Glossary#
- Cartopy#
A python package for producing maps, and other geospatial data. Allows plotting on these maps, over a range of projections.
- CF Conventions#
Rules for storing meteorological Climate and Forecast data in NetCDF Format files, defining a standard metadata format to describe what the data is. This also forms the data model which iris is based on.
- Coordinate#
A container for data points, comes in three main flavours.
- Dimensional Coordinate -
A coordinate that describes a single data dimension of a cube. They can only contain numerical values, in a sorted order (ascending or descending).
- Auxiliary Coordinate -
A coordinate that can map to multiple data dimensions. Can contain any type of data.
- Scalar Coordinate -
A coordinate that is not mapped to any data dimension, instead representing the cube as a whole.
- Cube#
Cubes are the main method of storing data in Iris. A cube can consist of:
Array of Phenomenon Data (Required)
- Cell Method#
A cell method represents that a cube’s data has been derived from a past statistical operation, such as a MEAN or SUM operation.
- Coordinate Factory#
A coordinate factory derives coordinates (sometimes referred to as derived coordinates) from the values of existing coordinates. E.g. A hybrid height factory might use “height above sea level” and “height at ground level” coordinate data to calculate a “height above ground level” coordinate.
- Dask#
A data analytics python library. Iris predominantly uses Dask Arrays; a collection of NumPy-esque arrays. The data is operated in batches, so that not all data is in RAM at once.
- Fields File (FF) Format#
A meteorological file format, the output of the Unified Model.
- GRIB Format#
A WMO-standard meteorological file format.
More information: GRIB 1 User Guide | GRIB 2 User Guide.pdf- Lazy Data#
Data stored in hard drive, and then temporarily loaded into RAM in batches when needed. Allows of less memory usage and faster performance, thanks to parallel processing.
- Long Name#
A name describing a phenomenon, not limited to the the same restraints as standard name.
- Matplotlib#
A python package for plotting and projecting data in a wide variety of formats.
- Metadata#
The information which describes a phenomenon. Within Iris specifically, all information which distinguishes one phenomenon from another, e.g. units or Cell Methods
- NetCDF Format#
A flexible file format for storing multi-dimensional array-like data. When Iris loads this format, it also especially recognises and interprets data encoded according to the CF Conventions.
More information: NetCDF-4 Python Git- NumPy#
A mathematical Python library, predominantly based around multi-dimensional arrays.
- Phenomenon#
The primary data which is measured, usually within a cube, e.g. air temperature.
- Post Processing (PP) Format#
A meteorological file format, created from a post processed Fields File (FF) Format.
- Real Data#
Data that has been loaded into RAM, as opposed to sitting on the hard drive.
- Standard Name#
A name describing a phenomenon, one from a fixed list defined at CF Standard Names.
- Unit#
The unit with which the phenomenon is measured e.g. m / sec.
- Xarray#
A python library for sophisticated labelled multi-dimensional operations. Has a broader scope than Iris - it is not focused on meteorological data.