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1.
本文利用亚洲地区11个大气臭氧观测站12年(1965—1976)的臭氧总量月平均资料及相应时段里亚洲上空500mb位势高度等气象资料,采用相关分析和谐波分析等基本方法,初步研究了亚洲上空臭氧含量的某些基本时空变化规律,发现臭氧分布及其变化趋势上均有明显而确切的经向和纬向差异存在,並指出在30—35°N的纬度带上臭氧分布及变化有异常的跃变现象。  相似文献   

2.
 采用季节划分和季节突变的概念、理论及方法,对44a(1958~2001年)的大气臭氧资料及对流层顶气压场资料进行了计算,并分析了对流层顶大气臭氧的季节变化.结果发现对流层顶大气臭氧的季节变化在全球大部分区域中的突变性都比较明显,表明对流层顶大气臭氧的季节变化受到上对流层和下平流层中多种因素的影响.通过分析还发现,利用曾庆存所定义的参数RW(t)及有关的一些概念和方法确能很好地反映对流层顶大气臭氧的季节变化.  相似文献   

3.
本文分析了北京地区1979-1982年大气臭氧总量和地面气压及温度的逐日变化。分析结果表明,臭氧总量的变化与地面气压存在正相关,而与地面温度存在负相关。这种相关性在无云天气条件下最为明显。春季、冬季和秋季的资料分析结果比夏季好。臭氧总量与地面气压呈正相关,这可能是受大气水平运动和垂直运动影响的结果;臭氧总量与地面温度变化呈负相关,这里臭氧对太阳紫外辐射能的净吸收,可能起着一定作用。  相似文献   

4.
本文分析了东亚30°N和40°N上空大气臭氧总量与磁暴活动的变化特征,并采用交叉谱的方法,着重研究了第20太阳活动周内臭氧总量变化和磁暴活动的相互关系,这种相互关系随纬度而有所差异。此外,在太阳活动第20周期间,30°N上空臭氧总量月平均量和磁暴月频数的周期性变化之间存在着密切的关系,且这些变化与大气环流的某些周期韵律有很好的对应。  相似文献   

5.
本文是继文献[1]的研究之后,进一步对大气臭氧层活动与东亚大气环流及天气季节转换之间的关系所作的探讨。我们从天气和动力上简要阐述了大气环流与臭氧层活动的一般关系、对东亚上空的臭氧总量分布和季节变化。臭氧层活动与东亚天气季节转换之间的关系进行了讨论。并付臭氧总量变化与自然天气季节转换资料作了初步计算分析,结果表明。东亚上字臭氧总量的季节变化在纬向和经向上存在着差异。东亚西部中高纬地区上空的臭氧层变化与东亚季节转换有一定的联系。  相似文献   

6.
在区域气候模式的基础上引入了对流层大气化学模式,并实现两的双向反馈连接,利用该模式系统模拟中国地区对流层大气臭氧和区域气候,发现东亚季风是影响中国地区对流层大气臭氧分布的重要原因,并且对流层臭氧分布局域性较为明显。模拟也得到了模拟区域气候的四个典型月特征,并与分析资料对比验证了所得结果。此外利用大气化学模式计算的臭氧反馈到区域气候模型中,模拟对流层臭氧增加背景下。模拟区域内晴空辐射强迫的变化。  相似文献   

7.
采用交叉谱分析方法,通过年全球平均的大气臭氧总量和10.7cm大阳通量两时间序列的对比分析发现,大气臭氧的短期变化和大阳自转活动之间有着极为密切的相关关系:大气臭氧准27天周期变化和太阳10.7cm辐射通量之间存在约140°的位相差,落后时间为10.2天.//关键词  相似文献   

8.
昆明地区臭氧总量与气温间变化关系的初探   总被引:1,自引:1,他引:0  
将因子分析和谱分析方法运用于大气臭氧与气温变化的相互关系研究中,通过计算得到了影响昆明地区臭氧总量和气温状态变化的主因子,揭示了臭氧总量与气温各自存在的周期性变化,以及它们之间的相关性及位相关系,其结果为认识大气臭氧和气温这间变化的气候效应关系提供了一些事实。  相似文献   

9.
本文第一次给出了昆明地区大气臭氧层的基本状态:它的总含量,空间分布和时间变化特征。比较了昆明、北京两地的大气臭氧层的基本状态,发现平流层中下层和对流层上层是大气臭氧含量变化最活跃的区域,臭氧总量随纬度的变化也主要发生在这个区域。  相似文献   

10.
2001-03-21在昆明用电化学臭氧探空仪探测到了对流层低层异常的高浓度臭氧分布。这个个例中昆明对流层低层异常的高浓度臭氧分布特征不同于2001-03-08的昆明个例。使用NCEP分析资料、中尺度数值模式MM5模拟的大气环流数据、卫星观测的东南亚地区的生物体燃烧状况、气溶胶指数等资料,分析了这段时间的天气形势、大气环流、空气块后向轨迹以及生物体燃烧产生的烟尘轨迹,结果发现高浓度的臭氧空气来源于有生物体燃烧的南亚地区。这与以往研究中东南亚地区生物体燃烧导致华南地区对流层低层臭氧浓度异常增高有所不同。  相似文献   

11.
Climate in China during the four special periods in Holocene   总被引:9,自引:0,他引:9  
Characteristics of temperature over China during the four special periods in the Holocene, i.e. the Megathermal, the Medieval Warm Period, the Little Ice Age and the Modem Warm Period, are analyzed. The Megath-ermal period was 8.5—3.0 kaBP.the maximum temperature appeared at about 5.5—6.0 ka and 7.0 kaBP, while the temperatures were about 2X1 above the average of the latest one hundred years. During the Medieval Warm Period, from the late 9th century to the 13th century, the temperatures were warmer over eastern China. Some maximum temperatures were close to the mean value in 1880s—1970s. However, the climate in the 12th century was cold. Over the west part of China, temperatures did not show the same features as that over the east except the moderate warmth appeared during the second half of the 9th century. There were five cold spells in China during the last millennium; in the early 12th, 14th and 16th centuries, the late of 15th century, the 17th and 19th centuries. In these cold periods, the last three spells can be considered as the Little Ice Age of China, the minimum of temperature anomaly was below - 1.01 and - 0.51 for the 10 years' and 30—50 years' mean respectively. The 20th century was the warmest in the last 12 centuries, and was 0.5t wanner than the last 1200 year's mean. During the last one hundred years, the warmest period appeared in 1920s—1940s, but the highest annual temperature occurred in 1998 in which the temperature anomaly was + 1.38t with respect to the mean temperaure of 1961s—1990s.  相似文献   

12.
Recent tree-ring studies in Mongolia provide evidence of unusual warming that is in agreement with large-scal reconstructed and recorded temperaturec for the Northern Hemisphere and the Arctic.One Mongolian proxy record for temperature extends back over 1000 years and several others are over 350 years in length.Precipitation reconstructions based on thee rings reflect recent increases but also indicate that the increases are within the long-term range of varlations.Spectral analyses of recorded preciplta-tion data and the reconstructions support the hypotheses of quasi-solar periodicity in precipitation variation,previously suggested by others.  相似文献   

13.
An experiment of stability of diatomaceous silica was performed. The results show that pH value and temperature dominantly influence the stability. The pH value concerning largely dissolving diatomaceous silica is 2-3 higher than that amorphous silica due to the buffer action of coexistent clay minerals. The solubility of diatomaceous silica rises distinctly when temperature is over 40℃, which suggests the cause of distribution of large-scale diatomite deposits in the middle to high latitude areas over the world. There is no close relationship between the solubility of diatomaceous silica and time, which shows that the content of diatomaceous silica in diatomite deposits are determined by the latest environment condition since they formed and bore no relation to the time they experienced.  相似文献   

14.
决定电动机绕组绝缘寿命的基本因素是温度,目前温度保护在单相小容量电动机中应用较多,而在三相电动机中应用却很少,为此,我们设计了用蝶形过流过热保护器和埋入式过热保护器对三相电动机进行过热保护的方案。  相似文献   

15.
用M-K检验法分析了澧水流域某水文站59 a间的降水资料,发现降水有一个随着时间推移而减少的趋势.再用Hurst指数检验时间序列方法分析,发现Hurst指数为0.78±0.12,说明降水前后是相关的,而且这些数据显示存在一个30 a的非周期性变化.对这59 a期间张家界气象站共48 a的气温变化研究发现气温呈现上升趋势,且气温变化与降水量变化之间呈现反相关关系,即气温上升,降水量下降.  相似文献   

16.
Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.  相似文献   

17.
Key points on temperature change of the past 2000 years in China   总被引:6,自引:0,他引:6  
Itisimportanttostudythetemperaturechangeduringthepast 2 0 0 0 yearsforunderstandingtheis suessuchasthegreenhouseeffectandglobalwarminginducedbyhumanactivities .Chinahasadvantagesinreconstructinghistoricalclimatechangeforitsabun dantdocumentedhistoricalrecordsandothernaturalevidenceobtainedfromtreerings ,lakesediments ,icecores ,andstalagmite .SinceDr .Chulaidafounda tiononthestudyoftemperaturechangeinChinaforthepast 5 0 0 0 years[1] ,significantprogressinthestudyoftemperaturechangeofthepast 2…  相似文献   

18.
Dendroclimatological techniques were employed to investigate the relationship between Chinese Pinus(Pinus tabulaeformis Carr.) growth and climatic variability in the Mt.Yishan region of Shandong Province, China, over the past253 years. Using regression analysis, the wetness index(WI)was reconstructed for the Mt. Yishan area for the period1755–2007 AD based on tree-ring widths; predictor variables accounted for 40 % of the variance. The reconstructed timeseries displayed an increasing trend after the late 1960 s. Both the estimated and the observed WI for May–August were better correlated with precipitation than temperature during the period 1958–2007 AD, indicating that the contribution of precipitation to the WI was larger than temperature in the study area. The reconstructed WI was compared with the dryness/wetness index of China and land areas that were affected by droughts and floods using the agricultural statistics for Shandong Province. In addition, the WI time-series corresponded well with the peanut yield in Shandong Province at high frequency, which may be reasonable in the context of agriculture in Shandong. The 3-, 5- to 6- and 9- to10-year periodicities detected in the time-series suggested that the reconstructed WI in the Mt. Yishan area may be related to large-scale climate variations.  相似文献   

19.
For a better understanding of the feasibility of supercritieal fluid dyeing (SFD) and more available information for the process development, the experiments of dyeing PET textile with C.I. disperse red 60 (anthraquinone type) and C. I. disperse orange 25 (azo type) in supercritieal CO2 were carried out with a high-pressure dyeing apparatus at temperatures from 80 to 130℃ and pressure up to 31 MPa. The effect of operating conditions on color yield (K/S) was investigated in SFD experiment, and the optimum operating conditions for the above two disperse dyes were obtained as follows: the temperature 120℃, the pressure 25 MPa and the dyeing time 100 min. As compared with SFD, the conventional water dyeing (CWD) was carried out with the same dyes and textile. The results show that the better fastness, levelness and apparent color can be achieved in SFD and the SFD process has many significant advantages over the CWD process.  相似文献   

20.
根据 Sturge 和Hwang 的实验数据,通过计算机拟合、内插方法获得了所需能量范围内 13种温度的 GaAs 吸收谱。在此基础上,采用表面光伏方法在 21~320 K 温度范围内测试了不同掺杂浓度的 N型 GaAs样品的少子扩散长度。得到了一组反映少子扩散长度温度特性的实验曲线,并由实验曲线得到可用于计算不同温度下少子扩散长度Lp(T)的经验公式。  相似文献   

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