Clear and cloudy sky investigations using Raman lidar and airborne interferometric measures from the European AQUA Thermodynamic Experiment
Clear and cloudy sky investigations using Raman lidar and airborne interferometric measures from the European AQUA Thermodynamic Experiment
复制标题
使用欧洲 AQUA 热力学实验的拉曼激光雷达和机载干涉测量方法进行晴空和多云天空调查
DOI：
10.1016/j.atmosres.2010.03.020
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发表时间：
2010
影响因子：
5.5
通讯作者：
R. Rolando
中科院分区：
文献类型：
--
作者：
Maestri Tiziano;D. Paolo;Summa Donato;R. Rolando
在2004年全面的EAQUATE（欧洲AQUA热力学实验）意大利活动期间测量了地面、空中和卫星数据的数据集。我们使用地面和机载数据来评估拉曼激光雷达温度和湿度廓线与NAST-I（国家极轨运行环境卫星系统机载探测器试验台干涉仪）光谱辐射测量在清晰条件下的一致性，以及由拉曼激光雷达测量的总云光学厚度与从NAST-I测量中检索的相同数量的一致性。激光雷达测量的温度和湿度分布可以解决混合比的短时间变化，由于其高的时间分辨率。使用激光雷达获得的轮廓进行的晴空亮温模拟，与考虑25 cm − 1以上平均值和7 km以下层发射的数据相比，差异在1 K以内。高光谱分辨率模拟与NAST-I测量结果一致，在整个ν 2水汽带中的平均百分比差异小于0.5%。在多云条件下的模拟是基于获得的晶体性质，假设或者是适当的混合物的晶体习惯（第一次测试对高光谱分辨率测量）或原始的固体柱。激光雷达派生的云的底部和顶部高度和激光雷达温度和湿度廓线的开发，第一次，作为输入，在最近开发的红外云属性检索程序。从800到980 cm − 1 NAST-I辐射率反演的云总光学厚度，当转换为短波波长时，其值在0.05-2.2之间，与激光雷达测量值在实验误差范围内一致。一个更接近的协议是获得与习惯的混合。模拟高分辨率的亮度温度检索云参数（光学深度和有效尺寸）的基础上进行比较，在所有的大气窗口覆盖的NAST-I传感器的测量值。在800- 980 cm − 1的光谱区间内，对于混合习性而言，一般来说，两者的一致性更好，但是在2000-2150和2400- 2600 cm − 1的光谱区间内，实心柱产生的残差较小。与表面性质（即表皮温度）相关的非均匀性被认为是云特性红外反演中误差的主要来源，并影响正演模拟和NAST-I数据在所有不用于反演问题的红外窗口波段之间的比较。
A dataset of ground, airborne and satellite data was measured during the comprehensive 2004 EAQUATE (European AQUA Thermodynamic Experiment) Italian campaign. We have used ground based and airborne data to evaluate the consistency of Raman lidar temperature and humidity profiles with NAST-I (The National Polar-orbiting Operational Environmental Satellite System Airborne Sounder Testbed-Interferometer) spectral radiance measurements in clear conditions, and the consistency of total cloud optical depth measured by the Raman lidar with the same quantity retrieved from NAST-I measurements. Lidar measurement of temperature and humidity profiles can resolve short time changes in mixing ratio due to its high time resolution. Brightness temperature simulations of clear sky, performed using lidar-derived profiles, are within 1K difference with respect to data when averages over 25cm−1and emission from layers below 7km are considered. High spectral resolution simulations agree with NAST-I measurements with a mean percentage difference less than 0.5% in the whole ν2water vapour band. The simulations in cloudy conditions are based on crystal properties obtained assuming either an appropriate mixture of crystal habits (that for the first time is tested against high spectral resolution measurements) or pristine solid columns. Lidar-derived cloud base and top altitudes and lidar temperature and humidity profiles are exploited, for the first time, as inputs in a recently developed infrared cloud properties retrieval procedure. Total cloud optical depths, retrieved from 800 to 980cm−1NAST-I radiances, have values that, when converted to short-wave wavelengths, are in the range 0.05–2.2 and agree with lidar measurements to within experimental errors. A closer agreement is obtained with the mixture of habits. Simulated high resolution brightness temperatures based on retrieved cloud parameters (optical depths and effective dimensions) are compared with measured values in all the atmospheric windows covered by the NAST-I sensor. The agreement obtained in the 800–980cm−1interval is generally better for the mixture of habits, but solid columns produce smaller residuals in the 2000–2150 and 2400–2600cm−1spectral intervals. Uncertainties related to the surface properties (i.e. skin temperature) are recognized to be the main sources of error in the infrared retrieval of cloud properties and affect the comparison between forward simulations and NAST-I data in all the infrared window bands not used for the inverse problem.