Global Land Cover Classification by NOAA AVHRR data
Takayuki Odajima, Koji Kajiwara, Ryutaro Tateishi
Remote Sensing and Image Research Center, Chiba University
1-33, Yayoi-Cho, Chiba City, Chiba, 260 Japan
Abstract
For the purpose of global scale and cover classification, cluster analysis was performed two times to monthly global vegetation index (GVI) data. First cluster analysis was applied separately to the north hemisphere and south hemisphere. N both hemispheres, 31 clusters were obtained form 40 initial clusters. Second cluster analysis was applied to both hemispheres with the data by using 62 centroids of resultants clusters of the first cluster analysis as initial clusters. 44 clusters were obtained by the second cluster analysis. As a result, land cover map of the world with 13 types was produced fro the viewpoint of seasonal vegetation dynamics.
Introduction
Recently, the problems of the earth environment such as deforestation, desertification, destruction of ozone layer … and so on , have been the object of public interest, and many papers have been reported about that. NOAA data especially GVI data is the great tools for monitoring global vegetation distribution. Many phonological studies have been achieved by using NOAA data (justice et al., 1986; Townsend et al., 1989 etc)
Authors have studies by using NOAA data about classifying and monitoring the land cover in eh Asian Region (Tateishi et. al 1990). Since the NOAA data has the potential for analyzing the larger region, the study area was extended from the Asian region to eh whole earth and classified global and covers by cluster analysis of NOAA AVHRR data in 1987.
Data
The following data were used in this study
- NOAA AVHRR weekly channel data (Ch1, Ch2) in 1987
- NOAA weekly GVI data in 1987
- Global DEM data (ETOPO 5)
- Wilson's global land cover data
- Philip's great world atlas
- Atlas zur biogeographic.
Since the area of this study is the whole earth the plate Carree projection data was chosen. The advantage of this projection is the easiness of registration with other image data. The characteristics of data 1) and 2) are well described in NOAA POLAR ORBITER DATA USERS GUIDE (SDSD, 1986) and GLOBAL VEGETATION INDEX USERS GUIDE (SD SD 1986)_____
TEXT NOT CLEAR IN HARD COPY_____ Tateishi et al 1990. The data 4), 5) and 60 were used for checking the results of the cluster analysis.
