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41.
An examination of typical tropospheric ozone variability on daily, monthly, annual and interannual timescales and instrumental precision indicates that the current ozonesonde network is insufficient to detect a trend in tropospheric ozone of 1% per year at the 2 level even at stations with records a decade in length. From a trend prediction analysis we conclude that in order to detect a 1% per year trend in a decade or less it will be necessary to decrease the time between observations from its present value of 3–7 days to 1 day or less. The spatial distribution of the current ozonesonde stations is also inadequate for determining the global climatology of ozone. We present a quantitative theory taking into account photochemistry, surface deposition, and wind climatology to define the effectively sampled region for an observing station which, used in conjunction with the instrumental precision and the above prediction analysis, forms the basis for defining a suitable global network for determining regional and global ozone climatology and trends. At least a doubling of the present number of stations is necessary, and the oceans, most of Asia, Africa, and South America are areas where more stations are most needed. Differential absorption lidar ozone instruments have the potential for far more frequent measurements of ozone vertical profiles and hence potentially more accurate climatology and trend determinations than feasible with ozonesondes but may produce a (fair weather) biased data set above the cloud base. A strategy for cloudy regions in which either each station utilizes both lidars and sondes or each station is in fact a doublet comprised of a near-sea-level lidar and a proximal-mountain-top lidar could serve to minimize this bias.  相似文献   
42.
A bifurcation phenomenon with relevance to atmospheric chemistry is discussed. The gasphase reactions in the troposphere exhibit two types of temporal evolution which are controlled by the strength of the source,Q, of nitric oxide, NO, via the nonlinear chemical coupling between the hydrogen oxides and nitrogen oxides chemistry. IfQ remains below a threshold value, all short-lived species, including NO, approach steady-state concentrations, while above the threshold bifurcation to another state with increasing (nonstationary) NO concentrations accompanied by a depletion of the OH and HO2 abundances takes place.  相似文献   
43.
臭氧和平流层动力学的相互作用   总被引:1,自引:0,他引:1  
讨论了给定的南极春季臭氧洞(取自1979—1985年臭氧减少的观测结果)对二维平流层—对流层模式中温度和环流的影响。11月份,南极上空约17km处,温度最多可降低6℃。这种温度变化引起的平均经向环流对臭氧洞起填塞作用,不过,这种影响很小,每年仅产生14DU的变化。观测事实表明,近年来10月份,南半球波活动减弱。为此,我们作了南半球波作用全年都减少一半,并考虑了臭氧洞的数值试验。结果表明,臭氧柱在11月份76°S减少了44DU,在赤道却增加了12DU。  相似文献   
44.
利用地面遥感O3垂直分布的逆转方法〈C〉测量出的北京上空O3剖面资料,对雨云7号卫星的SBUV系统测量的同地区的O3垂直分布数据进行了订正.对订正后的长达8年(1979-1986年)的完整的SBUV资料进行了较为仔细的分析,得出了这一时期内的O3垂直分布长期演变呈下降趋势.并在上层O3含量的季节变化特征和周期振荡等方面,有新的发现,得出一些有意义的结果.  相似文献   
45.
北半球臭氧总量与平流层环流关系的分析   总被引:2,自引:7,他引:2  
郑光  吴统文 《高原气象》1991,10(3):277-286
  相似文献   
46.
We show that photochemical processes in the lower half of the troposphere are strongly affected by the presence of liquid water clouds. Especially CH2O, an important intermediate of CH4 (and of other hydrocarbon) oxidation, is subject to enhanced breakdown in the aqueous phase. This reduces the formation of HO x -radicals via photodissociation of CH2O in the gas phase. In the droplets, the hydrated form of CH2O, its oxidation product HCO2 , and H2O2 recycle O2 radicals which, in turn, react with ozone. We show that the latter reaction is a significant sink for O3. Further O3 concentrations are reduced as a result of decreased formation of O3 during periods with clouds. Additionally, NO x , which acts as a catalyst in the photochemical formation of O3, is depleted by clouds during the night via scavenging of N2O5. This significantly reduces NO x -concentrations during subsequent daylight hours, so that less NO x is available for O3 production. Clouds thus directly reduce the concentrations of O3, CH2O, NO x , and HO x . Indirectly, this also affects the budgets of other trace gases, such as H2O2, CO, and H2.  相似文献   
47.
On 1 February 1989, -83.5°C was recorded in 27.8 hPa over Hohenpeißenberg, the lowest temperature in the 22-year series. This was measured together with a very low total ozone amount of 266 DU. This may be compared with nearly twice this amount on 27 February 1989. The situation was very unusual: following an extremely cold winter in the Arctic stratosphere, the stratospheric cold pole was located over southern Scandinavia on 1 February in a very southerly position. The analyzed temperatures of -92 °C in 30 hPa were also unusual. Even though the low ozone amounts over Hohenpeißenberg were probably dynamically caused, an additional very small ozone decrease due to heterogeneous reactions in altitudes from 23–28 km, where the temperatures lie below -80 °C, cannot be ruled out. Extinction measurements by the orbitting SAGE II instrument indeed show polar stratospheric clouds over Europe near 50° N during the period 31 January–2 February. Also, polar stratospheric clouds were previously observed over Kiruna at similarly low temperatures and signs of a corresponding small ozone decrease were noted there.  相似文献   
48.
北京地区太阳紫外辐射的观测与分析研究   总被引:10,自引:2,他引:10  
白建辉  王庚辰 《大气科学》1994,18(3):341-347
利用北京地区太阳辐射和其它常规气象观测资料,得到了到达地面的太阳紫外辐射的计算公式,并将计算值与观测值进行了比较,两者吻合得比较好。最后给出了北京地区地面太阳紫外总辐射的变化趋势,计算结果表明,地面太阳紫外总辐射对大气浑浊度的变化比对大气臭氧总量的变化敏感得多。  相似文献   
49.
气象因子对近地面臭氧污染影响的研究   总被引:15,自引:0,他引:15  
徐家骝  朱毓秀 《大气科学》1994,18(6):751-757
本文通过对1993年春季和春夏之交的O3浓度逐日变化、日变化和气象因子关系的分析,提出了影响O3浓度的主导气象因子和不同情况下形成高浓度O3的主要因子,提出了大风速对逐日变化中O3浓度特高及浓度日变化峰值的重要作用,并指出高温、低湿、小风并不是在所有情况都是促成高浓度O3的因子。另外,雾也可以成为近地面O3浓度增值的因素,主要原因是雾内湍流发展将高浓度O3大量输向下方。  相似文献   
50.
The paper discusses the potential effects on the ozone layer of gases released by the engines of proposed high altitude supersonic aircraft. The major problem arises from the emissions of nitrogen oxides which have the potential to destroy significant quantities of ozone in the stratosphere. The magnitude of the perturbation is highly dependent on the cruise altitude of the aircraft. Furthermore, the depletion of ozone is substantially reduced when heterogeneous conversion of nitrogen oxides into nitric acid on sulfate aerosol particles is taken into account in the calculation. The sensitivity of the aerosol load on stratospheric ozone is investigated. First, the model indicates that the aerosol load induced by the SO2 released by aircraft is increased by about 10–20% above the background aerosols at mid-high latitude of the Northern Hemisphere at 15 km for the NASA emission scenario A (the NASA emission scenarios are explained in Tables I to III). This increase in aerosol has small effects on stratospheric ozone. Second, when the aerosol load is increased following a volcanic eruption similar to the eruption of El Chichon (Mexico, April 1982), the ozone column in spring increases by as much as 9% in response to the injection of NO x from the aircraft with the NASA emission scenario A. Finally, the modeled suggests that significant ozone depletion could result from the formation of additional polar stratospheric clouds produced by the injection of H2O and HNO3 by the aircraft engines.  相似文献   
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