理想化GCM中的水汽浮力反馈
Vapor-Buoyancy Feedback in an Idealized GCM
AI总结：
本研究利用理想化GCM实验证实水汽浮力（VB）会使热带自由对流层增暖、提升出射长波辐射，形成随气候变暖增强的负VB反馈，且该反馈在考虑行星自转、云及抵消性水汽反馈时仍保持稳健。
摘要：
在相同温度和压强下，湿空气比干空气轻，这是因为水汽的分子量小于干空气的分子量，该效应被称为水汽浮力（vapor buoyancy, VB）。本研究利用理想化大气环流模式（general circulation model, GCM）开展实验，证明VB会使热带自由对流层增暖，并导致出射长波辐射（outgoing longwave radiation, OLR）显著增加。该辐射效应随气候变暖而增强，在该区域形成负气候反馈，我们将其称为VB反馈。尽管VB反馈最早在简化模型中得到证实，但此前尚不清楚该反馈是否会受行星自转、云或抵消性水汽反馈的显著削弱。然而，我们的GCM模拟结果显示，在考虑这些因素的情况下，VB反馈依然稳健且保持相当的强度。
英文摘要：
Humid air is lighter than dry air at the same temperature and pressure because the molecular weight of water vapor is less than that of dry air. This effect is known as vapor buoyancy (VB). In this work we use experiments in an idealized general circulation model (GCM) to show that VB warms the tropical free troposphere and leads to a significant increase in outgoing longwave radiation (OLR). This radiative effect increases with climate warming, causing a negative climate feedback there. We call this the VB feedback. Although this VB feedback was first corroborated in simplified models, it was heretofore unclear whether the VB feedback is significantly impaired by planetary rotation, clouds, or a countervailing water vapor feedback. However, our GCM simulations show that the VB feedback is robust and maintains an appreciable magnitude when considering these factors.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
