Clouds and Contrails

One of the projects we are working on is the SCSI/ESA funded "Satellites for BIM" assessing the suitability of satellites as a tool for planning and monitoring construction projects in coastal regions and ensuring environmental compliance throughout the project and afterwards when the site is operational. We have been awarded some TerraSARX Staring Spotlight imagery and some Pleiades Tri-Stereo Optical. The TSX data was very easy to order, due to the cloud penetrating capabilities, it was done in 2 emails. The optical on the other hand must wait for a cloud free opportunity to coincide with the satellite overpass - and we have had to cancel the last three acquisitions due to this. The weather over this weekend was great, really as good as Ireland gets in the summer but unfortunately the next overpass was not due until today. Looking at the HighRes visible image over the country there is a bank of cloud further north but Dublin bay (our target site) is relatively free from cloud cover, which is very promising. However, you do notice a network of intersecting lines of clouds that look to me from the pattern to mimic air traffic passing over Ireland to the UK and the rest of Europe and are therefore almost certain to be contrails left by airliner traffic overhead - and these are sitting over the bay.... I have listened to Gillian Whelan in UCC present a number of times on these - contrails can form a foundation for other clouds to form on, so they get bigger with time rather than smaller and they can spread over a significant distance. They also contribute to global warming as they reflect some of the suns energy back down to the earths surface.

Hopefully they wont interfere with the satellite tasking, it should be due in the next hour. Bad weather is due back again on Wednesday.


Update - Rejected!

Update 2 - What a difference a few days made. This was the S2a overpass on the 17th, hardly a cloud to be seen from Waterford to Armagh.

Update 3 - Success. We got lucky on the Tuesday. Tri-stereo Pleiades imagery captured - looking forward to seeing what we can make with it.