WESM Data Dictionary: Reason Codes: 1m and Seamless

By NGP Standards and Specifications

In addition to general attributes, the Work Unit Extent Spatial Metadata (WESM) includes information on how data in a given work unit relates to 3D Elevation Program (3DEP) elevation product specifications. This information is shown in the product status codes. Product status codes include codes for categories and reasons. Reasons for the one-meter and seamless DEMs are discussed here.

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WESM Product Status Codes: Source DEM

For more information about the product status codes, please see the WESM introduction page.

Introduction

A work unit’s reason code gives the primary reason why it was assigned to a particular category. The reason codes are typically unique per category and product combination, though some codes are used for several products for some of the categories.

Links to other reason code attributes by product (links to other pages)

Quick links to sections by product and category (on this page)

One-meter reason codes
- Meets with variance
- Does not meet
Seamless reason codes
- Meets with variance
- Does not meet

Reason Codes for the one-meter DEM

onemeter_reason

Description: One-meter DEM reason code
Definition: Used to store the reason code for the one-meter DEM
Format: text
Length: 100 characters
Valid values:

Category	Reason code
Pending publication	Awaiting final absolute vertical accuracy assessment
Under review	Pending LPC/source DEM review
Meets	Meets 3DEP 1-m requirements
Meets with variance	See reason code list below
Does not meet	See reason code list below

One-meter reason codes for the *Meets with variance* category.
Reason code	Definition
LPC meets v.1.0 or earlier draft specification	LPC meets requirements of an earlier version of the LBS (draft version 13 or later but prior to version current with date of lidar production)
Non-lidar source - alternate	Non-lidar source data meets specifications for spatial accuracies and resolutions
LPC NPS <2ppsm and >1ppsm	NPS of LPC between 2 ppsm (QL2 requirements) and 1 ppsm (1-m requirements)
Horizontal accuracy - non lidar	Non-lidar source data suitable for producing DEM of 1-m or finer resolution
Source DEM meets with variance	See source DEM reason code

One meter reason codes for the *Does not meet* category.
Reason code	Definition
LPC does not meet	LPC does not meet source data requirements
Non-lidar source	Non-lidar source data does not meet specifications for spatial accuracies or resolution
LPC NPS <1ppsm	NPS of LPC less than 1 ppsm
Horizontal accuracy - non lidar	Non-lidar source data not suitable for producing DEM of 1-m or finer resolution
Vertical Accuracy - lidar	Source data does not meet 3DEP QL2 10.0 cm RMSEz threshold
Hydroflattening	Source DEM not hydro-flattened or missing breaklines necessary for hydro-flattening
sDEM unsuitable, other reason	Source DEM not suitable for creating 1-m DEM product, reason unspecified, see metadata
Source DEM does not meet	See Source DEM reason code
Source DEM not available	No source DEM available

Reason Codes for the Seamless DEM layers

seamless_reason

Description: Seamless DEM layers reason code
Definition: Used to store the reason code for the seamless DEM layers
Format: text
Length: 100 characters
Valid values:

Category	Reason code
Pending publication	Awaiting final absolute vertical accuracy assessment
Under review	Pending LPC/source DEM review
Meets	Meets 3DEP seamless requirements
Meets with variance	See reason code list below
Does not meet	See reason code list below

Seamless reason codes for the *Meets with variance* category.
Reason code	Definition
LPC meets v.1.0 or earlier draft specification	LPC meets requirements of an earlier version of the LBS (draft version 13 or later but prior to version current with date of lidar production).

Seamless reason codes for the *Does not meet* category.
Reason code	Definition
LPC does not meet	LPC does not meet source data requirements.
Source DEM resolution too coarse	Source DEM resolution coarser than seamless DEM being produced.
Source DEM not available	No source DEM (source DEM or 1-m DEM) available to update the Seamless layers.