Downloaded From: http://proceedings.spiedigitallibrary.org/ on 10/22/2015 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx 
The vertical accuracy of all three data sets in the very shallow water zone shows a relatively small amount of small 
difference between the laser grid and echo sounding points, which may be due to the poor echo sounding data. The first 
campaign does not satisfy the confidence level of TVU niax . but the percentage of differences came close to 95% between 
4-6 m depth. The second and third campaigns fulfill the requirement of TVU max up to 11 m and 8 m depth, respectively. 
5. CONCLUSION 
In this paper, we present some results of the project ‘Investigation on the use of airborne laser bathymetry in 
hydrographic surveying’, in which the applicability of the ALB for monitoring the German Baltic Sea Coast is being 
analyzed in cooperation with the German Federal Maritime and Hydrographic Agency. The goal is to investigate the 
ALB technique and to determine areas for which ALB is potentially more economical than ship-based echo sounding. 
For the first campaign a Riegl VQ-820-G sensor was used, which is designed up to one Secchi depth under certain 
conditions, but in the tests about 97.7% of the observed points classified as seabed have a depth of less than 0.7 x Secchi 
depth. High point densities are observed in very shallow water regions. For the second and third campaign a Chiroptera 
sensor with a nominal penetration depth of 1.5/ Secchi depth was used. The pulses reached up to 1.3 x Secchi depth. On 
the one hand, the maximum point density is lower than the results obtained by the Riegl sensor, probably due to the 
lower pulse rate and the smaller strip overlap. On the other hand, the point density of the Chiroptera sensor decreases 
only slowly with depth. We also show that the shallow areas are well covered up to 0.7* Secchi depth by a Riegl sensor 
and up to 1.0x Secchi depth by a Chiroptera sensor. The vertical accuracy of ALB was investigated in a comparison to 
echo sounding and was compared to the IHO Standards for Hydrographic Surveys (S-44). In order to fulfill the 
requirements, 95% of the differences must be less or equal ±0.5 m. The results of the first campaign do not meet the 
demanded vertical accuracy standards, but for approx. 94% of the seabed points of a depth of 3-6 m the differences were 
within ±TVU max . The second and third campaign satisfied the requirement in 4-11 and 3-8 m depth, respectively. Overall, 
over 92.5% of the seabed points of the three campaigns showed depth differences of less than 0.5 m compared to the 
echo sounding data. 
In future work the full waveform information will be used for a classification of the points into several seabed substrates 
and underwater vegetation. 
REFERENCES 
[1] Irish, J. L. and Lillycrop, W. J., "Scanning laser mapping of the coastal zone: the SHOALS system," ISPRS Journal 
of Photogrammetry and Remote Sensing 54(2), 123-129 (1999). 
[2] Irish, J. L., McClung, J. K. and Lillycrop, W. J., "Airborne Lidar Bathymetry-The Shoals System," Bulletin - 
International Navigation Association, 45-54 (2000). 
[3] Hickman, G. D. and Hogg, J. E., "Application of an airborne pulsed laser for near shore bathymetric measurements," 
Remote Sensing of Environment 1(1), 47-58 (1969). 
[4] Guenther, G. C., Cunningham, A. G., LaRocque, P. E. and Reid, D. J., "Meeting the accuracy challenge in airborne 
lidar bathymetry," Proc. EARSeL-SIG-Workshop LIDAR, Dresden/FRG, 1-27 (2000). 
[5] Mallet, C. and Bretar, F., "Full-waveform topographic lidar: State-of-the-art," ISPRS Journal of Photogrammetry 
and Remote Sensing 64(1), 1-16 (2009). 
[6] Wang, C. and Philpot W. D., "Using airborne bathymetric lidar to detect bottom type variation in shallow waters," 
Remote Sensing of Environment 106(1), 123-135 (2007). 
[7] Narayanan, R., Sohn, G., Kim, H. B., and Miller, J. R., "Soft classification of mixed seabed objects based on fuzzy 
clustering analysis using airborne LIDAR bathymetry data," Journal of Applied Remote Sensing 5(1), 053534- 
053534-24 (2011). 
[8] Tulldahl, H. M. and Wikstrom S. A., "Classification of aquatic macrovegetation and substrates with airborne lidar," 
Remote Sensing of Environment 121, 347-357 (2012). 
[9] Pe’eri, S., Morgan, L. V., Philpot, W. D. and Armstrong A. A., "Land-Water Interface Resolved from Airborne 
LIDAR Bathymetry (ALB) Waveforms," Journal of Coastal Reasearch 62, 75-85 (2011). 
[10] Doneus, M., Doneus, N., Briese, C., Pregesbauer, M., Mandlburger, G. and Verhoeven, G., "Airborne laser 
bathymetry - detecting and recording submerged archaeological sites from the air," Journal of Archaeological 
Science 40(4), 2136-2151 (2013). 
Proc. of SPIE Voi. 9638 96380Z-8