Banca de DEFESA: GABRIELA ISABEL LIMOEIRO ALVES NASCIMENTO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : GABRIELA ISABEL LIMOEIRO ALVES NASCIMENTO
DATE: 20/12/2023
TIME: 09:00
LOCAL: meet.google.com/psk-bdgd-vjb
TITLE:

Statistical and geostatistical approach to precipitation rainfall in Sertão do Pajeú, Pernambuco/Brazil

KEY WORDS:

Rainfall; Interpolation; Geostatistics; Cross validation; Pajeú

PAGES: 77
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUMMARY:

Changes in the behavior of rainfall evolution affected the hydrological cycle and consequently water resources. In cases of extreme climate change, the impact is related to changes in water resources, the occurrence of more severe and frequent floods and droughts. In this sense, studying the impacts of climate change on water resources is strategic for the elaboration, implementation and strengthening of public policies involved in the management of water resources. The present research aimed to characterize the rainfall economy in Sertão do Pajeú - PE, as well as provide subsidies for public policies aimed at water scarcity through the study and analysis of space/time. To this end, information was collected from rainfall levels in the region and surrounding areas, corresponding to the period 1993 and 2022, and statistical and geostatistical methodologies were used. data were initially processed using the regression method to complement missing data. Then, a series was checked for trend, consistency and disruption of information. In all cases, the results of the tests showed that there was no statistically significant trend, the consistency of the data was validated and the ruptures identified were not significant at the 5% level. Therefore, we approached the statistical characterization of the Pajeú variation where the climatological normal was 80.62mm. Furthermore, the classification of years was carried out using the quantile technique. The results were overwhelming, showing that some years classified as Very Dry or Dry (1993, 1998, 2015 and 2016) coincided with the occurrence of ENSO events. In relation to the geostatistical analysis, adjustments were made to the spherical, exponential and gaussian models. The models were selected using the cross-validation method. All models were well adjusted, however the gaussian model showed greater goodness of fit R2 = 90.5%. Therefore, the gaussian model proved to be more suitable for adjusting the precipitation in Sertão do Pajeú. Finally, simple spatial interpolation techniques (Thiessen, Spline and IDW), the Spline method, showed better fit and accuracy in interpolation. In relation to the other techniques, kriging considering the
parameters of the gaussian model presented better results in terms of both adjustment (R2 = 95.1%) and accuracy (lower error measurements). Thus, it is possible to conclude that the methodology used to study the average annual rainfall in the Pajeú microregion allowed satisfactory results to be obtained in the assessment of its spatial variability, being able to determine and express the spatial continuity of rainfall and support policies public issues related to water issues in the region.

COMMITTEE MEMBERS:
Externo à Instituição - MAURÍCIO COSTA GOLFARD - UPE
Interno - LUCIAN BOGDAN BEJAN
Externo à Instituição - MANOEL RIVELINO GOMES DE OLIVEIRA - UFBA
Presidente - MOACYR CUNHA FILHO
Externa à Instituição - ROSANGELA ESTEVAO ALVES FALCAO - UPE