Low-salinity plumes in the oceanic region of the Basque Country     

L. Ferrer  A. Fontán  J. Mader  G. Chust  M. González  V. Valencia  Ad. Uriarte  M.B. Collins 《Continental Shelf Research》2009,29(8):970-984

Low-salinity waters, within the upper layers of the water column, have been observed in the oceanic region of the southeastern limit of the Bay of Biscay (in March, 2007). This contribution assesses the potential role of large surface freshwater discharges from the Adour (France), Nervión, Oria, Deba, Urola, Urumea and Bidasoa (Basque Country) rivers, to explain the presence of these low-salinity waters. Such discharges, within the offshore waters, reached to at least 50 m in depth; likewise, extending over 15–20 km, in the horizontal. This pattern is confirmed by field data collected by offshore buoys, model results, and the analysis of satellite images. The presence of the low-salinity waters is corroborated by numerical simulations, performed by the ROMS (Regional Ocean Modeling System) hydrodynamic model, with the incorporation of river discharges. In order to simulate the freshwater movements and to identify their origin, particles were released at the river mouths and dispersed (by a Lagrangian particle-tracking model, LPTM), supplied by 3-hourly current fields derived from the ROMS model. The plumes of the Nervión, Oria, Urola and Urumea rivers appear to be the main factors contributing to the low-salinity field, at the offshore locations of the buoys. This pattern is related mainly to the prevailing oceano-meteorological conditions, over the period of analysis.  相似文献   

shinyNORRRM: A Cross-Platform Software to Calculate the CIPW Norm     

González-Guzmán  Reneé  Elizondo-Pacheco  Luis Alejandro  González-Roque  Abraham  Sánchez-Torres  Carlos Eduardo  Cárdenas-Muñoz  Kevin Samuel 《Mathematical Geosciences》2023,55(4):563-577

In this paper, a novelty-free software to assess an efficient CIPW Norm (± 0.006 wt.% in differences between input and output data) is presented. The package is available in the official repository for user-contributed R packages (CRAN: Comprehensive R Archive Network). The software is able to handle big data sets and considers minor and trace element compositions. The algorithm can calculate odd minerals in igneous rocks, such as cancrinite and calcite, adjust the Fe⁺³/Fe⁺² ratio in different standard approaches, and recalculate the compositions of the rocks in an anhydrous basis (100 ± 0.003 wt.% volatile-free adjusted). Furthermore, the package calculates several petrological parameters, and the graphical outputs are displayed following IUGS scheme standards. The prime aspect of shinyNORRRM is the symbiosis of native R functions with the R package’s shiny (Web Application Framework for R) to run the norm in a user-friendly interface. shinyNORRRM can be executed in any operating system and requires no previous programming knowledge, thus promising to be the universal computational program in this matter. The output data are printed in the standard comma-separated values (*.csv) format, which is highly compatible with general spreadsheet editors. In this work, the algorithm of our program is validated using already compiled whole-rock geochemical databases.

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Seismic risk assessment and hazard mapping in Nepal     

Chaulagain  Hemchandra  Rodrigues  Hugo  Silva  Vitor  Spacone  Enrico  Varum  Humberto 《Natural Hazards》2015,78(1):583-602

Natural Hazards - Seismic risk in the form of impending disaster has been seen from past records that moderate-to-large earthquakes have caused the loss of life and property in all parts of Nepal....  相似文献   

Cross-sectional growth in US cities from 1990 to 2000   总被引：1，自引：1，他引：0  

Rafael González-Val 《Journal of Geographical Systems》2015,17(1):83-106

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Solar-Cycle Variation of Subsurface Meridional Flow Derived with Ring-Diagram Analysis     

R. Komm  I. González Hernández  R. Howe  F. Hill 《Solar physics》2015,290(11):3113-3136

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Solar-Cycle Variation of Subsurface Zonal Flow     

R. Komm  R. Howe  I. González Hernández  F. Hill 《Solar physics》2014,289(9):3435-3455

We study the solar-cycle variation of the zonal flow in the near-surface layers of the solar convection zone from the surface to a depth of 16 Mm covering the period from mid-2001 to mid-2013 or from the maximum of Cycle 23 through the rising phase of Cycle 24. We have analyzed Global Oscillation Network Group (GONG) and Helioseismic and Magnetic Imager (HMI) Dopplergrams with a ring-diagram analysis. The zonal flow varies with the solar cycle showing bands of faster-than-average flows equatorward of the mean latitude of activity and slower-than-average flows on the poleward side. The fast band of the zonal flow and the magnetic activity appear first in the northern hemisphere during the beginning of Cycle 24. The bands of fast zonal flow appear at mid-latitudes about three years in the southern and four years in the northern hemisphere before magnetic activity of Cycle 24 is present. This implies that the flow pattern is a direct precursor of magnetic activity. The solar-cycle variation of the zonal flow also has a poleward branch, which is visible as bands of faster-than-average zonal flow near 50° latitude. This band appears first in the southern hemisphere during the rising phase of the Cycle 24 and migrates slowly poleward. These results are in good agreement with corresponding results from global helioseismology.  相似文献   

A Full-Sun Magnetic Index from Helioseismology Inferences     

I. González Hernández  M. Díaz Alfaro  K. Jain  W. K. Tobiska  D. C. Braun  F. Hill  F. Pérez Hernández 《Solar physics》2014,289(2):503-514

Solar magnetic indices are used to model the solar irradiance and ultimately to forecast it. However, the observation of such indices is generally limited to the Earth-facing hemisphere of the Sun. Seismic maps of the far side of the Sun have proven their capability to locate and track medium–large active regions at the non-visible hemisphere. We present here the possibility of using the average signal from these seismic far-side maps, combined with similarly calculated near-side maps, as a proxy to the full-Sun magnetic activity.  相似文献   

Near Infrared Spectra of two Asteroids with low Tisserand Invariant     

Julie Ziffer  Humberto Campins  Javier Licandro  Noemi Pinilla-Alonso  Yanga Fernandez  Schelte J. Bus 《Earth, Moon, and Planets》2005,97(3-4):203-212

We present near infrared reflectance spectra from 0.8 to 2.5 μm of two asteroids with low Tisserand invariant, 1373 Cincinnati and 2906 Caltech. We compare our spectra with cometary nuclei and other asteroids in their class. Asteroids Cincinnati and Caltech have Tisserand invariant values of 2.72 and 2.97, respectively, values less than 3 are considered suggestive of cometary origin. The observed spectral slopes in the near-infrared are consistent with both the spectra of cometary nuclei and of primitive asteroids. However, both asteroids have features in the near-infrared that are not seen in cometary nuclei, but are present in other X-type asteroids. 1373 Cincinnati has a sharp slope change between 0.75 and 1.0 μm and 2906 Caltech has a broad and shallow absorption between 1.35 and 2.2 μm. Our attempts to model the visible and near-infrared spectrum of these two objects, with the components successfully used by Emery and Brown (2004, Icarus 164, 104–121) to fit Trojan asteroids, did not yield acceptable fits.Visiting Astronomer at the Infrared Telescope Facility, which is operated by the University of Hawaii under contract to the National Aeronautics and Space Administration.  相似文献   

Orbital Elements of 2004 Perseid Meteoroids Perturbed by Jupiter     

Josep Maria Trigo-Rodriguez  Jeremie Vaubaillon  José Luís Ortiz  Alberto Castro-Tirado  Jordi Llorca  Esko Lyytinen  Martin Jelínek  Antonio de Ugarte Postigo  Pablo Santos Sanz  Francisco J. Aceituno Castro  Albert Sánchez Caso  Antonio Bernal González  Juan Pastor Erades  Francisco Ocaña 《Earth, Moon, and Planets》2005,97(3-4):269-278

Jupiter and Saturn produce important gravitational impulses on meteoroids released by comet 109P/Swift-Tuttle. The meteoroids from this comet once released follow retrograde orbits that during their periodic approaches to these planets (within 1.6 and 0.9 A.U., respectively) are impulsed gaining orbital energy. This perturbation effect is translated into a net inward shift in the node of the perturbed meteoroids. Such geometry with Jupiter occurred in 2004 over a meteoroid trail ejected by this comet during the 1862 A.D. return of the comet to perihelion. In order to study the predicted outburst produced by one-revolution meteoroids, the Spanish Photographic Meteor Network (SPMN) performed an extensive campaign. As a part of this observational effort here are presented 10 accurate meteoroid orbits. We discuss their origin by comparing them with the theoretical orbital elements of the dust trails intercepting the Earth during the 2004 Perseid return.  相似文献   

Gaseous Jets in Comet Hale-Bopp (1995 O1)     

Lederer  Susan M.  Campins  Humberto  Osip  David J.  Schleicher  David G. 《Earth, Moon, and Planets》1997,78(1-3):131-136

We report the identification of gas jets in comet Hale-Bopp in OH, NH, CN, C₂ and C₃. This is the first time OH and NH jets without an obvious optical dust jet counterpart have been identified in narrowband comet images. We also confirm the existence of CN jets as reported by Larson et al. (1997) and Mueller et al. (1998). Jet features can be seen in the March and April 1997 datasets, approximately a month before and after perihelion. Our results contribute to the understanding of both the chemical properties of the comet as well as the physical mechanisms necessary to produce these features. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献