NASA Logo, National Aeronautics and Space Administration
LPVS website  banner

 

small LPV logo

Focus Area on Land Cover Product Validation


Sophie Bontemps, Université catholique de Louvain, Belgium
Alexandra Tyukavina, University of Maryland, USA

 


Land Cover Definition

Land cover is defined as the observed (bio)-physical cover on the Earth's terrestrial surface. It includes vegetation and man-made features as well as bare rock, bare soil and inland water surfaces (Di Gregorio, 2005).

Units:
The primary units for characterizing land cover are categories (e.g. Forest or Open Water) or continuous variables classifiers (fraction of Tree Canopy Cover). Secondary outputs include surface area of land cover types (hectares), land cover change (area and change trajectories) (GTOS, 2009).


Highest Validation Stage Currently Reached for Satellite-Derived Land Cover Products

Validation stage 4 (LPV validation stage hierarchy) - While most products are not validated higher than stage 3, recent efforts demonstrated that the validation stage 4 was achievable. The Copernicus global 100 m land cover maps (2015-2019) and the CCI Land Cover times series (1992-2018) were both operationall validated across years. This has been possible through the interpretation of very-high resolution reference data sets from multiple sources that were regularly updated over successive years. Global daily coverage of very high-resolution imagery is currently provided by commercial satellite constellations (RapidEye, SkySat, PlanetScope), which, if given wide access to the scientific community, will enable operational validation of products for more recent years. Limited access to these high-resolution datasets is provided through Planet Educational and Research programs and NASA's Commercial Smallsat Data Acquisition program. However, no consistent global coverage of very high-resolution data is available for historic mapping efforts (pre-2010)


Validation Good Practices

Land cover validation:

Strahler, A.H., Boschetti, L., Foody, G.M., Friedl, M.A., Hansen, M.C., Herold, M., Mayaux, P., Morisette, J.T., Stehman,    S.V. and C.E. Woodcock 2006. Global Land Cover Validation: Recommendations for Evaluation and Accuracy    Assessment of Global and Cover Maps. European Commission Joint Research Centre, Institute for Environment    and Sustainability. Scientific and Technical Research Series: EUR 22156 EN. 48 pp.

Land cover change validation:

Olofsson, P., Foody, G. M., Herold, M., Stehman, S. V., Woodcock, C. E. and Wulder, M. A. (2014). Good Practices for    Assessing Accuracy and Estimating Area of Land Change. Remote Sensing of Environment. 148:42-57.

Land Cover Validation Reference Data Sets:

Sourcebook, COP-22 version 1 GOFC-GOLD, 2016. A sourcebook of methods and procedures for monitoring and    reporting anthropogenic greenhouse gas emissions and removalsassociated with deforestation, gains and losses of    carbon stocks in forests remaining forests, and forestation. GOFC-GOLD Report version COP22-1, (GOFC-GOLD    Land Cover Project Office, Wageningen University, The Netherlands).


Land Cover Validation Reference Data Sets

Best currently available reference data for satellite-derived medium-resolution land cover product validation are based on higher-quality reference data, such as independent validation datasets and regional maps. Tsendbazar et al., 2014 reviewed existing land cover reference data sets and their suitability as function of the user community. With increasing resolution of future land cover products, the existing reference data sets will need further development.

GOFC-GOLD Reference Data Portal.


LPV Focus Areas

 

Meetings

IGARSS 2021, Special Session, CEOS Land Product Validation: Sampling-based estimation of area and accuracy for Land Cover products, Jul 11 -16, 2021, Brussels, Belgium

NASA Logo - nasa.gov