巴山西段米仓山北坡近地面气温垂直变化特征  

Vertical Variation of Near Surface Temperature on the Northern Slope of Micang Mountain in the Western Bashan Mountain

作　　者：戴进[1,3] 赵奎锋 董自鹏[1,3] 彭艳 徐小红[1,3] 陈闯 DAI Jin;ZHOU Kuifeng;DONG Zipeng;PENG Yan;XU Xiaohong;CHEN Chuang(Meteorological Institute of Shaanxi Province,Xi’an 710014,Shaanxi,China;Shaanxi Meteorological Observatory,Xi’an 710016,Shaanxi,China;Key Laboratory of Eco-Environment and Meteorology for The Qinling Mountains and Loess Plateau,Shaanxi Meteorological Bureau,Xi’an 710014,Shaanxi,China)

机构地区：[1]陕西省气象科学研究所,陕西西安710014 [2]陕西省气象台,陕西西安710016 [3]秦岭和黄土高原生态环境气象重点实验室,陕西西安710014

出　　处：《高原气象》2023年第4期1055-1068,共14页Plateau Meteorology

基　　金：国家自然科学基金项目(41905016);陕西重点产业创新链(群)项目(2020ZDLSF06-02)。

摘　　要：巴山是中国中亚热带气候和北亚热带气候的分界线,深入了解区域内复杂地形下近地面气温的垂直变化特征,可为气候变化研究、生态监测、生态环境保护等提供依据及基础数据。利用2013-2019年巴山西段米仓山北坡高差超过1400 m的4个区域自动气象站和周围3个气象站的近地面实测温度,结合2017-2019年汉中探空资料,分析了米仓山北坡近地面气温的垂直变化特征,比较了近地面气温和环境大气气温递减率(γ)的差异,探讨了其垂直气候带。结果表明:(1)近地面气温随海拔升高而下降,在7月和1月分别达到最高和最低。年均γ为0.624±0.136℃·(100m)^(-1),与自由大气γ比较接近。月均γ在12月最小,随月份逐步增加,8月达最大后再减小。γ季节变化明显,暖季γ值较高,冷季较低,春夏秋冬季均γ分别为0.647±0.099℃·(100m)^(-1)、0.732±0.103℃·(100m)^(-1)、0.605±0.113℃·(100m)^(-1)和0.508±0.120℃·(100m)^(-1)。日最高/最低气温与日均气温的月季变化类似,年均γ分别为0.646±0.185℃·(100m)^(-1)和0.606℃±0.166℃·(100m)^(-1);各高度上年均日较差在7~10℃之间波动,与高度不存在明显的线性关系;年较差随高度增加呈线性下降。(2)近年来,区域内γ下降趋势可能已经发生了改变,很大程度上归因于高海拔地区与低海拔地区辐射差异快速缩小,以及气溶胶与前期相反的垂直变化趋势。(3)随高度增加,积温线性下降,递减率约213℃·(100m)^(-1);日平均气温≥0、5和10℃温度阈值的初日推后,终日提早,间隔日数缩短,每升高100 m,其积温持续天数分别减少3.4天、6.1天和7.0天。(4)在0.5~1.0 km、1.0~2.5 km、2.5~4.5 km和4.5 km以上,环境大气温度随高度变化的层次性明晰,反映了青藏高原大地形、秦岭地形、米仓山地形和下垫面对气温垂直变化的综合影响。4个高度区间内γ的差异较大,逆温尤其是冬季边界层上部和对流层中层逆温对Bashan Mountain is the division line between middle subtropical climate and northern subtropical climate in China.The further analysis and understanding of the vertical variation of near surface temperature under such complex terrain can provide foundation and basic data for climate change,ecological monitoring and ecological environment protection in this region.Based on the measured data of daily near surface temperature on the northern slope of Micang Mountain during 2013-2019 from four automatic stations and 3 surrounding meteorological stations,which covers an elevation difference more than 1400 m,combined the sounding data at Hanzhong sounding station from 2017 to 2019,the lapse rates(γ)of near surface temperature and ambient atmospheric temperature were compared,and the vertical variation of near surface temperature on the north slope of Micang Mountain was analyzed,also its vertical climate zone is discussed.The results show that:(1)The near surface temperature decreases with the increasing altitude,its monthly average temperature reaches the highest and lowest in mid-July and January respectively.The average annual γ is 0.624±0.136℃·(100m)^(-1) during the observation period,close to that of free atmosphere.The average monthlyγis the smallest in December,increases gradually to August and then decreases,representing a distinct seasonal trend that steeper lapse rates occurred during warmer months,while shallower lapse rates occurred during colder months.The seasonal γ are 0.647±0.099,0.732±0.103,0.605±0.113 and 0.508±0.120℃·(100m)^(-1) in the spring,summer,autumn and winter,respectively.The variation of maximum/minimum temperature is similar with that of average temperature,with an annual γ 0.646±0.185 and 0.606±0.166℃·(100m)^(-1) respectively.The average annual daily range has no obvious difference in each height,fluctuating between 7℃ and 10℃,and has no obvious linear relationship with the height.The annual range decreases linearly with the increasing height.(2)The decreasing tren

关 键 词：垂直变化 气温递减率 垂直气候带 秦巴山地 米仓山 

分 类 号：P461.3[天文地球—大气科学及气象学]