Banca de QUALIFICAÇÃO: IRIS LAYANNE NOBRE FRANCA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : IRIS LAYANNE NOBRE FRANCA
DATE: 09/09/2021
TIME: 09:30
LOCAL: VIDEOCONFERÊNCIA
TITLE:

EFFECT OF CLIMATE VARIABILITY ON LOW RESERVOIR LEVELS IN THE
SÃO FRANCISCO RIO HYDROGRAPHIC BASIN

KEY WORDS:

Drought, Mann-Kendall, Ripples, Trends.

PAGES: 73
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUMMARY:

The number of occurrences of extreme precipitation events has increased over
the last few years, occurring, in some cases, with greater intensity and duration, thus
favoring natural disasters such as severe droughts. Therefore, the expansion of
knowledge about the quantity/frequency of rain that falls in a region is fundamental for
the strategic planning of local and regional water resources. In this context, this research
aims to analyze the level of the main reservoirs of the four sub-basins that make up the
BHSF, identifying rainfall events, particularly drought, and their possible climatic
causes. The study was carried out with precipitation and quota data from four
representative stations for each variable, obtained from the National Water Agency
(ANA) for the period 1968 to 2020. Extreme drought events were classified and
characterized by the standardized precipitation index (SPI), in addition to identifying
years of greater rainfall deficits. The Mann-Kendall test was used to detect climate
trends in rainfall series in the four sub-regions of the BHSF. Ondaletas analysis was
used with the intention of verifying extreme rainfall cycles and their causes through the
temporal scales observed in the precipitation series of the BHSF sub-regions.
Preliminary results show that all sub-regions have higher occurrences of droughts than
rains, however, extreme drought events are infrequent, whereas mild drought events
were more recurrent. The years characterized as almost normal were the ones with the
highest number in the four sub-regions, however, in all of them, the episodes of mild
drought had significant percentages. To identify possible climatic causes, Wavelet
Analysis was used. Of the four sub-regions, three of them show a downward trend in
rainfall and quota, while only one shows an increase trend, highlighting possible
changes in the sub-regions' reservoir levels. It was found that the seasonal and
interannual scales dominated, associated with the persistent El Niño Southern
Oscillation sign (7 years). With information on the influence of temporal cycles on
precipitation in the BHSF sub-regions, it is possible to visualize the impact of climatic
phenomena on the water reserve of the Basin.

BANKING MEMBERS:
Presidente - 1772619 - DJANE FONSECA DA SILVA
Externo ao Programa - 2570329 - HENRIQUE RAVI ROCHA DE CARVALHO ALMEIDA
Externo à Instituição - LINCOLN ELOI DE ARAÚJO - UFPB
Interna - 1653612 - MARIA LUCIENE DIAS DE MELO