Climate in the Czech Lands during the 1780s in Light of the Daily Weather Records of Parson Karel Bernard Hein of Hodonice (Southwestern Moravia): Comparison of Documentary and Instrumental Data   总被引：1，自引：1，他引：0  

Rudolf Brázdil  Hubert Valášek  Jarmila Macková 《Climatic change》2003,60(3):297-327

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Velocity-Porosity Relationships: Predictive velocity model for cemented sands composed of multiple mineral phases.     

Mark A. Knackstedt  Christoph H. Arns  W. Val Pinczewski 《Geophysical Prospecting》2006,54(2):237-237

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The glacial inception as recorded in the NorthGRIP Greenland ice core: timing, structure and associated abrupt temperature changes     

Amaelle Landais  Valérie Masson-Delmotte  Jean Jouzel  Dominique Raynaud  Sigfus Johnsen  Christof Huber  Markus Leuenberger  Jakob Schwander  Bénédicte Minster 《Climate Dynamics》2006,26(2-3):273-284

The mechanisms involved in the glacial inception are still poorly constrained due to a lack of high resolution and cross-dated climate records at various locations. Using air isotopic measurements in the recently drilled NorthGRIP ice core, we show that no evidence exists for stratigraphic disturbance of the climate record of the last glacial inception (∼123–100 kyears BP) encompassing Dansgaard–Oeschger events (DO) 25, 24 and 23, even if we lack sufficient resolution to completely rule out disturbance over DO 25. We quantify the rapid surface temperature variability over DO 23 and 24 with associated warmings of 10±2.5 and 16±2.5°C, amplitudes which mimic those observed in full glacial conditions. We use records of δ¹⁸O of O₂ to propose a common timescale for the NorthGRIP and the Antarctic Vostok ice cores, with a maximum uncertainty of 2,500 years, and to examine the interhemispheric sequence of events over this period. After a synchronous North–South temperature decrease, the onset of rapid events is triggered in the North through DO 25. As for later events, DO 24 and 23 have a clear Antarctic counterpart which does not seem to be the case for the very first abrupt warming (DO 25). This information, when added to intermediate levels of CO₂ and to the absence of clear ice rafting associated with DO 25, highlights the uniqueness of this first event, while DO 24 and 23 appear similar to typical full glacial DO events.  相似文献   

Guest editorial     

Val R. Swail  Paula Etala  Shishir K. Dube  Kevin Horsburgh 《Natural Hazards》2009,51(1):1-2

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Development of a hydrodynamic model of the Bay of Biscay. Validation of hydrology     

Pascal Lazure  Valérie Garnier  Franck Dumas  Christelle Herry  Marina Chifflet 《Continental Shelf Research》2009,29(8):985-997

The hydrology of the Bay of Biscay was investigated using the regional ocean model MARS3D (Model for Application at Regional Scale). The simulated hydrology is compared to a set of various data encompassing monthly climatology, remote sensing SST, CTD casts, and coastal salinity measurements. Special focus was put on the validation over the continental shelf. This paper reports that despite some misfits, the climatological hydrology and its seasonal variability are correctly simulated. Various statistics computed over the period from 1999–2004 highlight different aspects of the hydrology. The biases and root mean square errors (RMSE) remain very weak at all depths when comparing salinity (<0.1 and <0.6 psu respectively). The predicted temperature shows a global overestimation of temperature (bias of around 0.8 °C) and the maximum errors are located near the thermocline (rmse of 1 °C at 20–40 m). The model is shown to properly reproduce the annual dynamics of sea surface temperature, as well as the dynamics of large river plumes observed by high frequency time series from coastal salinity gauges. The misfits highlighted by these various comparisons between model and observations are attributed to heat fluxes and mixing parameterisation.  相似文献   

The Marine Planning Framework for South Australia: A new ecosystem-based zoning policy for marine management     

Val Day  Rosemary PaxinosJon Emmett  Alison WrightMeg Goecker 《Marine Policy》2008

The Marine Planning Framework for South Australia is a new large-scale, ecosystem-based zoning policy for management of development and use in the marine environment. Utilising the Geographic Information System (GIS), the model establishes four ecologically rated zones, derived from known ecological criteria. A series of goals, objectives and strategies represent the desired outcomes for each of the ecologically rated zones. A Performance Assessment System (PAS) will subsequently evaluate the success of the marine plans. Implementation will be supported by a collaborative whole-of-government approach. Marine plans will facilitate the delivery of long-term protection to the marine environment as a whole ecosystem, whilst enabling a broad range of activities to occur in a sustainable manner.  相似文献   

Magnetic fields in methanol maser condensations based on data for related regions. Seven sources: Astrophysical parameters     

O. S. Bayandina  A. V. Alakoz  I. E. Val’tts 《Astronomy Reports》2014,58(7):462-470

The astrophysical parameters of seven OH maser condensations are estimated based on magnetic fields obtained from polarization observations carried out on the Nan cay Radio Telescope (France) in the 1665 and 1667 MHz lines in four Stokes parameters. Regions in the studied sources containing the observed clusters of maser condensations, as well as clusters of Class I and II methanol masers, have been identified. The associations of the masers are real; i.e., the magnetic field in the clusters can also extend to groups of methanol masers. The linear dimensions of these associations have been found. The ratio of the mass to the magnetic flux, ratio of the thermal to the magnetic pressure, and virial relationships between energies (kinetic, magnetic, and gravitational) in the regions containing the OH andmethanol masers have been obtained. In sources whose magnetic fields have been determined fairly reliably, the ratio of the mass to the magnetic flux exceeds a critical value, and the energies of chaotic motions and of the magnetic field are considerably smaller than the gravitational binding energy. On the other hand, in all cases, the ratio of the thermal to the magnetic pressure is <1, suggesting that the clouds may be in amagnetically dominated regime. This inconsistency is related to probable uncertainties in the the magnetic field values and the estimated distances to the sources, which may lead to overestimation of the sizes of the regions studied.  相似文献   

Calcium,Na, K and Mg Concentrations in Seawater by Inductively Coupled Plasma‐Atomic Emission Spectrometry: Applications to IAPSO Seawater Reference Material,Hydrothermal Fluids and Synthetic Seawater Solutions     

Philippe Besson  Jefferson Degboe  Benjamin Berge  Valérie Chavagnac  Sébastien Fabre  Gilles Berger 《Geostandards and Geoanalytical Research》2014,38(3):355-362

We report a measurement procedure to determine simultaneously the major cation concentrations (Na, Ca, K and Mg) of seawater‐derived solutions by inductively coupled plasma‐atomic emission spectrometry. The best results were obtained when the IAPSO (‘standard’) seawater reference material was diluted by thirty times with Milli‐Q^® water. We obtained an average reference value r_K (the ratio of the mass fraction of potassium to that of chlorine, i.e., (g kg^?1)/(g kg^?1)) for IAPSO seawater of 0.0205 ± 0.0006 (2.9% RSD), not significantly different from 0.0206 ± 0.0005 (2.4% RSD) for seawater composition reported in the literature. The measured Na, Ca and Mg concentrations correspond to r_Na, r_Ca and r_Mg values of 0.5406 ± 0.0026 (0.5% RSD), 0.02192 ± 0.00048 (2.2% RSD) and 0.06830 ± 0.00047 (0.7% RSD), respectively, in line with previous values measured by wet‐chemistry and atomic absorption spectrophotometry or wet‐chemical titration. Our measurement procedure was used successfully on synthetic seawater solutions and high‐temperature hydrothermal fluids.  相似文献   

Contribution of climatic and anthropogenic effects to the hydric deficit of peatlands     

Chrystelle Auterives  Luc Aquilina  Olivier Bour  Mélanie Davranche  Valérie Paquereau 《水文研究》2011,25(18):2890-2906

The present study makes use of a detailed water balance to investigate the hydrological status of a peatland with a basal clay‐rich layer overlying an aquifer exploited for drinking water. The aim is to determine the influence of climate and groundwater extraction on the water balance and water levels in the peatland. During the two‐year period of monitoring, the hydrological functioning of the wetland showed a hydric deficit, associated with a permanent unsaturated layer and a deep water table. At the same time, a stream was observed serving as a recharge inflow instead of draining the peatland, as usually described in natural systems. Such conditions are not favourable for peat accumulation. Field investigations show that the clay layer has a high hydraulic conductivity (from 1·10^?7 to 3·10^?9 m.s^?1) and does not form a hydraulic barrier. Moreover, the vertical hydraulic gradients are downward between the peat and the sand aquifer, leading to high flows of groundwater through the clay layer (20–48% of the precipitation). The observed hydric deficit of the peatland results from a combination of dry climatic conditions during the study period and groundwater extraction. The climatic effect is mainly expressed through drying out of the peatland, while the anthropogenic effect leads to an enhancement of the climatic effect on a global scale, and a modification of fluxes at a local scale. The drying out of the peatland can lead to its mineralisation, which thus gives rise to environmental impacts. The protection of such wetlands in the context of climate change should take account of anthropogenic pressures by considering the wetland‐aquifer interaction. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Storm waves in Canadian waters: A major marine hazard     

Madhav L. Khandekar  Val R. Swail 《大气与海洋》2013,51(2):329-357

Abstract

In this paper, an overview of storm waves associated with intense weather systems affecting the east and west coasts of Canada is presented. The paper presents the wave climatology of the east and west coasts in terms of the 100‐year significant and maximum wave heights and further analyses the directional distribution of wave heights at selected locations in the Canadian east and west coasts offshore. The paper also analyses wave hazards associated with storm waves in the Beaufort Sea as well as the Canadian Great Lakes region. A section on ocean wave modelling provides a brief history of the development of ocean surface wave models and its present status. The paper further considers the impact of climate change scenarios on wave hazards and finally examines mitigation measures in terms of wave products available from operational wave models and related wave climatology.  相似文献