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Validation of the Atmospheric Infrared Sounder Retrieval Products over China and Their Application in Numerical Mode 
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下载免费PDF全文 The atmospheric infrared sounder (AIRS) instrument onboard Aqua Satellite is a high spectral resolution infrared sounder. In recent years, AIRS has gradually become the primary method of atmospheric vertical observations. To examine the validation of AIRS retrieval products (V3.0) over China, the AIRS surface air temperature retrievals were compared with the ground observations obtained from 540 meteorological stations in July 2004 and January 2005, respectively. The sources of errors were considerably discussed. Based on the error analysis, the AIRS retrieved surface air temperature products were systemically corrected. Moreover, the AIRS temperature and humidity profile retrievals were compared with T213 numerical forecasting products. Because T213 forecasting products are not the actual atmospheric states,to further verify the validation, the AIRS temperature and humidity profile products were assimilated into the MM5 model through the analysis nudging. In this paper, the case on February 14, 2005 in North China was simulated in detail. Then, we investigated the effects of AIRS retrievals on snowfall, humidity field,vertical velocity field, divergence field, and cloud microphysical processes. The major results are: (1) the errors of AIRS retrieved surface air temperature products are largely systematic deviations, for which the influences of terrain altitude and surface types are the major reasons; (2) the differences between the AIRS atmospheric profile retrievals and T213 numerical prediction products in temperature are generally less than
2 K, the differences in relative humidity are generally less than 25%; and (3) the AIRS temperature and humidity retrieval products can adjust the model initial field, and thus can improve the capacity of snowfall simulation to some extent. 相似文献
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利用平矩阵风廓线雷达于2007年7月17日至9月28日对上海世博园规划区上空的风垂直分布进行了观测.通过分析该地上空三维风场的日变化,发现夜间以偏西气流为主,白天风速较小,以偏东气流为主,表明该地区以海陆风为主导的环流特征是这一地区的局地环流日变化的基本特征.逐日变化分析表明,在8月2日以前主要以偏西北气流为主,之后基本是以东南气流为主,并且垂直运动特征以上升气流为主,强烈的垂直运动与偏西气流相关密切,同时偏北气流往往带来较强的上升运动.日夜平均廓线分析表明,夜间风速较大,并且夜间风速的垂直变化与白天相比也有很大不同,白天270 m以下风速随高度基本不变,而夜间从近地面向上风速随高度逐渐增大,低层<90 m的范围内白天风速大于夜间风速.城市冠层以上风向的日夜变化不明显,多为偏北气流控制.城郊风廓线的对比表明受城市下垫面粗糙度的影响,城市风速明显比郊区减小.城市和郊区的水平风速变化在城市冠层以上比较接近,相关系数达到了87%. 相似文献
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CLIMATIC CHARACTERISTICS OF TYPHOON PRECIPITATION OVER CHINA 总被引：2，自引：0，他引：2
The spatio-temporal characteristics of typhoon precipitation over China are analyzed in this
study. The results show that typhoon precipitation covers most of central-eastern China. Typhoon
precipitation gradually decreases from the southeastern coastal regions to the northwestern mainland. The
maximum annual typhoon precipitation exceeds 700 mm in central-eastern Taiwan and part of Hainan,
while the minimum annual typhoon precipitation occurs in parts of Inner Mongolia, Shanxi, Shaanxi and
Sichuan, with values less than 10 mm. Generally, typhoons produce precipitation over China during April
– December with a peak in August. The annual typhoon precipitation time series for observation stations
are examined for long-term trends. The results show that decreasing trends exist in most of the stations
from 1957 to 2004 and are statistically significant in parts of Taiwan, Hainan, coastal Southeast China and
southern Northeast China. The anomaly of typhoon precipitation mainly results from that of the general
circulation over Asia and the Walker Cell circulation over the equatorial central and eastern Pacific.
Typhoon torrential rain is one of the extreme rainfall events in the southeastern coastal regions and parts of
central mainland. In these regions, torrential rains are mostly caused by typhoons. 相似文献
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山西中条山地区是我国重要的铜成矿带,发育铜矿峪斑岩型铜矿和“胡(家峪) 篦(子沟)”型铜矿。本文对铜矿峪铜矿的黄铁矿和黄铜矿、胡家峪铜矿的黄铁矿开展了流体包裹体中的He、Ar同位素组成研究。铜矿峪黄铁矿、黄铜矿流体包裹体中的 4 He含量为46. 23×10 -8 ~1195. 75×10 -8 cm 3 STP/g, 3 He/ 4 He比值为0. 01~0. 06Ra, 40 Ar含量为1. 69×10 -8 ~74. 11×10 -8 cm 3 STP/g; 40 Ar/ 36 Ar为407~2327. 8。胡家峪黄铁矿流体包裹体中 4 He含量为314. 06×10 -8 ~3815. 87×10 -8 cm 3 STP/g; 3 He/ 4 He为0. 003~0. 014Ra , 40 Ar含量为25. 62×10 -8 ~761. 51×10 -8 cm 3 STP/g; 40 Ar/ 36 Ar 值为936. 1~4108. 6。中条山地区铜矿床 3 He/ 4 He值明显指示壳源He特征,铜矿峪、胡家峪样品中幔源He的含量介于0~0. 56%之间,幔源He对成矿的贡献可忽略不计。在成矿流体的 40 Ar/ 36 Ar- 3 He/ 4 He和 40 Ar*/ 4 He 3 He/ 4 He关系图解中所有样品均投点于壳源流体区域,显示Ar为地壳来源。因此,中条山地区大规模成矿作用以壳源流体成矿为主,并未发现幔源流体参与成矿的踪迹。 相似文献
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运城盐湖滩田生产工艺特殊,一年之中,春季淡水溶解盐类矿床,经过夏季蒸发提浓、配兑,冬季母液分离得到产品。盐湖地处运城盆地,春季干旱少雨,淡水资源不足,严重制约滩田生产。城市污水进行深度处理达二级排放标准的再生水,是解决水资源短缺的有效途径。从政策、技术、经济等方面进行分析,再生水可作为滩田生产用水,既保证了充足的水源供应,又大幅度降低了生产成本,可收到良好的社会效益和经济效益。 相似文献
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