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61.
A landslide occurred in colluvial deposits at one of the lagoons of Wadi Es-Sir Sewage Treatment Plant Project (under construction) in Jordan. This paper summarizes the geotechnical investigations conducted at three lagoon sites in the project area including the failed lagoon. Results of stability analyses are presented along with recommendations to stabilize the slided lagoon and surrounding areas. 相似文献
62.
A model was developed for pollutant dispersion from a point source simulating the Hadera (Israel) power plant stack. The model is based on the NCAR mesoscale meteorological MM4 model that provides the wind fields and coefficients of turbulent diffusion. The model was implemented using an implicit numerical scheme with changing directions. A comparison between the model calculations and an analytical solution for the advection-diffusion equation shows good agreement. Relatively low numerical diffusion of the adopted advection scheme was noted. Results for the hilly region of central Israel are presented for a summer case. 相似文献
63.
S. A. Fedotov V. B. Enman Yu. P. Nikitenko M. A. Maguskin V. E. Levin S. V. Enman 《Bulletin of Volcanology》1980,43(1):35-45
The paper discusses the results of geodetic investigations performed in the region of the large 1975–1976 Tolbachik fissure eruption in Kamchatka. Using data from repeated triangulation and trigonometric levelings, horizontal and vertical displacements have been detected in an area of 3,500 km2. Two zones have been recognized: the tension and uplift zone that is probably due to magma intrusion from depths to the surface along the line of new cones and the extensive compensative subsidence zone located at a distance of 20–50 km from the nearest newly-formed cones. Measurements made with small distance measuring device showed the dynamics of feeding basalt dykes intrusion and made it possible to determine their width (a little greater than 1 m) and magma and gas overpressure (50–250 bar). Data have been obtained on dimensions and growth of cones and on vertical ground deformation in the area of new cones during and after the eruption. 相似文献
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F. Rohrer D. Brüning E. S. Grobler M. Weber D. H. Ehhalt R. Neubert W. Schüßler I. Levin 《Journal of Atmospheric Chemistry》1998,31(1-2):119-137
Ambient mixing ratios of NO, NO2, and O3 were determined together with the photolysis frequency of NO2, JNO2, at a rural, agricultural site in Germany. The data were collected during the POPCORN-campaign from August 1 to August 24, 1994, in a maize field 6 m above ground. The medians of the NO, NO2, and O3 mixing ratios between 10:00 and 14:00 UT were 0.25, 1.09, and 45 ppbv, respectively. The corresponding median of JNO2 was 6.0 · 10–3 s–1. NOx = NO + NO2 showed a strong diurnal variation with maximum mixing ratios at night, suggestive of a strong local surface source of NO, probably by microbial activity in the soil. The estimated average emission rate was 40 ng(N) m–2 s–1 of NOx, the major part of it probably in the form of NO. The available measurements allowed the estimation of the local NOx budget. At night the budget is almost closed and the measured NOx mixing ratios can be explained by the local source, local dry deposition of NO2, formation of NO3 and N2O5, and vertical exchange of air across the nocturnal inversion. During day-time, the local surface source of NO is not sufficient to explain the measured mixing ratios, and horizontal advection of NOx to the site must be included. The NO2/NO ratio during the morning und late afternoon is lower than predicted from the photostationary state owing to the local NO surface source, but is regulary higher during the hours around noon. For noon, August 10, 1994, the NO2/NO ratio was used to derive the momentary lower limit for the concentration of the peroxy-radicals of 2.2 · 109 cm–3 (86 pptv). 相似文献
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68.
Ocean Dynamics - Sea level rise (SLR) is causing acceleration in the frequency and duration of minor tidal flooding (often called “sunny-day” or “nuisance” flooding) along... 相似文献
69.
B. W. Levin E. V. Sasorova G. M. Steblov A. V. Domanskii A. S. Prytkov E. N. Tsyba 《Izvestiya Physics of the Solid Earth》2017,53(4):540-544
For more than a decade, the global network of GPS stations whose measurements are part of the International GPS Service (IGS) have been recording cyclic variations in the radius vector of the geodetic ellipsoid with a period of one year and amplitude of ~10 mm. The analysis of the figure of the Earth carried out by us shows that the observed variations in the vertical component of the Earth’s surface displacements can induce small changes in the flattening of the Earth’s figure which are, in turn, caused by the instability of the Earth’s rotation. The variations in the angular velocity and flattening of the Earth change the kinetic energy of the Earth’s rotation. The additional energy is ~1021 J. The emerging variations in the flattening of the Earth’s ellipsoid lead to changes in the surface area of the Earth’s figure, cause the development of deformations in rocks, accumulation of damage, activation of seismotectonic processes, and preparation of earthquakes. It is shown that earthquakes can be caused by the instability of the Earth’s rotation which induces pulsations in the shape of the Earth and leads to the development of alternating-sign deformations in the Earth’s solid shell. 相似文献
70.
Recent studies show that in addition to wind and air pressure effects, a significant portion of the variability of coastal sea level (CSL) along the US East Coast can be attributed to non-local factors such as variations in the Gulf Stream and the North Atlantic circulation; these variations can cause unpredictable coastal flooding. The Florida Current transport (FCT) measurement across the Florida Straits monitors those variations, and thus, the study evaluated the potential of using the FCT as an indicator for anomalously high water level along the coast. Hourly water level data from 12 tide gauge stations over 12 years are used to construct records of maximum daily water levels (MDWL) that are compared with the daily FCT data. An empirical mode decomposition (EMD) approach is used to divide the data into high-frequency modes (periods T < ~30 days), middle-frequency modes (~30 days < T < ~90 days), and low-frequency modes (~90 days < T < ~1 year). Two predictive measures are tested: FCT and FCT change (FCC). FCT is anti-correlated with MDWL in high-frequency modes but positively correlated with MDWL in low-frequency modes. FCC on the other hand is always anti-correlated with MDWL for all frequency bands, and the high water signal lags behind FCC for almost all stations, thus providing a potential predictive skill (i.e., whenever a weakening trend is detected in the FCT, anomalously high water is expected along the coast over the next few days). The MDWL-FCT correlation in the high-frequency modes is maximum in the lower Mid-Atlantic Bight, suggesting influence from the meandering Gulf Stream after it separates from the coast. However, the correlation in low-frequency modes is maximum in the South Atlantic Bight, suggesting impact from variations in the wind pattern over subtropical regions. The middle-frequency and low-frequency modes of the FCT seem to provide the best predictor for medium to large flooding events; it is estimated that ~10–25% of the sea level variability in those modes can be attributed to variations in the FCT. An example from Hurricane Joaquin (September–October, 2015) demonstrates how an offshore storm that never made landfall can cause a weakening of the FCT and unexpected high water level and flooding along the US East Coast. A regression-prediction model based on the MDWL-FCT correlation shows some skill in estimating high water levels during past storms; the water level prediction is more accurate for slow-moving and offshore storms than it is for fast-moving storms. The study can help to improve water level prediction since current storm surge models rely on local wind but may ignore remote forcing. 相似文献