Análise da interferência de nuvens na classificação de séries temporais MODIS-NDVI na região da Amazônia, municícpio de Capixaba, Acre

Item

Título
Análise da interferência de nuvens na classificação de séries temporais MODIS-NDVI na região da Amazônia, municícpio de Capixaba, Acre
Sociedade & Natureza
Instituto Federal de Brasília
Universidade de Brasília
Description
Universidade de Brasília
Autor
Cristiane Batista Salgado
Osmar Abílio de Carvalho Junior
Roberto Arnaldo Trancoso Gomes
Renato Fontes Guimarães
Assunto
Amazônia
cobertura de nuvem
series temporais
Abstract
This research aimed to analyze MODIS-NDVI time series classifications, with three different algorithms, seeking to identify the ideal amount of images for studies in environments with high cloudiness rates. The spatial cut used for the study was the municipality of Capixaba, located in the state of Acre in the Amazon region. For each NDVI image, a cloud mask was constructed. This mask allowed to organize the temporal cube by cloud coverage quantity. Thus, the impact of eliminating high cloud images for the series classification was tested. At each cut, the temporal cube was redone, evaluating results for a new set of bands. For the accuracy analysis, the Kappa coefficient was adopted. A total of 84 classifications were made.  Three classification algorithms (Minimum Distance, Spectral Angle Mapper and Spectral Correlation Mapper) and 4 different interactions between classes and samples were tested. Over the period analyzed, approximately 80% of images showed cloud cover above 90%. The tests showed that the removal of the images with cloud increased the quality of the classification, and the best results were found in small cubes (10 to 35 images) and with low cloud cover (0 to ~ 6%). The Minimum Distance algorithm presented the lowest coefficient of variation, showing a lower sensitivity to the presence of clouds.
volume
31
Date
2019
título curto
Universidade de Brasília
Língua
pt
doi
10.14393/SN-v31-2019-47062
issn
1982-4513
Rights
Copyright (c) 2019 Cristiane Batista Salgado, Osmar Abílio de Carvalho Junior, Roberto Arnaldo Trancoso Gomes, Renato Fontes Guimarães
Coleções
SOCIEDADE&NATUREZA