| 有云环境下MODIS亮温资料的变分同化Ⅰ——方案设计与理想试验 |
| |
| 引用本文： | 丁伟钰,万齐林,张诚忠,陈子通,黄燕燕.有云环境下MODIS亮温资料的变分同化Ⅰ——方案设计与理想试验[J].热带气象学报,2009,25(6):649-659. |
| |
| 作者姓名： | 丁伟钰 万齐林 张诚忠 陈子通 黄燕燕 |
| |
| 作者单位： | 中国气象局广州热带海洋气象研究所,广东,广州,510080 |
| |
| 基金项目： | 国家重点基础研究发展计划资助，广东省自然科学基金项目 |
| |
| 摘 要： | 云对红外辐射传输过程有十分重要的影响，在资料同化过程中考虑云的作用，不仅可以改进大气参数的同化效果，还可以利用红外资料调整部分云参数，减小云参数的初始误差。在GRAPES-3DVAR（Global and Regional Assimilation and Prediction Enhanced System，全球/区域同化预报系统）基础上，增加云水含量、云冰水含量和云量作为同化系统控制变量，针对晴空、部分有云和完全有云等环境对MODIS（Moderate Resolution Imaging Spectroradiometer，即中分辨成像光谱仪）的16个气象通道亮温进行了同化理想试验，结果表明当背景场模拟的亮温低于观测亮温时，分析场通过增温、减湿、减少云水含量、云冰水含量、云量可以达到升高模拟亮温的目的；反之可以降低模拟亮温；晴空环境下对温度、比湿的调整符合MODIS仪器的设计特点；有云环境下对云层以下的影响减弱。理想试验证实了在红外辐射资料同化过程中将云参数和大气参数同时作为同化系统控制变量，可以利用红外资料调整云参数和常规气象要素场，提高资料的利用率。
|
| 关 键 词： | 云参数 MODIS亮温资料 同化 |
MODIS BRIGHTNESS TEMPERATURE DATA ASSIMILATION UNDER CLOUDY CONDITIONS Ⅰ——Methods And Ideal Tests |
| |
| DING Wei-yu,WAN Qi-lin,ZHANG Chen-zhong,CHEN Zi-tong,HUANG Yan-yan.MODIS BRIGHTNESS TEMPERATURE DATA ASSIMILATION UNDER CLOUDY CONDITIONS Ⅰ——Methods And Ideal Tests[J].Journal of Tropical Meteorology,2009,25(6):649-659. |
| |
| Authors: | DING Wei-yu WAN Qi-lin ZHANG Chen-zhong CHEN Zi-tong HUANG Yan-yan |
| |
| Institution: | DING Wei-yu,WAN Qi-lin,ZHANG Chen-zhong,CHEN Zi-tong,HUANG Yan-yan (Guangzhou Institute of Tropical and Marine Meteorology,CMA,Guangzhou 510080,China) |
| |
| Abstract: | Clouds have important effects on the infrared radiances transmission in that the inclusion of cloud effects in data assimilation can not only improve the quality of the assimilated atmospheric parameters greatly, but also minimize the initial error of cloud parameters by adjusting part of the infrared radiances data. On the basis of the Grapes-3Dvar (Global and Regional Assimilation and Prediction Enhanced System), cloud liquid water, cloud ice water and cloud cover are added as the governing variables in the assimilation. Under the conditions of clear sky, partly cloudy cover and totally cloudy cover, the brightness temperature of 16 MODIS channels are assimilated respectively in ideal tests. The results show that when the simulated background brightness temperatures are lower than the observation, the analyzed field will increase the simulated brightness temperature by increasing its temperature and reducing its moisture, cloud liquid water, cloud ice water, and cloud cover. The simulated brightness temperature can be reduced if adjustment is made in the contrary direction. The adjustment of the temperature and specific humidity under the clear sky conditions conforms well to the design of MODIS channels, but it is weakened for levels under cloud layers. The ideal tests demonstrate that by simultaneously adding both cloud parameters and atmospheric parameters as governing variables during the assimilation of infrared radiances, both the cloud parameters and atmospheric parameters can be adjusted using the observed infrared radiances and conventional meteorological elements to make full use of the infrared observations. |
| |
| Keywords: | cloud parameters MODIS brightness temperature data assimilation |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《热带气象学报》浏览原始摘要信息 |
| 点击此处可从《热带气象学报》下载免费的PDF全文 |
|
