I thought the mods would have closed the thread. But since they didn't I'll repost. The picture is taken looking south as opposed to looking west. I initially thought it was taken looking west. So according to Google earth the length of the stretch of islands on the horizon (from left to right or right to left) is about 105 miles.
In the first picture we can see Corsica all the way to Isola d'Elba. Again, the distance from one end of the island to the other is about 105 miles.

If the earth is a globe and is 25,000 english statue miles in circumference, the surface of all standing water must be convex at some degree -- every part must be an arc of a circle. From the peak or summit of any such arc there will exist a curvature of declination of 8 inches in the first statue mile. In the second mile the fall will be 32 inches; in the third mile it will be 72 inches or 6 feet and so on.
https://plus.google.com/u/0/photos/103813706899664739158/albums/6169277669745624769/6169277670769305218?sqi=110948746616556574259&sqsi=7777574a-d00e-4b07-9214-6b5372d44913At the center of the x axis or horizontal line would be the summit of an arc of a circle being 52.5 miles (half of 105 miles) from each end, and would stand more than 1838 feet above.
Now read the following very carefully, okay? Let's forget about the Z axis or the distance from the observer to the island. Let's focus on the x axis or the horizontal line (where the base of the islands meet the ocean). If the earth was a globe, the x axis or the horizontal line would have VERY apparent, discernible curvature. How do I know this? Again, the middle of photo at the x axis would be the summit of an arc of a circle and should drop at least half of 1838 feet onto the far left and onto the far right.
But get this, the peak elevation of Corsica is 8,878 feet! So surely if you can see 8,878 feet from the base of the island to its peak in the picture then you would see 1838 feet (21% of 8,878 feet) of curvature or declination on the x axis from the center to the left and to the right.
As a matter of fact, the x axis or the horizontal line stretching 105+ miles is as straight as a ruler!!!

Possible if the earth was a globe at 25,000 statute miles of circumference?
The x axis or the horizon line should look like this to some degree
http://www.sacred-texts.com/earth/za/img/fig20.jpghttp://www.sacred-texts.com/earth/za/img/fig22.jpgBut it looks like this
http://www.sacred-texts.com/earth/za/img/fig19.jpghttp://www.sacred-texts.com/earth/za/img/fig21.jpg