论文标题
降水效率通过增强热带循环放缓和东部太平洋变暖来增强气候灵敏度
Precipitation efficiency amplifies climate sensitivity by enhancing tropical circulation slowdown and eastern pacific warming
论文作者
论文摘要
云过程是量化全球温度对二氧化碳升高的响应的最大不确定性来源。尽管如此，降水效率（PE）的作用 - 每单位柱的表面降雨 - 综合凝结 - 尚未量化。在这里，我们使用36个有限域的云解决模拟，从辐射感染的平衡模型对比项目中，表明它们强烈暗示气候变暖将导致净降水效率提高。然后，我们分析了从耦合模型对比项目6中分析35个通用循环模型（GCM），发现增加的PE可以增强热带循环的放缓并增强东部赤道太平洋的变暖。这些变化通过引起层状弧形云降低和层状抑制，从而触发泛带云的反馈，从而扩大总体气候灵敏度。定量地，我们发现，在35个GCM中，有24个与云分辨模型相匹配，以模拟PE与温室变暖增加，平均有效的气候灵敏度比PE降低的GCM高1 k。模拟增加PE的模型还包含4 K上有效气候灵敏度的所有估计值。总之，这些结果表明，对PE对变暖的敏感性进一步限制将减少对未来气候变化的不确定性。
Cloud processes are the largest source of uncertainty in quantifying the global temperature response to carbon dioxide rise. Still, the role of precipitation efficiency (PE) -- surface rain per unit column -- integrated condensation -- is yet to be quantified. Here we use 36 limited-domain cloud resolving simulations from the Radiative-Convective Equilibrium Model Intercomparison Project to show that they strongly imply climate warming will result in increases to net precipitation efficiency. We then analyze 35 General Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase 6 and find that increasing PE enhances tropical circulation slowdown and strengthens eastern equatorial Pacific warming. These changes trigger pan-tropical positive cloud feedback by causing stratiform anvil cloud reduction and stratocumulus suppression, and thereby amplify overall climate sensitivity. Quantitatively, we find that in the 24 of 35 GCMs which match the cloud-resolving models in simulating increasing PE with greenhouse warming, mean Effective Climate Sensitivity is 1 K higher than in GCMs in which PE decreases. The models simulating increasing PE also comprise all estimates of effective climate sensitivity over 4 K. Taken together, these results show that further constraining PE sensitivity to warming will reduce uncertainty over future climate change.
