Glossary

data kind
data kinds

Descriptive term for what the data measures. Common data kinds are brightness temperature, reflectance, or radiance. Data kinds are created and set by the reader. This is similar to “standard_name” in CF compliance, but is less restrictive. Note that Data kinds are different from data types.

data type
data types

Size or format of the binary representation of the data. For example an 8-bit unsigned integer versus a 32-bit floating point number. Data types are different from data kinds. Data types consist of two parts: the format of the data and the number of bytes used.

dataset
datasets

Synonym for product. This term is used in the SatPy python library.

glue script

The script connecting every component together. A glue script connects a reader, the remapper, compositors, and a writer. The only glue script in Polar2Grid is called polar2grid.sh, but in previous versions there were glue scripts named <reader>2<writer>.sh. The bash script is simply a wrapper around the python call python -m polar2grid.glue <reader> <writer> -vv ….

gridded product
gridded products

Products that have been mapped to a uniform grid. These are typically associated with modern geostationary satellite imagery or they can be the result of resampling swath products to a projected uniform grid.

product
products

A swath or grid of instrument data. When read as an unprojected/ungridded array of data this may be referred to as a swath product. If read from a projected/gridded data file or after a swath product has been resampled it is considered gridded product.

raw product
raw products

Swath product created by a reader requiring little more than reading the data from a data file. It is common for raw products to require scaling from the raw data stored in the file using a scaling factor and offset. There are also a few cases where raw products require additional masking (ex. cloud clearing) that requires another product. In this way, raw products are sometimes treated as secondary products. To allow for more flexibility when raw products require extra processing, readers should consider having access to the original raw product and a secondary product created from that original product, rather than one single product. Obviously this depends on the usefulness of the original product to potential uses.

secondary product
secondary products

:term:Swath product <swath product>` created by a reader requiring one or more other products and some extra processing. Secondary products may require raw products or other secondary products.

swath product
swath products

Products representing the direct observations of a polar-orbitting satellite instrument. Swath products are not guaranteed to be uniformly spaced and are usually not.