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Elizabeth Mcleod Benjamin Poulter Jochen Hinkel Enrique Reyes Rodney Salm 《Ocean & Coastal Management》2010,53(9):507-517
Conservation managers and policy makers need tools to identify coastal habitats and human communities that are vulnerable to sea-level rise. Coastal impact models can help determine the vulnerability of areas and populations to changes in sea level. Model outputs may be used to guide decisions about the location and design of future protected areas and development, and to prioritize adaptation of existing protected area investments. This paper reviews state-of-the-art coastal impact models that determine sea-level rise vulnerability and provides guidance to help managers and policy makers determine the appropriateness of various models at local, regional, and global scales. There are a variety of models, each with strengths and weaknesses, that are suited for different management objectives. We find important trade-offs exist regarding the cost and capacity needed to run and interpret the models, the range of impacts they cover, and regarding the spatial scale that each operates which may overstate impacts at one end and underestimate impacts at the other. Understanding these differences is critical for managers and policy makers to make informed decisions about which model to use and how to interpret and apply the results. 相似文献
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Novelo-Casanova David A. Suárez Gerardo Cabral-Cano Enrique Fernández-Torres Enrique A. Fuentes-Mariles Oscar A. Havazli Emre Jaimes Miguel Á. López-Espinoza Erika D. Martin-Del Pozzo Ana Lillian Morales-Barrera Wendy V. Morales-Rodríguez Hipólito L. Nieto-Torres Amiel Rodríguez-Elizarrarás Sergio R. Solano-Rojas Darío Velasco-Herrera Victor M. 《Natural Hazards》2022,111(1):411-437
Natural Hazards - We present a Risk Atlas of Mexico City based on a Geographical Information System (RA-GIS). We identified the prevalent social risk to the more relevant hazards in Mexico City... 相似文献
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Rodolfo H. Barbá Jesús Maíz Apellániz Enrique Pérez Mónica Rubio Alberto Bolatto Cecilia Fariña Guillermo Bosch Nolan R. Walborn 《Astrophysics and Space Science》2009,324(2-4):309-313
We present the first high-spatial-resolution near-infrared (NIR) imaging of NGC604, obtained with the NICMOS camera onboard the Hubble Space Telescope (HST). These NICMOS broad-band images reveal new NIR point sources, clusters, and diffuse structures. We find an excellent spatial correlation between the 8.4 GHz radio continuum and the 2.2 μm nebular emission. Moreover, massive young stellar object candidates appear aligned with these radio peaks, reinforcing the idea that those areas are star-forming regions. Three different scaled OB associations are recognized in the NICMOS images. The brightest NIR sources in our images have properties that suggest that they are red supergiant stars, of which one was previously known. This preliminary analysis of the NICMOS images shows the complexity of the stellar content of the NGC604 nebula. 相似文献
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We have measured the vertical shear of the zonal winds in the cloud-haze upper layer of Saturn using Cassini ISS images obtained in the filters MT2 (753 nm methane absorption band, sensitive to the upper haze) and CB2 (adjacent continuum, sensitive to the lower cloud). Our radiative transfer models indicate that at the eastward jet peaks these filters are sensing clouds at the respective ∼100 mbar and ∼350 mbar levels. We have found a systematic velocity difference between those filters of 15 to 20 m s−1 only in the eastward jets peaks (27° S, 42° S, 55° S and 70° S) which implies a vertical shear of ∼10-20 m s−1 H−1. Our overall results agree with those derived from the thermal-wind relationship using CIRS thermal data [Fletcher, L.N., and 13 colleagues, 2008. Science 319, 79-81] and with previous equatorial measurements [Sánchez-Lavega, A., Hueso, R., Pérez-Hoyos, S., 2007. Icarus 187, 510-519]. 相似文献
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Anna Cabré Enrique Gaztañaga 《Monthly notices of the Royal Astronomical Society》2009,396(2):1119-1131
This is the second paper of a series where we study the clustering of luminous red galaxies (LRG) in the recent spectroscopic Sloan Digital Sky Survey (SDSS) data release, DR6, which has 75 000 LRG covering over 1 Gpc3 h −3 for 0.15 < z < 0.47 . Here, we focus on modelling redshift-space distortions in ξ(σ, π) , the two-point correlation in separate line-of-sight and perpendicular directions, at small scales and in the line-of-sight. We show that a simple Kaiser model for the anisotropic two-point correlation function in redshift space, convolved with a distribution of random peculiar velocities with an exponential form, can describe well the correlation of LRG on all scales. We show that to describe with accuracy the so-called 'fingers-of-God' (FOG) elongations in the radial direction, it is necessary to model the scale dependence of both bias b and the pairwise rms peculiar velocity σ12 with the distance. We show how both quantities can be inferred from the ξ(σ, π) data. From r ≃ 10 Mpc h −1 to r ≃ 1 Mpc h −1 , both the bias and σ12 are shown to increase by a factor of 2: from b = 2 to 4 and from σ12 = 400 to 800 km s−1 . The latter is in good agreement, within a 5 per cent accuracy in the recovered velocities, with direct velocity measurements in dark matter simulations with Ωm = 0.25 and σ8 = 0.85 . 相似文献
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Enrique Pérez-Montero Thierry Contini 《Monthly notices of the Royal Astronomical Society》2009,398(2):949-960
We study the relation between nitrogen and oxygen abundances as a function of metallicity for a sample of emission-line objects for which a direct measurement of the metallicity has been possible. This sample is representative of the very different conditions in ionization and chemical enrichment that we can find in the Universe. We first construct the N/O versus O/H ratio diagram, and discuss its large dispersion at all metallicity regimes. Using the same sample and a large grid of photoionization models covering very different values of the N/O ratio, we then study the most widely used strong-line calibrators of metallicity based on [N ii ] emission lines, such as N2 and O3N2. We demonstrate that these parameters underestimate the metallicity at low N/O ratios and vice versa. We also investigate the effect of the N/O ratio on different diagnostic diagrams used to discriminate narrow-line active galactic nuclei from star-forming regions, such as the [O iii ]/Hβ versus [N ii ]/Hα, and show that a large fraction of the galaxies catalogued as composite in this diagram can be, in fact, star-forming galaxies with a high value of the N/O ratio. Finally, using strong-line methods sensitive to the N/O abundance ratio, like N2O2 and N2S2, we investigate the relation between this ratio and the stellar mass for the galaxies of the Sloan Digital Sky Survey. We find, as in the case of the mass–metallicity relation, a correlation between these two quantities and a flattening of the relation for the most massive galaxies, which could be a consequence of the enhancement of the dispersion of N/O ratio in the high-metallicity regime. 相似文献
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