ETC DI Report 2024/3 Analysis of usability of Imperviousness and CLC+ Backbone data for mapping sealed areas

13 Jun 2024

Gergely Maucha (Lechner Ltd.), Éva Kerékgyártó (Lechner Ltd.), Viktória Turos (Lechner Ltd.), Christophe Sannier (GAF), Jaroslav Dufek (GISAT), Tomas Soukup (GISAT), Eva Ivits (EEA)

For EU policies to be efficiently planned, there is a need for a continental, harmonized, multitemporal and highly detailed indicator on soil sealing that allows the monitoring of the location and the degree of impacts.


The European Copernicus Land Monitoring Service has been producing datasets on imperviousness every 3 years since 2006, which are the only high-resolution datasets that enable European wide monitoring. However, after the 2015 reporting year, the input for the production of the imperviousness dataset was switched from mixed inputs to the European Sentinel satellites. While this led to an improvement in the spatial detail from 20 m to 10 m, the change in the input dataset also resulted in a break in the time series as the 2018 update was not comparable to the previous reference years.


Above issues have raised a discussion on statistical relevancy and appropriate use of areal statistics generated from CLMS products. To address these issues, we present a detailed analysis of similarities and differences in the specifications of sealing related CLMS datasets, as well as providing practical comparisons of sealed area estimations.


Based on the results of the analysis, a practical solution is presented in the form of a harmonized and bias-corrected continental soil sealing dataset for Europe for the entire observation period. This new dataset has been validated to be the best current dataset for monitoring imperviousness and soil sealing impacts as a direct input for European policies.