Hello Bathy Lidar Working Group Members,
I did a review of the newly drafted bathymetric lidar specifications recently posted guideline and wanted share my observations, thoughts, and maybe potential suggestions.
First and foremost, the guideline is both well-constructed and comprehensive, addressing the essential components of bathymetric lidar collection, processing, and deliverables. Therefore, I took the opportunity to do the review in two distinct perspectives: one as a technical bathy lidar enthusiast and the other as a non-technical end user, relying on this document for planning, managing, and validating bathy lidar surveys. My hope is that my comments will be helpful for the document creation, but more so to spur insightful discussions within our group to further our collective expertise.
Collection Guidelines
- Guidance on Buffer Adjustment: It may be beneficial to add language outline the circumstances under which adjusting the 100-meter buffer is permissible. If applicable, outline any constraints or special considerations related to the collection area.
- Include Detailed Parameters: Outline collection parameters that should be considered.
- Quality Level-lidar bathymetry specifications: Although quality levels are mentioned, there may be a room to increase the level of detail or explanation or provide guidance on how to select or apply these levels in different scenarios.
- Areas for Further Exploration:
- Sensor Specifications: A detailed table summarizing generic sensor specifications for various environments like shallow coastal waters, deep oceans, and riverine systems, without brand identification, could be valuable.
- Considerations might include the wavelength, pulse rate, beam divergence, and receiver sensitivity.
- Calibration and Validation Procedures: Inclusion of guidelines, for pre-deployment calibration to regular monitoring, which could include:
- Pre-deployment calibration, including laboratory procedures and sensor alignment checks.
- In-situ validation using known reference targets or ground-truth measurements.
- Post-processing calibration to adjust for systematic errors.
- Regular monitoring and re-calibration to maintain data quality.
- Weather and Seasonal Considerations: Provide guidance on thresholds or measurement methods for water conditions, including:
- Water clarity and turbidity levels suitable for bathymetric lidar.
- Influence of wave height, tide levels, and currents on data collection.
- Methods or tools to measure and monitor these conditions in real-time.
- Strategies to adapt to changing water conditions during a survey.
- Water Conditions: Guidance on acceptable water conditions and real-time monitoring techniques for effective data collection.
- Total Propagated Uncertainty (TPU): Incorporation of TPU assessment adds rigor to data quality reporting and helps in minimizing uncertainty. Provide guidance on how this should be recorded and conveyed in the data and/or reporting and metadata.
- Contingency Planning: Guidance on risk assessment, backup plans, and response protocols ensures resilience in the face of unforeseen challenges.
Data Processing & Handling
- Organization: Consider dividing the content into clear subsections or headings for better readability.
- Include Security and Integrity Protocols: Define protocols for data security, integrity, and storage, ensuring safe handling of the data.
- Areas for Further Exploration:
- Data Quality Assurance: Maybe a dedicated subsection or appendix, outlining the quality control workflow.
- Interoperability: Guidance on compatibility with other systems facilitates seamless integration with various geospatial and hydrographic data types.
- User Accessibility: An accessible glossary, cross-referencing, and visual aids make the document more approachable, especially for non-experts.
- Outline Processing Workflow: Include a outline of the data processing workflow, connecting different steps and requirements.
Deliverables
- Opportunity for Elaboration: The section could expand on what constitutes ancillary products and provide a detailed list or categorization of the required deliverables.
- Areas for Further Exploration:
- Timeline and Schedule: Guidance on key milestones, dependencies, and contingency plans provides clarity on expected timelines for delivery.
- Integration with Other Data Types: Comprehensive guidance on integrating deliverables with other geospatial or hydrographic data provides a more holistic perspective.
- Specify Formats and Standards: Define the required formats, standards, or conventions for each deliverable, ensuring consistency and compatibility.
I hope these insights will prove useful and look forward to engaging with all of you on these topics and collectively advancing our knowledge and practice.
Best Regards,
Danial
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Danial Mariampillai
NRCan (CCMEO)
Victoria BC
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Original Message:
Sent: 08-07-2023 06:27 PM
From: Nicholas Johnson
Subject: Bathy Lidar Specification
Tomorrow I'll be replacing the Bathy Lidar Base Spec with the most recent changes and preparing for next Monday's BWG meeting and looking forward to any comments or feedback from the community. Let's us this thread to continue discussion around the specification.
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Nicholas Johnson
Physical Scientist
USACE
Kiln MS
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