SIMA Reference System

1. Coordinate system

sima system

  • A right-handed coordinate system. The angles are measured from X axis in a counter-clockwise direction

2. Relative Compass Angle

relative angle

  • Relative compass angle \(\psi\) is given between analysis x-axis and north direction in counter-clockwise direction

  • If the relative compass angle is 0, the SIMA reference system is a North-West-Up system ,where the positive X axis is pointing to the North and positive Y axis to the west

3. Wave

  • Wave direction: Going to

    • Direction from which the waves are propagating towards, i.e 90 degrees → waves are going to Y+

4. Wind

  • Wind direction: Going to

    • Direction from which the wind is blowing, i.e 90 degrees → wind is going to Y+

  • Wind levels are measured from the mean water level positive upward

5. Current

  • Current direction: Going to

    • Direction wich the current is flowing to,

    • 90 degrees → current is going to Y+

  • Current levels are measured from the mean water level positive upward