Frankfurt (Oder), Germany 2001
Details:	JPG, 1500 x 1465 Pixel, 72 dpi	(842 KB)
Copyright:	European Space Agency (ESA)

This ERS SAR multitemporal image covers a large section of the River Oder around the town of Frankfurt, from Krosno (bottom right) to its confluence with the Warta. The magenta areas along the river are those flooded on the 5th August, while those in green-cyan where flooded only on the 6th August; the blue tones show areas flooded on both dates. The differences in the colours between this image and that of the 21st July are mainly due to the different techniques used: in this image scenes acquired on the 5th and the 6th of Augustwere compared with a reference scene acquired in May, and so the final picture containselements of all three scenes, giving a balanced multitemporal image that shows only the significant changes between the three scenes. The image of the 21st July compared just onescene that showed the flooding with a reference scene. In order to compose an RGB image from just two scenes the first principal component of the two scenes was also used; this technique enhances the variance between the two scenes, creating more colour variance in the final multitemporal image.