A method of monitoring urban expansion and environment changebased on TM data is described.Four WRS 123/32 scenes of TM images of Beijingcity acquired on Oct.3

1984

Sep.26

1987

Oct.17

1989 and Oct.25

992 res-pectively were registered each other with high geometric accuracy less than 0.5 pixelerrors and normalized at the same radiative level of 1984’s TM image. Throughnumerical analysis of TM data

a set of effective processing

interfering factors wereeliminated in extracting urban expansion and environment change information from1984 to 1992.Finally

a set of variation maps of bult-up area

greenlands

waterbody and heat island were obtained by means of micro computer image processingsystem. The bult-up area extended about 3% each year.The water body increasedfrom 4.9 to 19.1 squarekms.The greenlands where the trees

shrubs

grass and flo-wers were growing

have been changed from 132.1 to 151.7 squarekms.All of thesedemonstrate that the quality of Beijing environment has been improved graduallyduring the last eight years.