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Douglas L. Brooks

210.JOURNAL OF METEOROLOGYVOLUME 15THE DISTRIBUTION OF CARBON DIOXIDE COOLING IN THE LOWER STRATOSPHEREBy Douglas L. BrooksOperations Evaluation Group, Massachusetts Institute of Technology(Manuscript received 29 August 1957) . ABSTMCTThe distribution of radiational cooling due to carbon dioxide is computed for the stratosphere below 30 kmin an effort to provide an insight into the role of radiation in the observed seasonal and latitudinal changesof temperature and flow. Laboratory

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Johnny Wei-Bing Lin, J. David Neelin, and Ning Zeng

as a possible source of variance for maintaining the MJO. GCM studies of tropical intraseasonal variance use cumulus parameterizations that simulate the mean effects of subgrid convection but do not explicitly model the subgrid convective variance (such as those associated with mesoscale systems). However, there are indications that such small-scale effects could feed back onto the large scale. Salby and Garcia (1987) found that a stochastic convective heating source with seasonal variability

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Lawrence N. Lahiff

region, 2) the ITCZconvective region, 3) the outflow region, and 4) a subsidence region. The mixed layer ocean has variabledepth and temperature. Fluxes of heat, momentum and moisture to the mid-latitudes by longitudinallydependent eddies are parameterized. Evaporative and sensible heat fluxes from the surface are included.Condensation occurs in the ITCZ. Solar and terrestial radiative diabatic effects are predicted by use of aslab radiation model. Seasonal variations of the solar heating are

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David A. Randall, Harshvardhan, and Donald A. Dazlich

based on comparison of threenondiurnal June-July integrations with three Julys from a multiyear diurnally forced seasonal simulation. Theresults show major changes in the time-averaged surface enet~ budget, and much more predpitatiou in"summermonsoon" regimes when the diurnal cycle is omitted.1. Introduction Observations show strong diurnal and semidiurnaloscillations in precipitation, mainly in the tropics andthe summer hemisphere (e.g., Hamilton 198 la). Theseoscillations are most prominent

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Murry L. Salby, Rolando R. Garcia, Donal O'sullivan, and Patrick Callaghan

, a sizable flux of potential vorticity results there from diabatic effects acting on large scales. Thisnondispersive source of eddy Q flux is analogous to thermal dissipation of planetary waves and may representan important source of error in meridional diffusivities calculated from eddy potential vorticity flux. Eddy stirring weakens the mefidional gradient of Q at low latitudes. However, thermal drive restores thegradient after episodes of mixing. Variations in the tropical Q gradient are

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Gary K. Corlett and Paul S. Monks

, there are clear latitudinal variations to the observed differences between TOVS, TOMS, and GOME ozone column values. To test for seasonal dependency, the datasets were averaged into 3-month (seasonal) blocks covering January–March, April–June, July–September, and October–December. One example of this analysis is shown in Fig. 3 , for the period January–March averaged over all 4 yr. It is apparent that two of the trends observed previously, low readings from GOME in the Southern Hemisphere and high

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Ka Ming W. Lau

1144 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME35Experiment with a Simple Ocean-Atmosphere Climate Model: The Role of the Ocean in the Global Climate KA MING W. I,AU~Departrnera of Atmospheric S-ion~es, Uni~erslty o)t Washington, Seattle 98195(Manuscript received 9 December 1977, in final form 9 March 1978)ABSTRACT A study of the seasonal variation of the climatic states of the

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Kevin Hamilton

propagating equatorial waves by the large-scale tropospheric circulation; see Maruyama and Tsuneoka (1988) and Geller et al. (1997) ]. The present experiment, in which the imposed forcing is restricted to the stratosphere, allows for a clear determination of any tropospheric effects of stratospheric forcing. This is a subject of possible practical importance for seasonal weather forecasting, since the tropical QBO itself is clearly predictable with some skill out to periods of months or even years. A

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Edwin P. Gerber

tropospheric circulations through downward control. The negative effects are most pronounced in “low top” models with an upper boundary within the stratosphere (e.g., 10 hPa), as documented by Shaw et al. (2009) . Aware of this potential weakness in our model, we have taken care to ensure that all the results in this study are not affected by the upper boundary condition. Table 1 lists the integrations used in this study. All were integrated for 10 000 days after a 300-day spinup period. Circulation

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Illia Horenko

values for the seasonal trend model (dashed lines) and the local Gaussian kernel smoothing result (dashed–dotted); note that the effective Gaussian window width of 10 yr corresponds to the Gaussian window width used in the original work ( Jones et al. 1993 ) considering the analysis of the U.K. Lamb index series. This finding means that the influence of seasonal pattern variability on transition processes is dominated by the long-term effects induced by the single polynomial trend and hidden

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