C-CAP Niihau 2005 Land Cover

Create custom data files by choosing area, map projection, file format, etc.

Date that the source FGDC record was last modified.

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details.

Partial upload of Positional Accuracy fields only.

Partial upload to move data access links to Distribution Info.

NOAA OCM | Source Geospatial Form: remote-sensing image | Type of Source Media: DVD/CD-ROM

This dataset was created by Sanborn (www.sanborn.com). This version of

the classification is the High Resolution Land Cover (2005-era) for the

Island of Niihau, HI.

Summary:

This section outlines the classification procedure for the Niihau High

Resolution C-CAP. Quickbird imagery used in producing this land cover

product was also utilized in producing an associated impervious surfaces

layer for the island. The mapping approach utilized an object oriented

approach. A calibration visit was not conducted. Non impervious features

were mapped using a 0.5 acre minimum mapping unit (MMU).

Pre-processing steps: The Quickbird mosaic utilized for this project was

provided from Digital Globe as an orthorectifed, georeferenced product

and was consistent with the quoted 1:12000 spatial accuracy. In

conjunction with the Quickbird mosaic, Sanborn used an IKONOS mosaic, as

well as a DTM created from a 5m radar collect for the island. The

original return image from the radar was also utilized.

Field-Collected Data: Training data was not collected.

Classification: Segmentation - Image segmentation was completed at

multiple scales using the multispectral (2.4 m) imagery in order to

group like spectral and textural objects within the imagery. For

consistency, the associated impervious data set was incorporated into

the segmentation layer as a boundary delimiter. Segments can share

boundaries of an impervious surface, but can never overlap an impervious

surface.

Automated Classification, image segments are classified using a decision

tree classifier in See5 software and an iterative nearest neighbor

classifier in Definiens software. Nearest neighbor training data is

collected through analyst interpretation or ancillary data sets and used

to calibrate the classification algorithm.

Automated Classification Refinement - Models are built to refine or

reclassify land cover areas by utilizing the wealth of attribute

information linked to each segment within Definiens.

Classification Edits - As with any automated or semi-automated land

cover classification there are often inconsistencies in the land cover

map. The final step before map finalization was to remove inaccuracies

through manual segment labeling as interpreted by an analyst.

Map Finalization - Sanborn used independent reviewer's comments to

further refine the land cover map.

Post processing:

The change detection process used to create the 2010 Niihau C-CAP product highlighted some errors in the 2005 land cover map. To create a more accurate product these issues we addressed by NOAA through a combination of spatial models and manual edits. While the changes may not be large in area and/or be directly reflected in the accuracy assessment, we feel the products more accurately reflect the land cover for the time period.

Attributes for this product are as follows: 0 Background 1 Unclassified

2 Impervious 3 4 5 Developed, Open Space 6 Cultivated Crops 7

Pasture/Hay 8 Grassland/Herbaceous 9 Deciduous Forest 10 Evergreen

Forest 11 Mixed Forest 12 Scrub/Shrub 13 Palustrine Forested Wetland 14

Palustrine Scrub/Shrub Wetland 15 Palustrine Emergent Wetland 16

Estuarine Forested Wetland 17 Estuarine Scrub/Shrub Wetland 18 Estuarine

Emergent Wetland 19 Unconsolidated Shore 20 Bare Land 21 Open Water 22

Palustrine Aquatic Bed 23 Estuarine Aquatic Bed 24 Tundra 25 Snow/Ice