戈壁地区夏季碳和水热循环及其湍流特征  

Characteristics of carbon dioxide,thermo-hydrological fluxes and atmospheric turbulence structure over Gobi Desert

作　　者：赵子龙[1] 张宏升[1] 康凌[2] 

机构地区：[1]北京大学物理学院大气与海洋科学系,气候与海气实验室,北京100871 [2]北京大学环境科学与工程学院,北京100871

出　　处：《地球物理学报》2013年第8期2574-2582,共9页Chinese Journal of Geophysics

基　　金：国家自然科学基金(41075005);国家重点基础研究发展规划项目(2010CB428501);高等学校博士学科点专项科研基金资助课题(20110001130010);财政部/科技部公益性行业(气象)科研专项(GYHY201006014)资助

摘　　要：本文利用2006年夏季大气边界层观测资料,采用涡动相关法分析了我国西北地区戈壁下垫面碳收支及水热循环的规律和特征,并分析了大气湍流特征.结果表明:夏季白天的CO2湍流通量呈逆输送特征,即CO2白天向下输送,夜间向上输送,平均数值为-0.199mg·m-2·s-1,整体上表现为碳汇;戈壁地区湿度小,其数值受水平来流的影响较大,日变化特征不明显;温度的归一化标准差与稳定度参数的关系满足Monin-Obukhov Similarity(MOS)理论;温度和CO2的能谱相似;互谱uc与uθ,wc与wθ相似;水汽和CO2的输送主要受水平方向湍流的影响.Based on the turbulence data obtained from an atmospheric boundary layer station located in Gobi Desert in northwest China during the summer of 2006, the carbon dioxide fluxes, latent heat fluxes and sensible heat fluxes were investigated. The results showed that the carbon dioxide flux was transferred down to land surface in daytime but conversely at night, and the mean value of carbon dioxide flux was -0. 199 mg·m^-2·s^-1, which indicated that the Gobi Desert was a carbon sink in summer. Since the value of the moisture content of the surface layer over the Gobi Desert was small, the specific humidity is almost passively controlled by horizontal moisture fluxes and its diurnal variation was unobvious. On the other hand, the statistical characteristic of the turbulent transport of temperature was in accordance with Monin-Obukhov Similarity theory. The normalized spectra of temperature were similar with that of the CO2 concentration （c）. The normalized cospectra of u-wind component （u） and carbon dioxide （c） were similar with that of u and the potential temperature （θ）. The normalized eospectra of theverlical wind component （w） and carbon dioxide （c） were similar with that of w and θ. The transporl of humidity and CO2 depended on horizontal fluxes.

关 键 词：湍流输送 谱特征 碳通量 戈壁地区 

分 类 号：P404[天文地球—大气科学及气象学]