NDVI data continuity between Beijing-1, TM, and SPOT

Multi-sensor NDVI(Normal Different Vegetation Index) continuity is very important in long-term earth observation and climate research. Correlation coefficient is chosen to analyse the continuity of NDVI between medium resolution satellites: Beijing-1, TM(LandSat-5), SPOT-4. After the selection of sample pixels(remove pixels that contain water and great topographic area), results shows that Beijing-1 NDVI has very good linear correlativity with TM and SPOT(correlation coefficients higher than 0.97). And further statistical comparison between Beijing-1 NDVI and TM,SPOT NDVI data shows that Beijing-1 NDVI are more similar to TM´s than SPOT´s. The present results suggest that Beijing-1 NDVI has very good continuity with TM and SPOT NDVI in flat area. This shows that Beijing-1 has very good detectation ability and will extend Beijing-1´s application field.