EES N33 30° Table 1 Data used in this study
; Sn
Data Path -Row Das of Remarks
Ayla fa Acquisition
Landsat TM 112-37 1990.9.21 Before damage
Landsat TM 112-37 1992 521 Afier damage
991.10. ly after
Aeıtal photograph 1991.10.7 | Immedately after damage
Scale: About 1to30000
56km Approx.
were effective to extract the damaged areas. A method to
extract the damaged areas using Landsat TM data acquired
before and after the damage, and the results which evalu-
ated the extracted output using aerial photographs and data
on the damage surveyed by a Local Development Office
are described in this paper.
2. TEST SITE AND DATA USED
N33° 0°
[e————— 35km Approx. — — —— > vn.
E130°45° E131^ 7^30
1 west of Forests in Ohita Prefecture, a region of north Kyushu suf-
antations Fig. 2. Outlines of the test site fered big damages from the typhoons and an area under the
after the
group of Landsapa TM. data Landsat-TM. dera control of Hida Ee DENN
| Office,a branch of Ohita Prefectural
ely after Before the typhoons 1990.9.21 After the typhoons 1992.5.21 Ke |
it and no Office selected as a test site. Fig. 2
ue to tne shows the outlines of the test site.
band 5,7 Ceameïric correction C eormetric calTection The area of the test site is about
ted by a 35km east and west by 56km south
TM data and north ,and it includes 6
e. It was Generation of a registered image of bands 1~5,7 and VI of two temporal data munincipalities. Table 1 shows data
region. used in this study.Landsat TM data
covering the test site before and af-
| Selection of typical points for heavy ,slight and no damage using aerial photographs| ter the damage were searched and
two Landsat TM data shown in
Table 1 were available for the
Examination of change characteristics of bands 1~5,7 and VI due to the damage study.Data observed at a same sea-
son were not available. Aerial pho-
tographs were acquired by request
Generation of a registered image of bands 5,7 and VI of two temporal data
of Ohita Prefectural Office imme-
diately after the damage ,and taken
E f Rood assit at an altitude of 4400m ,therefore
xtraction of damaged areas by a maximum likelihood classification
2 y those scale are about 1 to 30000.
The aerial photographs covering a
Evaluation of damaged areas extracted using aerial photographs part of the test site were obtained
and data on the damage surveyed by a Local Development Office about 10 days after the damage and
used for the study.
Fig. 3 Procedures of the study
'ees by
511
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B7. Vienna 1996
