@Article{BourscheidtPintNacc:2016:DeAn19,
author = "Bourscheidt, Vandoir and Pinto J{\'u}nior, Osmar and Naccarato,
Kleber Pinheiro",
affiliation = "{Universidade Federal de S{\~a}o Carlos (UFSCAR)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)}",
title = "The effects of Sao Paulo urban heat island on lightning activity:
Decadal analysis (1999-2009)",
journal = "Journal of Geophysical Research: Atmospheres",
year = "2016",
volume = "121",
number = "9",
pages = "4429--4442",
month = "May",
keywords = "lightning activity, Sao Paulo, temperature contrast, thunderstorm
initiation, urban heat islands.",
abstract = "Eleven years of lightning data from the Brazilian Integrated
National Lightning Detection Network were used to analyze the
effects of the urban heat island (UHI) of Sao Paulo on lightning
activity, extending the investigation of previous works.
Cloud-To-ground lightning data were analyzed in both spatial and
temporal perspectives, using different approaches: flash density,
flash rate, thunderstorm hours (TH), and the cell initiation
technique (CIT), which aims to identify the onset of
thunderstorms. Land surface temperature (LST) from MODIS (Moderate
Resolution Imaging Spectroradiometer) was used to analyze the UHI
evolution over the years. MODIS data were validated using ground
stations, distributed within the urban area. Different time
intervals (seasonal and intraday) were used in an attempt to
separate local convective systems from synoptic-scale events. The
results indicate significant effects of the UHI (using LST) on THs
and CIT. The CIT showed a nearly ring pattern, especially during
the afternoon (14:00-18:00 LT) of summer months, reinforcing
temperature contrast as a condition for storm initiation. The
results also suggest an amplification of the UHI effects on
thunderstorm activity by local factors (sea and country breeze,
synoptic events, and terrain). Higher flash rates were also
observed throughout the urban region, which influences the
lightning density. Temporal analysis indicates that minimum
temperature and lightning activity increase in wintertime. In
summary, the results agree with previous studies about the UHI and
indicate its importance on lightning occurrence, especially by
increasing the temperature contrast and the instability in these
regions.",
doi = "10.1002/2016JD024782",
url = "http://dx.doi.org/10.1002/2016JD024782",
issn = "2169-8996 and 2169-897X",
language = "en",
targetfile = "bourscheidt_theeffects.pdf",
urlaccessdate = "27 abr. 2024"
}