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Exercise 3: Lava detection: crisis images and maps - continued  At this stage, most of the lava has already spread, but not all. The eruption lasted until around 9 August. The 2001 lava in the western part is not seen in the FCCs, although it is already marked on the map.
The lava is still visible in band 6 (hot = white) but no longer distinguishable from others in mid-IR. In the 4-5-3 combination, many dark coloured lava streams can be seen, but only in band 6 can the new one be identified and distinguished from the others. Snow is clearly detectable (cold = dark). In band 6 you cannot see any more hot lava in the western area, as it was not there yet at that point in time. See the lava map for comparison.
We will now work with a post-crisis image after the end of the eruptions from November 2002 to January 2003. This image contains all the changes from 2001 and 2002/03 compared to the image of 1999.
File > Open > RGB 4-5-3 Look at the Image Information and check if the projection is the same in both images.
15. Why does the 2003 data consist of only 7 bands and is missing band 8? 16. Can you detect volcanic activity in the 2003 image?
17. Can you identify any new lava flows?
19. Compare with the lava map from 2002/03: Can you identify any new lava? Display some colour composites or bands of 1999 and 2003 next to each other and compare them (e.g. 4-5-3).
Last update: 17 April 2013
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