Reply to Discussion of “Perceptual models of uncertainty for socio-hydrological systems: a flood risk change example”*     

Ida K. Westerberg  Giuliano Di Baldassarre  Keith J. Beven  Gemma Coxon  Tobias Krueger 《水文科学杂志》2020,65(Z2):2001-2003

ABSTRACT

Ertsen discusses the representation of reality and uncertainty in our paper, raising three critical points. In response to the first, we agree that discussion of different interpretations of the concept of uncertainty is important when developing perceptual models – making different uncertainty interpretations explicit was a key motivation behind our method. Secondly, we do not, as Ertsen suggests, deny anyone who is not a “certified” scientist to have relevant knowledge. The elicitation of diverse views by discussing perceptual models is a basis for open discussion and decision making. Thirdly, Ertsen suggests that it is not useful to treat socio-hydrological systems as if they exist. We argue that we act as “pragmatic realists” in most practical applications by treating socio-hydrological systems as an external reality that can be known. But the uncertainty that arises from our knowledge limitations needs to be recognized, as it may impact on practical decision making and associated costs.  相似文献   

Exploring the role of risk perception in influencing flood losses over time     

E. Ridolfi  F. Albrecht  G. Di Baldassarre 《水文科学杂志》2020,65(Z3):12-20

ABSTRACT

What implications do societies’ risk perceptions have for flood losses? This study uses a stylized, socio-hydrological model to simulate the mutual feedbacks between human societies and flood events. It integrates hydrological modelling with cultural theory and proposes four ideal types of society that reflect existing dominant risk perception and management: risk neglecting, risk monitoring, risk downplaying and risk controlling societies. We explore the consequent trajectories of flood risk generated by the interactions between floods and people for these ideal types of society over time. The results suggest that flood losses are substantially reduced when awareness-raising attitudes are promoted through inclusive, participatory approaches in the community. In contrast, societies that rely on top-down hierarchies and structural measures to protect settlements on floodplains may still suffer significant losses during extreme events. This study illustrates how predictions formed through social science theories can be applied and tested in hydrological modelling.  相似文献   

Geospatial technologies for Chang’e-3 and Chang’e-4 lunar rover missions     

Kaichang Di  Zhaoqin Liu  Wenhui Wan  Man Peng  Bin Liu  Yexin Wang 《地球空间信息科学学报》2020,23(1):87-97

ABSTRACT

This paper presents a brief overview of the geospatial technologies developed and applied in Chang’e-3 and Chang’e-4 lunar rover missions. Photogrammetric mapping techniques were used to produce topographic products of the landing site with meter level resolution using orbital images before landing, and to produce centimeter-resolution topographic products in near real-time after landing. Visual positioning techniques were used to determine the locations of the two landers using descent images and orbital basemaps immediately after landing. During surface operations, visual-positioning-based rover localization was performed routinely at each waypoint using Navcam images. The topographic analysis and rover localization results directly supported waypoint-to-waypoint path planning, science target selection and scientific investigations. A GIS-based digital cartography system was also developed to support rover teleoperation.  相似文献   

Effects of trace metal and exposure to air on serotonin and dopamine levels in tissues of the mussel Perna perna   总被引：1，自引：0，他引：1  

Almeida EA  Bainy AC  Medeiros MH  Di Mascio P 《Marine pollution bulletin》2003,46(11):1485-1490

We evaluated levels of serotonin (5HT) and dopamine (DOPA) in muscle and digestive glands of the mussel, Perna perna, collected at different times of day; exposed to air for 24 h, followed by re-submersion; and after exposure to different metals. Mussels collected at different periods of day showed little oscillation in 5HT and DOPA levels. Mussels exposed to metals showed significant changes in 5HT and DOPA levels in digestive gland and muscle, as did mussels exposed to air. Our data suggest that analyses of 5HT and DOPA in tissues of mussels could serve as a tool to evaluate the presence and effects of heavy metal contamination in mussels. Care in data interpretation is required, however, since other environmental factors such as exposure of mussels to air (i.e. at low tides) can also cause changes in DOPA and 5HT levels. Additional research is necessary to separate such natural environmental effects from effects of contaminants.  相似文献   

The effect of chlorite interlayering on <Superscript>40</Superscript>Ar–<Superscript>39</Superscript>Ar biotite dating: an <Superscript>40</Superscript>Ar–<Superscript>39</Superscript>Ar laser-probe and TEM investigations of variably chloritised biotites     

Gianfranco?Di VincenzoEmail author  Cecilia?Viti  Sergio?Rocchi 《Contributions to Mineralogy and Petrology》2003,145(6):643-658

Biotite is one of the most common minerals dated by the ⁴⁰Ar–³⁹Ar method. It frequently shows K contents below the expected stoichiometric value, suggesting the presence of low-K impurities. The most common low-K alteration product of biotite is chlorite. Therefore, it is important to understand the effects of chlorite interlayering on ⁴⁰Ar–³⁹Ar ages in order to correctly interpret ⁴⁰Ar–³⁹Ar data. This study examines the outcome of ⁴⁰Ar–³⁹Ar dating analyses on variably chloritised biotites from Ordovician intrusive rocks. The infrared (IR) laser-probe technique and different gas extraction methods were adopted. Incremental laser-heating data on bulk samples yielded hump-shaped age profiles with meaningless young and old age steps. Both the extent of anomalous old age steps and the degree of discordance of the age spectra were much more pronounced in the more chloritised biotite samples. In contrast, in situ data on rock chips and total-fusion ages on single biotite flakes yielded ages concordant with, or younger than, the inferred emplacement ages. Transmission electron microscopy (TEM) was used to texturally characterise biotite samples at the nanometre scale. It was also used to document the complex decomposition-transformation process affecting interlayered biotite–chlorite during in-vacuo IR-laser heating to temperatures ranging from ~600 to >1,000 °C. TEM results suggest that hump-shaped age profiles result from an interplay between ³⁹Ar_K redistribution by recoil during sample irradiation and differential release of argon isotopes hosted in three main reservoirs. These reservoirs are (from least to most retentive): extended defects, chlorite and biotite. The final descending age segment is attributed to the progressive release of argon with increasing temperature from large biotite domains for which ³⁹Ar_K recoil loss was less important. ⁴⁰Ar–³⁹Ar data support previous findings, which suggest that ⁴⁰Ar–³⁹Ar ages when recoil effects are minimised, provide minimum estimates that approach the true biotite age, when the pristine domains are analysed. The most effective approach for obtaining meaningful ⁴⁰Ar–³⁹Ar ages was using individual total-fusion analyses on carefully selected, single flakes previously split along the basal cleavage by wet-grinding and corresponding to a sample mass of a few micrograms.Editorial responsibility: I Parsons  相似文献   

Natural contribution of harmful elements in thermal groundwaters of Ischia Island (southern Italy)     

A. Lima  D. Cicchella  S. Di Francia 《Environmental Geology》2003,43(8):930-940

Minor and trace element investigations have been performed on groundwaters of Ischia Island, which is located at the western edge of the bay of Naples. Ischia is formed entirely of Quaternary volcanic rocks. Intense seismicity, widespread fumaroles and thermal springs witness the persistent state of activity of its magmatic system. Groundwater samples, 58 from shallow thermal wells and 15 from thermal springs, were analysed for 72 elements by ICP-MS; temperature, pH and electrical conductivity (EC) were measured at the sampling site. Analytical data indicate clearly that the concentrations in the water of some elements, such as As, Be, Cu, Fe, Mn, Sb, Se and Tl, are often higher and sometimes much higher than the intervention limits fixed by the Italian Law DM 471 (25/10/1999) for water. Worthy of mention are the very high As values, reaching >1,000 µg/l in some wells. By means of R-mode factor analysis, 30 of 72 analysed elements were grouped as elemental associations representative of lithological type, water composition and, possibly, mineralization. Ischia thermal groundwaters are the result of mixing, in variable amounts, of deep magmatic fluids that are rich in metallic elements, with marine and/or meteoric waters. R-mode factor analysis and elemental association factor score distributions of the four-factor model confirm the existence of flux of magmatic mineralised fluids with marine and/or meteoric waters. Recharge by seawater intrusions occurs mostly in the north-western area of the island whereas the influence and control of magmatic mineralised fluids is clearly accentuated in the areas of Panza-Citara, Porto di Forio-Fango and Citara-Lido dei Maronti fracture alignments. The observed compositional variability of the analysed groundwaters, even in wells lying close to one another, is due to the local hydrodynamic conditions, controlled mostly by complex fault and fracture systems, which may represent preferential thermal water outflow routes. In general, the average minor and trace element compositions of Ischia thermal waters, when compared with the composition of sea and river water, show an enrichment in metallic elements such as As, Sc, V, Cr, Zn, Mo, U, W, Au, Hg. This paper points out that, in addition to the anthropogenic source, natural contribution also plays an important role in determining the high concentrations of toxic elements in groundwaters, which create health and acceptability problems.  相似文献   

Space-time soil wetness variations monitoring by a multi-temporal microwave satellite records analysis     

T. Lacava  E.V. Di Leo  V. Tramutoli 《Physics and Chemistry of the Earth》2006,31(18):1274-1283

In the last few years, remote sensing observations have become a useful tool for providing hydrological information, including the quantification of the main physical characteristics of the catchment, such as topography and land use, and of its variables, like soil moisture or snow cover. Moreover, satellite data have also been largely used in the framework of hydro-meteorological risk mitigation.Recently, an innovative Soil Wetness Variation Index (SWVI) has been proposed, using data acquired by the microwave radiometer AMSU (Advanced Microwave Sounding Unit) which flies aboard NOAA (National Oceanic and Atmospheric Administration) satellites.SWVI is based on a general approach for multi-temporal satellite data analysis (RAT - Robust AVHRR Techniques). This approach exploits the analysis of long-term multi-temporal satellite records in order to obtain a former characterization of the measured signal, in term of expected value and natural variability, providing a further identification of signal anomalies by an automatic, unsupervised change-detection step. Such an approach has already demonstrated, in several studies carried out on extreme flooding events which occurred in Europe in the past few years, its capability in reducing spurious effects generated by natural/observational noise. In this paper, the proposed approach is applied to the analysis of the flooding event which occurred in Europe (primarily in NW Spain) in June 2000. Results obtained, in terms of reliability as well as efficiency in space-time monitoring of soil wetness variation, are presented. Future prospects, in terms of exportability of the methodology on the new dedicated satellite missions, like ESA-SMOS and NASA-HYDROS, are also discussed.  相似文献   

水文资料在水土保持中的应用研究     

胡续礼  杨树江  吴迪  潘剑君 《水文》2006,26(5):45-47

本文简要分析了我国水文资料的基本特点及其在水土保持中的应用情况,并结合水文资料在水土保持中的研究实例,探讨了加强水文资料在水土保持中应用范围与价值,在新一轮的站网调整建设中应与水土保持监测站网建设结合起来,避免重复建设,加强水文站网功能,发挥现有水文站网作用。  相似文献   

Urban texture analysis with image processing techniques: winds and dispersion   总被引：1，自引：0，他引：1  

C. Ratti  S. Di Sabatino  R. Britter 《Theoretical and Applied Climatology》2006,84(1-3):77-90

Summary The focus is the analysis of urban Digital Elevation Models (DEMs) with image processing techniques. A brief review of existing methods to derive sky view factors, building energy consumption and space syntax shows how well established parameters that relate to airflow and dispersion (such as the height-to-width of urban canyons and the aerodynamic roughness length) can be calculated. Other measures of urban directionality and periodicity, inspired by traditional image processing, are also introduced, such as the Radon, Hough and Fourier transforms and the variance plot. Analyses of three case study sites in London, Toulouse and Berlin are compared, showing considerable variation in the chosen parameters. Results suggest that the DEM format is an extremely versatile tool to investigate the urban intermediate scale, allowing analyses that would be very difficult or impossible to carry out using traditional vectorial models.  相似文献   

Impact of increased vertical resolution on simulation of tropical climate   总被引：1，自引：0，他引：1  

P. M. Ruti  D. Di Rocco  S. Gualdi 《Theoretical and Applied Climatology》2006,85(1-2):61-80

Summary The aim of this study is to describe the behaviour of tropical dynamics in the ECHAM4 model when increased vertical resolution around the tropopause and in the planetary boundary layer is used. In this work we perform experiments with the ECHAM4 model using T30 horizontal resolution and 19 and 42 vertical levels. The impact of the increased vertical resolution on the simulation of tropical clouds and precipitation has been investigated. Therefore, the dynamic fields related to tropical convection have been analyzed. The results suggest a beneficial effect of the increased number of vertical levels on the convective scheme performance and on the related dynamic fields over the Tropics. The improvement of the rainfall climatologies in the 42-level model has been explained via the impact of vertical resolution on the cloud structure. In the cloud spectrum of the L42 simulation, a third peak appears around 600 hPa, revealing that when using higher vertical resolution the convective parametrization starts to represent cumulus congestus clouds.  相似文献