干旱区生态环境知识资源中心(Arid): 黄土高原自然植被下垫面陆面过程参数研究

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	黄土高原自然植被下垫面陆面过程参数研究
其他题名	A study of the parameterization of land-surface processes over the natural vegetation surface of Loess Plateau
	李宏宇 1; 张强2 ; 史晋森 3; 赵建华 4; 王胜 4
来源期刊	气象学报
ISSN	0577-6619
出版年	2012
卷号	70 期号:5 页码:1137-1148
中文摘要	利用兰州大学半干旱气候与环境观测站的观测资料,分析了黄土高原自然植被下垫面陆面过程相关物理参数。研究了总体输送系数的不同季节平均日变化和频率分布特征,考察了地表粗糙度的变化趋势以及降水的影响。降水正常年份的总体粗糙度为0.009m,偏干年份总体粗糙度为0.006m,月平均粗糙度变化与正常年份相比较为平缓,降水通过增加植被覆盖和生长高度,使地表粗糙度增大。对总体输送系数与粗糙度以及总体理查森数的关系分别进行了讨论,在中性层结下黄土高原地区动力输送作用占主导地位,发现动量总体输送系数和奈曼流动沙丘下垫面很接近,而感热输送系数与戈壁下垫面接近。分析了反照率和太阳高度角以及土壤湿度的关系,并拟合得到以这两个物理量为因子的参数化公式。总体上,黄土高原自然植被下垫面的反照率比敦煌荒漠小,而大于长白山松林下垫面,这与3个地区植被覆盖和土壤质地的不同有关。通过对参数化公式模拟效果的检验,发现低太阳高度角下的反照率对土壤湿度和太阳高度角以外的其他因素敏感,而对应高太阳高度角的反照率受土壤湿度和太阳高度角的控制较强。最后,计算了土壤热传导率和热扩散率等土壤热力参数,相同湿度的热传导率比敦煌荒漠要大,并拟合得到热传导率以土壤湿度为自变量的参数化公式。
英文摘要	Based on the data observed at the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL),the physical parameters related to land-surface processes over the natural vegetation surface of Loess Plateau are calculated.The paper studied averaged diurnal variations and the frequency distributions of the bulk transfer coefficients in the different seasons,and analyzed the trend of the surface roughness as well as effects of precipitation on the roughness.Monthly averages of the roughness in a normal year of precipitation have more changes compared with those in a dryer year since precipitation increasing tends to increase the roughness.The roughness in a normal year is 910-3 m,while the roughness in a dryer year decreases to 610-3 m.The rainfall raises the roughness by increasing the vegetation cover and height.Relationships among the bulk transfer coefficients and the two factors including surface roughness and the Richardson number are discussed. The role of dynamical transfer in land-atmosphere energy exchange over the Loess Plateau is dominant.Additionally,the neutral bulk transfer coefficient for momentum is close to that over the movable dune at Naiman in Inner Mongolia and the neutral bulk transfer coefficient for sensible heat is close to that over Gobi.We also analyzed effects of solar elevation angle and soil moisture on surface albedo and preliminarily a multiple factorial parameterization formula of surface albedo is suggested.Generally, the albedo over the Loess Plateau is smaller than that over the desert of Dunhuang and larger than that over pine forests in Changbai Mountain.The various vegetation covers and soil types in the three regions lead to differences of albedo.By testing the simulation results of the albedo formula,it is found that the albedo with low solar elevation angles is sensitive to the other factors except soil moisture and solar elevation angle,while soil moisture and solar elevation angle affect the albedo with high solar elevation angles significantly. Whats more,the soil thermal parameters including soil thermal conductivity and thermal diffusion are calculated as well.In the same soil moisture,the soil thermal conductivity is larger than that in desert of Dunhuang.In the end,aparameterization formula of soil thermal conductivity is gotten by fitting the thermal conductivity and the soil moisture.
中文关键词	黄土高原 ; 粗糙度 ; 总体输送系数 ; 反照率 ; 土壤热传导率 ; 土壤热扩散率
英文关键词	Loess Plateau Surface roughness Bulk transfer coefficient Surface albedo Soil thermal conductivity Soil thermal diffusion
语种	中文
国家	中国
收录类别	CSCD
WOS类目	METEOROLOGY ATMOSPHERIC SCIENCES
WOS研究方向	Meteorology & Atmospheric Sciences
CSCD记录号	CSCD:4709871
来源机构	兰州大学 ; 中国气象局兰州干旱气象研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/228377
作者单位	1.南京大学气候与全球变化研究院,大气科学学院, 甘肃省干旱气候变化与减灾重点实验室;;中国气象局干旱气候变化与减灾重点开放实验室, 南京, 江苏 210093, 中国; 2.中国气象局兰州干旱气象研究所, 甘肃省干旱气候变化与减灾重点实验室;;中国气象局干旱气候变化与减灾重点开放实验室;;半干旱气候变化教育部重点实验室, 兰州, 甘肃 730020, 中国; 3.兰州大学大气科学学院, 半干旱气候变化教育部重点实验室, 兰州, 甘肃 730000, 中国; 4.中国气象局兰州干旱气象研究所, 甘肃省干旱气候变化与减灾重点实验室;;中国气象局干旱气候变化与减灾重点开放实验室, 兰州, 甘肃 730020, 中国
推荐引用方式 GB/T 7714	李宏宇,张强,史晋森,等. 黄土高原自然植被下垫面陆面过程参数研究[J]. 兰州大学, 中国气象局兰州干旱气象研究所,2012,70(5):1137-1148.
APA	李宏宇,张强,史晋森,赵建华,&王胜.(2012).黄土高原自然植被下垫面陆面过程参数研究.气象学报,70(5),1137-1148.
MLA	李宏宇,et al."黄土高原自然植被下垫面陆面过程参数研究".气象学报 70.5(2012):1137-1148.