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The light pollution map has two base layers (road and hybrid Bing maps), light pollution radiance overlays and the user light pollution measurements overlay.
To add your SQM measurements turn on the "User SQM" overlay in "SQM overlay & filter" menu and click on the pencil icon in the toolbar. "SQM overlay & filter" menu also contains filters to limit the display of SQM measurements.
The light pollution 2010 overlay was made from "Version 4 DMSP-OLS Stable Lights Coverage".
The light pollution 2014, 2015, 2016 overlays were made from "VIIRS DNB Cloud Free Composites".
Data from 2010 and 2014/2015/2016 is not comparable (different satellite systems)!!!
Annual VIIRS comparisons are also to be avoided as there are too many factors involved by just doing a direct comparison.