The impacts of improved atmospheric absorption on radiative fluxes, atmospheric circulation, and hydrological cycle for long-term GCM integrations are investigated. For these runs the operational version of the Centro de Previsao de Tempo e Estudos Climáticos (CPTEC) AGCM and its enhanced version with a new solar radiation scheme are used. There is an 8% increase in the annual mean global average atmospheric absorption in the enhanced integration as compared with the operational model integration. The extra absorption is due to gases (0.5%), the water vapor continuum (1.5%), and background aerosols (6%), which were not considered in the operational solar radiation scheme. Under clear-sky conditions the enhanced model atmospheric absorption is in agreement with observations to within ±3 W m~(-2), while for all-sky conditions the remaining errors are related to unaccounted-for cloud absorption. There is a general warm-up of the atmosphere in the enhanced model with temperatures increasing up to 3 Kin the troposphere and 5–8 K in the stratosphere, bringing the model closer to the reference values. The intensities of the tropospheric jets are reduced by 7%–8%, while that of the polar night stratospheric jet is increased by 5%–10%, reducing the model systematic error. The reduced availability of latent energy for the saturated convective processes weakens the meridional circulation and slows down the hydrological cycle. The model overestimation of December–February precipitation over the SouthPacific convergence zone (SPCZ) and the South Atlantic convergence zone (SACZ) is reduced by 0.5–1.0 mm day~(-1), and that over the Northern Hemisphere storm-tracks region is reduced by 0.5 mm day~(-1). On a monthly time scale, the changes in the precipitation distribution over the SACZ are found to be much larger, ±2–3 mm day~(-1).
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机译：对于长期GCM积分，研究了改善的大气吸收对辐射通量，大气环流和水文循环的影响。对于这些运行，使用了临时温度估算中心（CPTEC）AGCM的操作版本及其带有新太阳辐射方案的增强版本。与运行模型集成相比，增强型集成中的全球平均年平均大气吸收量增加了8％。额外的吸收归因于气体（0.5％），水蒸气连续体（1.5％）和背景气溶胶（6％），在运行的太阳辐射方案中未考虑。在晴空条件下，增强的模型大气吸收与观测值一致，误差在±3 W m〜（-2）以内，而在全天空条件下，其余误差与无法解释的云吸收有关。增强型模型中的大气通常会升温，对流层中的温度升高到3 Kin，平流层中的温度上升到5-8 K，使模型更接近参考值。对流层射流的强度降低了7％–8％，而极地夜间平流层射流的强度提高了5％–10％，从而减小了模型的系统误差。饱和对流过程潜在能量的可利用性降低，从而削弱了子午环流并减慢了水文循环。南太平洋收敛带（SPCZ）和南大西洋收敛带（SACZ）12月至2月降水的模型高估减少了0.5–1.0 mm day〜（-1），而北半球风暴径区域的模型高估了减少了0.5毫米天〜（-1）。在每月的时间尺度上，在SACZ上的降水分布变化被发现要大得多，±2-3mm day〜（-1）。
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