This document describes the basic meteorological Conceptual Model objects (a.k.a Meteorological Objects) used at Finnish Meteorological Institute as GML 3.1.1 Features. The concrete objects and properties are described in separate schema files.
For detailed info see documentation
Author: Ilkka Rinne / FMI 2009.
Abstract parent type for Met Objects defined line segments between an ordered set of geospatial points.
The points defined in each of the given line segments should be considered as one consecutive array of geospatial points. If there are more that one segment, the first point (in the orientation order) of each of the segments following the first one is ignored (the first and the last point coordinates must always represent the same point).
The orientation of the line is defined by attribute "orientation", starting from the first position in the position list and ending to the last position if positive. This may or may not affect the semantics and the rendering of the line object (depending on whether the concrete types have a natural direction or not).
If elevation property is given, its value must be added to possible height value of each of the points in the each line segment. If the CRS of the points is 2-dimensional, the value of the elevation should be interpreted as the static height value of each of the given (control)points.
Surface object's area may be defined either as a single "anonymous", continuous surface patch or using named geographic regions (e.g. administrative areas).
When using the "anonymous" definition, the surface can be an abstraction of a portion of ground (like rain or cloud area) or an elevated surface at some level above ground.
The target area is defined by element "surface" containing one exterior ring (closed route through n coordinate points) and zero or more interior rings defining excluded areas ("holes") inside the exterior. type of the interpolation between the surface points can be specified by using attribute "interpolation".
If elevation property is given, its value must be added to possible height value of each of the points in the each line segment. If the CRS of the points is 2-dimensional, the value of the elevation should be interpreted as the static height value of each of the given (control)points.
An alternative for "anonymous" surface patch definitions is to use a set of know and named, usually administrative areas. These regions may be give inline or by references to the set included in the "sharedGeographicRegions" list of the containing Met Object group.