Precipitation is one of the major challenges in climate modeling. Among various factors, the large-scale atmospheric circulation plays an important role in modulating regional precipitation through dynamic processes that has been widely discussed in previous studies. However, few efforts have been made to investigate the relationship of model abilities to simulate precipitation and vector winds. Such an investigation may help to understand the source of uncertainty of precipitation simulation. Here, we examined the relationship between model performances in simulating precipitation with that in simulating vector winds by using the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Our results suggest that the model biases/uncertainties in simulating climatological mean precipitation often accompanied by the biases/uncertainties in vector wind fields. Model ability to simulate precipitation is closely related to the ability to simulate vector winds, especially over monsoon regions and the regions with warm and moist advection or high terrains, such as the South Asian and East Asian summer monsoon region, the Alaskan region, the Rocky Mountain, etc. Over these regions, the models with higher horizontal resolution tends to generate improved simulations in both the vector winds and precipitation relative to the models with coarse horizontal resolution. Besides, the model’s ability to simulate vector winds, compared to simulate the zonal wind, meridional wind, and skin temperature, is more closely related to the ability to simulate precipitation. This indicates that it is more meaningful to evaluate the vector winds than the zonal or meridional wind from the perspective of improving regional precipitation simulation.

降水是气候模拟中的主要挑战之一。在各种因素中，大规模的大气环流在通过动态过程调节区域降水中起着重要作用，这在先前的研究中已被广泛讨论。但是，很少有人努力研究模拟降水和矢量风的模型能力之间的关系。这样的调查可能有助于了解降水模拟不确定性的根源。在这里，我们使用耦合模型比较项目阶段5（CMIP5）模型研究了模拟降水和模拟矢量风之间模型之间的关系。我们的结果表明，在模拟气候平均降水量时，模型的偏差/不确定性通常伴随矢量风场中的偏差/不确定性。模拟降水的模型能力与模拟矢量风的能力密切相关，特别是在季风地区以及具有温暖湿润的平流或高地形的地区，例如南亚和东亚夏季风区域，阿拉斯加地区，落基山脉在这些区域上，相对于具有较粗水平分辨率的模型，具有较高水平分辨率的模型倾向于在矢量风和降水方面生成改进的模拟。此外，与模拟纬向风，子午风和皮肤温度相比，模型具有矢量风的模拟能力，与模拟降水的能力更紧密相关。这表明，从改进区域降水模拟的角度来看，评估矢量风比纬向或经向风更有意义。