Atmospheric Dynamics of Short-Period Extrasolar Gas Giant Planets. I. Dependence of Nightside Temperature on Opacity

摘要: More than two dozen short-period Jupiter-mass gas giant planets have been discovered around nearby solar-type stars in recent years, several of which undergo transits, making them ideal for the detection and characterization their atmospheres. Here we adopt a three-dimensional radiative hydrodynamical numerical scheme to simulate atmospheric circulation on close-in planets. In contrast conventional GCM shallow water algorithms, this method does not assume quasi-hydrostatic equilibrium, it approximates radiation transfer from optically thin thick regions with flux-limited diffusion. first paper series, consider synchronously spinning giants. We show that full treatment, coupled rotationally modified flows an accurate treatment radiation, yields clear temperature transition at terminator. Based series simulations varying opacities, nightside is strong indicator opacity planetary atmosphere. Planetary atmospheres maintain large interstellar opacities will exhibit day-night differences, while reduced due extensive grain growth sedimentation much more uniform temperatures throughout photospheres. addition results, present four-zone analytic approximation explain dependence.