Future Changes in the Brewer–Dobson Circulation under Different Greenhouse Gas Concentrations in WACCM4
Future Changes in the Brewer–Dobson Circulation under Different Greenhouse Gas Concentrations in WACCM4
复制标题
WACCM4 中不同温室气体浓度下布鲁尔-多布森环流的未来变化
DOI：
10.1175/jas-d-13-0289.1
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发表时间：
2014
影响因子：
3.1
通讯作者：
R. Garcia
中科院分区：
文献类型：
--
作者：
F. Palmeiro;N. Calvo;R. Garcia
利用与海洋模式完全耦合的最新版本的全大气社区气候模式（WACCM 4），研究了3种气候变化情景下布鲁尔多布森环流（BDC）的气候学和未来变化。结果表明，随着温室气体的增加，环流的浅支和深支都有加速的趋势，同时平流层顶附近的深分支中热带上升流也有向上的位移。向下控制原理揭示了在迫使上下分支加速时，涉及到不同的twins。气候平均热带上升流在平流层的下部和上部的主要明确解决，行星尺度波。在平流层下部的热带上升流趋势主要归因于明确解决，行星尺度波。然而，在平流层上部，尽管事实上，解决波控制气候上升流的强迫，其贡献的长期趋势减少与增加温室气体，而与锋的作用增加，并成为主导模式的温室气体增加最大的情景。由于气候变化，副热带对流层急流的加强和向上位移导致锋面重力波谱的西部过滤，使东风分量到达平流层上部，迫使那里的环流发生变化。
The climatology and future changes of the Brewer‐Dobson circulation (BDC) in three climate change scenarios are studied using the latest version of the Whole Atmosphere Community Climate Model (WACCM4), which is fully coupled to an ocean model. The results show an acceleration in both the shallow anddeepbranchesofcirculationin responsetoincreasinggreenhousegases(GHGs)togetherwith anupward displacement of the tropical upwelling in the deep branch near the stratopause. The downward control principlerevealsthatdifferentwavesareinvolvedin forcingtheaccelerationoftheupperandlowerbranches. Climatological-mean tropical upwelling in both the lower and upper stratosphere is dominated by explicitly resolved, planetary-scale waves. Trends in the tropical upwelling in the lower stratosphere are mainly attributedtoexplicitlyresolved,planetary-scalewaves.However,intheupperstratosphere,despitethefactthat resolved waves control the forcing of the climatological upwelling, their contribution to the long-term trend diminishes with increasing GHGs, while the role of gravity waves associated with fronts increases and becomes dominant in the model scenario with the largest GHG increases. The intensification and upward displacementofthesubtropicaltroposphericjetsduetoclimatechangeleadstofilteringofthewesterlypartof the frontal gravity wave spectrum, leaving the easterly components to reach the upper stratosphere and force the changes in the circulation there.