that is called a T-top.
quote from wiki:
"Targa top, targa for short, is a
semi-convertible car body style with a removable roof section and a
full width roll bar behind the seats. The rear window can be fixed
or removable, making it a convertible. In common usage, any piece
of metal or trim which rises up from the side of a car and
continues in an uninterrupted line over the roof and down the other
side may be called a targa band, or sometimes a wrapover band.
Targa tops are different from T-tops, which have a solid,
non-removable bar running between the top of the windshield and the
rear roll-bar."
