The design of marine structures, such as offshore structures, wind parks, coastal structures, etc, generally starts with a metocean study to determine the mean, operational and extreme environmental conditions that the structures will need to withstand. Deltares frequently carries out metocean studies for a broad spectrum of clients such as project developers, governments, local businesses, contractors, oil and gas producers, etc. Our specialists have been working on a method to standardize the execution of metocean studies, by developing guidelines along with a MATLAB tool, called ORCA, which integrates the main aspects of analyzing metocean data.

ORCA (met Ocean data t Ransformation, Classification and Analysis) is a MATLAB Tool for analysis, classification and transformation of metocean data, developed by Deltares. Deltares frequently carries out metocean studies. These studies involve quite a lot of statistical analyses, which for a large part are carried out using ORCA. At the moment, there are five functionalities available on the ORCA tool.  Each one deals with a certain aspect of data analysis, namely:

  • Data validation – Procedures necessary for the determination of a “good dataset”. These include procedures for reading of different data, analysis of gaps in time series, data visualization, data comparison, error statistics and plots, and data correction.
  • Normal conditions – Procedures necessary for the determination of mean climates. Consisting of, among others, procedures for data classification, creation of wave roses, data transformation and definition of mean climate scenarios.
  • Extreme conditions – Procedures for extreme value analysis. Consisting of, among others, procedures for the collection of peak-over-threshold data, the collection of annual maxima data, definition of optimal threshold for the estimation of the generalized Pareto distribution parameters, return value estimation, fitting of statistical distributions.
  • Sea State analysis – Procedures for sea state analysis. Consisting of, among others, procedures for fitting of different spectral forms to discrete spectral data, estimation of sea state wave statistics (e.g.: number of waves, H1%).
  • Persistence statistics – Procedures for carrying out workability and accessibility analysis.

Graphical User Interface and toolbox

There is currently a GUI available with which the most important analyses available in the Data Validation, Normal Conditions and Extreme Conditions functionalities can be carried out. The remaining functionalities are available as MATLAB code and there are exemplary scripts and guidelines available on how to use them. When a client is only interested in the GUI then he requires no MATLAB since the GUI is available in a platform independent format.