts on the local environment. Thunderstorm intensity, as measured by stroke counts and track length, also appeared to be sensitive to the urban environment. The thunderstorm distribution also highlighted areas prone to hazards such as flash flooding. By visualizing thunderstorms grouped by winds, thunderstorm initiation hotspots and track density corridors were identified. These corridors of augmented thunderstorm production tended to occur during specific months given the seasonal monsoon wind regime occurring across the BMR. As urbanization within the BMR continues, geospatial assessment of thunderstorms is important to inform forecast meteorologists, urban planners, government officials, and others who play a critical role in developing strategies, policies and insfrastructure that could mitigate thunderstorm impacts.
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- Award ID(s):
- 2104299
- PAR ID:
- 10544146
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Singapore Journal of Tropical Geography
- Volume:
- 45
- Issue:
- 3
- ISSN:
- 0129-7619
- Format(s):
- Medium: X Size: p. 498-514
- Size(s):
- p. 498-514
- Sponsoring Org:
- National Science Foundation
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