| 模型ID： | M00026 | ||||||
| 模型名称： | 一维大气微波辐射传输模型 | ||||||
| 模型编码者： |
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| 模型关键字： | 大气、微波、辐射传输、微波辐射计 | ||||||
| 模型类型： | 理论模型 | ||||||
| 模型最后修改日期： | 2014/3/29 0:00:00 | ||||||
| 模型提交日期： | 2014/3/29 0:00:00 | ||||||
| 模型摘要： | 模型通过自定义输入大气廓线数据（包括大气高度廓线、大气压强廓线、大气温度廓线、大气湿度廓线、大气水汽廓线、云以及其他大气水凝物廓线）、微波辐射计参数（包括频率波段信息、入射角度信息等）地表发射和反射信息以及宇宙背景辐射等信息后可以模拟大气顶层传感器所接收的辐射亮度信息。模型中在输入下垫面地表发射和辐射信息时，也可以由其他的地表发射或模型来提供，这样便可以形成一个由地表发射模型和大气辐射传输模型组成的综合的微波辐射传输模型，便于从整体上分析微波信号与地表和大气的相互作用。此版本可以微波辐射计AMSR-E观测的亮温。 | ||||||
| 公式： |
| 1 |
名称：地表温度
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参数类型：double
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物理意义：地表温度，（单位：K）
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| 2 |
名称：地表发射率
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参数类型：double
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物理意义：与AMSR-E各个频段对应的地表发射率
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| 3 |
名称：大气廓线分层数量
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参数类型：double
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物理意义：大气廓线分层数量
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| 4 |
名称：大气廓线
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参数类型：double
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物理意义：大气廓线，包括：（高程、相对湿度、温度、气压、云中液态水、降雨率、冰、雪、雪丸、冰雹等廓线）
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| 标题： | A melting-layer model for passive/active microwave remote sensing applications. Part I: Model formulation and comparison with observations | ||||||||||||||||||||||||
| 文献作者： |
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| 文献引用： | Journal of Applied Meteorology | ||||||||||||||||||||||||
| 文献摘要: | In this study, a 1D steady-state microphysical model that describes the vertical distribution of melting precipitation particles is developed. The model is driven by the ice-phase precipitation distributions just above the freezing level at applicable grid points of “parent” 3D cloud-resolving model (CRM) simulations. It extends these simulations by providing the number density and meltwater fraction of each particle in finely separated size categories through the melting layer. The depth of the modeled melting layer is primarily determined by the initial material density of the ice-phase precipitation. The radiative properties of melting precipitation at microwave frequencies are calculated based upon different methods for describing the dielectric properties of mixed-phase particles. Particle absorption and scattering efficiencies at the Tropical Rainfall Measuring Mission Microwave Imager frequencies (10.65–85.5 GHz) are enhanced greatly for relatively small (0.1) meltwater fractions. The relatively large number of partially melted particles just below the freezing level in stratiform regions leads to significant microwave absorption, well exceeding the absorption by rain at the base of the melting layer. Calculated precipitation backscatter efficiencies at the precipitation radar frequency (13.8 GHz) increase with particle meltwater fraction, leading to a “bright band” of enhanced radar reflectivities in agreement with previous studies. The radiative properties of the melting layer are determined by the choice of dielectric models and the initial water contents and material densities of the “seeding” ice-phase precipitation particles. Simulated melting-layer profiles based upon snow described by the Fabry–Szyrmer core-shell dielectric model and graupel described by the Maxwell-Garnett water matrix dielectric model lead to reasonable agreement with radar-derived melting-layer optical depth distributions. Moreover, control profiles that do not contain mixed-phase precipitation particles yield optical depths that are systematically lower than those observed. Therefore, the use of the melting-layer model to extend 3D CRM simulations is likely justified, at least until more-realistic spectral methods for describing melting precipitation in high-resolution, 3D CRMs are implemented. |
模型公式