Impact of stratospheric processes on climate variability and change in the troposphere

气候变率和变化通常是通过最先进的气候模式来理解和预测的。政府间气候变化专门委员会（IPCC）的气候模型模拟就是这样一个例子。在这些模式中，大气分量主要集中在对流层，对流层是大多数天气现象发生和大多数人为温室气体集中的地方。来自上方平流层（距地面约10公里至50公里）的影响常常被忽略。然而，最近的研究表明，平流层过程可以在很大程度上影响对流层环流。研究发现，如果没有真实的平流层，气候模式就不能再现北大西洋涛动的近期趋势，而北大西洋涛动在北美东北部和西欧的天气和气候系统中占主导地位。在南半球，已知地表气候直接受到平流层臭氧的影响。

Climate variability and changes have been often understood and predicted by means of state-of-the-art climate models. Such an example is climate model simulations for the Intergovernmental Panel on Climate Change (IPCC). In these models, the atmospheric component is primarily focused on the troposphere where most weather phenomena occur and most anthropogenic greenhouse gases are concentrated. The impact from the above, the stratosphere (from ~10 km to ~50 km above the ground), has often been ignored. Recent studies, however, have shown that stratospheric processes can influence the tropospheric circulation in a major way. It was found that, without realistic stratosphere, climate models can not reproduce recent trends in the North Atlantic Oscillation which dominates weather and climate systems over northeastern North America and western Europe. In the Southern Hemisphere, surface climate has been known to be directly affected by stratospheric ozone.