When I search Google.com from Canada I often see .UK results in the SERPs on Google. If I switch google.ca the results are gone. Or if I use a US based machine the UK results are also gone. So Google clearly knows that I am not in the US when I use google.com. Why does Google.com think that .uk results are relevant to a Canadian.

NOTE: For testing I use a browser with all cookies cleared and I am not signed into my Google account.

I have a preference for Google.com v. Google.ca.

Here are some screen shots of results that show .uk results in Google.com.