Algebraic construction of a Nambu bracket for the two-dimensional vorticity equation

► Generalized Hamiltonian fluid mechanics for the two-dimensional vorticity equation. ► Enstrophy as Casimir of the Zeitlin (sine-bracket) truncation. ► Algebraic construction of Nambu bracket by Bialynicki-Birula and Morrison method. ► Infinite-mode limit yields continuum Nambu bracket. ► Discussion of generalized Jacobi identity.