California coastal management with a changing climate   总被引：2，自引：0，他引：2  

Ellen Hanak  Georgina Moreno 《Climatic change》2012,111(1):45-73

With over 2,000 miles (3,218 km) of ocean and estuarine coastline, California faces significant coastal management challenges as a result of climate change-induced sea level rise. Under high emission scenarios, recent models predict 1.4 m or more of sea level rise by 2100, accompanied by increasing storm surges. This article investigates the most important issues facing coastal managers, explores the policy tools available for adapting to the impacts of climate change, assesses institutional constraints to adaptation, and identifies priorities for future research and policy action. We find that adaptation tools exist for dealing with anticipated increases in coastal erosion and flooding, but they involve significant costs and tradeoffs. In particular, coastal armoring, such as seawalls, can protect developed coastal lands, but destroys beaches and habitat. Although California already has policies and institutions that aim to balance the competing objectives for coastal development, management agencies are at the early stages of understanding how to facilitate adaptation. Research priorities to inform coastal adaptation planning include: (i) inventorying coastal resources to provide a firmer basis for balancing decisions on property and habitat protection, (ii) identifying opportunities for coastal habitat migration, (iii) assessing the vulnerabilities of existing and planned coastal infrastructure, and (iv) experimenting with alternatives to armoring as a way of managing the changing coastline.  相似文献   

Lateglacial and Holocene palaeohydrology in the western Mediterranean region: The Lake Estanya record (NE Spain)   总被引：3，自引：0，他引：3  

Mario Morelln  Blas Valero-Garcs  Teresa Vegas-Vilarrúbia  Penlope Gonzlez-Sampriz   scar Romero  Antonio Delgado-Huertas  Pilar Mata  Ana Moreno  Mayte Rico  Juan Pablo Corella 《Quaternary Science Reviews》2009,28(25-26):2582-2599

The multi-proxy analysis of sediment cores recovered in karstic Lake Estanya (42°02′ N, 0°32′ E; 670 m a. s. l., NE Spain), located in the transitional area between the humid Pyrenees and the semi-arid Central Ebro Basin, provides the first high-resolution, continuous sedimentary record in the region, extending back the last 21 000 years. The integration of sedimentary facies, elemental and isotopical geochemistry and biogenic silica, together with a robust age model based on 17 AMS radiocarbon dates, enables precise reconstruction of the main hydrological and environmental changes in the region during the last deglaciation.Arid conditions, represented by shallow lake levels, predominantly saline waters and reduced organic productivity occurred throughout the last glacial maximum (21–18 cal kyrs BP) and the lateglacial, reaching their maximum intensity during the period 18–14.5 cal kyrs BP (including Heinrich event 1) and the Younger Dryas (12.9–11.6 cal kyrs BP). Less saline conditions characterized the 14.5–12.6 cal kyrs BP period, suggesting higher effective moisture during the Bölling/Allerød. The onset of more humid conditions started at 9.4 cal kyrs, indicating a delayed hydrological response to the onset of the Holocene which is also documented in several sites of the Mediterranean Basin. Higher, although fluctuating, Holocene lake levels were punctuated by a mid Holocene arid period between 4.8 and 4.0 cal kyrs BP. A major lake-level rise occurred at 1.2 cal kyrs BP, conducive to the establishment of conditions similar to the present and interrupted by a last major water level drop, occurring around 800 cal yrs BP, which coincides with the Medieval Climate Anomaly.The main hydrological stages in Lake Estanya are in phase with most Western Mediterranean and North Atlantic continental and marine records, but our results also show similarities with other Iberian and northern African reconstructions, emphasizing peculiarities of palaeohydrological evolution of the Iberian Peninsula during the last deglaciation.  相似文献   

The AD 1300–1700 eruptive periods at Tungurahua volcano,Ecuador, revealed by historical narratives,stratigraphy and radiocarbon dating     

J.-L. Le Pennec  D. Jaya  P. Samaniego  P. Ramón  S. Moreno Yánez  J. Egred  J. van der Plicht 《Journal of Volcanology and Geothermal Research》2008

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Abrupt Vegetation and Climate Changes During the Last Glacial Maximumand Last Termination in The Chilean Lake District: A Case Study from Canal De La Puntilla (41°S)     

P.I. Moreno  T.V. Lowell  G.L. Jacobson Jr  & G.H. Denton 《Geografiska Annaler: Series A, Physical Geography》1999,81(2):285-311

ABSTRACT. Multiple overlapping and replicate pollen stratigraphies from Canal de la Puntilla (40°57’09”S, 72°54’18”W, 120 m elevation) reveal that a Nothofagus dombeyi-type parkland occupied the Valle Central of the Chilean Lake District during the portion of the Last Glacial Maximum between 20,200 and about 14,600 ¹⁴C yr BP . Dominating this landscape was Nothofagus dombeyi-type and Gramineae, accompanied by taxa commonly found today in Subantarctic environments and above the Andean tree-line in the Lake District (Perezia-type, Valeriana, and Huperzia selago), along with cushion bog taxa characteristic of Magellanic Moorlands (Donatia fascicularis and Astelia pumila). Within this open landscape Nothofagus dombeyi-type expanded between 20,200 and 15,800 ¹⁴C yr BP , interrupted by a brief reversal between 19,200 and 18,800 ¹⁴ C yr BP and followed by a prominent increase in Gramineae pollen between 15,800 and about 14,600 ¹⁴C yr BP . A major rise of Nothofagus dombeyi-type began at about 14,600 ¹⁴C yr BP , followed by decline in non-arboreal taxa and a remarkable expansion of North Patagonian Rain Forest taxa in pulses centered at 14,200 and 13,000 ¹⁴C yr BP . Podocarpus nubigena expanded between 12,200 and 9800 ¹⁴C yr BP , along with increases in Misodendrum and Maytenus disticha-type between 11,000 and 9800 ¹⁴C yr BP. Paleovegetation records suggest that mean annual temperature was 6–7°C colder than at present during the coldest episodes between 20,200 and about 14,600 ¹⁴C yr BP , with twice the modern annual precipitation between 20,200 and 13,000 ¹⁴C yr BP, suggesting a northward shift and intensification of westerly stormtracks. Slight climate warming occurred between 20,200 and 15,800 ¹⁴C yr BP , interrupted by cooling events at 19,200 and 15,800 ¹⁴C yr BP . The initial warming of the last termination started at 14,600 ¹⁴C yr BP , followed by warming pulses at 14,200 and 13,000 ¹⁴C yr BP. These events brought glacial conditions to a cool-temperate climate, slightly cooler and wetter than modern climate, accounting for a total temperature recovery of ≥5°C by about 13,000 ¹⁴C yr BP . A general reversal in trend is inferred with cooling events at 12,200 and 11,000 ¹⁴C yr BP .  相似文献   

Spatial transferability of the physically based model TRIGRS using parameter ensembles     

Lotte de Vugt  Thomas Zieher  Barbara Schneider-Muntau  Mateo Moreno  Stefan Steger  Martin Rutzinger 《地球表面变化过程与地形》2024,49(4):1330-1347

The development of better, more reliable and more efficient susceptibility assessments for shallow landslides is becoming increasingly important. Physically based models are well-suited for this, due to their high predictive capability. However, their demands for large, high-resolution and detailed input datasets make them very time-consuming and costly methods. This study investigates if a spatially transferable model calibration can be created with the use of parameter ensembles and with this alleviate the time-consuming calibration process of these methods. To investigate this, the study compares the calibration of the model TRIGRS in two different study areas. The first study area was taken from a previous study where the dynamic physically based model TRIGRS was calibrated for the Laternser valley in Vorarlberg, Austria. The calibrated parameter ensemble and its performance from this previous study are compared with a calibrated parameter ensemble of the model TRIGRS for the Passeier valley in South Tyrol, Italy. The comparison showed very similar model performance and large similarities in the calibrated geotechnical parameter values of the best model runs in both study areas. There is a subset of calibrated geotechnical parameter values that can be used successfully in both study areas and potentially other study areas with similar lithological characteristics. For the hydraulic parameters, the study did not find a transferable parameter subset. These parameters seem to be more sensitive to different soil types. Additionally, the results of the study also showed the importance of the inclusion of detailed information on the timing of landslide initiation in the calibration of the model.  相似文献   

Hydrodynamical models of elliptical galaxies     

E. Moreno  P. Pi§mi§ 《Celestial Mechanics and Dynamical Astronomy》1988,45(1-3):81-82

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An assessment of the spatial heterogeneity of environmental disturbance within an enclosed harbour through the analysis of meiofauna and nematode assemblages   总被引：3，自引：1，他引：2  

M. Moreno  T.J. Ferrero  I. Gallizia  L. Vezzulli  G. Albertelli  M. Fabiano 《Estuarine, Coastal and Shelf Science》2008,77(4):565-576

Significant spatial heterogeneity in the abundance and composition of meiofaunal and nematode assemblages was described inside the Genoa-Voltri harbour (Genoa, Italy) in relation to variation in the main environmental variables. In harbour sediments characterized by low Eh values and high organic matter concentrations, total meiofauna abundance was lower (948 ± 919 ind 10 cm⁻²), nematode individual biomass was higher (0.17 ± 0.07 μg C), kinorhynchs and tanaids were completely absent, and the nematode assemblage was dominated by the genera Terschellingia, Sabatieria (pulchra group) and Paracomesoma. In contrast, in sediment characterized by lower levels of organic pollution, meiofaunal abundance was higher (1085 ± 737 ind 10 cm⁻²), nematode individual biomass was lower (0.11 ± 0.04 μg C), kinorhynchs and tanaids were present and the nematodes were dominated by the genera Desmodora, Daptonema, Anticoma and Halalaimus.Environmental disturbance as assessed by the analysis of meiofaunal and nematode assemblages and sediment environmental variables changed significantly over a scale hundreds of meters, but did not follow a gradient from the inner to the outer harbour. Analysis of nematode assemblages is proposed as a useful tool for the identification of environmental risk areas which may assist in the development of good planning, monitoring programmes and better management of harbour ecosystems.  相似文献   

Specialisation changes in European regions: the role played by externalities across regions   总被引：1，自引：1，他引：0  

Toni Mora  Rosina Moreno 《Journal of Geographical Systems》2010,12(3):311-334

This paper seeks to determine the factors underpinning changes in regional specialisation patterns in the European Union between 1991 and 2002. First, we consider a set of determinants previously identified in the regional literature, including agglomeration effects and other specific regional factors (business cycle, amount of investment, etc.). However, we then also take into account the fact that the evolution in a region’s specialisation pattern may be affected by the specialisation behaviour of other regions. Thus, not only do we consider the pattern of evolution in a region’s most proximate neighbours but we also examine that of their regional peers, i.e., regions with a similar specialisation pattern independent of their location. Notwithstanding, our empirical evidence indicates that physical distance still plays a very significant, and even more influential, role than similarity in specialisation.  相似文献   

Uppermost Lower Aptian transgressive records in Mexico and Spain: chronostratigraphic implications for the Tethyan sequences     

Josep A. Moreno‐Bedmar  Telm Bover‐Arnal  Ricardo Barragán  Ramon Salas 《地学学报》2012,24(4):333-338

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Millennial-scale variability in Southern Hemisphere westerly wind activity over the last 5000 years in SW Patagonia     

P.I. Moreno  J.P. François  R.P. Villa-Martínez  C.M. Moy 《Quaternary Science Reviews》2009,28(1-2):25-38

Here we report results from a high-resolution palynological record and stratigraphic/geochronologic data related to a Neoglacial event in Torres del Paine National Park, southern Chile (51°S, 71°W), to investigate climatic variations in Southwest Patagonia during the last 5000 years. The record reveals a stepwise expansion of Nothofagus-dominated woodlands and forests with discrete pulses at 4400, 2900, 1300, and 570 cal yr BP. Superimposed upon this trend we identify a relative opening of the woodlands between 4100–2900 and 2300–1300 cal yr BP. Closed-canopy forests dominated the landscape between 570–60 cal yr BP, followed by a rapid decline at the end of the 19th century that coincided with intense fire activity and the appearance of Rumex cf. acetocella, an exotic species introduced by European settlers. We interpret these changes as variations in the intensity and/or position of the southern margin of the westerly winds, which culminated with a net eastward shift of the forest–steppe ecotone during the Little Ice Age. We propose that millennial-scale changes in either the latitudinal position and/or the overall strength of the southern westerlies may be responsible for vegetation changes, fire occurrence, and the dynamic behavior of Patagonian glaciers during the last 5000 years. Because the modern maximum in near-surface wind velocities and precipitation is located between 48° and 50°S, we suggest that the core of the southern westerlies may have achieved this modern position ～570 years ago.  相似文献