The economic impact of future increase in tropical cyclones in Japan   总被引：2，自引：1，他引：1  

Christian Webersik  Miguel Esteban  Tomoya Shibayama 《Natural Hazards》2010,55(2):233-250

This article estimates the non-first-order economic loss in Japan due to a future increase in tropical cyclones. One possible effect of global warming could be the increase in intensity of tropical cyclones. Using historical storm tracks between the years 1978 and 2007 and altering their intensities due to this potential increase in their intensity, this paper calculates the future potential regional GDP loss in a certain area that is affected by tropical cyclones. Most of the literature is concerned with physical damage and the loss of lives due to tropical cyclones. However, there are additional economic costs when sustained wind speeds are higher than 30 knots (55.56 km/h), a level that generally will lead to a precautionary cessation of many human activities. Using a Monte Carlo simulation, the paper calculates the potential economic costs for the year 2085 under a climate change scenario with a linear one-per cent yearly increase in CO₂. Using a spatial distribution of economic activity in Japan, it is possible to forecast which parts of the country are likely to experience the highest loss risk.  相似文献   

Scholte waves on fluid-solid interfaces by means of an integral formulation     

Manuel Carbajal-Romero  Esteban Flores-Mendez  Norberto Flores-Guzmán  Jaime Núñez-Farfán  Enrique Olivera-Villaseñor  Francisco José Sánchez-Sesma 《Geofísica Internacional》2013,52(1):21-30

The present work shows the propagation of Scholte interface waves at the boundary of a fluid in contact with an elastic solid, for a broad range of solid materials. It has been demonstrated that by an analysis of diffracted waves in a fluid it is possible to infer the mechanical properties of the elastic solid medium, specifically, its propagation velocities. For this purpose, the diffracted wave field of pressures and displacements, due to an initial wave of pressure in the fluid, are expressed using boundary integral representations, which satisfy the equation of motion. The source in the fluid is represented by a Hankel’s function of second kind and zero order. The solution to this wave propagation problem is obtained by means of the Indirect Boundary Element Method, which is equivalent to the well-known Somigliana representation theorem. The validation of the results is carried out by using the Discrete Wave Number Method and the Spectral Element Method. Firstly, we show spectra of pressures that illustrate the behavior of the fluid for each solid material considered, then, we apply the Fast Fourier Transform to show results in time domain. Snapshots to exemplify the emergence of Scholte’s waves are also included.  相似文献   

Variable effects of forest canopies on snow processes in a valley of the central Spanish Pyrenees     

Alba Sanmiguel-Vallelado  Juan I. López-Moreno  Enrique Morán-Tejeda  Esteban Alonso-González  Francisco M. Navarro-Serrano  Ibai Rico  J. Julio Camarero 《水文研究》2020,34(10):2247-2262

Snowpacks and forests have complex interactions throughout the large range of altitudes where they co-occur. However, there are no reliable data on the spatial and temporal interactions of forests with snowpacks, such as those that occur in nearby areas that have different environmental conditions and those that occur during different snow seasons. This study monitored the interactions of forests with snowpacks in four forest stands in a single valley of the central Spanish Pyrenees during three consecutive snow seasons (2015/2016, 2016/2017 and 2017/2018). Daily snow depth data from time-lapse cameras were compared with snow data from field surveys that were performed every 10–15 days. These data thus provided information on the spatial and temporal changes of snow–water equivalent (SWE). The results indicated that forest had the same general effects on snowpack in each forest stand and during each snow season. On average, forest cover reduced the duration of snowpack by 17 days, reduced the cumulative SWE of the snowpack by about 60% and increased the spatial heterogeneity of snowpack by 190%. Overall, forest cover reduced SWE total accumulation by 40% and the rate of SWE accumulation by 25%. The forest-mediated reduction of the accumulation rate, in combination with the occasional forest-mediated enhancement of melting rate, explained the reduced duration of snowpacks beneath forest canopies. However, the magnitude and timing of certain forest effects on snowpack had significant spatial and temporal variations. This variability must be considered when selecting the location of an experimental site in a mountainous area, because the study site should be representative of surrounding areas. The same considerations apply when selecting a time period for study.  相似文献   

Forests and water in South America          下载免费PDF全文

Julia Jones  Auro Almeida  Felipe Cisneros  Andres Iroumé  Esteban Jobbágy  Antonio Lara  Walter de Paula Lima  Christian Little  Carlos Llerena  Luis Silveira  Juan Camilo Villegas 《水文研究》2017,31(5):972-980

South America is experiencing rapid change in forest cover, of both native and planted forest. Forest cover loss is primarily attributable to fire, logging, and conversion of native forest to agriculture, pasture, and forest plantations, and types of change vary within and among the many diverse types of forests in South America. Major changes in forest cover and growing policy concerns underscore an urgent need for research on sustainable forest management and water ecosystem services in South America. Differences in land ownership and management objectives create trade‐offs between wood production and water ecosystem services from forests. Work is needed to quantify how forest change and management affect ecosystem services, such as wood production versus water provision. Current scientific understanding of forest management effects on water ecosystem services in South America has important limitations, including a scarcity of long‐term records and few long‐term integrated watershed studies. Industry, government, universities, and local communities should collaborate on integrated applied studies of forests and water. Data archiving and publically available data are required. The creation of national networks and a multi‐country South America network to identify and implement common water research protocols, share results, and explore their implications would promote common and well‐supported policies. Hydrologists working in South America are well placed to tackle the challenges and opportunities for collaborative research that will maintain the intrinsic values and water ecosystem services provided by South America's forests.  相似文献   

Neutral hydrogen observations onHii regions     

Esteban Bajaja  Silvia L. Garzoli 《Astrophysics and Space Science》1973,24(1):65-82

Nine of the cataloguedHii regions in the southern hemisphere have been selected for correlation with neutral hydrogen observed at the 21 cm line.The radiotelescope used for theHi line observations was the 30 m Carnegie telescope of the Instituto Argentino de Radioastronomía and the 56 channel, 10 KHz bandwidth receiver.The observational results are analyzed for eachHii region. They are compared with previous optical and radio results.For three of the nine observed regions it has been possible to find neutral hydrogen in absorption with similar velocities. In three cases absorption has been found but no component at theHii region velocity is seen. Finally in three cases, it has not been possible to find any absorption at all.Member of the Carrera del Investigador Científico del Cosejo Nacional de Investigaciones Científicas y Técnicas.  相似文献   

Post-fire management effects on sediment (dis)connectivity in Mediterranean forest ecosystems: Channel and catchment response     

Javier González-Romero  Manuel López-Vicente  Elena Gómez-Sánchez  Esther Peña-Molina  Pablo Galletero  Pedro Plaza-Alvarez  Daniel Moya  Jorge De las Heras  Manuel Esteban Lucas-Borja 《地球表面变化过程与地形》2021,46(13):2710-2727

Forest fires and post-fire practices influence sediment connectivity (SC). In this study, we use the ‘aggregated index of connectivity’ (AIC) to assess SC in five Mediterranean catchments (198–1090 ha) affected by a wildfire in 2012 in south-eastern Spain. Two temporal scenarios were considered, immediately after the fire and before post-fire management, and 2 years after the fire including all practices (hillslope barriers, check-dams, afforestation, salvage logging and skid trails). One LiDAR (light detection and ranging)-derived digital elevation model (DEM, 2 m × 2 m resolution) was generated, per scenario. The five catchment outlets were established as the computation target (AIC_OUT), and structural and functional SC were calculated. Index outputs were normalized to make the results of the non-nested catchments comparable (AIC_N-OUT). The output analysis includes the SC distribution along the catchments and at local scale (929 sub-catchments, 677 in the burned area), the hillslope and channel measures' effect on SC, and a sedimentological analysis using observed area-specific sediment yield (SSY) at 10 new (built after post-fire practices) concrete check-dams located in the catchments (SSY = 1.94 Mg ha⁻¹ yr⁻¹; σ = 1.22). The catchments with more circular shapes and steeper slopes were those with higher AIC_N-OUT. The structural SC maps – removing the rainfall erosivity influence – allowed evaluating the actual role played by the post-fire practices that reduced SC ( $\overline{x}$= − 1.19%; σ = 0.41); while functional SC was linked to the actual change of SC ( $\overline{x}$= + 5.32%; σ = 0.62). Hillslope treatments resulted in significant changes on AIC_N-OUT at sub-catchment scale with certain disconnectivity. A good and positive correlation was found between the SSY and the changes of AIC_N-OUT. However, the coarse DEM resolution explained the lack of effect of the rock check-dams – located on the secondary channels – on AIC_N-OUT. AIC_N-OUT proved to be a useful tool for decision making in post-fire restoration, but an optimal input data is still necessary to refine calculations.  相似文献   

Carbonate lithofacies as paleolatitude indicators: problems and limitations     

G. Carannante  M. Esteban  J. D. Milliman  L. Simone 《Sedimentary Geology》1988,60(1-4):333-346

Detailed study of Miocene carbonates in the Mediterranean region and their analogues on modern carbonate shelves (in the Mediterranean Sea, Brazil and other areas) reveals at least three major types of carbonate platform lithofacies in addition to the classic tropical coral reef (chlorozoan) lithofacies: (a) chloralgal lithofacies, similar to the chlorozoan, but without hermatypic corals; (b) rhodalgal lithofacies, characterized by abundant encrusting coralline algae; and (c) molechfor lithofacies, consisting of benthic foraminifers, molluscs, echinoids, bryozoans and barnacles. These carbonate lithofacies present complex distribution patterns seemingly related primarily to latitude and depth that control water temperature, although other factors (e.g., water circulation, river discharge, suspended sediment) controlling water salinity and temperature, nutrient content, light penetration, etc., also play important roles. Chloralgal and rhodalgal lithofacies can be considered two transitional terms between the two end-members: the chlorozoan lithofacies, which characterizes shallow tropical shelves; and the molechfor lithofacies, which characterizes colder and/or deeper areas. Detailed textural and sequential analysis are required for satisfactory interpretation of these lithofacies in ancient rocks.  相似文献   

Phytoplankton absorption spectra along the water column in deep North Patagonian Andean lakes (Argentina)     

Gonzalo Prez  Claudia Queimalios  Esteban Balseiro  Beatriz Modenutti 《Limnologica》2007,37(1):3-16

During a summer period we studied the vertical variation of in vivo and chlorophyll a specific phytoplankton absorption spectra in relation to the underwater light climate of ten deep North Patagonian Andean lakes of Argentina. The lakes were thermally stratified, and the underwater light climate was characterized by extended euphotic zones which included highly illuminated epilimnetic layers (both UVR and PAR) and metalimnia exposed to dim blue-green light. Most of the lakes presented the development of Deep Chlorophyll Maxima (DCM) at the metalimnetic layers, near 1% of surface PAR irradiance. Analyzing the fourth-derivative plots of in vivo phytoplankton absorption spectra [d^IVa_ph(λ)], we were able to identify several maxima absorption values attributed to different pigments. Considering lakes with DCM, a significant positive linear relationship was found between d^IVa_ph (495–500 nm) normalized by chlorophyll a and downward irradiance. Indeed, a negative significant relationship was found between d^IVa_ph (495–500 nm) normalized by chlorophyll a and diffuse PAR attenuation coefficients. These results point out an increase in the relative concentration of different carotenoids at surface layers indicating the role of photoprotection of these pigments. On the other hand, significant negative linear relationships were found between fourth-derivative spectra normalized by chlorophyll a at 650, 590–595, 560–565 and 520–525 nm and downward irradiance. These results indicated an increase in the relative concentration of photosynthetic accessory pigments at deep layers of the euphotic zone. Furthermore, we found a decrease in depth of specific absorption spectra at 440, 670 nm and in the ratio a_ph* (440 nm) to a_ph* (670 nm). This pattern was associated with the package effect concept. The increase in relative photosynthetic accessory pigment concentrations and the decrease in values of specific absorption spectra at the bottom of the euphotic zone were attributed to changes in phytoplankton communities between surface and deep layers. These outcomes pointed out that the underwater light climate and temperature water structure are, like in marine systems, very important factors governing the distribution of phytoplanktonic organisms. In addition, the possession of specific photosynthetic accessory pigments suggests that dominant species in the DCM are well adapted to these dim blue-green light scenarios.  相似文献   

Poverty and citizenship: Sociological perspectives on water services and public-private participation   总被引：1，自引：0，他引：1  

José Esteban Castro 《Geoforum》2007,38(5):756-771

This article focuses on the arguments used to support private sector participation (PSP) in the provision of water and sanitation services (WSS) since the 1980s. It addresses the following questions: what was the historical evidence informing the claim that promoting PSP would be the best instrument for reducing water poverty? What are the principles that provided the foundation for this claim? And, what has been the empirical record of the resulting WSS policies? It argues that early neoliberal WSS policies since the 1980s were not intended to expand services to the poor. A pro-poor rhetoric was added to these policies since the 1990s, probably as a result of increasing citizen unrest in developing countries and the failure of privatized WSS projects in the Americas and Europe. However, the claim that PSP can provide the solution to public sector failure in extending coverage of essential WSS to the poor has little ground both in the theoretical literature and in the historical record. As could have been expected from the accumulated knowledge about the relationship between market-driven WSS and the poor, the recent experience with PSP projects has been disappointing. In practice these policies not only have failed to extend these essential services to the poor but have also contributed to deepening existing inequalities of power resulting in the weakening of state, local government, and civil society capacities to exercise democratic control over private water monopolies in most developing countries. Reversing this imbalance is one of the crucial challenges ahead in order to achieve the Millennium Development Goals. However, the article argues that the inertial forces set in motion by the neoliberal model of water policy based on market-centred governance of water and WSS remains the crucial obstacle for the achievement of the goals.  相似文献   

An assessment of uncertainties in VS profiles obtained from microtremor observations in the phased 2018 COSMOS blind trials     

Asten  Michael W.  Yong  Alan  Foti  Sebastiano  Hayashi  Koichi  Martin  Antony J.  Stephenson  William J.  Cassidy  John F.  Coleman  Jacie  Nigbor  Robert  Castellaro  Silvia  Chimoto  Kosuke  Cornou  Cécile  Cho  Ikuo  Hayashida  Takumi  Hobiger  Manuel  Kuo  Chun-Hsiang  Macau  Albert  Mercerat  E. Diego  Molnar  Sheri  Pananont  Passakorn  Pilz  Marco  Poovarodom  Nakhorn  Sáez  Esteban  Wathelet  Marc  Yamanaka  Hiroaki  Yokoi  Toshiaki  Zhao  Don 《Journal of Seismology》2022,26(4):757-780

Journal of Seismology - Site response is a critical consideration when assessing earthquake hazards. Site characterization is key to understanding site effects as influenced by seismic site...  相似文献