干旱区生态环境知识资源中心(Arid): 青藏高原土壤湿度触发午后对流降水模拟试验研究

Arid

	青藏高原土壤湿度触发午后对流降水模拟试验研究
其他题名	Simulation on Afternoon Convective Precipitation Triggered by Soil Moisture over the Qinghai-Tibetan Plateau
	栾澜; 孟宪红; 吕世华; 韩博; 李照国; 赵林; 李瑞青
来源期刊	高原气象
ISSN	1000-0534
出版年	2018
卷号	37 期号:4 页码:873-885
中文摘要	利用WRF模式设计敏感性试验并结合CTP-HI_(low)框架(对流触发潜能-低层大气湿度指数)研究了青藏高原土壤湿度变化对午后对流触发和抑制的影响。结果表明,WRF模式对青藏高原降水空间分布体现出了较好的模拟效果,且当土壤湿度减少时,对青藏高原西部降水的模拟有一定的改进。从整体上看,青藏高原地区夏季降水主要受大尺度环流控制,其比例占60%~90%,在高原中部、西南部地区以及东北部区域土壤湿度对降水的影响相对较大。模拟结果显示,当土壤湿度变干时,正反馈作用发生的情况多于负反馈,也就是说更多的情况下是变干的土壤抑制午后对流降水的发生,但也有一部分区域表现为变干的土壤触发午后对流降水的发生,即负反馈。高原西北部较干旱地区由于负反馈所引发的对流降水占总降水的比例较高原其他地区大,最大的影响可达总降水量的80%以上,其机理主要是由于变干的土壤影响地表通量的分配,增加了地表加热大气的感热通量,进一步使大气边界层快速发展,到达自由对流高度后,发生降水。通过对比控制试验和敏感性试验的CTP和H_(low)的值可以发现不同年份对应的CTP和HI_(low)的阈值存在一定的差异,表明土壤湿度是通过同时对地表能量和大气湿度状况协同影响,从而对午后对流触发产生作用。
英文摘要	This study designed sensitive experiments using WRF model and used CTP-HI_(low) framework to investigate the influences of soil moisture change on triggering and inhibiting the afternoon convective precipitation over the Qinghai-Tibetan Plateau. The results show that WRF model can reproduce the spatial distribution of the precipitation over the Qinghai-Tibetan Plateau. In addition, there are some improvements of the precipitation simulation over the west part of the Qinghai-Tibetan Plateau when soil moisture decreases. In general, the statement of large scale atmospheric circulation dominates the occurrence of the afternoon convective precipitation process,especially in the middle, southwestern and northeastern part of the Qinghai-Tibetan Plateau. The large scale atmospheric circulation caused the triggering and inhibiting afternoon convective precipitation events account for about 60% ~90% of the total number of the triggered and inhibited precipitation events. According to the results of the simulation, when soil moisture decreases, there are more positive feedback cases than negative feedback cases between soil moisture and afternoon convective precipitation which means the decreasing of the soil moisture inhibits the occurrence of afternoon convective precipitation in most cases. However, relative smaller proportion of the cases is the decreasing soil moisture that triggers the afternoon convective precipitation which is the negative feedback. The amount of convective precipitation triggered by the negative feedback process accounts for larger proportion in the northwest part which is the arid part of the Qinghai-Tibetan Plateau. It has the center value up to 80% or more. The mechanism of negative feedback is that the decreasing soil moisture increases the surface sensible heat flux which influences the distribution of sensitive heat flux over the Qinghai-Tibetan Plateau. The increased sensible heat flux contributes to the development of the boundary layer which makes the air parcel easier to reach the level of free convection and the occurrence of afternoon convective precipitation. By comparing the values of CTP and HI_(low) between control and sensitive experiments in different years, to some extent, there are differences between these two years. It means that soil moisture can influence occurrence of afternoon convective precipitation through its influences both on the surface energy and the atmosphere humidity.
中文关键词	青藏高原 ; 土壤湿度 ; 对流降水 ; 数值模拟
英文关键词	Qinghai-Tibetan Plateau soil moisture convective precipitation numerical simulation
类型	Article
语种	中文
收录类别	CSCD
WOS类目	Meteorology & Atmospheric Sciences
CSCD记录号	CSCD:6312181
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/378936
作者单位	栾澜, 中国科学院西北生态环境资源研究院;;中国科学院大学, 中国科学院寒旱区陆面过程与气候变化重点实验室;;, 兰州;;, 甘肃;;北京 730000;;l00049, 中国.; 孟宪红, 中国科学院西北生态环境资源研究院, 中国科学院寒旱区陆面过程与气候变化重点实验室, 兰州, 甘肃 730000, 中国.; 韩博, 中国科学院西北生态环境资源研究院, 中国科学院寒旱区陆面过程与气候变化重点实验室, 兰州, 甘肃 730000, 中国.; 李照国, 中国科学院西北生态环境资源研究院, 中国科学院寒旱区陆面过程与气候变化重点实验室, 兰州, 甘肃 730000, 中国.; 赵林, 中国科学院西北生态环境资源研究院, 中国科学院寒旱区陆面过程与气候变化重点实验室, 兰州, 甘肃 730000, 中国.; 吕世华, 成都信息工程大学大气科学学院;;南京信息工程大学, 高原大气与环境四川省重点实验室;;气象灾害预报预警与评估协同创新中心, 成都;;南京, 四川;;江苏 610225;;210044, 中国.; 李瑞青, 内蒙古气象台, 呼和浩特, 内蒙古 010020, 中国.
推荐引用方式 GB/T 7714	栾澜,孟宪红,吕世华,等. 青藏高原土壤湿度触发午后对流降水模拟试验研究[J],2018,37(4):873-885.
APA	栾澜.,孟宪红.,吕世华.,韩博.,李照国.,...&李瑞青.(2018).青藏高原土壤湿度触发午后对流降水模拟试验研究.高原气象,37(4),873-885.
MLA	栾澜,et al."青藏高原土壤湿度触发午后对流降水模拟试验研究".高原气象 37.4(2018):873-885.