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1.
This paper analyzes the relationship between meteorological catastrophic factors and gross domestic product (GDP) growth rate of Nanjing city (China). The sample spans the period 1980–2010, including GDP growth rate and meteorological catastrophic factors (extreme precipitation, extreme temperature and extreme wind speed). We utilize econometric methods to take co-integration analysis and Granger causality test among GDP growth rate and the time series of meteorological catastrophic factors of Nanjing city processed by buffer operators. Finally, the paper shows the short-term changes in minimum atmospheric pressure, extreme high temperature, and minimum relative humidity, which has a positive impact on GDP; the cumulative effect of extreme precipitation and GDP affects each other to some extent, they are mutually Granger causes. Moreover, at the 95 % confidence level, we believe that maximum wind speed is the Granger causation of GDP growth rate. 相似文献
2.
采用国际地球自转服务中心(IERS)发布的日长变化(Length of the Day,LOD)数据和美国国家地震信息中心(NEIC)公布的地震目录中的震级在5.0级(含5.0级)以上的地震数据,对1973年以来的每日地球自转变化时间序列与地震时间序列之间的Granger因果关系进行检验,结果表明:地球自转变化与地震之间存在着双向Granger因果关系,即地球自转变化可能导致地震发生,地震也会对地球自转变化产生影响,检验结果暗示了两者之间可能存在着复杂的动力机制。 相似文献
3.
中纬度海气相互作用研究进展 总被引：9，自引：0，他引：9
回顾了中纬度海气相互作用的研究现状,分析了长期以来该项研究进展缓慢的原因和近十几年来的研究成果,结果指出:中纬度海洋在全球气候变化中有着重要的作用;冬季中纬度海气相互作用的强信号是冷空气强度;中纬度海洋强暖流区海气能量交换异常对同期和后期(半年至一年)北半球范围内的大气环流型有重要影响;当冬季黑潮和湾流海域海洋对大气同时异常多或异常少加热时,易形成夏季长江中下游偏旱或偏涝的环流形势。最后还提出,深入研究中纬度海气能量系统异常对大气环流影响及其物理机制,是今后海气相互作用研究的重要内容,其结果将为短期气候预测提供理论依据。 相似文献
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Observations and box model analysis of radon-222 in the atmospheric surface layer at L’Aquila,Italy: March 2009 case study 总被引：1，自引：1，他引：0
Giovanni Pitari Eleonora Coppari Natalia De Luca Piero Di Carlo 《Environmental Earth Sciences》2014,71(5):2353-2359
Two years of radon-222 observations collected at L’Aquila (Italy) in the atmospheric surface layer during 2004–2006 were analyzed in correlation with meteorological data and other atmospheric tracers. A box model was developed to better understand the mechanisms of diurnal and seasonal variability of the tracer and to indirectly assess the magnitude of the monthly averaged radon soil flux in the L’Aquila measurement site. The model was successfully validated with measurements, with a 0.8 average correlation coefficient between hourly values for the whole period of radon observations. Measurements taken during March 2009 were analyzed to find possible signs of perturbation due to the ongoing seismic activity that would have reached its peak on the 6 April 2009 destructive earthquake. Contrary to the professed (and unpublished) dramatic increases of radon activity unofficially announced to the inhabitants at that time, the study presented here shows that no radon activity increase took place in L’Aquila with respect to a previous ‘seismically unperturbed’ year (same month with similar meteorological conditions), but that an average 30 % decrease was experienced. This conclusion is reached from a direct comparison of observed data and also as a result of the previously validated radon box model constrained by actual meteorological data, from which an indirect estimate of a 17 % reduction of the radon soil flux is obtained. 相似文献
6.
Piero Di Carlo Giovanni Pitari Natalia De Luca Domenico Battisti 《Environmental Geology》2009,58(2):431-436
Two years of in situ radon concentration measurements in the atmospheric surface layer have been collected in a central Italy
town (L’Aquila), located in the Aterno river valley. These data have been analyzed in order to study the controlling mechanisms
of surface radon abundance; observations of coincident meteorological parameters confirmed the role of dynamics on the local
removal rate of this tracer. The relatively high negative correlation of hourly data of surface wind speed and radon activity
concentration (R = −0.54, on annual scale) suggests that dynamical removal of radon is one of the most important controlling processes of
the tracer accumulation in the atmospheric surface layer. An attempt is made to quantify the precipitation impact on radon
soil fluxes. No anticorrelation of radon and precipitation comes out from the data (R = −0.15), as in previous studies. However, since the main physical parameter affecting the ground radon release is expected
to be the soil accumulation of water, snow or ice, the emission flux has also been correlated with soil moisture; in this
way a much clearer anticorrelation is found (R = −0.54). 相似文献
7.
在城市化与土地利用结构的协调发展成为焦点问题的时代背景下,以新疆乌鲁木齐市为研究区域,采用Johansen协整检验和Granger因果关系分析法,对乌鲁木齐市2000-2015年的城市化水平及5类代表性城市用地结构变化数据进行了处理,并对城市化与用地结构进行了因果关系分析。结果表明：（1）2000-2012年,乌鲁木齐市城市化水平由84.82%降至77.12%,呈下降趋势;2013-2015年由77.73%升至81.62%,呈上升趋势,造成这一现象的主要原因是非农业人口增长速率相对于农业人口增长速率较慢;（2）2000-2015年各类用地所占比例变化情况如下：居住用地比例均在26%以上,明显高于其他用地;工业用地比例较为稳定,均为15%~19%;公共设施用地2014-2015年明显下降,即从平均比例11.46%降至5.03%;城市道路用地比例较稳定,均为5.8%~7.5%;绿地比例呈上升趋势,由20.01%升至30.94%;（3）城市化与居住用地之间的Granger因果关系不明显,工业用地、公共设施用地、城市道路用地是引起城市化的Granger原因,城市化是绿地的Granger原因。对乌鲁木齐市城市化与土地利用结构进行因果关系分析,对城市用地格局的改善、土地利用战略以及有关政策法规的制定具有一定的参考意义。 相似文献
8.
Summary A survey of radon in soil gas emissions was carried out in the Carnmenellis area of Cornwall to establish the location and extent of any major radon gas concentrations. Measurements of soil radon gas levels showed considerable variation. Radon emission variation with respect to atmospheric pressure was monitored but results showed no correlation between the variables. A survey of schools in the region with high indoor radon concentrations was carried out for comparison with the results of the main survey. A good correlation was found between the two surveys, suggesting that broad-based radon hazard mapping on a local scale may be feasible. 相似文献
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In 1996–1997, indoor radon values of more than 40,000 Bq/m3 and large seasonal and geographical variations in indoor air radon were reported from a residential area located on a highly permeable ice-marginal deposit. Geochemical analyses of bedrock, groundwater and sediments and comparisons between indoor radon values and soil radon values indicate that the indoor radon concentrations in this area are strongly affected by subterranean airflows caused by temperature differences between soil air and atmospheric air. The airflows concentrate the radon-laden soil air towards the topographic highest part of the deposit in winter and towards the topographic lowest part in summer. In areas where subterranean airflows are likely to occur, radon measurements performed both in summer and in winter provide the best estimate of annual average indoor radon concentrations, and assessments of indoor radon concentrations based on single soil gas measurements are not recommended. 相似文献
11.
Sedat İnan Alican Kop Hasan Çetin Furkan Kulak Zümer Pabuçcu Cemil Seyis Semih Ergintav Onur Tan Ruhi Saatçılar M. Nuri Bodur 《Natural Hazards》2012,62(2):575-591
Soil gas radon release patterns have been monitored continuously for more than 3 years in the Eastern Mediterranean Province (EMP) (Southern Turkey), alongside regional seismic events, providing a multidisciplinary approach. In the period from January 2008 to January 2011, 14 earthquakes M L ≥4 occurred in the study area. By monitoring the sites for more than 3 years, the site-characteristic patterns of soil radon emanation of each site have become evident. Radon emanation data show seasonal (semi-annual) variation characteristics; high soil radon values are between May and October and low soil radon values are between November and April. With available rainfall data, the soil gas radon data can be more reliably evaluated. It is shown in this paper that if radon emanation data are available over sufficiently long periods of time and baseline data (and their seasonal variations) are known with certainty for each monitoring site, then the observation of positive anomalies might provide a correlation or connection to seismic activity. 相似文献
12.
S. Falsaperla B. Behncke H. Langer M. Neri G. G. Salerno S. Giammanco E. Pecora E. Biale 《International Journal of Earth Sciences》2014,103(1):297-313
During the spring of 2007, paroxysmal activity occurred at the Southeast Crater of Mt. Etna, always associated with sharp rises in the amplitude of the volcanic tremor. Activity ranged from strong Strombolian explosions to lava fountains coupled with copious emission of lava flows and tephra. During inter-eruptive periods, recurrent seismic unrest episodes were observed in the form of temporary enhancements of the volcanic tremor amplitude, but they did not culminate in eruptive activity. Here, we present the results of an analysis of these inter-eruptive periods by integrating seismic volcanic tremor, in-soil radon, plume SO2 flux, and thermal data. SO2 flux and thermal radiation are envisaged as the “smoking gun,” and certifying that changes in seismic or radon data can be considered as volcanogenic. Short-term changes were investigated by pattern classification based on Kohonen maps and fuzzy clustering on volcanic tremor, radon, and ambient parameters (pressure and temperature). Our results unveil “failed” eruptions between February and April 2007 that are explained as ascending magma batches, which triggered repeated episodes of gas pulses and rock fracturing, but that failed to reach the surface. 相似文献
13.
Mechanisms of the acidification of precipitation at the expense of radiochemical effects were considered. The results of natural measurements of physicochemical and metrological parameters (pH, T, and radiation background) of atmospheric precipitation (rain and snow) are reported. The possible influence of radon radioactivity (decay energy) on physicochemical processes in the atmosphere was analyzed. A hypothesis was proposed on the mechanism of this process. 相似文献
14.
自工业革命以来全球大气CH4含量呈快速的增长趋势, 但达索普冰芯记录所显示的北半球中低纬度地区大气CH4增长的启动时间要晚于极地冰芯记录近100 a. 由于受北半球人类活动CH4排放、CH4在大气中的寿命及大气中CH4的传输等过程的影响, 最近150 a以来, 中低纬度大气CH4与南极大气CH4含量在不同的时段表现出不同的净积累量和增长速率, 且20世纪两次世界大战期间达索普冰芯记录明确显示出人类活动排放的减缓使大气CH4呈负增长. 对比研究认为, 到20世纪中叶人类活动的甲烷排放已达到极高值, 中低纬度大气中CH4增长率及年积累逐步趋于平稳且略有降低. 可以认定, 工业革命以来中低纬度地区大气CH4与南极大气CH4含量的变化在不同的时段在受控于人类活动影响的同时, CH4在大气中的行为和传输过程以及东亚中低纬度季风气候的影响决定了两地之间大气CH4含量变化存在显著的差异. 相似文献
15.
地球韵律的时空表现及动力问题 总被引：4，自引：2，他引：4
文章介绍了大洋底１５６６Ｍａ以来六个时段增生构造的划分，前五个时段平均３０Ｍａ，具一定韵律性，以此与中国大陆１７５Ｍａ以来岩浆 构造活动的分段进行了比较，它们共同的韵律时段是（３０±８）Ｍａ。文中还介绍了一组全球地震活动的分幕性及其空间展布的有趣现象，包括低、中纬度与高纬度地震２０年左右的交替活动，南、北极区地震的交替活动，Ｍｓ≥８级大震呈现正交型与斜交型全球图像的分幕性交替活动，还有地球转速加速期和减速期地震发生地区的韵律性分布等。就上述中期和短期的地球韵律表现，进行了地球韵律判定的复杂性和动力学背景的讨论，强调了地球韵律的应用和地球本体研究的重要性。 相似文献
16.
K Charan Kumar T Rajendra Prasad M Venkat Ratnam Kamsali Nagaraja 《Journal of Earth System Science》2016,125(7):1391-1397
Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth’s surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5°N and 79.2°E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon (R = – 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m?3 and 4.25±0.18 Bq m?3 for its progenies, in the study period. 相似文献
17.
大气氡测量影响因素探讨 总被引：1，自引：0，他引：1
杨亚新 《华东地质学院学报》1996,19(3):289-294
本文介绍了地壳中放射性元素的分布规律及大气中氡的来源，并着重讨论了测量大气氡浓度的影响因素，以便更好地进行放射性环境的评价及防止，避免氡对人体的危害。 相似文献
18.
Natural Hazards - The aim of this work is to study the relationship between the pre-earthquake emissions of radon and ULF/ELF (1–30 Hz) atmospheric electromagnetic radiation. The... 相似文献
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《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》2000,25(9-11):699-703
The aim of this study is to understand the seismic characteristics of fault systems, which play key roles in the geodynamics of the Mt. Etna and the ascending magma. Understanding the seismic behaviour of fault systems and their relationship to volcanic and seismic phenomena may provide a useful contribution to a better understanding of dynamic processes at Mt. Etna. The seismicity in two periods (1874–1913 and 1981–1996), which include some important eruptions, have been analysed. Quantitative analysis of seismicity has been performed. Calculating fractal dimension allows us to distinguish between random, periodic and clustered scale-invariant time distributions of volcanic events. Correlations between fractal clustering evolution at long, mid and short term and eruptive processes has been found. 相似文献