Additional Attributes

Element Description

The Addition Attribute element is used to describe unique characteristics of the resource which extend beyond those defined in other metadata fields.

Best Practices

The Additional Attributes metadata concept can be used to describe unique characteristics of a dataset beyond what is covered in the existing metadata model. For example, cloud cover, tile number, or acquisition mode are characteristics that could be provided as additional attributes, since there are no pre-existing metadata fields for these types of information in the Unified Metadata Model (UMM). All Additional Attributes must be defined in the collection level metadata and should also be provided in the granule level metadata. If an additional attribute is provided in granule level metadata, but has not been defined in the parent collection, then validation issues may occur.

There are fourteen sub-elements that comprise Additional Attributes:

Name: The name/ label for the additional attribute. Providing a Name is required.

Description: A free-text description of the additional attribute. Providing a description is required.

Value: The actual value of the additional attribute. Provide the value in the collection level record if it is the same for all granules across the collection. If the value of the additional attribute differs by granule, then leave value blank at the collection level. (See examples below).

DataType: The data type of the additional attribute value. Providing a data type is required. This is a controlled vocabulary field in UMM-Common with the following options: STRING, FLOAT, INT, BOOLEAN, DATE, TIME, DATETIME, DATE_STRING, TIME_STRING, DATETIME_STRING

Measurement Resolution: The smallest unit increment to which the additional attribute value is measured. Providing a measurement resolution is optional.

Parameter Range Begin: The minimum value of the additional attribute over the whole collection. This only applies to attributes that are continuous in nature. Providing a parameter range begin is optional.

Parameter Range End: The maximum value of the additional attribute over the whole collection. This only applies to attributes that are continuous in nature. Providing a parameter range begin is optional.

Parameter Units Of Measure: The standard unit of measurement for the additional attribute. For example: meters, hertz. Providing a parameter unit of measure is optional.

Parameter Value Accuracy: An estimate of the accuracy of the values of the additional attribute. For example, for AVHRR: Measurement error or precision-measurement error or precision of a data product parameter. The accuracy must be specified as a percentage or the unit with which the parameter is measured. Providing a parameter value accuracy is optional.

Value Accuracy Explanation: Describes the method used for determining the parameter value accuracy that is given for this additional attribute. Providing a value accuracy explanation is optional.

Group: Identifies a namespace for the additional attribute name. Providing a group is optional. 

Update Date: The date this additional attribute information was updated. Providing an update date is optional. 

Typically, an additional attribute is either the same value for the entire collection or the value varies. This results in 2 possible scenarios:

1. The Additional Attribute value is the same for all data in the collection. In this case, the additional attribute "Value" field should be populated in the collection level metadata. Populating the "Value" field at the collection level indicates that the value is the same for all granules in the collection. For example, if cloud cover is the same (let's say 50%) for the entire dataset, the metadata would look like this:

   Example 1: Additional Attribute that is the same for all granules in a dataset. Note that the value remains the same at the granule level. 

   Collection Level Metadata	Granule Level Metadata file 1	Granule Level Metadata file 2
   "AdditionalAttributes": [    {      "Name": "Cloud Cover",      "Description": "Percent cloud cover",      “Value”: “50”,      "DataType": "INT", “ParameterUnitsOfMeasure”: “Percent”    },	"AdditionalAttributes": [    {      "Name": "Cloud Cover",      “Value”: “50”,    },	"AdditionalAttributes": [    {      "Name": "Cloud Cover",      “Value”: “50”,    },

2. The Additional Attribute value varies across the collection. In this case, the additional attribute "Value" field should be left blank in the collection level metadata. Excluding the "Value" field at the collection level indicates that the value changes from granule to granule, and that the granule level metadata should be referenced to determine the value of the attribute for that particular data file. For example, if cloud cover varies across the dataset, the metadata would look like this:
   

   Example 2: Additional Attribute that varies from granule to granule. Note that the value is not provided at the collection level and that the value is different for each of the granules. 

   Collection Level Metadata	Granule Level Metadata file 1	Granule Level Metadata file 2
   "AdditionalAttributes": [    {      "Name": "Cloud Cover",      "Description": "Percent cloud cover",      "DataType": "INT", “ParameterUnitsOfMeasure”: “Percent”    },	"AdditionalAttributes": [    {      "Name": "Cloud Cover",      “Value”: “30”,    },	"AdditionalAttributes": [    {      "Name": "Cloud Cover",      “Value”: “73”,    },

Examples: 

Group: "gov.nasa.gsfc.gcmd"

Value: "42a420d8-04bd-4b2f-ad2a-8adc138faa04"

Name: "metadata.uuid"

Description: "Not provided"

DataType: "STRING"

note: add table example where the attribute is the same for all granules, and one where it is different

Metadata Validation and QA/QC

All metadata entering the CMR goes through the below process to ensure metadata quality requirements are met. All records undergo CMR validation before entering the system. The process of QA/QC is slightly different for NASA and non-NASA data providers. Non-NASA providers include interagency and international data providers and are referred to as the International Directory Network (IDN).

Please see the expandable sections below for flowchart details.

Dialect Mappings

UMM Migration

Future Mappings

ADD EXAMPLE

-AdditionalAttributes: [
   - {
         Group: "gov.nasa.gsfc.disc",
         Value: "1 month",
         Name: "Data Granularity",
         Description: "The time coverage of individual data granules.",
         DataType: "STRING"
     },

History

UMM Versioning

ARC Documentation