A microphysics guide to cirrus clouds – Part 1: Cirrus types
A microphysics guide to cirrus clouds – Part 1: Cirrus types
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DOI：
10.5194/acp-16-3463-2016
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发表时间：
2015-11
影响因子：
6.3
通讯作者：
M. Krämer;C. Rolf;A. Luebke;A. Afchine;N. Spelten;A. Costa;Jessica R. Meyer;M. Zöger;Jessica B. S
中科院分区：
文献类型：
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作者：
M. Krämer;C. Rolf;A. Luebke;A. Afchine;N. Spelten;A. Costa;Jessica R. Meyer;M. Zöger;Jessica B. S
抽象的。卷云的微物理和辐射特性仍然令人费解，因此仍然是预测地球气候的最大不确定性之一(气专委，2013年)。我们的研究旨在为卷云微物理提供指导，该微物理是从一系列广泛的模式模拟汇编而成的，涵盖了卷云形成和演化的广泛大气条件。模型结果在与现场测量相同的参数空间中描述，即在IWC-T参数空间中描述。我们通过评估过去15年中进行的17次飞机活动的卷云数据集来验证这种卷云分析方法，这些飞机在欧洲、澳大利亚、巴西以及南美洲和北美上空花费了大约94小时的卷云。总之，本研究的方法是通过模式模拟来跟踪卷云IWC的发展随温度的变化，并与观测结果进行比较，然后在一定程度上将卷云微物理赋予观测。事实上，现场观测显示了模拟的卷云指南所预期的特征。例如，高(低)IWC与高(低)冰晶浓度一起被发现尼斯。我们研究的一个重要发现是对两种不同形成机制和微物理性质的卷云进行了分类：第一种卷云直接形成为冰(原地起源卷云)，并根据上升气流的普遍强度分成两个亚类：在缓慢上升气流中，这些卷云较薄，具有较低的IWC，而在快速上升气流中，可以形成较厚的IWC较高的卷云。第二类主要是来自混合相云的厚卷云(即通过冻结液滴-液源卷云)，它们在上升到卷云形成温度区域时完全冰化(
Abstract. The microphysical and radiative properties of cirrus clouds continue to be beyond understanding and thus still represent one of the largest uncertainties in the prediction of the Earth's climate (IPCC, 2013). Our study aims to provide a guide to cirrus microphysics, which is compiled from an extensive set of model simulations, covering the broad range of atmospheric conditions for cirrus formation and evolution. The model results are portrayed in the same parameter space as field measurements, i.e., in the Ice Water Content-Temperature (IWC-T) parameter space. We validate this cirrus analysis approach by evaluating cirrus data sets from 17 aircraft campaigns, conducted in the last 15 years, spending about 94 h in cirrus over Europe, Australia, Brazil as well as South and North America. Altogether, the approach of this study is to track cirrus IWC development with temperature by means of model simulations, compare with observations and then assign, to a certain degree, cirrus microphysics to the observations. Indeed, the field observations show characteristics expected from the simulated Cirrus Guide. For example, high (low) IWCs are found together with high (low) ice crystal concentrations Nice. An important finding from our study is the classification of two types of cirrus with differing formation mechanisms and microphysical properties: the first cirrus type forms directly as ice (in situ origin cirrus) and splits in two subclasses, depending on the prevailing strength of the updraft: in slow updrafts these cirrus are rather thin with lower IWCs, while in fast updrafts thicker cirrus with higher IWCs can form. The second type consists predominantly of thick cirrus originating from mixed phase clouds (i.e., via freezing of liquid droplets – liquid origin cirrus), which are completely glaciated while lifting to the cirrus formation temperature region (