902 resultados para 69-505


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This dataset includes basic information (location and depth) and major ion chemistry (Sodium, Chloride, Calcium, Nitrate) of snow cores from East Antarctic ice sheet. The snow cores were collected from two different regions - central Dronning Maud Land (cDML) and Princess Elizabeth Land (PEL) during the austral summer of 2008-09.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

River runoff is an essential climate variable as it is directly linked to the terrestrial water balance and controls a wide range of climatological and ecological processes. Despite its scientific and societal importance, there are to date no pan-European observation-based runoff estimates available. Here we employ a recently developed methodology to estimate monthly runoff rates on regular spatial grid in Europe. For this we first assemble an unprecedented collection of river flow observations, combining information from three distinct data bases. Observed monthly runoff rates are first tested for homogeneity and then related to gridded atmospheric variables (E-OBS version 12) using machine learning. The resulting statistical model is then used to estimate monthly runoff rates (December 1950 - December 2015) on a 0.5° x 0.5° grid. The performance of the newly derived runoff estimates is assessed in terms of cross validation. The paper closes with example applications, illustrating the potential of the new runoff estimates for climatological assessments and drought monitoring.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The cores and dredges described in this report were taken on the KH-69-2 Expedition in April-June, 1969 by the Ocean Research Institute, University of Tokyo from the Hakuho Maru. A total of 12 cores and dredges sites have been recovered.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recent revisions of the geological time scale by Kent and Gradstein (in press) suggest that, on the average, Cretaceous magnetic anomalies are approximately 10 m.y. older than in Larson and Hilde's (1975) previous time scale. These revised basement ages change estimates for the duration of alteration in the ocean crust, based on the difference between secondary-mineral isochron ages and magnetic isochron-crustal ages, from 3 to approximately 13 m.y. In addition to the revised time scale, Burke et al.'s (1982) new data on the temporal variation of 87Sr/86Sr in seawater allow a better understanding of the timing of alteration and more realistic determinations of water/rock ratios during seawater-basalt interaction. Carbonates from all DSDP sites which reached Layer 2 of Atlantic crust (Sites 105, 332, 417, and 418) are deposited within 10-15 m.y. of crustal formation from solutions with 87Sr/86Sr ratios identical to unaltered or contemporaneous seawater. Comparisons of the revised seawater curve with the 87Sr/86Sr of basement carbonates is consistent with a duration of approximately 10-15 m.y. for alteration in the ocean crust. Our preliminary Sr and 87Sr/86Sr data for carbonates from Hole 504B, on 5.9-m.y.-old crust south of the Costa Rica Rift, suggest that hydrous solutions from which carbonates precipitated contained substantial amounts of basaltic Sr. For this reason, carbonate 87Sr/86Sr cannot be used to estimate the duration of alteration at this site. A basalt-dominated alteration environment at Hole 504B is consistent with heat-flow evidence which indicates rapid sediment burial of crust at the Costa Rica Rift, sealing it from access by seawater and resulting in unusually low water/rock ratios during alteration.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ne, Ar, Kr, Xe, and K2O were measured in representative samples of holocrystalline basalt from DSDP Hole 504B. No hiatus in inert gas abundance is recognized at the base of the "oxic" alteration zone and the extent rather than the nature of alteration appears to determine these abundances. When the inert gas abundances are separately plotted against K2O, two distinct trends of loss emerge, one for alteration involving K-gain, the other for K-loss. Apparent whole-rock K-Ar ages are anomalous in the upper 50 m of basement, and below 300 m sub-basement. In the intervening zone of basement, celadonization adds sufficient potassium and eliminates enough "primary" 40Ar early in the history of the basalts for "excess" 40Ar to become subordinate to radiogenic 40Ar in basalts showing potassium enrichment greater than 0.2%. Stratigraphically correct K-Ar ages are obtained, therefore, from K-enriched basalts of the oxic alteration zone.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Online gambling is a popular activity among adolescents. However, there has been a notable increase in the number of young people who suffer or are on the verge of pathological gambling. We review the impact of online gambling on young people and discuss the desiderability of the concept of “gambling responsibly” in order to alert of their risks and effectively prevent access to minors. The main factors associated with pathological gambling are the age of start, the family environment, the infl uence of advertising, the consumption of stimulants, and the attitudes of the peer group. Both the government and the gaming industry itself should consider these factors and develop comprehensive plans that ensure a safe and controlled model game. In this context, advertising must take into account criteria of consumer protection knowing that even if they are not allowed, children can easily have access to online gambling. All agents involved, including public and social agents, must provide mechanisms for prevention and awareness of a problem that arouses little social consciousness and excessive carelessness.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

La dynastie des Flaviens est souvent mal connue et appréciée en raison de sa situation chronologique, « coincée » entre la famille des descendants de César et d’Auguste et celle allant de Trajan à Marc Aurèle. Elle passe parfois pour une simple dynastie de « transition » qui aurait uniquement servi de passerelle entre deux familles considérées comme plus brillantes qui ont par ailleurs laissé un souvenir plus durable. En un peu plus d’un quart de siècle (69-96), Vespasien, Titus et Domitien ont pourtant davantage fait pour la stabilité de Rome et de l’Empire que certains de leurs prédécesseurs ou successeurs. Sorti vainqueur des troubles civils de l’année des quatre empereurs (68-69), Vespasien ramena la paix en Orient et en Italie en plus de s’attacher à stabiliser les institutions et de reconstituer les finances de l’État, passablement écornées par les dernières années du Principat de Néron (54-68) et la guerre civile elle-même. Plus que la paix et la stabilité à l’intérieur et aux frontières de l’Empire, il fit cependant en sorte de refonder les bases institutionnelles du Principat en assumant sa transformation en un régime monarchique et héréditaire. Un principe parfaitement admis puisque ses deux fils adultes, Titus et Domitien, lui succédèrent sans difficulté. Davantage peut-être que les récits laissés par les sources littéraires anciennes, les inscriptions romaines et italiennes ainsi que les monnaies émises par l’atelier de Rome sont probablement le meilleur témoignage permettant de saisir le plus précisément et le plus profondément l’idée que les Flaviens se faisaient d’eux-mêmes et du pouvoir dont ils étaient investis. Le contenu de leur titulature officielle comme leurs choix iconographiques permettent ainsi de dégager leurs différents thèmes de propagande qui laissent finalement apparaitre une vraie continuité dans leur idéologie du pouvoir et leur manière de gouverner. Vespasien a ainsi posé des fondations idéologiques et politiques que ses fils ont globalement poursuivies et respectées, ce qui renforce l’idée selon laquelle les Flaviens ont effectivement suivi un « programme » qui les distinguait de leurs prédécesseurs et de leurs successeurs. Malgré des différences parfois importantes dans leurs pratiques, les inscriptions et l’iconographie monétaire permettent ainsi de mettre en lumière le fait que Titus et Domitien ont finalement moins cherché à faire preuve d’originalité qu’à s’inscrire dans la continuité de l’œuvre de leur père afin de garantir le maintien de la paix et avec elle la prospérité et la stabilité de l’État, et avec elles la satisfaction et la tranquillité de l’ensemble de la société.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A snapshot of water resource trends prepared by the Iowa DNR in collaboration with the Iowa Department of Agriculture and Land Stewardship, the U.S. Geological Survey, and The Iowa Homeland Security and Emergency Management Department.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fondo Margaritainés Restrepo