Brighton's web site states,
Afloat is a huge circular donut shaped globe cast in bronze. Situated at the seaward end of the groyne, its centre at eye level allows a view of our world through the sculpture.
The donut or torus (a shape that has a continuous surface with a hole in it) has been posed as a possible model by scientists of how our universe may look. The sculpture was generated by taking a world globe and pressing the south and north poles together to form a torus. Now placed on its side the lines of longitude radiate from the central hole, linking the sea and sky. Across its surface are the shrunken shapes of the major continents, adrift like dark shadows. Brighton & Hove City Council