We use the Massachusetts Institute of Technology general circulation model(GCM) dynamical core, in conjunction with a Newtonian relaxation scheme thatrelaxes to a gray, analytical solution of the radiative transfer equation, tosimulate a tidally locked, synchronously orbiting super-Earth exoplanet. Thishypothetical exoplanet is simulated under the following main assumptions: (1)the size, mass, and orbital characteristics of GJ 1214b (Charbonneau et al.,2009), (2) a greenhouse-gas dominated atmosphere, (3), the gas properties ofwater vapor, and (4) a surface. We have performed a parameter sweep over globalmean surface pressure (0.1, 1, 10, and 100 bar) and global mean surface albedo(0.1, 0.4, and 0.7). Given assumption (1) above, the period of rotation of thisexoplanet is 1.58 Earth-days, which we classify as the rapidly rotating regime.Our parameter sweep differs from Heng and Vogt (2011), who performed theirstudy in the slowly rotating regime and using Held and Suarez (1994) thermalforcing. This type of thermal forcing is a prescribed function, not related toany radiative transfer, used to benchmark Earth's atmosphere. An equatorial,westerly, superrotating jet is a robust feature in our GCM results. Thisequatorial jet is westerly at all longitudes. At high latitudes, the flow iseasterly. The zonal winds do show a change with global mean surface pressure.As global mean surface pressure increases, the speed of the equatorial jetdecreases between 9 and 15 hours local time (substellar point is located at 12hours local time). The latitudinal extent of the equatorial jet increases onthe nightside. Furthermore, the zonal wind speed in the equatorial andmidlatitude jets decreases with increasing surface albedo. Also, thelatitudinal width of the equatorial jet decreases as surface albedo increases.
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