iNaturalist was using Google Maps API on displaying locations.
In mainland China, because of the Restriction on geographic data (see https://en.wikipedia.org/wiki/Restrictions_on_geographic_data_in_China for reference), the satellite map is using the default (true) WGS-84 grid system, while the vector map is using a GCJ-02 grid system, which creates an offset between 50-500 meters from its satellite imagery. This is toleratable because we can simply use sat image to prevent the offset from the observation positions (which is generated with the GPS).
However, since a few days ago, we find that the satellite map on iNat also adapts the GCJ-02 system, therefore BOTH the satellite AND vector maps are now have the offset with the GPS thus the observation positions (OSM remains accurate). And we find ONLY Simplified Chinese users (account Language/Locale set to 简体中文=simplified Chinese) are proned to this update. Both Android and Web are affected.
Is this map grid update deliberate (i.e. compliance to Chinese authority regulations) or unintentional (e.g. some issues from the map API provider)? It has made Chinese users more difficult to determine the position of our observations inside mainland China.
This is a Google issue and not an iNat issue.
From Google:
All maps created for mainland China must follow the GCJ-02 coordinate system
This has been the case since 2006. I think until recently google was getting away with keeping the imagery portion WGS84 (actually Google uses Web Mercator, not WGS84, but that’s a different topic), but recently China may have forced compliance for the imagery portion as well. This may be due to changes with their Chinese partner AutoNavi. Google is not allowed to show Chinese map data without it being provided by a local partner, which the Chinese government decided as AutoNavi. It may not be so much Google changing the map, but their partner in China changing it.
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