We describe an assimilation of thermal profiles below about 40 km altitude and total dust opacities into a general circulation model (GCM) of the Martian atmosphere. The data were provided by the Thermal Emission Spectrometer (TES) on board the Mars Global Surveyor (MGS) spacecraft. The results of the assimilation are verified against an independent source of contemporaneous data represented by...

[1] The rate at which the outgoing longwave radiation (OLR) responds to perturbations in temperature and moisture plays a fundamental role in determining climate sensitivity. This study examines the clear-sky OLR sensitivities to temperature and water vapor, as quantified by its partial derivatives (radiative Jacobians). The Jacobians, as computed by the Geophysical Fluid Dynamics Laboratory (G...

[1] This study explores the impact of spring subsurface soil temperature (SUBT) anomaly in the western U.S. on North American summer precipitation, mainly southeastern U.S., and possible mechanisms using a regional climate Eta model and a general circulation model (GCM). The GCM produces the lateral boundary condition (LBC) for the Eta model. Two initial SUBT conditions (one cold and another wa...

[1] The stability of the glacial thermohaline circulation (THC) with respect to North Atlantic freshwater input is examined using a global ocean general circulation model. It is found that the quasi-equilibrium hysteresis behaviour is much less pronounced under glacial conditions than under present-day conditions, and the existence of multiple equilibria requires an anomalous freshwater inflow....

[1] A 1 horizontal resolution North Atlantic general circulation model (GCM) in the latitude band 4.5 S to 39.5 N is compared to, and then combined with, chlorofluorocarbon and tritium transient tracer data. The method of Lagrange multipliers (adjoint) is used. Tracer distribution within the model ocean interior is primarily sensitive to the flux through the open northern boundary. This flux is...

Based on results from analytic and general circulation models, the authors propose a theory for the coupled warm pool, cold tongue, and Walker circulation system. The intensity of the coupled system is determined by the coupling strength, the local equilibrium time, and latitudinal differential heating. Most importantly, this intensity is strongly regulated in the coupled system, with a saturat...

An improved Bayesian optimal weighting scheme is developed and used to combine six atmospheric general circulation model (GCM) seasonal hindcast ensembles. The approach is based on the prior belief that the forecast probabilities of tercile-category precipitation and near-surface temperature are equal to the climatological ones. The six GCMs are integrated over the 1950–97 period with observed ...