Banca de DEFESA: HELDER JOSÉ FARIAS DA SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : HELDER JOSÉ FARIAS DA SILVA
DATA : 28/02/2019
HORA: 14:00
LOCAL: Anfiteatro B do CCET
TÍTULO:

Analysis of the effects of deforestation on evapotranspiration and cloud microphysics using remote sensing data in the Amazon.

PALAVRAS-CHAVES:

MOD16, TRMM, Logistic Regression, Biosphere,

PÁGINAS: 100
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
SUBÁREA: Meteorologia
ESPECIALIDADE: Sensoriamento Remoto da Atmosfera
RESUMO:

The objective of this research was to analyze the microphysical parameters of the cloud and the
spatial / temporal dynamics of the evapotranspiration (ET) inserted in the Brazilian Amazon region,
based on spectral data extracted from orbital sensors. In order to generate comparative statistics of
these components in forest and non-forest regions of the Brazilian Amazon considering the current
level of deforestation. The study area comprised the state of Rondônia, Brazil. As a methodology,
the analyzes in the ET fields were first carried out. Where the study area was sub-divided into
homogeneous regions of ET using the statistical technique of cluster analysis. Additionally, we
sought to analyze the use of a logistic regression model to create deforestation maps in Amazonia
based on ET fields. Orbital ET data and land cover type from the MOD16 product and the Amazon
Forest Satellite Monitoring Project - PRODES, respectively, were used, considering monthly data
from the period 2000 to 2014. For the analysis of the microphysical parameters the data were
extracted from the Microwave Imager - TMI and Precipitation Radar - PR sensors of the 2A -
CLIM and 2A25 products, respectively. From the TMI, the parameters considered were: Rain Water
Path - RWP, Cloud Water Path - IWP, Convective Precipitation - CP, Surface Precipitation - SP and
Frozen Precipitation - FP, the parameters of 2A25 were: Freezing Height - FH and Rain Type - RT.
Relay data from the Shuttle Radar Topographic Mission - SRTM were used to complement the
analyzes in order to verify the influence of the topography with the microphysical parameters and,
thus, to consider a lifting threshold for the comparative analyzes to avoid the bias arising from this
variable. Afterwards, all statistical calculations and tests were performed, as well as the construction
of histograms, charts and comparative tables using the statistical program R. The results showed
that in relation to ET, according to the clustering analysis, that for the study area three
homogeneous sub-regions were sufficient to represent the ET variability to which they were
obtained considering, mainly, the intensity and seasonal pattern of this process . When the impacts
after changing from a forest area to deforested, the analyzes indicated that ET of deforested areas
decreases by an average of 28% in the dry season and increases ~ 4% in the rainy season. The
differences observed in the rainy season were not significant at 5% significance according to
Student's T test. Unlike the dry season, which presented statistical significance (p-value <0.05). In
general, the results suggest that MOD16 data can provide a satisfactory representation of the change
from ET to large areas of the Brazilian Amazon. Logistic regression analysis showed that the spatial
pattern of deforestation can be identified by biophysical factors such as ET with 87% accuracy, as
long as the average environmental conditions of the environment are maintained, showing a
promising variable to identify future trends in the deforestation in tropical regions. Regarding the
analyzes of the microphysical parameters of cloud, the results show that, in general, the local relief
influences in the microphysical parameters being more pronounced from 721 meters of altitude. Our
analyzes also indicated that the level of local deforestation produced significant increases in the
RWP and IWP parameters of 11 and 13% (p-value <0.05), respectively, and reductions for CP, SP
and FP parameters ranging from 7.9, at 9.2% (p-value<0.05). Changes to FH and TP were not
statistically significant but slight increase for FH and higher frequency of convective rainfall in
deforested areas were observed. This suggests that the microphysical structure of the cloud presents
with distinct characteristics when related to forest and deforested areas.

MEMBROS DA BANCA:
Presidente - 1164414 - WEBER ANDRADE GONCALVES
Interno - 2086472 - BERGSON GUEDES BEZERRA
Interno - 1280761 - CRISTIANO PRESTRELO DE OLIVEIRA
Externo à Instituição - HELBER BARROS GOMES - UFAL
Externo à Instituição - MADSON TAVARES SILVA - UFCG