bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimentally measured morphology of biomass burning aerosol and its impacts on CCN ability
Authors: Giordano M. , Espinoza C. , Asa-Awuku A.
Published: February 2015

Abstract. This study examines the morphological properties of freshly emitted and atmospherically aged aerosols from biomass burning. The impacts of particle morphology assumptions on hygroscopic predictions are examined. Chamber experiments were conducted at the University of California, Riverside, Center for Environmental Research and Technology (CE-CERT) atmospheric processes lab using two biomass fuel sources: manzanita and chamise. Morphological data was obtained through the use of an aerosol particle mass analyzer (APM), scanning mobility particle sizer (SMPS) system and transmission electron microscope (TEM). Data from these instruments was used to calculate both a dynamic shape factor and a fractal-like dimension for the biomass burning emissions. This data was then used with κ-Köhler theory to adjust the calculated hygroscopicity for experimentally determined morphological characteristics of the aerosol. Laboratory measurement of biomass burning aerosol from two chaparral fuels show that particles are nonspherical with dynamic shape factors greater than 1.15 for aerosol sizes relevant to cloud condensation nuclei (CCN) activation. Accounting for particle morphology can shift the hygroscopicity parameter by 0.15 or more. To our knowledge, this work provides the first laboratory chamber measurements of morphological characteristics for biomass burning cloud condensation nuclei and provides experimental particle shape evidence to support the variation in reported hygroscopicities of the complex aerosol.
Mixing state of carbonaceous aerosol in an urban environment: single particle characterization using the soot particle aerosol mass spectrometer (SP-AMS)
Authors: Lee A. K. Y. , Willis M. D. , Healy R. M. , Onasch T. B. , Abbatt J. P. D.
Published: February 2015

Abstract. Understanding the impact of atmospheric black carbon (BC)-containing particles on human health and radiative forcing requires knowledge of the mixing state of BC, including the characteristics of the materials with which it is internally mixed. In this study, we examine the mixing state of refractory BC (rBC) and other aerosol components in an urban environment (downtown Toronto) utilizing the Aerodyne soot particle aerosol mass spectrometer equipped with a light scattering module (LS-SP-AMS). k-means cluster analysis was used to classify single particle mass spectra into chemically distinct groups. One resultant particle class is dominated by rBC mass spectral signals (C1+ to C5+) while the organic signals fall into a few major particle classes identified as hydrocarbon-like organic aerosol (HOA), oxygenated organic aerosol (OOA), and cooking emission organic aerosol (COA). A gradual mixing is observed with small rBC particles only thinly coated by HOA (~ 28% by mass on average), while over 90% of the HOA-rich particles did not contain detectable amounts of rBC. Most of the particles classified into other inorganic and organic particle classes were not significantly associated with rBC. The single particle results also suggest that HOA and COA emitted from anthropogenic sources were likely major contributors to organic-rich particles with vacuum aerodynamic diameter (dva) ranging from ~ 200 to 400 nm. The similar temporal profiles and mass spectral features of the organic classes identified by cluster analysis and the factors from a positive matrix factorization (PMF) analysis of the ensemble aerosol data set validate the interpretation of the PMF results.
Increasing Arabian dust activity and the Indian Summer Monsoon
Authors: Solmon F. , Nair V. S. , Mallet M.
Published: February 2015

Abstract. Over the past decade, Aerosol Optical Depth (AOD) observations based on satellite and ground measurements have shown a significant increase over Arabia and the Arabian Sea, attributed to an intensification of regional dust activity. Recent studies have also suggested that west Asian dust forcing could induce a positive response of Indian monsoon precipitations on a weekly time scale. Using observations and a regional climate model including interactive slab ocean and dust aerosol schemes, the present study investigates possible climatic links between the increasing June-July-August-September (JJAS) Arabian dust activity and precipitation trends over southern India during the 2000–2009 decade. Meteorological reanalysis and AOD observations suggest that the observed decadal increase of dust activity and a simultaneous intensification of summer precipitation trend over southern India are both linked to a deepening of JJAS surface pressure conditions over the Arabian Sea. We show that the model skills in reproducing this trends and patterns are significantly improved only when an increasing dust emission trend is imposed on the basis of observations. We conclude that although climate variability might primarily determine the observed regional pattern of increasing dust activity and precipitation during the 2000–2009 decade, the associated dust radiative forcing might however induce a critical dynamical feedback contributing to enhanced regional moisture convergence and JJAS precipitation over Southern India.
Tropospheric aerosol profile information from high-resolution oxygen A-band measurements from space
Authors: Geddes A. , Bösch H.
Published: February 2015

Abstract. Aerosols are an important factor in the Earth climatic system and they play a key role in air quality and public health. Observations of the oxygen A-band at 760 nm can provide information on the vertical distribution of aerosols from passive satellite sensors that can be of great interest for operational monitoring applications with high spatial coverage if the aerosol information is obtained with sufficient precision, accuracy and vertical resolution. To address this issue, retrieval simulations of the aerosol vertical profile retrieval from O2 A-band observations by GOSAT, the upcoming Orbiting Carbon Observatory-2 (OCO-2) and Sentinel 5-P missions, and the proposed CarbonSat mission have been carried out. Precise retrievals of aerosol optical depth (AOD) within the boundary layer were found to favour low-resolution, high signal-to-noise instruments such as Sentinel-5 P, whereas higher-resolution instruments such as OCO-2 showed greater performance at higher altitudes and in information content above the boundary layer. Retrieval of the AOD in the 0–2 km range with precision appears difficult from all studied instruments and the retrieval errors typically exceed a value of 0.05 for AODs up to 0.3. Constraining the surface albedo is a promising and effective way of improving the retrieval of aerosol, but the accuracy of the required prior knowledge is very high. Due to the limited information content of the aerosol profile retrieval, the use of a parameterised aerosol distribution is assessed, and we show that the AOD and height of an aerosol layer can be retrieved well if the aerosol layer is uplifted to the free troposphere; however, errors are often large for aerosol layers in the boundary layer. Additional errors are introduced by incorrect assumptions on surface pressure and aerosol mixture, which can both bias retrieved AOD and height by up to 45%. In addition, assumptions of the boundary layer temperature are found to yield an additional error of up to 8%. We conclude that the aerosol profile retrievals from O2 A-band using existing or upcoming satellite sensors will only provide limited information on aerosols in the boundary layer but such observations can be of great value for observing and mapping aerosol plumes in the free troposphere.
Carbon dioxide flux and net primary production of a boreal treed bog: Responses to warming and water-table-lowering simulations of climate change
Authors: Munir T. M. , Perkins M. , Kaing E. , Strack M.
Published: February 2015

Abstract. Midlatitude treed bogs represent significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites: control, recent (1–3 years; experimental) and older drained (10–13 years), with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and estimated tree root respiration (Rr; across hummock–hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011–2013. The CO2–C balance was calculated by adding the net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to the driest and the warmest 2013, the control site was a CO2–C sink of 92, 70 and 76 g m−2, the experimental site was a CO2–C source of 14, 57 and 135 g m−2, and the drained site was a progressively smaller source of 26, 23 and 13 g CO2–C m−2. The short-term drainage at the experimental site resulted in small changes in vegetation coverage and large net CO2 emissions at the microforms. In contrast, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) on the hummocks and lichen in the hollows leading to the highest CO2 uptake at the drained hummocks and significant losses in the hollows. The tree NPP (including above- and below-ground growth and litter fall) in 2011 and 2012 was significantly higher at the drained site (92 and 83 g C m−2) than at the experimental (58 and 55 g C m−2) and control (52 and 46 g C m−2) sites. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ~ 1 °C and differential air warming of ~ 6 °C at midday full sun over the study years. Warming significantly enhanced shrub growth and the CO2 sink function of the drained hummocks (exceeding the cumulative respiration losses in hollows induced by the lowered water level × warming). There was an interaction of water level with warming across hummocks that resulted in the largest net CO2 uptake at the warmed drained hummocks. Thus in 2013, the warming treatment enhanced the sink function of the control site by 13 g m−2, reduced the source function of the experimental by 10 g m−2 and significantly enhanced the sink function of the drained site by 73 g m−2. Therefore, drying and warming in continental bogs is expected to initially accelerate CO2–C losses via ecosystem respiration, but persistent drought and warming is expected to restore the peatland's original CO2–C sink function as a result of the shifts in vegetation composition and productivity between the microforms and increased NPP of trees over time.
Sources and transfer mechanisms of dissolved organic matter during storm and inter-storm conditions in a lowland headwater catchment: constraints from high-frequency molecular data
Authors: Jeanneau L. , Denis M. , Pierson-Wickmann A.-C. , Gruau G. , Lambert T. , Petitjean P.
Published: February 2015

Abstract. The transfer of dissolved organic matter (DOM) at soil–river interfaces controls the biogeochemistry of micropollutants and the equilibrium between continental and oceanic C reservoirs. Then determining the transfer mechanisms of DOM is of main importance for ecological and geochemical reasons. Is stream DOM the result of the flushing of pre-existing soil DOM reservoirs activated by the modification of water flow paths? The evolution of the chemical composition of stream DOM investigated by thermally assisted hydrolysis and methylation (THM) using tetramethylammonium hydroxide (TMAH) coupled to a gas chromatograph and mass spectrometer (THM-GC-MS) during inter-storm conditions and five storm events with a high-frequency sampling gives new insights on this question. In inter-storm conditions, stream DOM is inherited from the flushing of soil DOM, while during storm events, the modification of the distribution of chemical biomarkers allows the identification of three additional mechanisms. The first one corresponds to the destabilization of microbial biofilms by the increase in water velocity resulting in the fleeting export of a microbial pool. The second mechanism corresponds to the erosion of soils and river banks leading to a partition of organic matter between particles and dissolved phase. The third mechanism is linked to the increase in water velocity in soils that could induce the erosion of macropore walls, leading to an in-soil partitioning between soil microparticles and dissolved phase. The contribution of this in-soil erosive process would be linked to the magnitude of the hydraulic gradient following the rise of water table and could persist after the recession, which could explain why the return to inter-storm composition of DOM does not follow the same temporal scheme as the discharge. Those results are of main importance to understand the transfer of nutrients and micropollutants at the soil–river interfaces during the hot moments that are storm events.
Representing northern peatland microtopography and hydrology within the Community Land Model
Authors: Shi X. , Thornton P. E. , Ricciuto D. M. , Hanson P. J. , Mao J. , Sebestyen S. D. , Griffiths N. A. , Bisht G.
Published: February 2015

Abstract. Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics in northern peatlands, and provides a useful foundation for investigation of northern peatland carbon exchange.
AROME-WMED, a real-time mesoscale model designed for the HyMeX Special Observation Periods
Authors: Fourrié N. , Bresson É. , Nuret M. , Jany C. , Brousseau P. , Doerenbecher A. , Kreitz M. , Nuissier O. , Sevault E. , Bénichou H. , Amodei M. , Pouponneau F.
Published: February 2015

Abstract. During autumn 2012 and winter 2013, two Special Observation Periods (SOPs) of the Hydrological cycle in the Mediterranean Experiment (HyMeX) took place. For the preparatory studies and to support the instrument deployment during the field campaign, a dedicated version of the operational convective-scale AROME-France model was developed: the AROME-WMED model. It covers the western Mediterranean basin with a 48 h forecast range. It provided real time analyses and forecasts which were sent daily to the HyMeX operational centre to forecast high precipitation events and to help decision makers on the deployment of observation instruments. This paper presents the main features of this numerical weather prediction system in terms of data assimilation and forecast. Some specific data of the HyMeX SOP were assimilated in real time. The forecast skill of the AROME-WMED is then assessed with objective scores and compared to the operational AROME-France model, for both autumn 2012 (5 September to 6 November 2012) and winter 2013 (1 February to 15 March 2013) SOPs. The overall performance of AROME-WMED is good and similar to those of AROME-France for the 0 to 30 h common forecast range. The 24 to 48 h forecast range is of course less accurate but remains useful for scheduling observation deployment. The characteristics of parameters such as precipitation, temperature or humidity, are illustrated by one heavy precipitation case study that occurred over the south of Spain.
Derivation of a new continuous adjustment function for correcting wind-induced loss of solid precipitation: results of a Norwegian field study
Authors: Wolff M. A. , Isaksen K. , Petersen-Øverleir A. , Ødemark K. , Reitan T. , Brækkan R.
Published: February 2015

Abstract. Precipitation measurements exhibit large cold-season biases due to under-catch in windy conditions. These uncertainties affect water balance calculations, snowpack monitoring and calibration of remote sensing algorithms and land surface models. More accurate data would improve the ability to predict future changes in water resources and mountain hazards in snow-dominated regions. In 2010, a comprehensive test site for precipitation measurements was established on a mountain plateau in southern Norway. Automatic precipitation gauge data are compared with data from a precipitation gauge in a Double Fence Intercomparison Reference (DFIR) wind shield construction which serves as the reference. A large number of other sensors are provided supporting data for relevant meteorological parameters. In this paper, data from three winters are used to study and determine the wind-induced under-catch of solid precipitation. Qualitative analyses and Bayesian statistics are used to evaluate and objectively choose the model that best describes the data. A continuous adjustment function and its uncertainty are derived for measurements of all types of winter precipitation (from rain to dry snow). A regression analysis does not reveal any significant misspecifications for the adjustment function, but shows that the chosen model does not describe the regression noise optimally. The adjustment function is operationally usable because it is based only on data available at standard automatic weather stations. The results show a non-linear relationship between under-catch and wind speed during winter precipitation events and there is a clear temperature dependency, mainly reflecting the precipitation type. The results allow, for the first time, derivation of an adjustment function based on measurements above 7 m s−1. This extended validity of the adjustment function shows a stabilization of the wind-induced precipitation loss for higher wind speeds.
Development and evaluation of an efficient soil-atmosphere model (FHAVeT) based on the Ross fast solution of the Richards equation for bare soil conditions
Authors: Tinet A.-J. , Chanzy A. , Braud I. , Crevoisier D. , Lafolie F.
Published: February 2015

Abstract. In agricultural management, a good timing in operations, such as irrigation or sowing, is essential to enhance both economical and environmental performance. To improve such timing, predictive software are of particular interest. Optimal decision-software would require process modules which provide robust, efficient and accurate predictions while being based on a minimal amount of parameters easily available. The objective of this study is to assess the accuracy of a physically based model with high efficiency. To this aim, this paper develops a coupled model with climatic forcing based on the Ross fast solution for Richards' equation, heat transfer and detailed surface energy balance. The present study is limited to bare soil, but the impact of vegetation can be easily included. The developed model, FHAVeT (Fast Hydro Atmosphere Vegetation Temperature), is evaluated against the coupled model based on the Philip and De Vries (1957) description, TEC. The two models were compared for different climatic and soil conditions. Moreover, the model allows using various pedotransfer functions. The FHAVeT model showed better performance in regards to mass balance, mostly below 0.002 m, and generally improved computation time. In order to allow for a more precise comparison, six time windows were selected. The study demonstrated that the FHAVeT behaviour is quite similar to the TEC behaviour except under some dry conditions. The ability of the models to detect the occurrence of soil intermediate water content thresholds with a 1 day tolerance was also evaluated. Both models agreed in more than 90% of the cases.
Spatially shifting temporal points: estimating pooled within-time series variograms for scarce hydrological data
Authors: Bhowmik A. K. , Cabral P.
Published: February 2015

Abstract. Estimation of pooled within-time series (PTS) variograms is a frequently used technique for geostatistical interpolation of continuous hydrological variables in spatial data-scarce regions conditional that time series are available. The only available method for estimating PTS variograms averages semivariances, which are computed for individual time steps, over each spatial lag within a pooled time series. However, semivariances computed by a few paired comparisons for individual time steps are erratic and hence they may hamper precision of PTS variogram estimation. Here, we outlined an alternative method for estimating PTS variograms by spatializing temporal data points and shifting them. The data were pooled by ensuring consistency of spatial structure and stationarity within a time series, while pooling sufficient number of data points for reliable variogram estimation. The pooled spatial data point sets from different time steps were assigned to different coordinate sets on the same space. Then a semivariance was computed for each spatial lag within a pooled time series by comparing all point pairs separable by that spatial lag, and a PTS variogram was estimated by controlling the lower and upper boundary of spatial lags. Our method showed higher precision than the available method for PTS variogram estimation and was developed by using the freely available R open source software environment. The method will reduce uncertainty for spatial variability modeling while preserving spatiotemporal properties of data for geostatistical interpolation of hydrological variables in spatial data-scarce developing countries.
A model of mudflow propagation downstream from the Grohovo landslide near the city of Rijeka (Croatia)
Authors: Žic E. , Arbanas Ž. , Bićanić N. , Ožanić N.
Published: February 2015

Abstract. Mudflows regularly generate significant human and property losses. Analyzing mudflows is important to assess the risks and to delimit vulnerable areas where mitigation measures are required. The smoothed-particle hydrodynamics (SPH) model adopted here considers, in two phases, a granular skeleton with voids filled with either water or mud. The SPH depth-integrated numerical model (Pastor et al., 2009a) used for the present simulations is a 2-D model capable of predicting the runout distance, flow velocity, deposition pattern and the final volume of mudflows. It is based on mathematical and rheological models. In this study, the main characteristics of mudflow processes that have emerged in the past (1908) in the area downstream of the Grohovo landslide are examined, and the more relevant parameters and attributes describing the mudflow are presented. Principal equations that form the basis of the SPH depth-integrated model are reviewed and applied to analyze the Grohovo landslide and the propagation of the mudflow wave downstream of the landslide. Based on the SPH method, the runout distance, quantities of the deposited materials and the velocity of mudflow progression which occurred in the past at the observed area are analyzed and qualitatively compared to the recorded consequences of the actual event. Within the SPH simulation, the Newtonian rheological model in the turbulent flow regime and the Bingham rheological model were adopted and a comparison was made of the application of the Egashira and Hungr erosion law.
Earthquake sequencing: Chimera states with Kuramoto model dynamics on directed graphs
Authors: Vasudevan K. , Cavers M. , Ware A.
Published: February 2015

Abstract. Earthquake sequencing studies allow us to investigate empirical relationships among spatio-temporal parameters describing the complexity of earthquake properties. We have recently studied the relevance of Markov chain models to draw information from global earthquake catalogues. In these studies, we considered directed graphs as graph theoretic representations of the Markov chain model, and analyzed their properties. Here, we look at earthquake sequencing itself as a directed graph. In general, earthquakes are occurrences resulting from significant stress-interactions among faults. As a result, stress-field fluctuations evolve continuously. We propose that they are akin to the dynamics of the collective behaviour of weakly-coupled non-linear oscillators. Since mapping of global stress-field fluctuations in real time at all scales is an impossible task, we consider an earthquake zone as a proxy for a collection of weakly-coupled oscillators, the dynamics of which would be appropriate for the ubiquitous Kuramoto model. In the present work, we apply the Kuramoto model to the non-linear dynamics on a directed graph of a sequence of earthquakes. For directed graphs with certain properties, the Kuramoto model yields synchronization, and inclusion of non-local effects evokes the occurrence of chimera states or the co-existence of synchronous and asynchronous behaviour of oscillators. In this paper, we show how we build the directed graphs derived from global seismicity data. Then, we present conditions under which chimera states could occur and subsequently, point out the role of Kuramoto model in understanding the evolution of synchronous and asynchronous regions.
Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands
Authors: Hedo J. , Lucas-Borja M. E. , Wic C. , Andrés-Abellán M. , de Las Heras J.
Published: February 2015

Abstract. Wildfires affecting forest ecosystems and post-fire silvicultural treatments may cause considerable changes in soil properties. The capacity of different microbial groups to recolonise soil after disturbances is crucial for proper soil functioning. The aim of this work was to investigate some microbial soil properties and enzyme activities in semiarid and dry Aleppo pine (Pinus halepensis M.) forest stands. Different plots affected by a wildfire event 17 years ago without or with post-fire silvicultural treatments 5 years after the fire event were selected. A mature Aleppo pine stand, unaffected by wildfire and not thinned was used as a control. Physicochemical soil properties (soil texture, pH, carbonates, organic matter, electrical conductivity, total N and P), soil enzymes (urease, phosphatase, β-glucosidase and dehydrogenase activities), soil respiration and soil microbial biomass carbon were analysed in the selected forests areas and plots. The main finding was that long time after this fire event produces no differences in the microbiological soil properties and enzyme activities of soil after comparing burned and thinned, burned and not thinned, and mature plots. Moreover, significant site variation was generally seen in soil enzyme activities and microbiological parameters. We conclude that total vegetation recovery normalises post-fire soil microbial parameters, and that wildfire and post-fire silvicultural treatments are not significant factors affecting soil properties after 17 years.
High-temperature metamorphism during extreme thinning of the continental crust: a reappraisal of the north Pyrenean paleo-passive margin
Authors: Clerc C. , Lahfid A. , Monié P. , Lagabrielle Y. , Chopin C. , Poujol M. , Boulvais P. , Ringenbach J.-C. , Masini E. , de St Blanquat M.
Published: February 2015

Abstract. An increasing number of field examples in mountain belts show that the formation of passive margins during extreme continent thinning may occur under conditions of high to very high thermal gradient beneath a thin cover of syn-rift sediments. Orogenic belts resulting from the tectonic inversion of distal margins and regions of exhumed continental mantle may exhibit high-temperature, low-pressure (HT-LP) metamorphism and coeval syn-extensional, ductile deformation. Recent studies have shown that the northern flank of the Pyrenean belt, especially the North Pyrenean Zone, is one of the best examples of such inverted hot, passive margin. In this study, we provide a map of HT-LP metamorphism based on a dataset of more than one hundred peak-temperature estimates obtained using Raman spectroscopy of the carbonaceous material (RSCM). This dataset is completed by previous PT estimates based on mineral assemblages, and new Ar–Ar (amphibole, micas) and U–Pb (titanite) ages from metamorphic and magmatic rocks of the North Pyrenean Zone. The implications on the geological evolution of the Cretaceous Pyrenean paleomargins are discussed. Ages range mainly from 110 to 90 Ma and no westward or eastward propagation of the metamorphism and magmatism can be clearly identified. In contrast, the new data reveal a progressive propagation of the thermal anomaly from the base to the surface of the continental crust. Focusing on the key-localities of the Mauléon Basin, Arguenos-Moncaup, Lherz, Boucheville and the Bas-Agly, we analyse the thermal conditions prevailing during the Cretaceous crustal thinning. The results are synthetized into a series of three regional thematic maps, and into two detailed maps of the Arguenos-Moncaup and Lherz areas. The results indicate a first-order control of the thermal gradient by the intensity of crustal thinning. The highest grades of metamorphism are intimately associated with the areas where subcontinental mantle rocks have been unroofed or exhumed.
Assessment of sea ice simulations in the CMIP5 models
Authors: Shu Q. , Song Z. , Qiao F.
Published: February 2015

Abstract. The historical simulations of sea ice during 1979 to 2005 by the Coupled Model Intercomparison Project Phase 5 (CMIP5) are compared with satellite observations, Global Ice-Ocean Modeling and Assimilation System (GIOMAS) output data and Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) output data in this study. Forty-nine models, almost all of the CMIP5 climate models and earth system models with historical simulation, are used. For the Antarctic, multi-model ensemble mean (MME) results can give good climatology of sea ice extent (SIE), but the linear trend is incorrect. The linear trend of satellite-observed Antarctic SIE is 1.29 (±0.57) × 105 km2 decade−1; only about 1/7 CMIP5 models show increasing trends, and the linear trend of CMIP5 MME is negative with the value of −3.36 (±0.15) × 105 km2 decade−1. For the Arctic, both climatology and linear trend are better reproduced. Sea ice volume (SIV) is also evaluated in this study, and this is a first attempt to evaluate the SIV in all CMIP5 models. Compared with the GIOMAS and PIOMAS data, the SIV values in both the Antarctic and the Arctic are too small, especially for the Antarctic in spring and winter. The GIOMAS Antarctic SIV in September is 19.1 × 103 km3, while the corresponding Antarctic SIV of CMIP5 MME is 13.0 × 103 km3 (almost 32% less). The Arctic SIV of CMIP5 in April is 27.1 × 103 km3, which is also less than that from PIOMAS SIV (29.5 × 103 km3). This means that the sea ice thickness simulated in CMIP5 is too thin, although the SIE is fairly well simulated.
Microscale variability of snow depth using U.A.S. technology
Authors: De Michele C. , Avanzi F. , Passoni D. , Barzaghi R. , Pinto L. , Dosso P. , Ghezzi A. , Gianatti R. , Della Vedova G.
Published: February 2015

Abstract. We investigate the capabilities of photogrammetry-based surveys with Unmanned Aerial Systems (U.A.S.) to retrieve the snow depth distribution at cm resolution over a small alpine area (~300 000 m2). For this purpose, we have designed two field campaigns during the 2013/2014 winter season. In the first survey, realized at the beginning of the accumulation season, the digital elevation model of bare soil has been obtained. The second survey, made at the end of the accumulation season, allowed to determine the snow depth distribution as difference with respect to the previous aerial survey. 12 manual measurements of snow depth were collected at random positions in order to run a point comparison with U.A.S. measurements. The spatial integration of U.A.S. snow depth measurements allowed to estimate the snow volume accumulated over the area. We compare this volume estimation with the ones provided by classical interpolation techniques of the 12 point measurements. Results show that the U.A.S. technique provides an accurate estimation of point snow depth values (the average difference with reference to manual measurements is of −7.3 cm), and a distributed evaluation of the snow accumulation patterns. Moreover, the interpolation techniques considered return average differences in snow volume estimation, with respect to the one obtained through the U.A.S. technology, equal to ~21%.
The Relationship between Gold Prices and Exchange Value of US Dollar in India
Authors: Nair Girish Karunakaran , Choudhary Nidhi , Purohit Harsh
Published: February 2015

The inverse relationship between the value of U.S. dollar and that of gold is one of the most talked about relationships in currency markets. The present study is an attempt to understand the impact of recession of 2008 on relationship between exchange rate of US dollar in INR and gold prices in India. The study uses Johansen Co- Integration test to check the long term association between exchange rate of US dollar in INR and gold prices in India and it further uses the Granger Causality Test to check the lead lag relationship between the variables. A separate pre, during and post recession analysis of the variables is done to understand the impact of recession on this relationship. The study highlights how this relationship has changed since the global turmoil.
The Participation Banking As A Distinctive Method And The Its Growing In The Turkish Finance Market-Period: 2007-2013
Authors: Sayım Ferhat
Published: February 2015

Financial systems and companies has become the most important reason in the weakness of world economic system. The formation and development process of the financial structure also constitutes the infrastructure of the world economic system. The path of the financial system and development has led to discuss with the financial crisis in 2008-2011. One of the argument topic in order to reduce problems caused by the conventional banking system is alternative financing systems. In Turkey, the corporations based on profit share system which are named participation based banking attention, if the alternative banking systems are considered. These banks which settle on different principles in the risk distribution of the portfolio acquired are analyzed more nowadays. Participation based banks are placed in almost every regulation related to banking terms and get their legal infrastructure more stable in the banking legislation of Turkey.This study is a 2007-2013 part of research series. We try to find out the place and the importance of participation based banking with the various sub-headings especially in Turkey. We examine the comparative review 2007-2013 data of participation banks which Total Assets, Equity Net Profit, Collected Turkish Currency and Foreign Currency Funds and Bank Loan Funds, figures for the four participation banks in Turkey. We are comparing the total figures with deposit banks for the same period.One of our primary aim in this essay, to study in the framework of the alternatives of the financial companies and options. These options could be stated as a vibrant and viable well established choice as a non-western model- different from the classical western interest based leading banking system in the globe. Moreover, that participation banking systems’ grow and increase with its resourceful bulk of transactions and shares within the financial market. In addition, we intended to delineate the basic functioning structures, rules, norms, principles, procedures, operations of that alternate banking system in the financial market.
Canine Alopecia Secondary to Human Topical Hormone Replacement Therapy in Six Dogs
Authors: Berger Darren J. , Lewis Thomas P. , Schick Anthea E. , Miller Rose I. , Loeffler Diana G.
Published: February 2015

Alopecia is a common presenting complaint in veterinary medicine and is known to occur secondary to numerous primary conditions. In this report, six unrelated dogs from three households were subsequently determined to have developed alopecia as a result of accidental transdermal exposure to their owners' topical hormone replacement therapy (THRT). All cases presented with alopecia ranging in duration from 2 mo to 2.5 yr. All dogs demonstrated alopecia affecting the ventral neck, thoracic and abdominal surfaces, proximal lateral extremities, and lateral trunk. At the time of initial presentation, five of six dogs were also noted to have physical exam findings suggestive of feminization. In all cases, serum total thyroxine was within normal reference range. Affected skin was biopsied in five dogs, and all samples demonstrated four similar histological characteristics: basal melanosis, epidermal and infundibular follicular hyperkeratosis, kenogen hair follicles, and small sebaceous glands. All dogs had elevated baseline estradiol levels, and four dogs had concurrent elevations of baseline progesterone. Average time to onset of clinical signs in those dogs was 5.5 mo after the owners started THRT. Following discontinuation of THRT by the owners, all dogs had complete resolution of their clinical signs by 5.5 mo.
Influence of Growth Parameters on the Formation of Hydroxyapatite (HAp) Nanostructures and Their Cell Viability Studies
Authors: Manoj Murugesan , Subbiah Ramesh , Mangalaraj Devanesan , Ponpandian Nagamony , Viswanathan Chinnuswamy , Park Kwideok
Published: February 2015

Morphology controlled hydroxyapatite (HAp) nanostructures play a vital role in biomedical engineering, tissue regenerative medicine, biosensors, chemotherapeutic applications, environmental remediation, etc. The present work investigates the influence of temperature, pH and time on the growth of HAp nanostructures using a simple, cost effective and surfactant free chemical approach. The obtained HAp nanostructures were systematically investigated by analytical techniques such as XRD, FESEM, EDX, FTIR and Raman spectroscopy. The XRD analysis showed that the hexagonal structure of the hydroxyapatite and average crystallite size was estimated from this analysis. The electron microscopic analysis confirmed the different morphologies obtained by varying the synthesis parameters such as temperature, pH and time. The elemental composition was determined through EDS analysis. FTIR and Raman spectroscopic analysis confirmed the presence of functional groups and the purity and crystallinity of the samples. The biocompatibility and adhesion nature of samples was examined with mouse preosteoblast cells. The obtained results demonstrated good biocompatibility and excellent focal adhesion.
Les transformations et défis actuels de la formation générale des adultes
Authors: Voyer Brigitte , Potvin Maryse , Bourdon Sylvain
Published: February 2015

Ce texte présente une introduction aux transformations et défis qui se posent actuellement à la formation générale des adultes au Québec, un secteur éducatif qui vise à rendre accessible la formation de base pour tous. Il décrit les principaux facteurs sociaux, démographiques, culturels et économiques qui participent à des changements importants dans l’organisation, l’offre et la prestation de services d’éducation, de formation et d’accompagnement. Les auteurs soulignent notamment les défis posés par l’émergence de nouveaux profils d’apprenants adultes, l’instauration d’un nouveau curriculum et la mise en oeuvre de dispositifs de reconnaissance des acquis. Les auteurs rappellent plusieurs études qui font écho à ces changements, tout en soulignant que la recherche menée dans ce domaine néglige certaines problématiques. En conclusion, les auteurs constatent que l’évolution observée n’est pas strictement de l’ordre du changement ou de l’adaptation, mais plutôt de l’ordre d’une transformation systémique qui tend à modifier la mission première de la formation de base.
La diversité et la complexité des jeunes (16-24 ans) inscrits à l’éducation des adultes au Québec : enquête et essai de typologie
Authors: Marcotte Julie , Villatte Aude , Lévesque Geneviève
Published: February 2015

Au Québec, les dispositifs institutionnels en éducation des adultes jouent un rôle majeur dans la qualification des jeunes qui quittent l’école secondaire sans avoir obtenu leur diplôme. L’accroissement de l’effectif 16-24 ans et, surtout, l’hétérogénéité de ce groupe sur le plan de leurs caractéristiques et de leurs besoins se positionnent parmi les défis contemporains auxquels est confrontée la formation générale des adultes. Cet article présente une recherche réalisée auprès de 386 jeunes âgés de 16 à 24 ans qui fréquentent un centre d’éducation des adultes au Québec. Notre étude propose une analyse de classes latentes qui permet de fragmenter l’hétérogénéité des jeunes en quatre profils types. Cette méthode statistique a donc permis de dégager une typologie dont les caractéristiques distinctives reflètent tantôt les enjeux actuels inhérents au passage à l’âge adulte, tantôt les empreintes consécutives à une trajectoire de vie fragilisante. Finalement, les éléments de discussion mettent en relief les besoins respectifs de ces quatre profils en matière de services complémentaires.
Formation des enseignants du secteur de l’éducation des adultes à l’évaluation des compétences : défis et perspectives
Authors: Nizet Isabelle
Published: February 2015

La réforme du curriculum de la Formation générale des adultes réactive la question de la professionnalisation des enseignants de ce secteur par le biais de leur formation initiale et continue. Une recherche exploratoire a été entreprise pour repérer comment est prise en compte la réalité professionnelle de ces enseignants dans la construction de savoirs professionnels en évaluation. La méthodologie est fondée sur l’analyse de contenu de documents référentiels et d’artefacts réflexifs produits par des enseignants du secteur des adultes en formation qualifiante en ligne. Les résultats montrent que les situations professionnelles et le contexte professionnel propres à ce secteur façonnent une culture évaluative particulière qui rend la construction de savoirs professionnels possible, mais leur transposition dans les situations de travail aléatoire. Ces constats mettent en lumière les besoins de formation spécifiques aux enseignants de ce secteur et les enjeux de l’intégration des situations professionnelles dans une formation qualifiante à l’évaluation.
La reconnaissance des acquis en formation générale des adultes : quelques enjeux de mise en oeuvre du dispositif Univers de compétences génériques
Authors: Bélisle Rachel , Michaud Guylaine , Bourdon Sylvain , Rioux Isabelle
Published: February 2015

L’objectif de cet article est de mieux comprendre les enjeux politiques et pragmatiques de la reconnaissance des acquis expérientiels en formation générale, à partir des Univers de compétences génériques, un dispositif québécois récent, et de dégager des défis que celui-ci pose au système éducatif. Les résultats sont issus d’entrevues auprès d’adultes ayant obtenu une reconnaissance officielle au niveau secondaire (n = 13) et d’intervenantes (n = 5) de deux commissions scolaires. Les enjeux documentés relèvent de l’accès à l’information, ainsi que du travail d’identification et d’évaluation des acquis. Ce dispositif pose d’importants défis, dont celui d’une mise en oeuvre cohérente avec la perspective d’apprentissage tout au long de la vie.
La formation générale des adultes non bacheliers à l’université : déterminants de l’engagement et de la persévérance
Authors: Zaouani-Denoux Souâd
Published: February 2015

Cet article présente une recherche exploratoire visant à connaître certaines caractéristiques et le profil des inscrits à la préparation au diplôme d’accès aux études universitaires et à identifier les motivations qui président à leur engagement dans ce processus. Nous y examinerons aussi la contribution de certains facteurs à l’explication de leur persévérance ou abandon. Les données proviennent de 24 entrevues semi-dirigées et de trois corpus de données quantitatives. Les résultats montrent que la motivation et l’engagement relèvent de motifs intrinsèques et extrinsèques. Ils montrent aussi que le maintien et l’abandon sont des phénomènes très complexes liés à plusieurs facteurs. Des pistes de réflexion et d’action pertinentes visant à favoriser l’engagement, le maintien et la réussite, à considérer par les universités préparant à ce diplôme, sont également examinées.
Quelle place pour les méthodes mixtes dans la recherche francophone en management ?
Authors: Aldebert Bénédicte , Rouzies Audrey
Published: February 2015

Cette note de recherche analyse l’utilisation des méthodes mixtes dans la recherche francophone en management. Une étude bibliographique de trois supports (AIMS, M@n@gement, Management International) a été réalisée. L’analyse des 2341 articles permet de conclure que le recours aux méthodes mixtes demeure limité. La contribution majeure de cet article est de montrer que les méthodes mixtes permettent d’enrichir le design de recherche soit en amont (enrichissement du questionnement) soit en aval (enrichissement des résultats) soit aux deux niveaux (amont et aval). Cette note de recherche permettra également aux chercheurs de comprendre l’intérêt et les possibles opérationnalisations des méthodes mixtes.
Gouvernance et dynamiques d’innovation au sein d’un technopôle. Une analyse par les pratiques institutionnelles d’innovation
Authors: Berthinier-Poncet Anne
Published: February 2015

Notre recherche vise à identifier le rôle de la gouvernance d’un technopôle pour créer un environnement propice à l’innovation des entreprises. Nous prolongeons les travaux récents sur la gouvernance des clusters en mobilisant le concept de travail institutionnel pour préciser les leviers (politique, normatif et cognitif) et les pratiques mis en oeuvre par la structure de gouvernance afin de stimuler l’innovation à l’échelle collective. Nos résultats, basés sur l’étude du cas Savoie Technolac, montrent que la faible mobilisation des pratiques politiques et normatives freine la construction de la légitimité du technopôle quand l’accent porté aux pratiques cognitives influence positivement la dynamique d’apprentissage et d’innovation.
Le rôle de la responsabilité sociale dans la connaissance organisationnelle : approche conceptuelle
Authors: Barraquier Anne
Published: February 2015

Cet article suggère tout d’abord que les processus de responsabilité sociale ont la capacité, comme d’autres processus, de créer de la connaissance. Puis, il développe l’idée selon laquelle ces processus, en questionnant l’objet (faire du profit) et les valeurs de l’organisation, la poussent à produire des connaissances qui modifient son activité, son modèle économique et sa stratégie d’innovation. La contribution théorique permet de renforcer l’ancrage de la responsabilité sociale dans la théorie des ressources.