Brewar, P., Evans, B., Hodges, C., Macklin, M. and Williams, R. 2014. WP6 Demonstrators Estimating inundation extent from a distance. Presentation as part of the COBWEB Workshop, 22nd May 2014, y Plas, Dyfi, UK.

1. WP6 Demonstrators
Estimating inundation extent from a distance
May 2014
Paul Brewer
Barry Evans
Crona Hodges
Mark Macklin
Richard Williams

2. Overview
• User interface design
– Navigating interface
– Drawing on photos
• Calculating inundation extents
– Location at a distance
– Uncertainties
– Fuzzy inundation
• Next steps

3. User interface design
• Simple to use
in field
• Encourages
capture of
useful data
• Data capture
divided up
into actions

4. User interface design
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5. User interface design
• Additional interaction
• Guided steps

6. Calculating Flood extent
x
• User position
• Estimated height
• Orientation
• Angle of device
• Terrain

7. Uncertainties
Device:
• GPS Accuracy
• Height of device
• Orientation (Compass bearing)
• Angle of tilt
• Generalisation of Terrain
User:
• Placement of marker
• Accuracy of “swipe line”
Capture information
from device &
metadata
Reduce uncertainty
via multiple photos

8. Uncertainties
Graph of distance vs. error (Meek et al., 2013)

9. Uncertainties
x
One unique location for X becomes an area that
depicts the likely locations for X based on
uncertainties during capture.

10. Inundation calculation
• Derive inundation extent
from user values
• Multiple possibilities due to
uncertainties
• Derived likelihood of
inundation based on user
data

11. Next steps
• Field test
– Data collection
– App usability
– GPS Accuracy
• Development
– Derive geo-fences for Quality Control
– Automate inundation extent calculation
– Flood modelling
– Boulder Berms with Lichenometry assessment for
deriving historical flood record