Denise Sudom

Iceberg sightings, shapes and management techniques for offshore Newfoundland and Labrador: Historical data and future applications

For safe and efficient operations in the iceberg-infested waters offshore eastern Canada, accurate information on icebergs is needed. Databases on iceberg sightings, shapes and management techniques have been developed in order to bring all relevant iceberg information into one repository. Iceberg sightings have been recorded offshore Newfoundland and Labrador since the 1600s. Sighting methods, locations, yearly variability and uncertainties are discussed. In more recent times, detailed 2D and 3D measurements have been made of iceberg geometries, which are useful for structural load calculations. Techniques to deflect iceberg drift from critical offshore locations have also evolved over the past 40 years. The various methods that have been used for iceberg management are discussed, as well as the factors that affect their success rates. Relationships between historical iceberg populations and sea ice can be used to forecast iceberg severity in future seasons; updated correlations have been made between sea ice coverage and iceberg severity.

Protecting Offshore Pipelines Against Drifting Ice: A Discussion on Standards and Guidelines

In freezing waters, seabed gouging ice features (icebergs, pressure ridges) are a threat to offshore pipelines, which must be buried to a safe depth. Several standards and guidelines addressing this issue are examined and compared. The type of information that each code deems significant varies considerably — factors that are important to some code writers are not to others. API RP 2N, CSA-ISO 19906, CSA Z662 and DNV OS F101 direct the users to specific factors that either must or could be considered for design, but do not indicate what is to be done with them. In contrast, the RMRS rules are highly prescriptive. From a code user’s perspective, a comprehensive listing of all factors involved in ice-seabed-pipe interaction might provide better guidance in assessing what needs to be considered. This assessment could also be divided into three distinct operations: determination of design gouge depth, determination of clearance below the design gouge depth, and determination of pipeline response.Copyright