Meteorites and the early solar system II,edited by Dante S. Lauretta and Harry Y. McSween,Jr.     

Josep M. Trigo‐Rodríguez 《Meteoritics & planetary science》2008,43(5):989-991

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Management alternatives to offset climate change effects on Mediterranean fire regimes in NE Spain   总被引：1，自引：0，他引：1  

Lasse Loepfe  Jordi Martinez-Vilalta  Josep Pi?ol 《Climatic change》2012,115(3-4):693-707

Fire regime is affected by climate and human settlements. In the Mediterranean, the predicted climate change is likely to exacerbate fire prone weather conditions, but the mid- to long-term impact of climate change on fire regime is not easily predictable. A negative feedback via fuel reduction, for instance, might cause a non-linear response of burned area to fire weather. Also, the number of fires escaping initial control could grow dramatically if the fire meteorology is just slightly more severe than what fire brigades are prepared for. Humans can directly influence fire regimes through ignition frequency, fire suppression and land use management. Here we use the fire regime model FIRE LADY to assess the impacts of climate change and local management options on number of fires, burned area, fraction of area burned in large fires and forest area during the twenty-first century in three regions of NE Spain. Our results show that currently fuel-humidity limited regions could suffer a drastic shift of fire regime with an up to 8 fold increase of annual burned area, due to a combination of fuel accumulation and severe fire weather, which would result in a period of unusually large fires. The impact of climate change on fire regime is predicted to be less pronounced in drier areas, with a gradual increase of burned area. Local fire prevention strategies could reduce but not totally offset climate induced changes in fire regimes. According to our model, a combination of restoring the traditional rural mosaic and classical fire prevention would be the most effective strategy, as a lower ignition frequency reduces the number of fires and the creation of agricultural fields in marginal areas reduces their extent.  相似文献   

Recent results on X-ray novae and microquasars at radio and infrared wavelengths     

Josep Martí 《Astrophysics and Space Science》2001,276(1):3-12

The Spanish MINISAT program has been structured in three main stagesplus several associated developments, achieving a modular family of lowcost platforms in the small satellite segment, designed to use mainly in lowearth orbit (LEO) applications. The first stage of the MINISAT programhave concluded with the complete development and orbit qualification ofthe platform MINISAT 0 together with the operational experiences is beingachieved to perform the scientific mission 01, launched on April 21^st 1997. The second stage of the MINISAT program consist of the modularupgrading of the platform 0 to reach the maximum performances orplatform MINISAT 1 to do earth observation missions. The first missionwith the platform 1 started the phase A of feasibility study in 1995. Thethird stage of the MINISAT program will consist of the development of theplatform MINISAT 2 that will be an adaptation of the platform MINISAT1 to be able to do communication missions even in the geostationary orbit.  相似文献   

Stratigraphic and structural controls on groundwater flow in an outcropping fossil fan delta: the case of Sant Llorenç del Munt range (NE Spain)     

Marc Anglés  Albert Folch  Oriol Oms  Eudald Maestro  Josep Mas-Pla 《Hydrogeology Journal》2017,25(8):2467-2487

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New archaeo‐stratigraphic data for the TD6 level in relation to Homo antecessor (Lower Pleistocene) at the site of Atapuerca,north‐central Spain     

Antoni Canals  Josep Vallverdú  Eudald Carbonell 《Geoarchaeology》2003,18(5):481-504

The sediments of the TD6 level of Gran Dolina Cave at Sierra de Atapuerca, Burgos, Spain, consist of a series of mud flows with angular clasts. The TD6 deposit has two parts: an upper part, known as the Aurora stratum, which yields Homo antecessor remains, and a lower part with rather homogeneous sediment. The excavation of TD6 level did not reveal a sequence of diachronic occupations. Instead, the contextual and stratigraphic studies permitted us to describe and delimit the micro‐units forming the TD6 deposit. The study of the distribution of archaeological remains based on vertical archaeological profiles, using an archaeo‐stratigraphic method, allowed us to document the occurrence of a series of archaeological levels within the apparent homogeneous deposit. Variations in the density of archaeological remains along the archaeo‐stratigraphic levels permitted us to define two occupational cycles in TD6. These cycles seemingly show increased activities through time, culminating in the Aurora level with the presence of cannibalized Homo antecessor remains. © 2003 Wiley Periodicals, Inc.  相似文献   

Study of the transfer between libration point orbits and lunar orbits in Earth–Moon system     

Yu Cheng  Gerard Gómez  Josep J. Masdemont  Jianping Yuan 《Celestial Mechanics and Dynamical Astronomy》2017,128(4):409-433

This paper is devoted to the study of the transfer problem from a libration point orbit of the Earth–Moon system to an orbit around the Moon. The transfer procedure analysed has two legs: the first one is an orbit of the unstable manifold of the libration orbit and the second one is a transfer orbit between a certain point on the manifold and the final lunar orbit. There are only two manoeuvres involved in the method and they are applied at the beginning and at the end of the second leg. Although the numerical results given in this paper correspond to transfers between halo orbits around the \(L_1\) point (of several amplitudes) and lunar polar orbits with altitudes varying between 100 and 500 km, the procedure we develop can be applied to any kind of lunar orbits, libration orbits around the \(L_1\) or \(L_2\) points of the Earth–Moon system, or to other similar cases with different values of the mass ratio.  相似文献   

Spatial collinear restricted four-body problem with repulsive Manev potential     

Esther Barrabés  Josep M. Cors  Claudio Vidal 《Celestial Mechanics and Dynamical Astronomy》2017,129(1-2):153-176

We outline some aspects of the dynamics of an infinitesimal mass under the Newtonian attraction of three point masses in a symmetric collinear relative equilibria configuration when a repulsive Manev potential (\(-1/r +e/r^{2}\)), \(e>0\), is applied to the central mass. We investigate the relative equilibria of the infinitesimal mass and their linear stability as a function of the mass parameter \(\beta \), the ratio of mass of the central body to the mass of one of two remaining bodies, and e. We also prove the nonexistence of binary collisions between the central body and the infinitesimal mass.  相似文献   

Effects of large-scale habitat variability on condition of demersal exploited fish in the north-western Mediterranean   总被引：4，自引：0，他引：4  

Lloret  Josep; Gil de Sola  Luis; Souplet  Arnauld; Galzin  Rene 《ICES Journal of Marine Science》2002,59(6):1215-1227

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Long-term variability of growth and recruitment of cod (Gadus morhua) off Greenland   总被引：1，自引：0，他引：1  

Ratz  Hans-Joachim; Lloret  Josep 《ICES Journal of Marine Science》2005,62(7):1310-1321

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Attenuation and source parameters at Deception Island (South Shetland Islands,Antarctica)     

Josep Vila  Antoni M. Correig  Joan Martí 《Pure and Applied Geophysics》1995,144(2):229-250

Deception Island is the most active volcano of the South Shetland Islands-Antarctic Peninsula group, experiencing eruptions in 1967, 1969 and 1970. Local attenuation derived from coda analysis and source parameters derived from Brune's model, for well located seismic events, have been studied in order to complement the available geophysical information. Results show abnormally lowQ ₀ values and an abnormally high frequency dependence, as well as large dispersion. These factors are strongly dependent on the path travelled by the seismic wave. Retrieved values of the source parameters (stress drop, seismic moment and source radius), are again abnormally low compared to world-wide average values, for example, those obtained for the Oroville, California aftershock series between June and September, 1976. These results are consistent with some aspects of the geology of Deception Island, such as the very high degree of fracturing and faulting, and the existence of a strong hydrothermal alteration affecting most of the subaerial volcanic rocks. Moreover, the pattern defined for the lateral variations ofQ ₀ shows minimum values in the inner bay of the island, close to the most recent eruption vents. A large reduction in spectral amplitudes over a particular frequency range occurs in several observations, corresponding to the path crossing the zone of highest attenuation. This observation suggests the existence of a hot magmatic intrusion produced during the most recent eruption, and coincides with the superficial low density mass distribution obtained from the gravimetric model and the long wave magnetic field component obtained from magnetic surveys. The width of this intrusion is estimated to be about 200 m, in agreement with the previous results obtained analyzing residuals of the location of seismic events.  相似文献