German Project Laserbathymetry27 May 2014

19.04.23 Ellmer: German Project 2

Content

• Aim of the project

• Questions to be answered

• Organization of the project

• Preliminary conclusions

Aim of the project

• Not to lose track of important actual developments

• How much money do I need for surveying the relevant areas

• Many questions in detail:

• Which areas are relevant for laserbathymetry?

• Where is laserbathymetry cheaper than shipborne measurements?

19.04.23 Ellmer: German Project 3

Questions to be answered

Hydrographic Surveying in shallow areas

•Role of environment (visibility, sea grass,…)

•How deep is it possible?

•Surveying in shallow lagoons (backwater)

•…

19.04.23 Ellmer: German Project 4

Questions to be answered

Wreck Search

•Objects of 2m size (IHO S-44)? Which size is certainly detectable

•Is detectable size depth dependent?

19.04.23 Ellmer: German Project 5

Questions to be answered

Coastline

•Possible to determine a DTM (1m until -1m)? And to detect 0-m-line?

•What about data gaps in very shallow water?

19.04.23 Ellmer: German Project 6

Questions to be answered

Call for tenders

•Possible flight parameters for all purposes (DTM, wreck search, coastline)?

•What has to be considered when writing a call

•How to calculate a price for budget planning?

19.04.23 Ellmer: German Project 7

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Organization of the project

Overview

•3 years project 2012 - 2014

•Scientific Cooperation

• Leibnitz Universität Hannover

• 1 scientist

•3 flights autumn 2012, 2013, spring 2014

•Frequent meetings with different interested organizations

• HO and university

• Water and shipping administration (federal)

• Coastal protection (states)

• Navy (federal)

• Land survey (states)19.04.23 Ellmer: German Project 8

19.04.23 9Ellmer: German Project

Organization of the project

2012

•Request for high resolution

•Milan with Riegl VQ820G

•3 heights (500m, 700m, 300m)

10Ellmer: German Project19.04.23

Organization of the project

2013

•Request for high resolution plus deeper penetration

•AHAB/TopScan with Chiroptera / HawkEye II

•September 2013

•Addition of artificial reefs

1119.04.23 Ellmer: German Project

Organization of the project

2013

•Request for high resolution plus deeper penetration

•AHAB/TopScan with Chiroptera / HawkEye II

•September 2013

•Addition of artificial reefs

12Ellmer: German Project19.04.23

Organization of the project

2014

•Request for high resolution plus deeper penetration

•AHAB/Aerodata with Hawkeye III

•Flight in April 2014 with Chiroptera

•Additional flight with Hawkeye III in autumn

13Ellmer: German Project19.04.23

Organization of the project

2013 + 2014

•Addition of artificial reefs

Organization of the project

Artificial reefs

•Good for checking the accuracy

•Located close to Rostock

•Accurately surveyed by multibeam

19.04.23 Ellmer: German Project 14

reefs

Riff Nienhagen

Preliminary conclusions

3 flights

•Much information

•Easier to collect data than to process all information

•Evaluation 2013 is not finished

•Processing 2014 just started

•Conclusions at this time very rough

19.04.23 Ellmer: German Project 15

Preliminary conclusions

Very preliminary

•Accuracy not the main problem

•Dependent on careful processing

• How to check the carefulness?

19.04.23 Ellmer: German Project 16

Preliminary conclusions

Data gaps

•Data very inhomogeneous

• From >5 points/m² to >5 m²/point

•Gaps even in shallow areas

• Still to develop: Which density is too low for S-44?

19.04.23 Ellmer: German Project 17

Preliminary conclusions

Wrecks, Obstructions

•At this time not reliable to detect

•Riff Rosenort data from Chiroptera 2013

19.04.23 Ellmer: German Project 18

Preliminary conclusions

19.04.23 Ellmer: German Project 19

Résumé:

•LIDAR is a very interesting development for shallow waters;

•Traditional methods have disadvantages in shallow areas:

• Single-beam data provide too large gaps in-between;

• Multi-beam surveys need too many survey lines;

•LIDAR does not provide an alternative but a complement;

•Combination of land and sea data becomes more important

•A wider scope of the use and users of the data is necessary:

• Not only safety at Sea (nautical charting)

• Not only coastal protection

This is in line with the Theme for World Hydrography Day 2014:

Hydrography – much more than nautical charting

19.04.23 Ellmer: German Project 20