Impact of heterogeneous ice nuclei on homogeneous freezing events in cirrus clouds
Impact of heterogeneous ice nuclei on homogeneous freezing events in cirrus clouds
复制标题
卷云中异质冰核对均质冻结事件的影响
DOI：
10.1029/2009jd012168
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发表时间：
2010
影响因子：
--
通讯作者：
D. Cziczo
中科院分区：
文献类型：
--
作者：
P. Spichtinger;D. Cziczo
[1]利用一个箱形模式研究了卷云中初始非均匀成核对随后均匀成核的影响，该模式包括气溶胶对冰晶成核的显式影响和一个新的沉降方案。不同的效果进行了讨论，即外部与内部混合物的异质冰核的影响和大小相关的冻结阈值的影响。进行了几个理想化的实验，这些实验表明，冰核外部混合物的处理可以强烈改变随后的均匀成核事件（即，冰晶数密度）在与对流层上部相关的各种环境条件下。在大多数情况下，观察到在随后的均匀冻结事件中形成的冰晶数浓度的强烈减少。与更简单的参数化相比，使用大小相关的冻结阈值可以改变云的特性，并且在最大的冰核浓度下是最重要的。
[1] The influence of initial heterogeneous nucleation on subsequent homogeneous nucleation events in cirrus clouds is investigated using a box model which includes the explicit impact of aerosols on the nucleation of ice crystals and a new sedimentation scheme. Different effects are discussed, namely the impact of external versus internal mixtures of heterogeneous ice nuclei and the influence of size-dependent freezing thresholds. Several idealized experiments are carried out, which show that the treatment of external mixtures of ice nuclei can strongly change subsequent homogeneous nucleation events (i.e., the ice crystal number densities) over a large variety of environmental conditions relevant for the upper troposphere. In most cases a strong reduction in ice crystal number concentrations formed in subsequent homogeneous freezing events is observed. The use of size-dependent freezing thresholds can change cloud properties when compared to more simple parameterizations and is most important at largest ice nuclei concentrations.