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(Abridged) We report results of three dimensional MHD simulations of globalaccretion disks threaded with weak vertical magnetic fields. We perform thesimulations in the spherical coordinates with different temperature profilesand accordingly different rotation profiles. In the cases with a spatiallyconstant temperature, because the rotation frequency is vertically constant inthe equilibrium condition, general properties of the turbulence arequantitatively similar to those obtained in local shearing box simulations. Onthe other hand, in the cases with a radially variable temperature profile, thevertical differential rotation, which is inevitable in the equilibriumcondition, winds up the magnetic field lines, in addition to the usual radialdifferential rotation. As a result, the coherent wound magnetic fieldscontribute to the Maxwell stress in the surface regions. We obtainnondimensional density and velocity fluctuations ~0.1-0.2 at the midplane. Theazimuthal power spectra of the magnetic fields show shallow slopes, ~m^0-m^{-1}, than those of velocity and density. We observe intermittent andstructured disk winds driven by the Poynting flux associated with the MHDturbulence. The Poynting flux originating from magnetic tension is injectedfrom the regions above a scale height towards both the midplane and thesurfaces. Related to this, sound waves are directed to the midplane from thesurface regions. The mass accretion mainly occurs near the surfaces and the gasnear the midplane slowly moves outward, which causes large-scale meridionalcirculations. The vertical magnetic fields are also dragged inward in thesurface regions, while they stochastically move outward and inward around themidplane. We also discuss an observational implication of induced spiralstructure in the simulated turbulent disks to protoplanetary disks.

MHD Simulations of Global Accretion Disks with Vertical Magnetic Fields