Oceanographic Forecast

What is the Derive Calculation?

O drift calculation consists of predicting the trajectory of floating objects (such as containers, drift boats, shipwrecks, etc.) or substances (such as oil stains) on the surface of the sea, considering the influence of various environmental factors:

• Ocean currents (surface and subsurface)
• Wind
• Wave
• Characteristics of the object or substance (form, buoyancy, drag coefficient, etc.)

Usefulness and Impact

The drift calculation is special relevance in the following areas:

• Search and Rescue (SAR): support for MRCC Lisboa, MRCC Delgada and MRSC Funchal to predict the trajectory of shipwrecks, drift boats or floating objects.
• Response to marine pollution incidents: prediction of the drift from hydrocarbons or other contaminants.

Drift predictions are essential to reduce search areas, optimize resources and increase the effectiveness of pollution rescue and mitigation operations. They are also used in emergency training, planning and response scenarios.

Methodology

CGEOMETOC uses high resolution oceanographic and atmospheric numerical models, as well as specific drift prediction models (OpenDrive or proprietary tools), adjusted to the regional conditions of the area of interest.

The procedure shall include:

1. Collection and analysis of environmental data (wind model, currents, waves).
2. Parametrization of the object/substance to simulate.
3. Execution of drift model.
4. Interpretation of results and production of drift charts or probable path animations.
5. Sending the results to the requesting entities (MRCC/MRSC).

Request Service

This service is provided exclusively to competent authorities in the framework of search and rescue and environmental protection operations, including:

• MRCC Lisbon, MRCC Delgada and MRSC Funchal
• Directorate-General of the Maritime Authority (DGAM)