I don't think that there is SE site for your question.
Web Applications could be the closest site, as the question is about a Google web app, but the scope of this site is about using a web application, not about the data sources per se. Maybe you could make a related question like where to check the data source of an specific query / result as Google could use several data sources as they love to "personalize" results, i.e. they could use different data sources for different cities due to any criteria that they want to use, like relevance, user rating, costs, A/B testing.
Earth Science has a some way related questions: