How can I shut it down?

From semantic-mediawiki.org

Looks like you need to run SMW_refreshData.php.

03:19, 18 December 2013

Actually, I think you'll have to rename the property. As you've seen, SMW has weird handling for properties that have the same name as types - I think it's silly, but that's how it is. What about "Has temperature"?

02:37, 20 December 2013