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1.
In July–October 2006 and 2007, combined measurements of geoacoustic emission in the range of 2.0–6.5 kHz, the electric field
in the atmosphere near the ground, and meteorological values were carried out in Kamchatka. Using the nonparametric method
of Spearman’s correlation analysis, the relationship between their average hourly values was examined. After excluding results
of bad weather (rain, strong and moderate wind, low atmospheric pressure), a highly important negative relation between disturbances
in geoacoustic emission and the electric field were detected. Most probably, it was caused by amplification of the strain
of near-surface sedimentary rocks at the observation point during a seismotectonic process. The revealed relation is evidence
for another manifestation of the lithosphere’s influence on surface atmosphere in a seismoactive region. 相似文献
2.
Wind power has become one of the fastest growing renewable energy. With the large-scale deployment of wind farms in the world, people have started to pay attention to the impact of wind farms on the ecological environment and climate. This paper summarized the impact of wind farms on climate and ecological environment by investigating relevant literature: In the areas of wind farms, on the one hand, the set-up of wind turbines changes original aerodynamic roughness height and strengthens the dragging of the land surface against turbulence, directly affecting the turbulent motion of the boundary layer, resulting in the changes of intensity and pattern of material energy and water vapor exchange between land surface and near-surface atmosphere, further affecting the atmospheric circulation and climate. On the other hand, wind turbines convert the majority of the wind kinetic energy into electric energy, which produces the wake effect of the wind turbine. The budget patterns and spatial and temporal distribution of large-scale kinetic energy in the boundary layer are changed correspondingly, generating changes in various fluxes (heat flux, water vapor flux, etc.) in the atmosphere, which affect temperature, precipitation, and wind speed. Generally, the warming or cooling effect of wind farms on the near-surface is related to the stability of atmosphere. However, simulations in the global climate model showed that the average impact of wind farms on global climate is small, much smaller than the expected changes in greenhouse gas emissions and the interannual changes in natural climate.Wind power emits almost no carbon dioxide and pollutants. Compared with other traditional energy sources, it reduces water consumption but may generate some negative ecological impacts such as animal habitats, bird collisions, and noise, vision impact. However, some measures can be taken to mitigate these adverse effects. 相似文献
3.
Doklady Earth Sciences - Results from instrumental observations of geomagnetic variations and variations in the electrical characteristics of the surface atmosphere (electric field, atmospheric... 相似文献
4.
During the period of October 1–18, 2009, 41 km southwest of Petropavlovsk-Kamchatsky, in the intersection zone of tectonic
faults of various orders, simultaneous recording of the geoacoustic emission, gradient of the atmospheric electric field’s
potential, strains of the Earth’s surface, atmospheric pressure, wind speed, and rain intensity was made. It was found for
the first time that anomalous disturbances of high-frequency geoacoustic emission and atmospheric electric field near the
Earth’s surface originate as a simultaneous response to extension of near-surface sedimentary rocks. In the case of compression,
only disturbances of geoacoustic emission occur. Anomalies were recorded under quiet weather conditions and with rocks strains
being two orders greater than those of tidal ones. 相似文献
5.
Electrode layer or electrical boundary layer is one of the charge generators in the global atmospheric electric circuit. In
spite of this we find very few model studies and few measurements of it in the literature. Using a new technique it is shown
that in this layer, the space charge density varies exponentially in vertical. A new experimental method based on the surface
measurements is discussed to determine all the characteristic scales and an average electrical and meteorological state of
an electrode layer. The results obtained are in good agreement with the previous studies. So, it is suggested that an exponential
space charge density profile will no longer be an assumption in the case of electrode layer studies. The profiles of atmospheric
electric field and electrical conductivity are also derived and a new term named as electrode layer constant is introduced. 相似文献
6.
Results of a study of the influence of solar-type host stars superflares on the gas dynamics of the extended envelopes of giant exoplanets are presented. During flare events, the radiation intensity of the host star in the extreme ultraviolet and soft X-ray can increase by several orders of magnitude for a short time, leading to strong local heating of the exoplanet atmosphere on the side facing the star, with the formation of shocks in the atmosphere. Computations of the gas-dynamical response of the atmosphere of the hot Jupiter HD 209458b to characteristic superflares of solar-like stars were carried out earlier in [1] using a one-dimensional aeronomical model correctly taking into account heating and chemical processes in the atmosphere. To investigate the outflow of atmospheric gas, the results obtained with this onedimensional model were used as simple boundary conditions for computations of the three-dimensional flow structure after a flare. The results of these three-dimensional gas-dynamical computations show that the mass ejection of the flare increases the size of the envelope over several hours, which could be detected with existing observing facilities. It is shown that the mass-loss rates for the most powerful superflare considered could be enhanced by an order of magnitude over several tens of hours after the flare. 相似文献
7.
The ion-aerosol balance equations are solved to get the profiles of atmospheric electric parameters over the ground surface in an aerosol-rich environment under the conditions of surface radioactivity. Combining the earlier results for low aerosol concentrations and the present results for high aerosol concentrations, a relation is obtained between the average value of atmospheric electric space charge in the lowest ~2 m, the surface electric field and eddy diffusivity/aerosol concentration. The values of eddy diffusivity estimated from this method using some earlier measurements of space charge and surface electric field are in reasonably good agreement with those calculated from other standard methods using meteorological or electrical variables. 相似文献
8.
This paper considers characteristic features of the composition and distribution of chemical elements in aerosols over the Northern Caspian, which can be used for a more reliable prediction of possible negative consequences of atmospheric pollution related to the beginning of the large-scale exploitation of oil and gas deposits in the shelf zone of the Caspian Sea. It was shown that the contents of aerosols, their grain-size composition, and major-element composition change under the influence of (1) transboundary transport of terrigenous dust by air masses, (2) variations in the intensity of turbulent and convective mixing in the near-surface atmosphere, and (3) variations in air humidity. 相似文献
9.
Measurements of 18O in atmospheric CO 2 have been used to partition site-level measured net ecosystem CO 2 fluxes into gross fluxes and as a constraint on land surface biophysical processes at regional and global scales. However, these approaches require prediction of the δ 18O value of the net CO 2 flux between the soil and atmosphere (δ F), a quantity that is difficult to measure and accurately predict. δ F depends on the depth-dependent δ 18O value of soil water (δ sw), soil moisture and temperature, soil CO 2 production, and the δ 18O value of above-surface CO 2. I applied numerical model manipulations, regression analysis, a simple estimation method, and an analysis of the characteristic times of relevant processes to study the impacts of these parameters on δ F. The results indicate that ignoring δ sw gradients in the near-surface soil can lead to large errors. In particular, in systems where δ sw gradients exist, generalizing previous experimental observations to infer that a bulk (e.g., 5-10 cm or 5-15 cm depth) estimate of δ sw can be used to estimate δ F is problematic. These results highlight the need for further experiments and argue for the importance of accurately resolving near-surface δ sw in the context of partitioning ecosystem CO 2 fluxes and CO 2 source attribution. 相似文献
10.
This paper presents a numerical model for the effect of near-surface inhomogeneities over a one-dimensional horizontally layered geoelectric section and the distortions they cause during magnetotelluric sounding (MTS). The electromagnetic field within the layer of near-surface inhomogeneities is calculated using the Trefftz method. Expressions are derived for the boundary conditions on the day surface and on the roof of the underlying inhomogeneity of a horizontally layered medium. These boundary conditions allow for the excitation of TM-mode fields by subsurface inhomogeneities and their penetration into the atmosphere and the underlying medium. The spatial distribution and characteristics of galvanic and inductive distortions over different time periods during MTS have been studied. Experimental data show that accounting for galvanic distortions is possible with synchronous recording of the distribution of components of the electric and magnetic fields in a limited area of the Earth’s surface. 相似文献
11.
卫星信号从GPS卫星发射到地面的过程中经过了以充满大气为介质的空间。电磁波在这种变化的介质中传播,其传播的方向、速度、强度都可能随时改变。本文简略地介绍了大气传播延迟的产生及其对GPS测量的影响,并就GAMIT软件对大气传播延迟的控制方法和所采用的改正模型做一简单介绍,并对减弱和消除大气传播延迟的方法和手段进行了讨论。 相似文献
12.
Doklady Earth Sciences - Variations in the electric field and atmospheric current in the surface atmosphere at middle latitudes during 58 strong magnetic storms that occurred from 2016 to 2019 are... 相似文献
13.
Hydrological, chemical and meteorological data collected during the years 2006–2007 at Carburangeli Cave (Italy) have provided new insights on the near-surface cycle of carbon dioxide, particularly concerning the role played by fractures and karst conduits. Carbon dioxide is trapped in the underground atmosphere essentially when its temperature is lower than the outer one. By contrast, convective air circulation disperses all the excess CO 2 in the external environment when the thermal differential is inverted. The network of fractures and karst conduits then works, in the vadose zone, as a re-circulator of CO 2 from the soil to the atmosphere. The total amount of CO 2 fixed in the underground is controlled, during the wet season, by the amount of infiltrating waters, which act as the main carrier of CO 2 in the subsoil. By contrast, during the dry season, gravitational drainage is responsible for the accumulation of carbon dioxide in the underground voids. The quantitative balance demonstrated that the degassed CO 2 amounts are one order of magnitude higher than the dissolved CO 2. In light of this, if the near-surface outgassing processes are not taken into account, CO 2 budgets may be affected by significant errors. 相似文献
14.
为探讨湖南省益阳市岳家桥地质灾害现状,以区内典型岩溶发育区为研究对象,通过长剖面高密度电法、视电阻率联合剖面法等地球物理方法,研究了地层电性响应特点,利用钻孔数据和综合电法勘探数据建立了三维地层结构模型,揭示了典型区域近地表电性结构形态,构建了区内三维地层构造格架,圈定了岩溶发育范围,并评价了地质灾害程度.研究表明:因地制宜地利用综合电法勘探,有助于在我国南方含水较多的岩溶发育区快速、有效地进行灾害范围的圈定和评价. 相似文献
15.
The general evolution of planets in the Solar System is discussed with a focus on the structure and history of Venus compared with the Earth. The history of the planets of the terrestrial group has been similar and included at least six correlated stages. Many common features the terrestrial planets shared in their early and late evolution have been due to their common origin from the protoplanetary gas-and-dust nebula and plume magmatism widespread on all the planets of the terrestrial group. The characteristic features of the structure and evolution of Venus are most brightly manifested in the specific composition of its atmosphere and of plume magmatism. Venus, with its surface as hot as 450 °C and the near-surface pressure of 92-93 bars, has a hot and dense atmosphere 93 times that of the Earth in mass. Most of its atmospheric mass (99%) belongs to the 65-km thick troposphere consisting of CO 2 (96.5%) and N 2 (3.5%). The upper troposphere includes a 25-30 km thick cloud layer composed mainly of sulfuric acid droplets, water vapor, and SO 2. At a height of 49.58 km, the clouds approach the conditions of the terrestrial surface and might be hospitable to bacterial life. Volcanism, the most active and widespread process of Venusian geology, maintains continuous SO 2 emission. There are diverse volcanic edifices on Venus, which are most often large and are similar to the Earth’s plume-related volcanoes. The evolution before 1 Ga, as well as the share and the role of alkaline rocks and carbonatites among its volcanics, are among the most debatable issues about Venus. Being located closer to the Sun, Venus cooled down more slowly and less intensely than the Earth after the primary accretion. In the Proterozoic, it began heating and reached its present state at ~ 1 or 2 Ga. In the future, as the Sun becomes a red giant, the Earth is predicted to begin heating up in 500-600 Myr to reach the temperature of present Venus in about 1.5 Gyr. 相似文献
16.
利用观测试验资料, 对比分析了夏季典型晴天敦煌绿洲与周围荒漠戈壁背景近地面层大气特征的差异. 结果表明: 绿洲具有降温、保湿、风屏等效应, 地表温度和近地面层大气温度明显要比周围荒漠的低, 近地面层大气湿度要明显比周围荒漠的大, 近地面层大气风速和摩擦速度要比周围荒漠的小, 近地面层感热通量比周围荒漠小1/5, 近地面层潜热通量比周围荒漠大 10 倍左右. 同时, 绿洲与周围荒漠相比有比较可观的下沟运动, 这会对绿洲的能量和水分输送有贡献. 绿洲的 Bowen比大约是周围荒漠戈壁的1/20, 相差一个量级, 这说明绿洲和周围荒漠的气候特征相差十分明显. 相似文献
17.
Most modelling endeavours concerning the CO 2-climate problem address only the question of the climatic response to increasing atmospheric carbon dioxide, while the amounts of other atmospheric gases remain fixed. But associated changes, either climatologically or anthropogenically induced, of minor atmospheric constituents can also be of significance in producing a substantial global warming. We have analysed the climatic response to changes in a number of atmospheric trace gases as they may enhance or counteract CO 2-induced warming if their abundance should change. A comparison of the increase in equilibrium global-mean surface temperature due to plausible changes in the concentration of several trace gases in the atmosphere based on our calculations with a one-dimensional radiative-convective model is presented in this paper. Our results indicate that roughly 35% of global surface warming could be due to changes in trace gases other than CO 2 and water vapour. The possible climatic consequences of the ongoing anthropogenic changes in the minor constituents of the atmosphere are also discussed. 相似文献
18.
It was shown that the history of the biosphere is closely related to processes caused by low solar luminosity. Solar radiation is insufficient to maintain the Earth’s surface temperature above the freezing point of water. Positive temperatures are kept owing to the presence of greenhouse gases in the atmosphere: CO 2, CH 4, and others. Certain stages in the development of the biosphere and climate are related to these effects. Methane was the main carbon-bearing gas in the primordial atmosphere. It compensated the low solar luminosity. Life originated under the reduced conditions of the early Earth. Methane-producing biota was formed. Methane remained to be the main greenhouse gas in the Archean. The release of molecular oxygen into the atmosphere 2.4 Ga ago resulted in the disruption of the established mechanism of the compensation of the low solar luminosity. Methane ceased to cause a significant greenhouse effect, and the content of carbon dioxide was insufficient to play this role. A global glaciation began and had lasted for approximately 200 million years. However, the increasing CO 2 content in the atmosphere reached eventually a level sufficient for the compensation for the low solar luminosity. The glaciation period came to an end. Simultaneously, a conflict arose between the role of CO 2 as a gas controlling the thermal regime of the planet and as an initial material for biota production. As long as the resource of biotic carbon was inferior to that of atmospheric CO 2, the uptake of atmospheric CO 2 related to sporadic increases in biologic production was insufficient for a significant change in the thermal regime. This was the reason for a long-term climate stabilization for 1.5 billion years. By 0.8 Ga, the resource of oceanic biota reached the level at which variations in the uptake of atmospheric CO 2 related to variations in the production of organic and carbonate carbon became comparable with the resource of atmospheric CO 2. Since then, an oscillatory equilibrium has been established between the intensity of biota development and climate-controlling CO 2 content in the atmosphere. Glaciation and warming periods have alternated. These changes were triggered by various geologic events: intensification or attenuation of volcanism; growth, breakup, or migration of continents; large-scale magmatism; etc. A new relation between atmospheric CO 2 and biotic carbon was established in response to the emergence of terrestrial biota and the appearance of massive buffers of organic carbon on land. The interrelation of the biosphere and climate changed. 相似文献
19.
Variations in the atmospheric carbon dioxide concentration and the average global near-surface air temperature are compared over the last 50-year period. It turns out that, within the interannual time scales, the carbon dioxide concentration variations generally lagged behind the corresponding temperature variations. However, within time scales of more than 40 years in the 1980s–1990s, when the growth of CO 2 and temperature accelerated, carbon dioxide was in the lead. This fact indicates that atmospheric pollution actually could have begun to affect the climate at that time. 相似文献
20.
The atmospheric abundances of various chemical elements and other atmospheric parameters of four stars belonging to the HR 1614 moving cluster are determined and analyzed using a single technique. For three of the stars, the derived atmospheric parameters are typical of stars of their types, and their elemental abundances are close to those determined earlier for these and other stars of the moving cluster. However, the atmospheric parameters derived for the red dwarf HD 32147 would be more typical of a giant, and its metallicity is much lower than is characteristic of stars of this moving group. 相似文献
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