Predicting twenty-first century recession of architectural limestone in European cities     

Carlota M. Grossi  Alessandra Bonazza  Peter Brimblecombe  Ian Harris  Cristina Sabbioni 《Environmental Geology》2008,56(3-4):455-461

Cities of the twenty-first century will expose buildings to environments that are quite different from those experienced over preceding periods. The recent reduction in sulfur dioxide in cities and continued pressure to lower the emissions of combustion generated pollutants creates a potential for climate induced deterioration, by contrast, to be more important. Given that climate will likely change over the next hundred years, recession rates of calcareous stones have been predicted for Oviedo (Spain), Paris and Prague over the period 1981–2099. This can give guidance as to the likely change in balance of future threat. The Lipfert, ICP, and MULTI-ASSESS functions were used to calculate recession from estimates of climate and air quality. It is likely that under a continued decline or stable levels of pollution, recession rates having reached low values will remain largely unchanged over the coming century, despite likely changes in climate. Although the functions adopted disagree in a quantitative sense, there is evidence that they were reasonably concordant in the last decades of the twentieth century. In a cleaner future their different underlying assumptions lead to poorer agreement.  相似文献   

Evaluating the effects of protection on two benthic habitats at Tavolara-Punta Coda Cavallo MPA (North-East Sardinia, Italy)     

Ceccherelli G  Casu D  Pala D  Pinna S  Sechi N 《Marine environmental research》2006,61(2):171-185

In this paper, two benthic habitats have been investigated in a fully protected site and two control sites at the Tavolara-Punta Coda Cavallo marine protected area (MPA) (NE Sardinia). Overall, a protection effect on the benthic assemblages was highlighted in the shallow subtidal (5 m deep) rather than at intertidal algal turf habitat. Structure of assemblages at the shallow subtidal habitat is different in the fully protected site vs. controls, while this was not true for the intertidal habitat. At the subtidal, this finding is probably linked to indirect effects due to an increase of consumers in the protected site (e.g., sea urchins), while the lack of direct impacts in the intertidal at control sites is indicative of very similar assemblages. Cover of encrusting algae was significantly higher at the subtidal protected site suggesting a possible higher grazing pressure. Possible causes underlying the inconsistency of results obtained between habitats include the possibility that trophic cascade effects have a different influence at different heights on the shore. The need to estimate the interconnection among benthic habitats through trophic links is also highlighted to provide an estimate of the vulnerability to protection of various habitats.  相似文献   

Trajectory analysis at intersections for traffic rule identification     

Chenxi Wang  Stefania Zourlidou  Jens Golze  Monika Sester 《地球空间信息科学学报》2021,24(1):75-84

In this paper,we focus on trajectories at intersections regulated by various regulation types such as traffic lights,priority/yield signs,and right-of-way rules.We test some methods to detect and recognize movement patterns from GPS trajectories,in terms of their geometrical and spatio-temporal components.In particular,we first find out the main paths that vehicles follow at such locations.We then investigate the way that vehicles follow these geometric paths(how do they move along them).For these scopes,machine learning methods are used and the performance of some known methods for trajectory similarity measurement(DTW,Hausdorff,and Fréchet distance)and clustering(Affinity propagation and Agglomerative clustering)are compared based on clustering accuracy.Afterward,the movement behavior observed at six different intersections is analyzed by identifying certain movement patterns in the speed-and time-profiles of trajectories.We show that depending on the regulation type,different movement patterns are observed at intersections.This finding can be useful for intersection categorization according to traffic regulations.The practicality of automatically identifying traffic rules from GPS tracks is the enrichment of modern maps with additional navigation-related information(traffic signs,traffic lights,etc.).  相似文献   

Zonal jets and cyclone–anticyclone asymmetry in decaying rotating turbulence: laboratory experiments and numerical simulations     

Stefania Espa  Isabella Bordi  Thomas Frisius  Klaus Fraedrich  Antonio Cenedese  Alfonso Sutera 《地球物理与天体物理流体动力学》2013,107(6):557-573

The problem of zonal jet formation and cyclone–anticyclone asymmetry in decaying rotating turbulence is addressed using both laboratory experiments and numerical simulations with a high-resolution shallow water model in a spherical geometry. Experiments are performed at different Rossby and Froude numbers and applying a rigid wall as meridional boundary in the numerical scheme to mimic the experimental apparatus. The formation of a zonally banded flow pattern, i.e. meridionally confined easterly/westerly jets, has observed; both experimental and numerical results confirmed that this tendency is favoured by high-planetary vorticity gradients. Also, in the experiments characterized by large rotation speeds and small Rossby deformation radius, an initial symmetric distribution of relative vorticity is found to evolve towards a dominance of anticyclonic structures, indicating a breaking of the cyclone–anticyclone symmetry. This aspect has deepened by numerically analysing the sensitivity of the temporal variations of the asymmetry index with respect to the position of the meridional confinement as well as the effect of relaxing the divergence of the fluid (i.e. non-divergent case) to zero. Results suggested that experiments characterized by the higher rotation speed and the lower fluid thickness are better reproduced by a divergent model with a high-latitude meridional boundary.  相似文献   

Relative contribution of foliar and fine root pine litter to the molecular composition of soil organic matter after in situ degradation   总被引：1，自引：0，他引：1  

Stefania Mambelli  Jeffrey A. Bird  Gerd Gleixner  Todd E. Dawson  Margaret S. Torn 《Organic Geochemistry》2011,42(9):1099-1108

The influence of litter quality on soil organic matter (SOM) stabilization rate and pathways remains unclear. We used ¹³C/¹⁵N labeled litter addition and Curie-point pyrolysis gas chromatography–mass spectrometry combustion-isotope ratio mass spectrometry (Py–GC–MS–C–IRMS) to explore the transformation of litter with different composition and decay rate (ponderosa pine needle vs. fine root) to SOM during 18 months in a temperate conifer forest mineral (A horizon) soil. Based on ¹³C Py–GC–MS–C–IRMS the initial litter and bulk soil had ∼1/3 of the total pyrolysis products identified in common. The majority was related either to carbohydrates or was non-specific in origin. In bulk soil, carbohydrates had similar levels of enrichment after needle input and fine root input, while the non-specific products were more enriched after needle input. In the humin SOM fraction (260 yr C turnover time) we found only carbohydrate and alkyl C-derived compounds and greater ¹³C enrichment in the “carbohydrate” pool after fine root decomposition. ¹⁵N Py–GC–MS–C–IRMS of humic substances showed that root litter contributed more than needle litter to the enrichment of specific protein markers during initial decomposition.We found little evidence for the selective preservation of plant compounds considered to be recalcitrant. Our findings suggest an indirect role for decomposing plant material composition, where microbial alteration of fine root litter seems to favor greater initial stabilization of microbially derived C and N in SOM fractions with long mean turnover times, such as humin, compared to needles with a faster decay rate.  相似文献   

Risk assessment of Tunguska-type airbursts   总被引：1，自引：1，他引：0  

Arnaud Mignan  Patricia Grossi  Robert Muir-Wood 《Natural Hazards》2011,56(3):869-880

The Tunguska airburst, which devastated a taiga forest over an area greater than 2,000 km² in a remote region of Central Siberia in 1908, is a classic example of extraterrestrial encounter discussed in the asteroid/comet impact hazard and risk assessment literature (e.g. Longo 2007; Carusi et al. 2007). Although it is generally agreed that the cosmic body caused damage by bursting in the air rather than through direct impact on the Earth’s surface, the Tunguska event is often referred to as an impact event. To the best of our knowledge, no detailed studies have been performed to quantify the risk of a similar-sized event over a populated region. We propose here a straightforward probabilistic risk model for Tunguska-type events over the continental United States and use established risk metrics to determine the property (buildings and contents) and human losses. We find an annual average property loss of ~USD 200,000/year, a rate of ~0.3 fatalities/year and ~1.0 injuries/year ranging from a factor 3 below and to a factor 3 above the indicated values when a reasonable rate uncertainty for Tunguska-type events is taken into account. We then illustrate the case of an extreme event over the New York metropolitan area. While we estimate that this “nightmare” scenario would lead to ~USD 1.5 trillion of property loss, ~3.9 millions of fatalities and ~4.7 millions of injuries, such event is almost impossible (occurrence once every ~30 million years) and should only be considered as an illustrative example.  相似文献   

One Year of Surface-Based Temperature Inversions at Dome C, Antarctica     

Ilaria Pietroni  Stefania Argentini  Igor Petenko 《Boundary-Layer Meteorology》2014,150(1):131-151

In 2005 the Study of Stable Boundary Layer Environment at Dome C (STABLEDC) experimental campaign was conducted at the plateau station of Concordia at Dome C, Antarctica. Temperature profiles measured with a microwave radiometer were used to study the characteristics of surface-based temperature inversions over the course of a year. Statistics of temperature profiles for every month are discussed; the difference between daytime and nocturnal cases observed during the summer months disappears during winter. Surface-based temperature inversions occurred in 70 % of the time during summer, and almost all of the time during winter. During winter the occurrence of warming events leads to a decrease in the temperature difference between the top and the base of the inversion (i.e. the inversion strength). The inversion strength maxima ranged between $3\,^{\circ }\mathrm{C}$ (December) and $35\,^{\circ }\mathrm{C}$ (August) corresponding to gradients of 0.1 and $0.3\,^{\circ }\mathrm{C}\, \mathrm{m}^{-1}$ , respectively. The average surface-based inversion height presents a daily cycle during the summer months with values up to 200 m in the morning hours, while it affects a layer always deeper than 100 m during the winter months. The relationships between inversion strength and the downward longwave radiative flux, absolute temperature, and wind speed are examined. The inversion strength decreases as the longwave radiation increases. A clear anti-correlation between inversion strength and near-surface temperature is evident throughout the year. During the winter, the largest inversion strength values were observed under low wind-speed conditions; in contrast, a clear dependence was not found during the summer.  相似文献   

Erratum to: Observed and Modelled Convective Mixing-Layer Height at Dome C,Antarctica     

Giampietro Casasanta  Ilaria Pietroni  Igor Petenko  Stefania Argentini 《Boundary-Layer Meteorology》2014,153(1):163-164

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Evolution of massive haloes in non-Gaussian scenarios     

M. Grossi  K. Dolag  E. Branchini  S. Matarrese  L. Moscardini 《Monthly notices of the Royal Astronomical Society》2007,382(3):1261-1267

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Ecotoxicological and human health risk in a petrochemical district of southern Italy   总被引：2，自引：0，他引：2  

Ausili A  Gabellini M  Cammarata G  Fattorini D  Benedetti M  Pisanelli B  Gorbi S  Regoli F 《Marine environmental research》2008,66(1):215-217

An ecotoxicological investigation has been carried in the petrochemical district of Priolo (Sicily, Italy), one of the largest in Europe. Results indicated a severe mercury contamination in sediments sampled near a chloro-alkali plant. A clear bioavailability of this element was demonstrated in mussels Mytilus galloprovincialis (both native and translocated) and the benthic fish Mullus barbatus, which also exhibited marked genotoxic damages. The elevated mercury concentrations in marine organisms are a serious concern for human health; according to the national average fish consumption, the provisional tolerable weekly intake (PTWI) of Hg would be easily exceeded by at least 4 to 12 fold. Such toxicological risk is of particular importance for pregnant women, being possibly involved in the elevated frequency of neonatal malformations.  相似文献