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61.
Natural Hazards - Large-scale wildfires and windstorms are the most important disturbance agents for the Russian boreal forests. The paper presents an assessment of fire-related and wind-induced...  相似文献   
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This paper examines the role of atmospheric forcing in modifying the pathways of riverine water on the Laptev Sea shelf, using summer-to-winter hydrographic surveys from 2007 to 2009. Over the two consecutive winter seasons of 2007–2008 and 2008–2009 in the area of the winter coastal polynya, our data clearly link winter surface salinity fields to the previous summer conditions, with substantially different winter salinity patterns preconditioned by summer atmospheric forcing. In the summer of 2007, dominant along-shore westerly winds in the cyclonic regime force the Lena River runoff to flow eastward. In contrast, in the summer of 2008, dominant along-shore easterly winds over the East Siberian Sea and on-shore northerly winds over the Laptev Sea in the anticyclonic regime lock the riverine water in the vicinity of the Lena Delta. Over the coastal polynya area in the southeastern Laptev Sea these patterns precondition a surface salinity difference of 8–16 psu between the winters of 2008 and 2009. Overall, this indicates a residence time of at least half a year for riverine water on the Laptev Sea shelf. Future climate change associated with an enhanced summer cyclonicity over the eastern Arctic may turn more riverine water eastward along the eastern Siberian coast, resulting in weaker vertical density stratification over the Laptev Sea shelf, with possible impact on the efficiency of vertical mixing and polynya dense water production.  相似文献   
64.
Mineralogy and Petrology - The crystal structure of batisite, Na2BaTi2 (Si4O12)O2, from the Inagli massif (Aldan, Yakutia, Russia) was refined to R 1 = 0.032 for 1449 unique...  相似文献   
65.
FESOM under coordinated ocean-ice reference experiment forcing   总被引:1,自引:1,他引:0  
Characteristics of the ocean state simulated with the Finite-Element Sea-Ice Ocean Model (FESOM) under the normalized year forcing of Coordinated Ocean-ice Reference Experiments (COREs; Griffies et al., Ocean Model 26:1–46, 2009) are compared with those of other models participating in COREs. In contrast to these models, FESOM is run on an unstructured mesh (with resolution varying between 20 and 150 km). It is shown that the ocean state simulated by FESOM is in most cases within the spread of other models, demonstrating that the unstructured mesh technology has reached the stage when it becomes a reliable tool for studying the large-scale ocean general circulation.  相似文献   
66.
The crystal structure of ilinskite, NaCu5O2(SeO3)2Cl3, a rare copper selenite chloride from volcanic fumaroles of the Great fissure Tolbachik eruption (Kamchatka peninsula, Russia), has been solved by direct methods and refined to R 1?=?0.044 on the basis of 2720 unique observed reflections. The mineral is orthorhombic, Pnma, a?=?17.769(7), b?=?6.448(3), c?=?10.522(4) Å, V?=?1205.6(8) Å3, Z?=?4. The The CuOmCln coordination polyhedra share edges to form tetramers that have 'additional' O1 and O2 atoms as centers. The O1Cu4 and O2Cu4 tetrahedra share common Cu atoms to form [O2Cu5]6+ sheets. The SeO3 groups and Cl atoms are adjacent to the [O2Cu5]6+ sheets to form complex layers parallel to (100). The Na+ cations are located in between the layers. A review of mixed-ligand CuOmCln coordination polyhedra in minerals and inorganic compounds is given. There are in total 26 stereochemically different mixed-ligand Cu-O-Cl coordinations.  相似文献   
67.
The high quality inventory is an important step to greenhouse gas emission mitigation. The inventory quality is estimated by means of the uncertainty analysis. The level of uncertainty depends upon the reliability of activity data and the parameters used. An attempt has been made to improve the accuracy of the estimates through a shift from production-based method (IPCC Tier 1) (IPCC 2000) to enhanced combination of production-based and mass balance methods (IPCC Tier 2) (IPCC 2006) in the estimation of emissions from operations with oil that are key in the national greenhouse gas inventory of the Russian Federation. The IPCC Tier 2 (IPCC 2006) was adapted for the national conditions. The greenhouse gas emissions were calculated for 1990 to 2009 with the use of both methods. The quantitative uncertainty assessment of the calculations was performed, and the outcomes were compared. The comparison showed that the estimates made with the use of higher tier method resulted in higher accuracy and lower uncertainties (26 % respectively compared to previously derived 54 %).  相似文献   
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69.
We investigated the feasibility of the ensemble Kalman filter (EnKF) to reproduce oceanic conditions south of Japan. We have adopted the local ensemble transformation Kalman filter algorithm based on 20 members’ ensemble simulations of the parallelized Princeton Ocean Model (the Stony Brook Parallel Ocean Model) with horizontal resolution of 1/36°. By assimilating satellite sea surface height anomaly, satellite sea surface temperature, and in situ temperature and salinity profiles, we reproduced the Kuroshio variation south of Japan for the period from 8 to 28 February 2010. EnKF successfully reproduced the Kuroshio path positions and the water mass property of the Kuroshio waters as observed. It also detected the variation of the steep thermohaline front in the Kii Channel due to the intrusion of the Kuroshio water based on the observation, suggesting efficiency of EnKF for detection of open and coastal seas interactions with highly complicated spatiotemporal variability.  相似文献   
70.
We characterized the compositions of organic compounds in a Cheremushka bog sediment core (deposited over the last 35 kyr), located at the eastern coast of Lake Baikal, to obtain basic information about the terrestrial organic matter (OM) which contributed to Lake Baikal sediments. The bog sediment was analyzed for the molecular composition of n-alkanes, lignin phenols and n-C24 to C30 alkanoic acids, as well as the carbon isotopic composition of plant wax derived n-C27 to C33 alkanes.Concentrations of lignin phenols [vanillyl (V) plus syringyl (S) phenols] normalized to total organic carbon (TOC) in the Holocene are twice those for the last glacial maximum (LGM), while concentrations of TOC-normalized n-C24 to C30 alkanoic acids do not change markedly in this period. Thus, the ratio of lignin phenols to n-C24 to C30 alkanoic acids increases from the LGM to the Holocene. This result is essentially consistent with pollen analysis indicating an expansion of woody plants in the Holocene and a prevailing herb-abundant environment for the LGM. The δ13C values of n-C27 to C33 alkanes (e.g. ?29‰ to ?33‰ for C31) indicate the presence of C3-dominant plants throughout the core.The contribution of terrestrial OM to Lake Baikal sediments was estimated using the biomarkers, on the assumption that the OM in the bog sediments is a representative of the terrestrial OM around the lake. Hence, the estimation using lignin phenol or n-C24 to C30 alkanoic acid parameters indicates that 11–24% of the TOC in the Academician Ridge sediments is land-derived for both the Holocene and the LGM, which is similar to the estimates from C/N values of bulk OM. However, the estimates for terrestrial OM using the n-C27 to C33 alkane parameter are generally higher than those using lignin phenol or n-C24 to C30 alkanoic acid parameters. The difference is thought to be associated with the difference in source and behavior of these biomarkers.  相似文献   
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