Recent work carried out has demonstrated the value of creating animations to visualise and depict change. A good example of this stems from the various studies carried out on the Black Ven landslide in Dorset (a World Natural Heritage Site), where a sequence of dated orthophotographs and digital elevation models have been generated over a number of years. These have been generated using initially analytical (1988-1989) and later digital photogrammetric methods (1995, 2001) using archival and contemporary imagery. It is now possible to bring these dated datasets together and to animate them and make the animations available via the internet. Instigated and other planned animations include:
1976, 1995, 2001, 2005
Digital elevation models:1946, 1958, 1976, 1988, 1995, 1998, 2000, 2001
Orthographic grids: 1958, 1969, 1976, 1988, 1995, 2001
Cross-section profiles: 1946, 1958, 1969, 1976, 1988, 2001
Morphological CHANGE: 1976 -1958, 1995 - 1976; 1998 - 1995; 2001 - 1998
Dated Flypasts: 1976, 2001, 2005 (be patient, 20Mb to download!)
Superimpose orthophotos onto Google Earth: 1976
Superimpose oblique aerial photographs onto Google Earth. 1948, 1958, 1976, 1988
(Download zip file, uncompress and double-click!)
The area of coast depicted is large (950 x 650 metres in size) and spatial changes great (40-50m of cliff-top recession);
All of these animations are spatially referenced to each other, so that differences represent genuine morphological change. Good points of reference in the orthophotographs are the two golf bunkers that "use to be" adjacent to the cliff edge (They were partially lost in February 2001, as shown by the July 2001 epoch!), also the major cliff line, left of centre which has been comparatively stable.
Other animations will be created from the following datasets, as and when time allows.
Note that movie files of image files are large so that downloads for the orthophotographs are slow ~3mins on a 56K modem! These images are of low-resolution to allow reasonable internet access times, much higher-resolution (0.2m) versions of the site are available.
This website has proved very popular and has resulted in a more comprehensive version commissioned for public display by the Charmouth Heritage Coast Centre, in Dorset. This includes higher resolution versions of the animations, including some new types! The interactive display can be viewed at CHCC or is available here.
A summary of the datasets:
|Date||Description||Digital Elevation Model?||Orthophotograph?|
|1946||"split vertical" RAF photos (1: 10,000)||Low resolution- manual measured||Possible|
|1958||Oblique- Cambridge University Collection (1:6,500)||5m resolution- manual measured||Possible|
|1969||Vertical- Cambridge University Collection(1: 4,000)||5m resolution- manual measured||Possible|
|1976||Vertical Aerial photos- Ordnance Survey (1: 7,500)||1m resolution||1m resolution|
|1988||Oblique hand-held photography||5m resolution- manual measured||Possible|
|1995||Vertical Aerial photos- NERC||1m resolution||1m/0.2m resolution|
|1998||Airborne laser scanning- Environment Agency||2m resolution||Unavailable|
|2000- Mar.||Vertical Aerial photos- Ordnance Survey (1: 7,500)||1m resolution||1m/0.2m resolution|
|2001- May||Airborne laser scanning- Environment Agency||2m resolution||Unavailable|
|2001- July||Vertical Aerial photos- NERC (1: 7,500)||1m resolution||1m/0.2m resolution|
|2005- July||Vertical Aerial photos- Copyright Getmapping Plc (1: 19,000)||2m resolution||0.15m resolution|
Brunsden, D. and Chandler, J.H., 1996. Development of
an Episodic Landform Change Model Based Upon the Black Ven Mudslide 1946-1995,
in Advances in Hillslope Processes, Anderson, M.G. and Brooks, S.M. (Eds),
J. Wiley, Chichester, UK, pp 869-896, ISBN 0 471 96774 2.
Chandler, J.H. and Cooper, M.A.R., 1988. Monitoring the
development of landslides using archival photography and analytical
photogrammetry, Land and Minerals Surveying, 6, pp. 576-584
Chandler, J.H. and Cooper, M.A.R., 1989. The extraction of positional data from historical photographs and their application in geomorphology, Photogrammetric Record, 13(73), pp. 69-78.
Chandler, J.H. and Moore, R., 1989. Analytical photogrammetry: a method for monitoring slope instability, Quarterly Journal Engineering Geology, 22, pp. 97-110.
Chandler, J.H., Cooper, M.A.R. and Robson, S., 1990.
Analytical aspects of small format surveys using oblique aerial surveys, Journal
of Photographic science, 37, pp. 235-240.
Chandler, J.H., 2001. Terrain measurement using automated digital photogrammetry, in Land surface evaluation for Engineering Practice, Engineering Egeology Special Publications 18, Griffiths, J.S. (Ed), Geological Society of London, London, pp. 13-18, ISBN 0267-9914/01.
Chandler, J.H. and Brunsden, D., 1995. Steady State
Behaviour of the Black Ven Mudslide: The Application of Archical Analytical
Photogrammetry to Studies of Landform Change, Earth Surface Processes and
Landforms, 20, pp 255-275, ISBN 0197-9337.
Walstra, J., Chandler, J.H., Dixon, N. and Dijkstra, T.A., 2004. Time for change - quantifying landslide evolution using historical aerial photographs and modern photogrammetric methods, The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. 34(Part XXX), Commission 4, Istanbul, 2004, pp. 475-48.
Walstra, J., Chandler, J.H., Dixon, N. and Dijkstra, T.A., ''Aerial photography + digital photogrammetry for landslide monitoring'', in Mapping hazardous terrain using remote sensing, Geological Society special publication No 283, R.M. Teeuw, Geological Society, London, 1st July 2007, pp 53 - 63, ISBN 978-1-86239-229-8.
Chandler, J.H., Lane, S and Walstra, J, ''Quantifying landform change'', in Applications of 3D measurement from images, J.Fryer, H.Mitchell, J.Chandler, Whittles Publishing, Caithness, 1st September 2007, 139-170, ISBN 978-1870325-69-1.
Other research work