A sensitivity theory for the equilibrium boundary layer over land
A sensitivity theory for the equilibrium boundary layer over land
复制标题
陆地平衡边界层的敏感性理论
DOI：
10.1002/jame.20048
复制
发表时间：
2013
影响因子：
6.8
通讯作者：
T. Cronin
中科院分区：
文献类型：
--
作者：
T. Cronin
由于与模拟陆-气相互作用相关的固有复杂性，全球模式通常使用复杂的陆面和边界层物理参数化。不幸的是，很难使用精细的模型，通过它们自己，来更深入地了解陆面参数如何影响耦合的陆-气系统。与此同时，更深入地了解土地覆被、土地利用和生态系统功能的变化作为过去和未来气候变化的作用力和反馈的作用也越来越重要。为了提高我们的理解的基础，我们概述了一个框架的边界层气候敏感性的基础上表面能量平衡;正如全球气候敏感性是基于顶部的大气能量平衡。我们发展了一个分析理论，用于分析陆地上一个日平均混合边界层的理想化模式的边界层气候敏感性。这种分析敏感性理论确定的土地表面的属性，包括水分供应，水分，空气动力学粗糙度的变化，强迫，并确定强负反馈与潜热和感热的表面通量。我们证明了我们的理论可以解释几乎所有的Betts（2000）方程组的灵敏度。该理论与双柱辐射对流模式模拟结果的有利比较表明，该理论可能广泛适用于统一我们对土地利用或生态系统功能变化如何影响气候变化的理解。
Due to the intrinsic complexities associated with modeling land‐atmosphere interactions, global models typically use elaborate land surface and boundary layer physics parameterizations. Unfortunately, it is difficult to use elaborate models, by themselves, to develop a deeper understanding of how land surface parameters affect the coupled land‐atmosphere system. At the same time, it is also increasingly important to gain a deeper understanding of the role of changes in land cover, land use, and ecosystem function as forcings and feedbacks in past and future climate change. To improve the foundation of our understanding, we outline a framework for boundary layer climate sensitivity based on surface energy balance; just as global climate sensitivity is based on top‐of‐atmosphere energy balance. We develop an analytic theory for the boundary layer climate sensitivity of an idealized model of a diurnally averaged well‐mixed boundary layer over land. This analytic sensitivity theory identifies changes in the properties of the land surface—including moisture availability, albedo, and aerodynamic roughness—as forcings, and identifies strong negative feedbacks associated with the surface fluxes of latent and sensible heat. We show that our theory can explain nearly all of the sensitivity of the Betts (2000) full system of equations. Favorable comparison of the theory and the simulation results from a two‐column radiative convective model suggests that the theory may be broadly useful for unifying our understanding of how changes in land use or ecosystem function may affect climate change.