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851.
The relationship between the intensity of surface wind waves and near-water wind is analyzed. The data of measuring wind waves and near-water wind under natural conditions in the Black Sea (July 2004) and Norwegian Sea (June 2003, 16th cruise of the R/V Akademik Sergei Vavilov) are used. A phenomenon of negative correlations has been found between the intensity of wind waves and near-water wind in regions of substantial restructuring of wind waves in the field of inhomogeneous flows: wind-wave amplification during wind decay and vice versa. Examples of such observations are presented, a theoretical model is constructed for the observed phenomenon, and a good agreement is obtained between theory and experiment.  相似文献   
852.
We present the results of microwave observations of the ozone content variability in the upper stratosphere and lower mesosphere during a total solar eclipse of March 29, 2006 at the Kislovodsk high-altitude scientific station. An increase in the concentration of mesospheric ozone was recorded during the eclipse. At a height of 60 km, the ozone concentration increased by 40%, which is close to the value of diurnal ozone variations.  相似文献   
853.
The leading modes of interannual and long-term variations in the stratospheric and tropospheric circulation and total ozone (TOMS data) and their relations to Northern Hemisphere sea surface temperature (SST) anomalies are investigated using the monthly mean NCEP/NCAR reanalysis data for the winter months of 1958–2003. Strong correlations are indicated between the interannual total ozone variations over Labrador and the North Atlantic and changes in the stratospheric polar vortex. The onset of major stratospheric warmings is connected not only with the strengthening of westerlies at the 500-hPa level in the midlatitude Atlantic, but also with the weakening of tropospheric winds over the north of eastern Siberia and strengthening over the Far East. In years with major stratospheric warmings, abnormally cold winters are observed in Eurasia, especially in eastern Siberia and northeastern China. The calculated simultaneous (with no time lags) correlations of the stratospheric circulation changes with El Niño/La Niña events give evidence of low correlations between the tropical Pacific SST anomalies and the stratospheric dynamics in the Arctic. However, there are high correlations of the extratropical Pacific and Atlantic SST anomalies with interannual tropospheric and stratospheric circulation variations, the stratospheric dynamics being more strongly connected with Pacific SST than with Atlantic SST anomalies. The interannual changes in tropospheric circulation are coupled to SST anomalies in both the Pacific and the Atlantic. Mechanisms of long-term changes in the interactive ocean-atmosphere-ozone layer system are discussed.  相似文献   
854.
From long-term observations of ozone evolution in the stratosphere of the Kola Peninsula in the 2002/2003 winter, the rates of chemical destruction of ozone and its net loss at isentropic levels of 530 K (an altitude of about 22 km) and 465 K (an altitude of about 19 km) ar evaluated with consideration for diabatic descent of air masses. These rates were ?18.6±3.3 and ?14.3±2.9 ppb/day and the net loss of ozone due to its chemical destruction over the period from December 1, 2002, to March 5, 2003, reached 1.77±0.33 ppm and 1.36±0.29 ppm, respectively. At the lower level, these data are in satisfactory agreement (to within measurement errors) with other measurements that were taken at that time. At a potential-temperature level of 530 K, the ozone loss in the 2002/2003 season evaluated from our data and from similar microwave measurements performed in Kiruna (Sweden) virtually coincides and testifies to the fact that the net loss increases with altitude. These inferences are inconsistent with the results obtained with the Match technique and the method of averaging over a vortex, which indicate that the ozone loss decreases with altitude. However, since polar stratospheric clouds were detected regularly in December and early January at levels up to 600 K or higher, it may be suggested that the ozone loss at these altitudes can be comparable to the values found for isentropic levels of 465 to 475 K.  相似文献   
855.
Similar to other high-latitude ocean basins, the subarctic Pacific exhibits strong seasonal and inter-annual variations in the abiotic factors of the environment, which, in turn, strongly influence biological objects. One of the principal factors of this kind is the temperature regime. For our research, we chose pink salmon because more than 90% of its natural mortality occurs precisely during the wintering period. The lifetime of pink salmon is only one year, and the conditions of their populations reflect the thermal regime of the given year. The main wintering area of Asian pink salmon is the part of the subarctic frontal zone located south of the Aleutian Islands (43°–46°N). This region features sufficiently high wintertime concentrations of chlorophyll a and temperature conditions favorable for pink salmon wintering. The interannual temperature variability in the frontal zone is close to zero, and the width of the frontal zone may significantly change depending on the winter severity. In “milder” winters, the area of wintering extends, while, in “severe” winters, it is rather narrow, the forage base for fish decreases, they become more accessible for predators, and their survival rates sharply drop.  相似文献   
856.
857.
An experiment on the correction of underwater images distorted by waves at the air-water interface was conducted using a laboratory modeling installation intended for experimental examination of light and image transfer across a water surface covered with waves. A digital color camera was used for the simultaneous formation of the image of the underwater test object through the disturbed surface and of the superimposed glitter pattern. Both images are spectrally separated. Processing the glitter pattern makes it possible to obtain the values of the surface slopes at a limited number of points and to use these slopes for retrieval of image fragments. The total corrected image is formed by integration of about 300 partially corrected fragments. This image is close to that obtained through a wave-free water surface.  相似文献   
858.
大洋富钴结壳和锰结核一样是潜在的海底矿产资源,对其成因的研究将有助于指导找矿和资源评价。通过大型反光显微镜、透射电子显微镜和其他测试手段,系统研究了结壳的结构构造、物质组成以及叠层石纹层与超微生物的关系。发现结壳与光滑型锰结核的叠层石类型及超微生物种极其相似,它们都以微小叠层石和中华微放线菌为主要特征,具有相同的生物成因机制。认为超微生物建构的锰质叠层石柱体是大洋富钴结壳的基本框架,从而对结壳矿体的形成提出了新的见解。  相似文献   
859.
Four cruises were conducted during 2002--2003 in the Changjiang Estuary and adjacent coastal areas. The data presented show a clear coast to open sea gradient in nutrients related to the river inputs. Maximum values of chlorophyll a were typically observed at intermediate salinities at surface water and coincided with non-conservative decreases in nutrients along the salinity gradient, indicating that removal of nutrients was related to phytoplankton uptake. The seasonal variations of nutrient concentrations were just opposite to those of chlorophyll a, indicating that the seasonal variations of nutrients were mainly controlled by phytoplankton uptake, whereas riverine inputs merely weakened or balanced its extent. During the estuarine mixing, phosphate demonstrated some remobilization during all the four cruises; whereas both conservative and non-conservative behaviors for dissolved inorganic nitrogen and silicate were observed in the study area, indicating that both biotic and abiotic events may affect their behaviors during the estuarine mixing. Under the influence of freshwater inputs with high value of ratio of nitrogen to phosphorus, the estuarine and coastal waters impacted by the Changjiang plume were high ( 〉 30) in ratio of nitrogen to phosphorus, but rates of primary production were apparently not constrained by any kind of nutrient elements. However, the low ( 〈 1 ) ratio of silicate to nitrogen in most of the study area might be linked with the rapidly increasing frequency of harmful algal bloom (HAB) incidents in recent years in the coastal waters impacted by the Changjiang plume.  相似文献   
860.
Using seismic and Chirp sonar profiles, this paper tests the hypothesis that hyperpycnal flows are the main factor controlling the formation and maintenance of the meandering Kaoping submarine canyon off SW Taiwan. Cross-section geometries, and erosional as well as depositional features vary along the canyon course. In the proximal, sinuous part of the canyon, down-cutting into the shelf strata has created a relief of 340 m. The cause of this intense erosion of the seafloor is suggested to be the frequent development of hyperpycnal flows. A seismic section across a meander in the distal part of the canyon shows levees formed by overspilled sediments at the outer bend, and a terrace characterized by relatively flat stratified facies at the inner bend. The geological setting and climatic conditions in SW Taiwan (e.g. earthquakes, typhoons, floods), as well as major river–canyon connections (for example, direct input of highly concentrated suspended sediment) would all promote hyperpycnal flow generation. This causes axial incision, canyon wall slumping, and the formation of levees by spill-over deposition in the upper reach of the Kaoping Canyon.  相似文献   
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