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利用NCEP/NCAR再分析资料、GPCP降水资料以及我国160个台站的降水资料, 研究了青藏高原臭氧低值中心偏强年和偏弱年的气候差异。结果表明，5～7月平均的青藏高原臭氧总量变化与我国当年夏季、冬季以及第二年春季的气温和降水等有明显的相关关系:在臭氧低值中心偏强年夏季, 中国绝大部分地区地面气温比多年平均偏高, 长江以南地区降水偏多, 长江以北大部分地区降水偏少, 尤其是长江中下游和黄河中下游之间的地面降水偏少特别明显。在臭氧低值中心偏强年冬季和次年春季, 中国大部分地区冬季风比多年平均弱, 使得绝大部分地区地面气温偏高。臭氧低值中心偏弱年的情况基本上与偏强年相反。因此, 青藏高原上空臭氧低值中心的变化在气候预测中是一个值得重视的因子。 相似文献
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大尺度山地上空的臭氧低值及地面加热 总被引：11，自引：0，他引：11
首次利用Ｎｉｍｂｕｓ－７卫星上搭载的臭氧观测光谱仪（ＴＯＭＳ）资料,分析研究了大尺度山地（青藏高原、洛基山脉和安第斯山脉）上空臭氧总量的分布和季节变化规律,指出了大尺度山地对大气臭氧的减少作用。从全球大气臭氧总量分布和纬向偏差分布可以看出：在上述３个大尺度山地上空均存在着明显的臭氧低值扰动,该扰动区夏季强于冬季。在这３个区域中,青藏高原上空的臭氧低值扰动为最强。分析同时指出：上述大尺度山地上空臭氧季节变化的极小值在秋季,极大值在春季。但上述地区臭氧总量与同纬度其它地区臭氧总量的偏差在春季或初夏达到极小值。为分析这种大尺度山地对臭氧减少作用的原因,本文分析了青藏高原地面热源与臭氧总量的关系,指出：大尺度山地表面对大气的加热与该地区臭氧减少之间存在着良好的反相关;在地面对大气的感热加热、潜热加热和有效长波辐射加热中,以感热加热与臭氧减少的关系为最好。 相似文献
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利用MLS卫星资料和ERA-Interim再分析资料,比较了青藏高原和北美夏季臭氧谷的垂直结构和形成机制。结果如下:青藏高原夏季臭氧谷在垂直方向上存在两个低值中心,一个中心位于对流层顶附近,强度约为-15 DU,形成原因主要为水平幅散,另一个中心位于上平流层,强度约为-1 DU,形成原因可能为光化学反应参与的氯自由基的催化损耗。北美夏季臭氧谷仅存在一个低值中心,位于对流层顶附近,该中心强度约为-5 DU,其形成的主要原因是水平辐散。 相似文献
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Impacts of the atmospheric apparent heat source over the Tibetan Plateau on summertime ozone vertical distributions over Lhasa 
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下载免费PDF全文 Wenjun Liang Zhen Yang Jiali Luo Hongying Tian Zhixuan Bai Dan Li Qian Li Jinqiang Zhang Haoyue Wang Bian Ba Yang Yang 《大气和海洋科学快报》2021,14(3):66-71
青藏高原(TP)是一个对气候变化敏感的地区,其上空的臭氧分布影响着青藏高原及其周边地区的大气环境,北半球夏季青藏高原上空臭氧柱总量相对较低的现象,及其时空变化受到广泛关注.本研究利用北半球夏季5年的拉萨上空臭氧的气球测量数据,研究高原上空大气视热源(Q1)对臭氧垂直分布的影响并探讨了该过程的机制.结果表明,当TP上空对流层整体的Q1相对较高时,拉萨上空对流层臭氧浓度下降.大气更强的上升运动伴随着TP主体区域上空的Q1的增大.因此,当夏季Q1较高时,由于近地表低浓度臭氧空气向上输送,拉萨上空的对流层臭氧浓度下降. 相似文献
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《高原气象》2017,(5)
使用2005—2015年夏季Aura卫星微波临边探测器(MLS)逐日臭氧观测资料,讨论了夏季青藏高原臭氧低值区的三维分布。研究发现,青藏高原臭氧不仅在对流层顶附近存在着臭氧低值区,而且在平流层上层(20~1 hPa)也存在显著的低值区。高原区上空50%以上的臭氧存在于21.5~1.2 hPa的范围内,因此平流层上层高原臭氧低值对高原臭氧谷来说也很重要。使用合成分析法对MLS夏季北半球昼夜臭氧进行研究,结果表明该低值区仅存在于白天。根据高原区平流层上层臭氧模拟数据的集合经验模态分解,得到IMF4的平均频率为0.09,平均周期为11.1年,正好对应太阳活动最强的周期。说明太阳辐射是影响高原平流层上层臭氧低值中心的一个因素。 相似文献
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汤洁 《中国气象科学研究院年报》1998,(1)
本项目由国家自然科学基金委员会面上项目《青藏高原大气臭氧和气溶胶的观测研究》和中国气象科学研究院大气化学开放实验室经费共同支持项目负责人为中国科学院大气物理研究所石广玉研究员和中国气象科学研究院汤洁副研究员。目的通过对青藏高原地区上空大气臭氧和相关前体物、气溶胶进行综合观测,研究青藏高原地区上空夏季大气臭氧低谷形成的过程、物理化学成因和机制。背景”八五一期间国家自然科学基金的重大项目”中国地区大气臭氧变化及其对气候环境的影响”的研究结果揭示了青藏高原地区上空夏季6－9月间存在着大气臭氧总量的异常低… 相似文献
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青藏高原瓦里关地区大气臭氧柱总量及UV—B观测结果的特征分析 总被引：2，自引：0，他引：2
利用Brewer臭氧分光光谱仪对青藏高原东北部瓦里关地区的大气臭氧柱总量及太阳紫外B生物有效辐射剂量进行了连续的观测。通过对1996-1996年的资料分析表明：该地区的臭氧柱总量具有明显的年季变化特征，并存在着减少的趋势，与TOMS卫星的观测结果相一致；臭氧垂直廓线的Umkehr反演得出这一地区的臭氧数密度最大值出现在20-30km处，冬春季的高度低于夏季；太阳紫外B生物有效辐射剂量夏季最高可达0．4W／m^2。 相似文献
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中国地区对流层臭氧变化和分布的数值研究 总被引：15，自引：1，他引：14
利用三维中尺度非静力模式ＭＭ５和化学模式,对１９９４年８月１６～１８日,１９９５年１月７～９日冬夏两个不同时期中国大陆大气对流层臭氧及其前体物质的分布进行了数值模拟。同时深入地分析了青藏高原地区夏季对流层臭氧的分布。模拟结果地面臭氧和ＮＯｘ的分布与观测结果基本一致,人类活动和光化过程是决定地面臭氧和ＮＯｘ的主要因子。对流层臭氧浓度的分布与气流的辐合辐散存在较好的对应关系,辐合区臭氧浓度较高,辐散区臭氧浓度较低。夏季,青藏高原中低空存在很强的辐合气流,使周边臭氧向高原辐合;而高原高空,受南亚高压控制存在很强的反气旋环流,臭氧由高原向周边辐散。冬季,受西风气流控制,臭氧分布表征大尺度特征。西风急流区臭氧浓度偏低,而急流两侧臭氧浓度偏高。 相似文献
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1998年青藏高原臭氧低值中心异常及其背景环流场的分析 总被引：4，自引：1，他引：3
采用TOMS和SAGE II臭氧卫星观测资料,对1998年青藏高原臭氧低值中心异常变化的过程和垂直结构进行了分析。为了探讨1998年这个低值中心出现异常的原因,利用NCEP/NCAR再分析资料,通过1998年高原附近上空位势场和位温的变化,分析了1998年臭氧低值中心异常期间高原上空对流层上层到平流层下层的流场和垂直运动的变化特征。结果表明,1998年11月,青藏高原上空对流顶比正常年份高,无论是对流层上层还是平流层下层,上升运动都比正常年份强。同时高原上空南亚高压也比正常年份强,于是使得1998年高原上空的强臭氧低值中心一直维持到11月。 相似文献
11.
This paper reviewed the main results with respect to the discovery of low center of total column ozone (TCO) over the Tibetan Plateau (TP) in summer, and its formation mechanism. Some important advances are summarized as follows: The fact is discovered that there is a TCO low center over the TP in summer, and the features of the background circulation over the TP are analyzed; it is confirmed that the TP is a pathway of mass exchange between the troposphere and stratosphere, and it influences the TCO low center over the TP in summer; models reproduce the TCO low center over the TP in summer, and the formation mechanism is explored; in addition, the analyses and diagnoses of the observation data indicate that not only there is the TCO low center over the TP in summer, but also TCO decrease trend over the TP is one of the strong centers of TCO decrease trend in the same latitude; finally, the model predicts the future TCO change over the TP. 相似文献
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青藏高原东北侧臭氧垂直分布与平流层-对流层物质交换 总被引：3，自引：0，他引：3
利用臭氧和温度探空廓线,结合NCEP/NCAR资料、TOMS臭氧总量卫星观测资料和NOAAHYSPLIT后向轨迹模式资料,通过个例分析探讨了影响青藏高原(下称高原)附近臭氧垂直分布的因子和过程。结果表明,动力过程是影响高原上空臭氧垂直分布的主要因子,特别是中高纬度高臭氧浓度的空气向南入侵会导致高原上空臭氧浓度的升高,影响高原上空臭氧低谷的范围大小和形态;尽管大气化学过程对高原上空的平流层下层臭氧垂直分布的影响并不显著,但是高原上空的平流层臭氧变化与温度变化具有较好的一致性。同时还发现,对流层上层的强反气旋系统,特别是中高纬度阻塞高压的边缘有明显的平流层空气向对流层入侵,从而导致对流层内臭氧浓度的增加。 相似文献
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该文对半个世纪以来, 我国气象工作者在青藏高原研究, 特别是1979年和1998年两次大规模青藏高原大气科学试验科学成果进行了全面回顾, 给出近年来青藏高原研究许多有重要价值的研究成果, 可概要地归纳为以下几个方面:两次青藏高原大气科学试验在青藏高原边界层研究、对流特征研究方面取得新进展, 发现许多新的观测事实。证明青藏高原也可能是低频振荡源地。试验发现青藏高原摩擦层风的Ekman螺线及热力混合层特征, 发现青藏高原上对流边界层高度可达2200 m, 湍流边界层高度比平原地区明显偏高; 研究给出了青藏高原近地层与边界层动力、热力结构及其湍流、对流云特征可构成青藏高原地区边界层的综合物理图像。追踪分析研究发现, 连续成串从青藏高原中部或东部发生、发展的对流云团族呈显著东移的特征, 认为长江暴雨洪水的初始对流云系统可追溯到青藏高原; 研究发现, 在适当的云天条件下, 在青藏高原上可观测到极大的太阳总辐射、有效辐射和地表净辐射。青藏高原地面反照率的变化产生热源、热汇的区域影响效应, 这种源汇带来季节性和区域性的变化将进一步影响到大气中长波波形的季节尺度变化, 研究还强调指出青藏高原雪盖的年度变化的反馈作用表现对行星尺度环流特征的影响, 在热带洋面也产生对SST异常的相互作用与影响; 青藏高原与亚洲季风系统影响研究取得显著进展; 研究发现, 青藏高原“感热气泵” (SHAP) 的有效工作导致了青藏高原地区由冬到夏大气环流的突变及南亚高压的突然北跳, 并维持着亚洲季风期; 研究揭示出青藏高原周边“大三角”区域是影响我国长江中下游暴雨的水汽输送关键区, 揭示在青藏高原地区及其东部水汽输送的“转运站”特征。水汽流向东的“转运”效应对长江梅雨期洪涝形成甚为重要; 青藏高原大气物质输送及其臭氧异常特征研究取得进展, 研究发现夏季在青藏高原上大气臭氧总量有一明显的低值中心存在, 并且发现拉萨的臭氧递减趋势比我国东部同纬度地区大, 而拉萨位于青藏高原臭氧低值中心的区域。 相似文献
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Formation of the Summertime Ozone Valley over the Tibetan Plateau: The Asian Summer Monsoon and Air Column Variations 总被引：3，自引：0，他引：3
The summertime ozone valley over the Tibetan Plateau is formed by two influences,the Asian summer monsoon(ASM) and air column variations.Total ozone over the Tibetan Plateau in summer was ～33 Dobson units(DU) lower than zonal mean values over the ocean at the same latitudes during the study period 2005-2009.Satellite observations of ozone profiles show that ozone concentrations over the ASM region have lower values in the upper troposphere and lower stratosphere(UTLS) than over the non-ASM region.This is caused by frequent convective transport of low-ozone air from the lower troposphere to the UTLS region combined with trapping by the South Asian High.This offset contributes to a ～20-DU deficit in the ozone column over the ASM region.In addition,along the same latitude,total ozone changes identically with variations of the terrain height,showing a high correlation with terrain heights over the ASM region,which includes both the Tibetan and Iranian plateaus.This is confirmed by the fact that the Tibetan and Iranian plateaus have very similar vertical distributions of ozone in the UTLS,but they have different terrain heights and different total-column ozone levels.These two factors(lower UTLS ozone and higher terrain height) imply 40 DU in the lower-ozone column,but the Tibetan Plateau ozone column is only ～33 DU lower than that over the non-ASM region.This fact suggests that the lower troposphere has higher ozone concentrations over the ASM region than elsewhere at the same latitude,contributing ～7 DU of total ozone,which is consistent with ozonesonde and satellite observations. 相似文献
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青藏高原臭氧低谷的加深及其可能的影响 总被引：24，自引：1，他引：24
通过分析 TOMS(1 979～ 1 992 )资料发现 :(1 )青藏高原的臭氧不仅存在递减趋势 ,而且是一个递减的强中心 ,这个递减的强中心是同纬度地区 3个递减中心之一 ;(2 )夏季青藏高原臭氧低谷有加深的趋势 ,其递减率最大值为 - 0 .336% /a;加深区域为 2 9～ 33°N,78～ 94°E。另外 ,分析 SAGE 资料的结果表明 :青藏高原臭氧递减的强中心的形成是由于其平流层下部臭氧异常减少造成的。根据研究结果的趋势估测 :从 1 992年到 2 0 0 0年 ,夏季青藏高原紫外辐射增加大约为 1 .3%～ 2 .3% ,可能引起白内障发病率上升大约 0 .8%～ 1 .4% ,皮肤癌上升大约 3.2 %～ 5.4%。 相似文献
16.
We analysed the atmospheric total column ozone temporal and spatial distributions,by using the USA Nimbus Satellite TOMS data provided by the Goddard Space Flight Center of NASA,USA.We ploted the monthly mean total column ozone distributions over China by the averaged data from 1979 to 1991,and found that the atmospheric total column ozone contours were parallel to latitudes in winter and spring. However, from June, the lower center of atmospheric column ozone, called "ozone valley",was formed gradually over the Tibetan Plateau, as shown in Fig. 相似文献
17.
WENSHOU TIAN MARTYN CHIPPERFIELD QIAN HUANG 《Tellus. Series B, Chemical and physical meteorology》2008,60(4):622-635
The relatively low total column ozone (TCO) above the Tibetan Plateau (TP) observed in summer is only partly due to the thinness of the atmospheric column. In this paper the effect of the TP on the TCO is further investigated using satellite data [Total Ozone Mapping Spectrometer (TOMS) ozone column and Stratospheric Aerosol and Gas Experiment II (SAGE II) ozone profiles], ECMWF ERA-40 reanalysis data and a 3-D chemistry-climate model (CCM). It is found that the low TCO over the TP is also closely related to large-scale uplift and descent of isentropic surfaces implied by seasonal and longitudinal variations in the tropopause height. The variations in tropopause height, with a maximum in summer, can be driven by various processes including convective activity, air expansion as well as the monsoon system. While previous studies have showed an important role of troposphere-to-stratosphere transport in contributing to the observed low ozone column over the TP, the mechanism revealed in this study is an alternative amendment to the causes of the TCO low over the TP. It is also found that the monsoon anticyclone circulation induces an isentropic transport of trace gases from high latitudes towards the TP in the lower stratosphere and hence modifies tracer distributions. For the vertical distribution of ozone, the modulation by the TP is most significant below ∼20 km, that is, in the upper troposphere and lower stratosphere (UTLS). The smaller differences in NO x between Eastern TP and TP compared to large dynamically caused differences in ozone and methane imply the TCO low over the TP is mainly due to transport processes rather than chemistry. 相似文献
18.
Summary In this paper, the thermal features of the atmosphere over the Tibetan Plateau in summer and their effects on the general circulation are reviewed. Some recent research results are reported. It is shown that the Plateau acts as a heat source in summer. Particularly the strong surface heating makes the air stratification very unstable and produces strong near-surface convergence and positive vorticity and upper layer divergence and negative vorticity. Intense convective activity generated thereby not only maintains such particular large-scale circulation pattern over the Plateau, but also transports large amounts of sensible heat, moisture, chemical pollutants, as well as air with low ozone concentration from near-surface layers to upper layers. A minimum centre of total ozone concentiation and a huge upper layer anticyclone with a warm and moist core are thus observed over the Plateau in summer. The strong divergent flow and anticyclonic vorticity source in the upper atmosphere have a strong influence on the general circulation over the world via meridional as well as longitudinal circulations, and energy, dispersion on a spherical surface. It is shown that the surface sensiole heating of the Plateau is essential for the occurrence of the abrupt seasonal change of the general circulation there, and for the persisten maintenance of the Asian monsoon. It is also reported that the elevated heating of the Tibetan Plateau together with its mechanical forcing cause the early onset of the Asian monsson to happen over the eastern coast of the Bay of Bengal, which then generates a favorable circulation background for the monsoon onset over the South China Sea. The Indian monsoon onset flows aftervards.With 13 FiguresWhile I visited USA in the summer of this year (97) the sad news of the death of Professor Riehl came to me. This was a great shock to me. Herb was my esteemed colleague and friend. During the later half of my stay at the University of Chicago in the 40s I spent most of the time with Herb and worked with him. Every weak we have several discussion through which I learnt a lot from him. I cannot forget our discussions in one morning. This discussion helped me to formulate a paper The circulation of the high troposphere over China in the winter of 1945–1946 which was published in Tellus (1950). This paper demonstrated for the first time the existence of a strong jet stream around the southern periphery of Tibetan Plateau. This jet stream is usually called southern jet stream in China, because there is also a northern one to the north of the Tibetan Plateau, These two jet streams merge into one downstream of the plateau forming the stronges jet stream in the northern hemisphere. This Tellus paper and a paper by Bolin, which also appeared in Tellus (1950), stimulated my interest in studying the role of the Tibetan Plateau in the general circulation for several decades. Because of Herb's stimulation, a colleague of mine and I write this review article in the volume in memorizing Herb's big contribution to meteorology.Because of the adoption of Pinyin in the 1960s, Yeh T. C. became Ye D.-Z 相似文献