Protracted Recharge of Treated Sewage into Sand Part I—Quality Changes in Vertical Transport Through the Sand     

Donald B. Aulenbach  Ph.D.    Thomas P. Glavin  Jairo A. Romero Rojas 《Ground water》1974,12(3):161-169

  相似文献   

A numerical study of the transport and diffusion of coastal pollutants during the breeze cycle in the Island of Mallorca     

R. Romero  C. Ramis 《Annales Geophysicae》1996,14(3):351-363

An Eulerian study of the distribution over the Island of Mallorca of a non-reactive pollutant (SO₂) emitted from an electric power plant operating at present on the north coast is performed using a meso- numerical model, paying particular attention to the diffusive physical mechanisms. The study is applied to the conditions of sea-land breeze development. This is a local circulation that dominates the flow during the summer and favours transporting pollutants from the coast toward the centre of the island. Results indicate that values of the ground-level concentration higher than 5 g/m³ are restricted over a limited and mountainous region during the whole diurnal cycle. However, when the simulation is carried out with the inclusion of a twin electric plant which may be built on the south coast, the affected area becomes larger, especially early in the morning, when air over the island is sinking as a consequence of the land breeze development. The inclusion of dry deposition in the simulations does not produce important changes in the spatial and temporal evolution of the ground-level concentration.  相似文献   

Book review     

Katharine Kadinsky-Cade  Edo Nyland  Philip England  Marek Lewandowski  Kacper R. Rybicki  Maria Jelenska  Ursula B. Marvin  Earle R. Williams  David S. Gutzler 《Pure and Applied Geophysics》1989,130(4):751-779

  相似文献   

Forecasting annual precipitation to improve the operation of dams in the Comahue region,Argentina     

Paula Elisa Romero  Alfredo Luis Rolla  Fernando Losano 《水文科学杂志》2020,65(11):1974-1983

ABSTRACT

This paper attempts to design statistical models to forecast annual precipitation in the Neuquen and Limay river basins in the Comahue region of Argentina. These forecasts are especially useful as they are used to better organize the operation of hydro-electric dams, the agriculture in irrigated valleys and the safety of the population. In this work, multiple linear regression statistical models are built to forecast mean annual rainfall over the two river basins. Since the maximum precipitation occurs in the winter (June–August), forecasting models have been developed for the beginning of March and for the beginning of June, just before the rainy season starts. The results show that the sea-surface temperatures of the Indian and Pacific oceans are good predictors for March models and explain 42.8% of the precipitation index variance. The efficiency of the models increases in June, adding more predictors related to the autumn circulation.  相似文献   

Identifying Variable γ-ray Sources Through Radio Observations     

Josep M. Paredes  J. Martí  D. F. Torres  G. E. Romero  J. A. Combi  V. Bosch-Ramon  J. García-Sáanchez 《Astrophysics and Space Science》2005,297(1-4):223-233

We present preliminary results of a campaign undertaken with different radio interferometers to observe a sample of the most variable unidentified EGRET sources. We expect to detect which of the possible counterparts of the γ-ray sources (any of the radio emitters in the field) varies in time with similar timescales as the γ-ray variation. If the γ-rays are produced in a jet-like source, as we have modelled theoretically, synchrotron emission is also expected at radio wavelengths. Such radio emission should appear variable in time and correlated with the γ-ray variability.  相似文献   

Badland dynamics in the Central Pyrenees: temporal and spatial patterns of weathering processes     

E. Nadal‐Romero  D. Regüés  C. Martí‐Bono  P. Serrano‐Muela 《地球表面变化过程与地形》2007,32(6):888-904

  相似文献   

Paleoproductivity evolution off central Chile from the Last Glacial Maximum to the Early Holocene   总被引：1，自引：0，他引：1  

Oscar E. Romero  Jung-Hyn Kim  Dierk Hebbeln 《Quaternary Research》2006,65(3):519-525

A geochemical and paleontological reconstruction of paleoproductivity, upwelling intensity and sea surface temperature (SST) off central Chile at 35°S (GeoB3359-3) reveals marked changes from the Last Glacial Maximum (LGM) through the Early Holocene. Surface-water productivity was determined by the interaction between the atmospheric (the Southern Westerlies) and oceanographic (the Antarctic Circumpolar Current, ACC) systems from the LGM through early Termination I (TI). The northward shift of the climate zones during the LGM brought the ACC, as the main macronutrient source, closer to the GeoB3359-3, SST lowered, and surface water productivity and accumulation rates of biogenic components enhanced. With the poleward return of the Southern Westerlies and the ACC, the subtropical high-pressure system became the dominant atmospheric component southward till 35°S during the late TI and Early Holocene and caused surface water productivity to increase through enhanced upwelling.  相似文献   

A relation between extreme daily precipitation and extreme short term precipitation   总被引：1，自引：0，他引：1  

Yanina L. Romero  J. Bessembinder  N. C. van de Giesen  F. H. M. van de Ven 《Climatic change》2011,106(3):393-405

The Royal Netherlands Meteorological Institute (KNMI) has published the KNMI’06 climate scenarios in 2006. These scenarios give the possible states of the climate in The Netherlands for the next century. Projections of changes in precipitation were made for a time scale of 1 day. The urban drainage sector is, however, more interested in projections on shorter time scales. Specifically, time scales of 1 h or less. The aim of this research is to provide projections of precipitation at these shorter time scales based on the available daily scenarios. This involves an analysis of climate variables and their relations to precipitation at different time scales. On the basis of this analysis, one can determine a numeric factor to translate daily projections into shorter time scale projections.  相似文献   

Molybdenite Mineralization and Re‐Os Geochronology of the Escondida and Escondida Norte Porphyry Deposits,Northern Chile     

Bárbara Romero  Shoji Kojima  Chilong Wong  Walter Véliz  Joaquin Ruiz 《Resource Geology》2011,61(1):91-100

Molybdenum is an economically important subproduct of North Chilean porphyry‐type deposits, and thus spatial and temporal distribution of molybdenite as the primary Mo‐bearing mineral in the Escondida and Escondida Norte deposits were characterized using several mineralogical and chemical techniques and the Re‐Os dating method. Molybdenum is distributed extensively in the two deposits, and high molybdenum concentrations (>500 ppm) are recognized particularly in the chlorite‐sericite transitional zone between the potassic and sericitic zones. Two modes of occurrence of molybdenite are observed in the Escondida deposit: aggregates with Cu‐Fe‐sulfide minerals in fine veinlets (sulfide‐veinlet type), and monomineralic microveinlets associated with NE‐trending faults. The former and the latter yielded ages of 36.1 ± 0.2 Ma and 35.2 ± 0.2 Ma, respectively. Re‐Os dating of Escondida Norte molybdenites also show two distinct episodes, at 37.7 ± 0.3 Ma and a younger episode at 36.6 ± 0.2 Ma. These data indicate that the Escondida Norte is older than the main Escondida deposit. The Re‐Os age data combined with those of the porphyry emplacement suggest that the molybdenite mineralization in the Escondida district occurred as several short episodic pulses during the late‐magmatic to hydrothermal transition, and that the Cu‐Mo deposits were formed in a variable overall period spanning 1 to 5 m.y.  相似文献   

Characterization and facies analysis of the hydrovolcanic deposits of Montaña Pelada tuff ring: Tenerife,Canary Islands   总被引：1，自引：0，他引：1  

J. Carmona  C. Romero  J. Dóniz  A. García 《Journal of African Earth Sciences》2011,59(1):41-50

Montaña Pelada is a basaltic Pleistocene tuff ring located in the SE of Tenerife and it is composed of two edifices each with its distinct internal depositional distribution. A detailed stratigraphic analysis was carried out and ten facies were recognized. Deposits interpretation has revealed that water/magma ratio changes controlled the eruptive evolution, distinguishing three main stages of the eruption. Pyroclastic density currents were formed during the initial phreatomagmatic stages depositing the proximal facies, and transformed into turbulent dry surges during the second stage, indicating a reduction in the water/magma ratio. After deposition of these surges, the opening of an N–S fracture drove the eruption northwards creating a new edifice. The new hydrological conditions allowed the input of phreatic water, which resulted in high proportion of accidental lithics within characteristic of the deposits, increasing the water/magma ratio and reducing the fragmentation degree as can be recognized in the third stage. The evolution of the second tuff was similar, starting with radial-diluted pyroclastic surges and finishing with base surges deposits, suggesting lower water/magma ratio and higher fragmentation degree. Whereas the south cone originates dry pyroclastic surges and many tuff facies, northern one does not go beyond the deposition of a laminated tuff.  相似文献