Banca de DEFESA: SAMUEL AMORIM SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : SAMUEL AMORIM SILVA
DATE: 27/02/2026
TIME: 14:00
LOCAL: Google Meet
TITLE:

Assessment of Lightning in Extreme Hourly Precipitation Events in Ceará

KEY WORDS:

Nowcasting; Lightning Jump; Orography; Disasters; Remote Sensing.

PAGES: 124
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Meteorologia
SPECIALTY: Sensoriamento Remoto da Atmosfera
SUMMARY:

The occurrence of extreme precipitation events in the Brazilian semi-arid region, aggravated by socio-environmental vulnerability, acts as a trigger for hydrometeorological disasters that lack effective short-term warning systems. In this context, this research investigates the dynamic mechanisms and the spatiotemporal distribution of atmospheric electrical activity in Ceará, aiming to validate the use of lightning data as a nowcasting tool. The study integrates remote sensing data from the GLM sensor (GOES-16 satellite) and surface rainfall records (INMET, FUNCEME, CEMADEN) between 2018 and 2024, using the 99th percentile statistical threshold (32.26 mm/h) to characterize hourly extreme precipitation events in the state. Data analysis reveals a dichotomy where precipitation frequency predominates on the coast, whereas the precipitation rate inland exceeds 40 mm/h. Results evidence that the spatial distribution of lightning is strictly modulated by the orographic forcing of the Ibiapaba and Araripe mountains, presenting a seasonal hysteresis marked by the predominance of mixed-phase microphysical processes from January to March, in contrast to the warm cloud efficiency observed on the coast. A case study of a Mesoscale Convective System demonstrated the efficacy of the Lightning Jump, with an increase exceeding 150% in flash rate, preceding the surface hydrological response with a 20-minute lead time, concludes that, although the geography of disasters is governed by urban vulnerability, monitoring electrification offers a temporal window for the early issuance of flash flood warnings.

COMMITTEE MEMBERS:
Presidente - ***.072.934-** - WEBER ANDRADE GONCALVES - UFCG
Interno - 1280761 - CRISTIANO PRESTRELO DE OLIVEIRA
Externo à Instituição - EVANDRO MOIMAZ ANSELMO - FUNCEME
Externo à Instituição - ENRIQUE VIEIRA MATTOS - UNIFEI