can i delete temporary files from iCloud drive?

On my 2011 MacBook Pro running Yosemite, I have several documents and folders in iCloud Drive. I edit Numbers documents on my Mac and also on my iPad. On the Mac, there are system-created folders in addition to the documents, within the Numbers folder in iCloud Drive. The folder name corresponds to a filename within the Numbers folder, but has letters and numbers appended. Inside this folder is another folder titled "Metadata" which contains a "Properties.plist" file. There are also files titled "preview-micro.jpg", "preview-web.jpg" and "preview.jpg".

Here's my question: is it safe to delete this extra folder? I didn't create it, but it seems to be related to how the iPad would display the document. The folder is small, around 200 KB, but seems unnecessary. Is it?