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Ferenc?ácsEmail authorView author&#;s OrcID profile Dominika?Takács Hajnalka?Breuer Nóra?Skarbit 《Theoretical and Applied Climatology》2018,131(3-4):899-926
We present a 1-km2 gridded German dataset of hourly surface climate variables covering the period 1995 to 2012. The dataset comprises 12 variables including temperature, dew point, cloud cover, wind speed and direction, global and direct shortwave radiation, down- and up-welling longwave radiation, sea level pressure, relative humidity and vapour pressure. This dataset was constructed statistically from station data, satellite observations and model data. It is outstanding in terms of spatial and temporal resolution and in the number of climate variables. For each variable, we employed the most suitable gridding method and combined the best of several information sources, including station records, satellite-derived data and data from a regional climate model. A module to estimate urban heat island intensity was integrated for air and dew point temperature. Owing to the low density of available synop stations, the gridded dataset does not capture all variations that may occur at a resolution of 1 km2. This applies to areas of complex terrain (all the variables), and in particular to wind speed and the radiation parameters. To achieve maximum precision, we used all observational information when it was available. This, however, leads to inhomogeneities in station network density and affects the long-term consistency of the dataset. A first climate analysis for Germany was conducted. The Rhine River Valley, for example, exhibited more than 100 summer days in 2003, whereas in 1996, the number was low everywhere in Germany. The dataset is useful for applications in various climate-related studies, hazard management and for solar or wind energy applications and it is available via doi: 10.5676/DWD_CDC/TRY_Basis_v001. 相似文献
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Within the confines of Earth Observation Scientific Knowledge and Technology Transfer in Hungary (EKAT) titled ESA PECS project we gained forum for utilization of our earth observation (EO) knowledge and possibility for further development of experiences. The project aims the horizontal preparation of Hungary for ESA membership – for a dynamically developing sphere in the common part of science, technology and business. For the efficient transfer and dissemination, we preconceived target groups and principles to reach main take-up points and to open new forums of information exchange. Nowadays, user-friendly service, complex supply and real-validation process all have great importance. Joining units of suitable data choice, entire ingestion–processing chains and ergonomic interfaces can only offer a timely and professional solution for the challenges of industry and business sectors. It has to be clearly seen, that information and communication technologies (ICT) and information control becomes a more and more significant part of EO services. 相似文献
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Byoung‐Young Choi Seong‐Taek Yun Bernhard Mayer Gi‐Tak Chae Kyoung‐Ho Kim Kangjoo Kim Yong‐Kwon Koh 《水文研究》2010,24(3):317-330
We evaluated sources and pathways of groundwater recharge for a heterogeneous alluvial aquifer beneath an agricultural field, based on multi‐level monitoring of hydrochemistry and environmental isotopes of a riverside groundwater system at Buyeo, Korea. Two distinct groundwater zones were identified with depth: (1) a shallow oxic groundwater zone, characterized by elevated concentrations of NO3? and (2) a deeper (>10–14 m from the ground surface) sub‐oxic groundwater zone with high concentrations of dissolved Fe, silica, and HCO3?, but little nitrate. The change of redox zones occurred at a depth where the aquifer sediments change from an upper sandy stratum to a silty stratum with mud caps. The δ18O and δ2H values of groundwater were also different between the two zones. Hydrochemical and δ18O? δ2H data of oxic groundwater are similar to those of soil water. This illustrates that recharge of oxic groundwater mainly occurs through direct infiltration of rain and irrigation water in the sandy soil area where vegetable cropping with abundant fertilizer use is predominant. Oxic groundwater is therefore severely contaminated by agrochemical pollutants such as nitrate. In contrast, deeper sub‐oxic groundwater contains only small amounts of dissolved oxygen (DO) and NO3?. The 3H contents and elevated silica concentrations in sub‐oxic groundwater indicate a somewhat longer mean residence time of groundwater within this part of the aquifer. Sub‐oxic groundwater was also characterized by higher δ18O and δ2H values and lower d‐excess values, indicating significant evaporation during recharge. We suggest that recharge of sub‐oxic groundwater occurs in the areas of paddy rice fields where standing irrigation and rain water are affected by strong evaporation, and that reducing conditions develop during subsequent sub‐surface infiltration. This study illustrates the existence of two groundwater bodies with different recharge processes within an alluvial aquifer. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Seiji Maruyama Masaki Watanabe Tak Kunihiro Eizo Nakamura 《Geochimica et cosmochimica acta》2009,73(3):778-793
Elemental and isotopic abundances of lithium in chondrule constituents in the Allende CV3 meteorite were determined using secondary ion mass spectrometry. Olivines and mesostasis dominated by a feldspathic phase are depleted in Li ( and , respectively). In contrast, low-Ca pyroxenes and mesostasis dominated by a Na-rich phase are enriched in Li ( and , respectively) and the interchondrule matrix is generally enriched in Li ( on average). The Li isotopic abundance of olivine ranges from to 21. The spatial distributions of elemental and isotopic abundances of Li in olivines within individual chondrules exhibit no systematic pattern. This suggests that the distribution of Li in olivine was not disturbed during aqueous alteration or thermal metamorphism on the Allende meteorite parent body. Although mesostasis is the last crystallizing phase from a chondrule melt and is expected to be enriched in Li, in the Allende meteorite it is generally depleted in Li. We suggest that during aqueous alteration on the CV asteroid, Li in mesostasis was leached out by aqueous fluids. The Li-enriched Na-rich mesostasis was probably produced later by infiltration of Na-rich fluids. It seems likely that aqueous fluids sequestered alkali elements from the Allende-chondrite region in the CV parent asteroid, although significant amounts of Li are preserved in ferrous olivine in the interchondrule matrix. 相似文献
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A transect of the St Marys River estuary from above the point of maximum salt wedge penetration to coastal salinities was
conducted in July 1999. None of the parameters examined—dissolved organic carbon (DOC) content, UV light absorbance at 254
nm, and Total Luminescence spectra—follow the rule of conservative mixing. The characteristics of the different molecular
size fractions of the St Marys River natural organic matter (NOM), as well as the results of a laboratory mixing experiment,
provided evidence that loss of larger molecular size compounds from riverine NOM may occur by coagulation at salinities up
to 10. An apparent gain of carbon in the lower estuary was attributed to exports from abundant coastal marshes in this area.
The Total Luminescence spectra of the riverine NOM can be described by two peaks, centered respectively around 340/445 nm,
and 230/430 nm Excitation/Emission Wavelength Pair (EEWP), which are characteristic of humic materials of aquatic origin.
The samples from the high salinity stations exhibit peaks at lower emission wavelength EEWP 320/424 nm, which can be considered
as marine humic-like material. The presence of amino acid-tryptophan like peaks were observed, with EEWP 300/350 nm in some
of the high salinity samples. This peak was of high relative fluorescence intensity. It is hypothesized that the intense biological
activity of the salt marsh and near coastal area is responsible for the carbon addition as well as the appearance of the highly
fluorescence amino acid-protein like material. 相似文献
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Yusuke Yachi Hiroshi Kitagawa Tak Kunihiro Eizo Nakamura 《Geostandards and Geoanalytical Research》2014,38(1):95-102
Software designed for analytical laboratories to guarantee traceability and accessibility of rocks with their geochemical properties has been developed. The software documents the sample origin, current sample location and the location of any sample subsets (e.g., thin sections, solutions, etc.), and archives all associated geochemical data sets. The software can be installed on a personal computer so is available for use in any laboratory and allows curation before and after publication. The software will be of use in integrating and sharing geological reference materials within and among institutes. In this article, the system design and implementation are detailed. All source codes for the software are available at http://dream.misasa.okayama-u.ac.jp/ . 相似文献
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Chang Hwan Kim Chan Hong Park Eui Young Jeong Jong Sun Hwang Young Tak Ko 《Geo-Marine Letters》2009,29(3):161-169
In the Ulleung Basin, East Sea, the Dok Do seamount group comprises Dok Do (Dok Island), consisting of very small islets/rocks
and a large submerged volcanic edifice, and two voluminous tablemounts, Simheungtaek and Isabu. We attempted to reconstruct
the evolution of these seamounts, using virtual geomagnetic poles (VGPs) determined by the least-squares and the seminorm
magnetization methods, with 1,500 m upward continued magnetic anomalies. The VGPs of Dok Do with normal dipole anomaly, and
of Simheungtaek with normal dipole anomaly are located near the present magnetic pole. The VGP of Isabu with normal dipole
anomaly is located at low latitude, presumably due to overprints of reversals in the Tertiary, and the distortion of magnetization
and structures associated with volcanism after its formation. In contrast to the tablemounts, magnetic anomalies over Dok
Do are a combination of both normal polarity and reversed polarity dipoles in the northern hemisphere, indicating that Dok
Do has had at least two major eruptions, one during normal and another during reversed polarity intervals. From these results,
and information on the ages of the seamounts (either published radiometric ages of subaerial volcanic rocks, or ages reconstructed
in terms of reported elastic thickness incorporated into an existing cooling plate model), we tentatively propose that (1)
Isabu formed first, during a normal polarity interval after the opening of the East Sea had ceased; (2) this was followed
by an initial and subsequent large eruption of Dok Do during a normal polarity and a reversed polarity interval after about
5 Ma; and (3) the formation of Simheungtaek occurred in between that of Isabu and Dok Do in a normal polarity interval. The
pattern of normal/reversed magnetization is not inconsistent with the geomagnetic polarity timescale for at least the last
5 Ma. Nevertheless, precise ages of formation would need verification by additional geophysical/geochemical constraints. Evaluating
various possible models explaining the successive formation of the Dok Do seamounts, we currently favor fracturing and volcanism
related to compression-induced weakening of the extensional field from the late Miocene to Pliocene after the opening of the
East Sea. 相似文献
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Due to high density of vessel traffic, busy waterways are water areas with high potential for collisions. The application of AIS makes it possible to investigate accurate and actual behavior of collision-involved ships, and benefits vessel traffic management and waterways design for these areas. As a case study, the authors focus on a Traffic Separation Scheme (TSS) off Rotterdam Port in Europe, and using AIS data, statistical analysis is made for collision involved ships. In order to identify the correlation of CPA, which is a key indicator for collision avoidance, with ship's size, speed, and course, linear regression models are developed. To assess risks, a dynamic method based on SAMSON is presented. 相似文献