Automatic classification of NOAA GVI data Set
Sunpyo Hong, Akira Inoue, Takashi Tada, Kiyonari Fukue
Haruhisa Shimoda,Toshibumi Sakata
Tokai University Research and Information Center
2-28-4 Tomigaya, Shibuya-ku, Tokyo 151, Japan
Abstract
Recently, global mentoring of ecological environment has come a serious matter because of growing industrial human activities. Especially, monitoring, of vegetation, such as tropical forest, has been focused Satellite Remote Sensing technology has the possibility of global monitoring on ecological adaptation.
In this research, a method of global vegetation monitoring using GVI (Global Vegetation Index) data set made by NOAA (National Oceanic and Atmospheric Administration) is proposed. At first, clouds removing and illumination correction are performed on original data. and temporal / annual change of NDVI is extracted. Additionally, vegetation map is automatically generated by the adoption of automatic classification method for multi-temporal image data.
Introduction
There exist many studies of global vegetation monitoring using the same data set, but most of them use NDVI (normalized difference vegetation index) as only one feature. However from our past experiment, NDVI can provide only limited information for vegetation monitoring. Further, NDVI can not perfectly remove influence of illumination variation as well as atmospheric effects. Here, we propose a method utilizing radiometric correction and original channel 1, 2 and 5 data for vegetation monitoring.
Proposed Method
The following conditions are necessary for Remote Sensing data, which can be used to global vegetation monitoring.
- wide observation coverage
- high repetitive observation
- adequate spectral range for extracting vegetation
Above conditions are not satisfied in the case of most of earth observation satellite such as Landsat, SPOT MOS1, nor the other geostationary orbit satellites. In the case of GVI data set, these conditions are satisfied. GVI data set is composed of 4 channel image data derived from Ch 1, 2, 4, 5 of AVHRR (Advanced Very High Resolution Radiometer), and 3 channel auxiliary data which are solar zenith angle, scan angle and NDVI data.
The data used in the experiments are as follows.
| Target sensor |
: |
NOAA AVHRR |
| Target area |
: |
entire of earth (55 S - 75 N) |
| Date of data |
: |
1985 Apr. - 1989 Dec. |
| Size of data |
: |
1024 x 2048 pixels |
| Coordinate |
: |
polar stereo |
| Used data |
: |
AVHRR Ch 1, Ch 2, Ch 5 and solar zenith angle |
The amount of the above data is about 400 Mbyte per one year, so the total amount is about 2 Gbyte, and Ch 4 data was not used because of high correlation to Ch. 5
