Thematic accuracy assessment of the NLCD 2016 land cover for the conterminous United States

The primary goal of thematic accuracy assessment is to measure the quality of land cover products and it has become an essential component in global or regional land cover mapping. However, there are many uncertainties introduced in the validation process which could propagate into the derived accuracy measures and therefore impact the decisions made with these maps. Choosing the appropriate reference data sample unit is one of the most important decisions in this process. The majority of researchers have used a single pixel as the assessment unit for thematic accuracy assessment, while others have claimed that a single pixel is not appropriate. The research reported here shows the results of a simulation analysis from the perspective of positional errors. Factors including landscape characteristics, the classification scheme, the spatial scale, and the labeling threshold were also examined. The thematic errors caused by positional errors were analyzed using the current level of geo-registration accuracy achieved by several global land cover mapping projects. The primary results demonstrate that using a single-pixel as an assessment unit introduces a significant amount of thematic error. In addition, the coarser the spatial scale, the greater the impact on positional errors as most pixels in the image become mixed. A classification scheme with more classes and a more heterogeneous landscape increased the positional effect. Using a higher labeling threshold decreased the positional impact but greatly increased the number of abandoned units in the sample. This research showed that remote sensing applications should not employ a single-pixel as an assessment unit in the thematic accuracy assessment.

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Thematic accuracy assessment of the 2011 National Land Cover Database (NLCD)

Remote Sensing of Environment ◽

10.1016/j.rse.2016.12.026 ◽

2017 ◽

Vol 191 ◽

pp. 328-341 ◽

Cited By ~ 92

Author(s):

James Wickham ◽

Stephen V. Stehman ◽

Leila Gass ◽

Jon A. Dewitz ◽

Daniel G. Sorenson ◽

...

Keyword(s):

Land Cover ◽

Accuracy Assessment ◽

Thematic Accuracy

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Thematic accuracy of the 1992 National Land-Cover Data for the eastern United States: Statistical methodology and regional results

Remote Sensing of Environment ◽

10.1016/s0034-4257(03)00128-7 ◽

2003 ◽

Vol 86 (4) ◽

pp. 500-516 ◽

Cited By ~ 133

Author(s):

S.V. Stehman ◽

J.D Wickham ◽

J.H. Smith ◽

L. Yang

Keyword(s):

United States ◽

Land Cover ◽

Eastern United States ◽

Statistical Methodology ◽

Land Cover Data ◽

Thematic Accuracy

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VALIDATION OF THE GLOBAL HIGH-RESOLUTION GLOBELAND30 LAND COVER MAP IN EUROPE USING LAND COVER FIELD SURVEY DATABASE - LUCAS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-4-51-2018 ◽

2018 ◽

Vol XLII-4 ◽

pp. 51-59

Author(s):

G. Bratic ◽

M. E. Molinari ◽

M. A. Brovelli

Keyword(s):

High Resolution ◽

Land Cover ◽

Field Survey ◽

Accuracy Assessment ◽

Ground Truth ◽

Small Region ◽

Gis And Remote Sensing ◽

High Level ◽

Thematic Accuracy ◽

Land Cover Maps

Abstract. High-resolution land cover maps are one of the technological innovations driving improvements in many fields influenced by Geographic Information Systems (GIS) and Remote Sensing. In particular, the GlobeLand30 (GL30), global LC map with spatial resolution of 30m, is thought to be one of the highest quality high-resolution products. However, these LC maps require validation to determine their suitability for a particular purpose. One of the best ways to provide useful validation reference data is to do a high-level accuracy field survey, but this is time consuming and expensive. Another option is to exploit already available datasets. This study assesses thematic accuracy of GL30 in Europe using LUCAS as a validation reference, because it is a free and open field survey database. The results were generally not good, and very bad for some classes. Analysis was then restricted to a small region (Lombardy, Italy) where LC data of higher resolution than those of GL30 were available. LUCAS was also found to be incoherent with this product. Further comparisons of LUCAS with other independent sources confirmed that the LC attributes of LUCAS are inconsistent with expectations. Although these findings may not be generalized to other regions, the results warn against the suitability of LUCAS as ground truth for LC validation. The paper discusses the process of thematic accuracy assessment of the GL30 and the applicability of LUCAS for high-resolution global LC validation.

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