bluuebunny/crossref_metadata_2025 huggingface dataset:
Coal fly ash: linking immersion freezing behavior and physicochemical particle properties
Authors: Grawe Sarah , Augustin-Bauditz Stefanie , Clemen Hans-Christian , Ebert Martin , Eriksen Hammer Stine , Lubitz Jasmin , Reicher Naama , Rudich Yinon , Schneider Johannes , Staacke Robert , Stratmann Frank , Welti André , Wex Heike
Published: October 2018

Abstract. To date, only a few studies have investigated the
potential of coal fly ash particles to trigger heterogeneous ice nucleation
in cloud droplets. The presented measurements aim at expanding the sparse
dataset and improving process understanding of how physicochemical particle
properties can influence the freezing behavior of coal fly ash particles
immersed in water. Firstly, immersion freezing measurements were performed with two single
particle techniques, i.e., the Leipzig Aerosol Cloud Interaction Simulator
(LACIS) and the SPectrometer for Ice Nuclei (SPIN). The effect of suspension
time on the efficiency of the coal fly ash particles when immersed in a cloud
droplet is analyzed based on the different residence times of the two
instruments and employing both dry and wet particle
generation. Secondly, two
cold-stage setups, one using microliter sized droplets (Leipzig Ice
Nucleation Array) and one using nanoliter sized droplets (WeIzmann
Supercooled Droplets Observation on Microarray setup) were applied. We found that coal fly ash particles are comparable to mineral dust in their
immersion freezing behavior when being dry generated. However, a significant
decrease in immersion freezing efficiency was observed during experiments
with wet-generated particles in LACIS and SPIN. The efficiency of
wet-generated particles is in agreement with the cold-stage measurements. In
order to understand the reason behind the deactivation, a series of chemical
composition, morphology, and crystallography analyses (single particle mass
spectrometry, scanning electron microscopy coupled with energy dispersive
X-ray microanalysis, X-ray diffraction analysis) were performed with dry- and
wet-generated particles. From these investigations, we conclude that
anhydrous CaSO4 and CaO – which, if investigated in pure form, show the
same qualitative immersion freezing behavior as observed for dry-generated
coal fly ash particles – contribute to triggering heterogeneous ice nucleation
at the particle–water interface. The observed deactivation in contact with
water is related to changes in the particle surface properties which are
potentially caused by hydration of CaSO4 and CaO. The contribution of coal
fly ash to the ambient population of ice-nucleating particles therefore
depends on whether and for how long particles are immersed in cloud droplets.
Seasonal ozone vertical profiles over North America using the AQMEII3 group of air quality models: model inter-comparison and stratospheric intrusions
Authors: Astitha Marina , Kioutsioukis Ioannis , Fisseha Ghezae Araya , Bianconi Roberto , Bieser Johannes , Christensen Jesper H. , Cooper Owen R. , Galmarini Stefano , Hogrefe Christian , Im Ulas , Johnson Bryan , Liu Peng , Nopmongcol Uarporn , Petropavlovskikh Irina , Solazzo Efisio , Tarasick David W. , Yarwood Greg
Published: October 2018

Abstract. This study evaluates simulated vertical ozone profiles produced in the
framework of the third phase of the Air Quality Model Evaluation
International Initiative (AQMEII3) against ozonesonde observations in North
America for the year 2010. Four research groups from the United States (US)
and Europe have provided modeled ozone vertical profiles to conduct this
analysis. Because some of the modeling systems differ in their meteorological
drivers, wind speed and temperature are also included in the analysis. In
addition to the seasonal ozone profile evaluation for 2010, we also analyze
chemically inert tracers designed to track the influence of lateral boundary
conditions on simulated ozone profiles within the modeling domain. Finally,
cases of stratospheric ozone intrusions during May–June 2010 are investigated
by analyzing ozonesonde measurements and the corresponding model simulations
at Intercontinental Chemical Transport Experiment Ozonesonde Network Study
(IONS) experiment sites in the western United States. The evaluation of the
seasonal ozone profiles reveals that, at a majority of the stations, ozone
mixing ratios are underestimated in the 1–6 km range. The seasonal change
noted in the errors follows the one seen in the variance of ozone mixing
ratios, with the majority of the models exhibiting less variability than the
observations. The analysis of chemically inert tracers highlights the
importance of lateral boundary conditions up to 250 hPa for the
lower-tropospheric ozone mixing ratios (0–2 km). Finally, for the stratospheric
intrusions, the models are generally able to reproduce the location and
timing of most intrusions but underestimate the magnitude of the maximum
mixing ratios in the 2–6 km range and overestimate ozone up to the first kilometer
possibly due to marine air influences that are not accurately described by
the models. The choice of meteorological driver appears to be a greater
predictor of model skill in this altitude range than the choice of air
quality model.
Characterization of biogenic primary and secondary organic aerosols in the marine atmosphere over the East China Sea
Authors: Kang Mingjie , Fu Pingqing , Kawamura Kimitaka , Yang Fan , Zhang Hongliang , Zang Zhengchen , Ren Hong , Ren Lujie , Zhao Ye , Sun Yele , Wang Zifa
Published: October 2018

Abstract. Molecular composition and abundance of sugars and secondary organic aerosols
(SOA) from biogenic sources over the East China Sea were investigated based
on gas chromatography–mass spectrometry. Biogenic SOA tracers and sugars
exhibit higher levels in the samples affected by continental air masses,
demonstrating the terrestrial outflows of organic matter to the East China
Sea. Glucose was the dominant sugar species (0.31–209, 18.8 ng m−3), followed by mannitol – a fungal spore tracer. All sugar compounds
show generally higher average concentrations in the nighttime than in the
daytime. 3-Methyl-1,2,3-butanetricarboxylic acid, one higher generation
photooxidation tracer of monoterpene SOA, was found to be the most abundant
species among measured biogenic SOA markers, suggesting the input of aged
organic aerosols through long-range transport. Fungal-spore-derived organic
carbon (OC) was the biggest contributor to total OC (0.03 %–19.8 %,
3.1 %), followed by sesquiterpene-derived secondary OC (SOC),
biomass-burning-derived OC, and monoterpene- and isoprene-derived SOC. Larger
carbon percentages of biogenic primary OCs and SOCs in total OC presented in
the terrestrially influenced aerosols indicate significant contributions of
continental aerosols through long-range transport. Positive matrix
factorization results illustrate that the secondary nitrate and biogenic SOA,
biomass burning, and fungal spores were the main sources of OC in marine
aerosols over the East China Sea, again highlighting the importance of the Asian continent as a natural emitter of biogenic organic aerosols together with
anthropogenic aerosols over the coastal marine atmosphere.
Daytime HONO, NO2 and aerosol distributions from MAX-DOAS observations in Melbourne
Authors: Ryan Robert G. , Rhodes Steve , Tully Matthew , Wilson Stephen , Jones Nicholas , Frieß Udo , Schofield Robyn
Published: October 2018

Abstract. Toxic nitrogen oxides produced by high temperature combustion are prevalent in urban environments, contributing to a significant health burden. Nitrogen oxides such as NO2 and HONO in pollution are important for hydroxyl radical (OH) production and overall oxidative capacity in urban environments; however, current mechanisms cannot explain high daytime levels of HONO observed in many urban and rural locations around the world. Here we present HONO, NO2 and aerosol extinction vertical distributions retrieved from multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements in suburban Melbourne, which are the first MAX-DOAS results from the Australian continent. Using the optimal estimation algorithm HEIPRO we show that vertical profiles for NO2 and HONO can be calculated with a low dependence on the retrieval forward model and a priori parameters, despite a lack of independent co-located aerosol or trace gas measurements. Between December 2016 and April 2017 average peak NO2 values of 8±2 ppb indicated moderate traffic pollution levels, and high daytime peak values of HONO were frequently detected, averaging 220±30 ppt in the middle of the day. HONO levels measured in Melbourne were typically lower than those recorded in the morning in other places around the world, indicating minimal overnight accumulation, but peaked in the middle of the day to be commensurate with midday concentrations in locations with much higher NO2 pollution. Regular midday peaks in the diurnal cycle of HONO surface concentrations have only previously been reported in rural locations. The HONO measured implies a daytime source term 1 ppb h−1 above the predicted photostationary state (PSS) concentration and represents an OH radical source up to 4 times stronger than from ozone photolysis alone in the lowest 500 m of the troposphere. The dependence of the high midday HONO levels on soil moisture, combined with the observed diurnal and vertical profiles, provides evidence for a strong photoactivated and ground-based daytime HONO source.
Composition of ice particle residuals in mixed-phase clouds at Jungfraujoch (Switzerland): enrichment and depletion of particle groups relative to total aerosol
Authors: Eriksen Hammer Stine , Mertes Stephan , Schneider Johannes , Ebert Martin , Kandler Konrad , Weinbruch Stephan
Published: October 2018

Abstract. Ice particle residuals (IRs) and the total aerosol particle population were
sampled in parallel during mixed-phase cloud events at the high-altitude
research station Jungfraujoch in January–February 2017. Particles were
sampled behind an ice-selective counterflow impactor (Ice-CVI) for IRs and a
heated total inlet for the total aerosol particles. A dilution set-up was
used to collect total particles with the same sampling duration as for IRs to
prevent overloading of the substrates. About 4000 particles from 10 Ice-CVI
samples (from 7 days of cloud events at temperatures at the site between
−10 and −18 ∘C) were analysed and classified with
operator-controlled scanning electron microscopy. Contamination particles
(identified by their chemical composition), most likely originating from
abrasion in the Ice-CVI and collection of secondary ice, were excluded from
further analysis. Approximately 3000 total aerosol particles (IRs and
interstitial particles) from 5 days in clouds were also analysed. Enrichment
and depletion of the different particle groups (within the IR fraction
relative to the total aerosol reservoir) are presented as an odds ratio
relative to alumosilicate (particles only
consisting of Al, Si, and O), which was chosen as reference due to the large
enrichment of this group relative to total aerosol and the relatively high
number concentration of this group in both total aerosol and the IR samples.
Complex secondary particles and soot are the major particle groups in the
total aerosol samples but are not found in the IR fraction and are hence
strongly depleted. C-rich particles (most likely organic particles) showed a
smaller enrichment compared to aluminosilicates by a factor of ∼20. The
particle groups with enrichment similar to aluminosilicate are silica, Fe
aluminosilicates, Ca-rich particles, Ca sulfates, sea-salt-containing
particles, and metal/metal oxide. Other aluminosilicates – consisting of
variable amounts of Na, K, Ca, Si, Al, O, Ti, and Fe – are somewhat more
enriched (factor ∼2) and Pb-rich particles are more (factor ∼8)
enriched than aluminosilicates. None of the sampled IR groups showed a temperature or
size dependence in respect to ice activity, which might be due to the limited
sampling temperature interval and the similar size of the particles.
Footprint plots and wind roses could explain the different total aerosol
composition in one sample (carbonaceous particle emission from the
urban/industrial area of Po Valley), but this did not affect the IR
composition. Taking into account the relative abundance of the particle
groups in total aerosol and the ice nucleation ability, we found that silica,
aluminosilicates, and other aluminosilicates were the most important ice particle
residuals at Jungfraujoch during the mixed-phase cloud events in winter 2017.
Reactive quenching of electronically excited NO2∗ and NO3∗ by H2O as potential sources of atmospheric HOx radicals
Authors: Dillon Terry J. , Crowley John N.
Published: October 2018

Abstract. Pulsed
laser excitation of NO2 (532–647 nm) or NO3
(623–662 nm) in the presence of H2O was used to initiate the
gas-phase reaction NO2∗+H2O → products
(Reaction R5) and NO3∗+H2O → products
(Reaction R12). No evidence for OH production in Reactions (R5) or
(R12) was observed
and upper limits for OH production of k5b/k5<1×10-5 and
k12b/k12<0.03 were assigned. The upper limit for k5b∕k5
renders this reaction insignificant as a source of OH in the atmosphere and
extends the studies (Crowley and Carl, 1997; Carr et al., 2009; Amedro et
al., 2011) which demonstrate that the previously reported large OH yield by
Li et al. (2008) was erroneous. The upper limit obtained for k12b∕k12 indicates that non-reactive energy transfer is the dominant mechanism
for Reaction (R12), though
generation of small but significant amounts of atmospheric
HOx and HONO cannot be ruled out. In the course of this
work, rate coefficients for overall removal of NO3∗ by
N2 (Reaction R10) and by H2O (Reaction R12) were
determined: k10=(2.1±0.1)×10-11 cm3 molecule−1 s−1 and k12=(1.6±0.3)×10-10 cm3 molecule−1 s−1. Our value of
k12 is more than a factor of 4 smaller than the single previously
reported value.
Molecular and physical characteristics of aerosol at a remote free troposphere site: implications for atmospheric aging
Authors: Schum Simeon K. , Zhang Bo , Džepina Katja , Fialho Paulo , Mazzoleni Claudio , Mazzoleni Lynn R.
Published: October 2018

Abstract. Aerosol
properties are transformed by atmospheric processes during long-range
transport and play a key role in the Earth's radiative balance. To understand
the molecular and physical characteristics of free tropospheric aerosol, we
studied samples collected at the Pico Mountain Observatory in the North
Atlantic. The observatory is located in the marine free troposphere at
2225 m above sea level, on Pico Island in the Azores archipelago. The site
is ideal for the study of long-range-transported free tropospheric aerosol
with minimal local influence. Three aerosol samples with elevated organic
carbon concentrations were selected for detailed analysis. FLEXPART
retroplumes indicated that two of the samples were influenced by North
American wildfire emissions transported in the free troposphere and one by
North American outflow mainly transported within the marine boundary layer.
Ultrahigh-resolution Fourier transform ion cyclotron resonance mass
spectrometry was used to determine the detailed molecular composition of the
samples. Thousands of molecular formulas were assigned to each of the
individual samples. On average ∼60 % of the molecular formulas
contained only carbon, hydrogen, and oxygen atoms (CHO), ∼30 %
contained nitrogen (CHNO), and ∼10 % contained sulfur (CHOS). The
molecular formula compositions of the two wildfire-influenced aerosol
samples transported mainly in the free troposphere had relatively low average
O∕C ratios (0.48±0.13 and 0.45±0.11) despite the 7–10
days of transport time according to FLEXPART. In contrast, the molecular
composition of the North American outflow transported mainly in the boundary
layer had a higher average O∕C ratio (0.57±0.17) with 3 days of
transport time. To better understand the difference between free tropospheric
transport and boundary layer transport, the meteorological conditions along
the FLEXPART simulated transport pathways were extracted from the Global
Forecast System analysis for the model grids. We used the extracted
meteorological conditions and the observed molecular chemistry to predict the
relative-humidity-dependent glass transition temperatures (Tg) of
the aerosol components. Comparisons of the Tg to the ambient
temperature indicated that a majority of the organic aerosol components
transported in the free troposphere were more viscous and therefore less
susceptible to oxidation than the organic aerosol components transported in
the boundary layer. Although the number of observations is limited, the
results suggest that biomass burning organic aerosol injected into the free
troposphere is more persistent than organic aerosol in the boundary layer
having broader implications for aerosol aging.
The global climatology of the intensity of ionospheric sporadic E layer
Authors: Yu Bingkun , Xue Xianghui , Yue Xin'an , Dou Xiankang
Published: October 2018

Abstract. On the basis of S4max data retrieved from COSMIC GPS radio occultation measurements, the long-term climatology of the intensity of Es layers is investigated for the period from December 2006 to January 2014. The global maps of Es intensity shows a high spatial resolution geographical distributions and strong seasonal dependence of Es layers. The maximum intensity of Es occurs in the midlatitudes, and its value in summer is 2–3 times larger than that in winter. A relatively strong Es layer is observed at the North and South Poles with a distinct boundary dividing the midddle latitudes and high latitudes along 60°–80° geomagnetic latitude bands. Besides, simulation results shows that the convergence of vertical ion velocity could partially explain the seasonal dependence of Es intensity. Furthermore, some disagreements between the distributions of calculated divergence of vertical ion velocity and observed Es intensity indicate that other processes such as magnetic field effects, meteoric mass influx into the earth's atmosphere and chemical processes of metallic ions should also be considered, which play an important role in the spatial and seasonal variations of Es layers.
Influence of station density and multi-constellation GNSS observations on troposphere tomography
Authors: Zhao Qingzhi , Zhang Kefei , Yao Wanqiang
Published: October 2018

Abstract. Troposphere tomography, using multi-constellation GNSS observations, has become a novel approach for the three-dimensional (3-d) reconstruction of water vapour fields. An analysis of the integration of four Global Navigation Satellite Systems (BeiDou, GPS, GLONASS and Galileo) observations is presented to investigate the impact of station density and single/multi-constellation GNSS observations on troposphere tomography. Additionally, the optimal horizontal resolution of research area is determined in Hong Kong, which considers both the number of voxels divided, and the coverage rate of discretized voxels penetrated by satellite signals. Tomography experiment reveals that the influence of station density in a GNSS network is more significant than the multi-constellation GNSS observations on the reconstruction of 3-d atmospheric water vapour profiles. Compared to the tomographic result from the multi-constellation GNSS (BeiDou, GPS, GLONASS and Galileo) observations, the RMS of SWD residuals derived from the single-GNSS observations has been decreased by 16 % when the data from the other four stations are added. Furthermore, more experiments have been carried out to analyse the contributions of different combined GNSS data to the reconstructed results, and the comparisons show some interesting results: (1) the number of iterations used in determining the weighting matrices of different equations in tomography modelling can be decreased when considering multi-constellation GNSS observations; (2) the tomographic result with multi-constellation GNSS data can improve the reconstructed quality of 3-d atmospheric water vapour by the largest RMS value of about 11 % when compared to the PPP-estimated SWD, but this was not as high as was expected.
Beam tracking strategies for fast acquisition of solar wind velocity distribution functions with high energy and angular resolutions
Authors: De Keyser Johan , Lavraud Benoit , Přech Lubomir , Neefs Eddy , Berkenbosch Sophie , Beeckman Bram , Fedorov Andrei , Marcucci Maria Federica , De Marco Rossana , Brienza Daniele
Published: October 2018

Abstract. Space plasma spectrometers have often relied on spacecraft spin to collect
three-dimensional particle velocity distributions, which simplifies the
instrument design and reduces its resource budgets but limits the velocity
distribution acquisition rate. This limitation can in part be overcome by the
use of electrostatic deflectors at the entrance of the analyser. By mounting
such a spectrometer on a Sun-pointing spacecraft, solar wind ion
distributions can be acquired at a much higher rate because the solar wind
ion population, which is a cold beam that fills only part of the sky around
its mean arrival direction, always remains in view. The present paper
demonstrates how the operation of such an instrument can be optimized through
the use of beam tracking strategies. The underlying idea is that it is much
more efficient to cover only that part of the energy spectrum and those
arrival directions where the solar wind beam is expected to be. The
advantages of beam tracking are a faster velocity distribution acquisition
for a given angular and energy resolution, or higher angular and energy
resolution for a given acquisition rate. It is demonstrated by simulation
that such beam tracking strategies can be very effective while limiting the
risk of losing the beam. They can be implemented fairly easily with
present-day on-board processing resources.
Technical note: An improved Grassberger–Procaccia algorithm for analysis of climate system complexity
Authors: Di Chongli , Wang Tiejun , Yang Xiaohua , Li Siliang
Published: October 2018

Abstract. Understanding the complexity of natural systems, such as climate
systems, is critical for various research and application purposes. A range
of techniques have been developed to quantify system complexity, among which
the Grassberger–Procaccia (G-P) algorithm has been used the most. However,
the use of this method is still not adaptive and the choice of scaling
regions relies heavily on subjective criteria. To this end, an improved G-P
algorithm was proposed, which integrated the normal-based K-means
clustering technique and random sample consensus (RANSAC) algorithm for
computing correlation dimensions. To test its effectiveness for computing
correlation dimensions, the proposed algorithm was compared with traditional
methods using the classical Lorenz and Henon chaotic systems. The results
revealed that the new method outperformed traditional algorithms in computing
correlation dimensions for both chaotic systems, demonstrating the
improvement made by the new method. Based on the new algorithm, the
complexity of precipitation, and air temperature in the Hai River
basin (HRB) in
northeastern China was further evaluated. The results showed that there
existed considerable regional differences in the complexity of both climatic
variables across the HRB. Specifically, precipitation was shown to become
progressively more complex from the mountainous area in the northwest to the
plain area in the southeast, whereas the complexity of air temperature
exhibited an opposite trend, with less complexity in the plain area. Overall,
the spatial patterns of the complexity of precipitation and air temperature
reflected the influence of the dominant climate system in the region.
Rainfall-runoff modelling using river-stage time series in the absence of reliable discharge information: a case study in the semi-arid Mara River basin
Authors: Hulsman Petra , Bogaard Thom A. , Savenije Hubert H. G.
Published: October 2018

Abstract. Hydrological models play an important role in water resources management.
These models generally rely on discharge data for calibration. Discharge time
series are normally derived from observed water levels by using a rating
curve. However, this method suffers from many uncertainties due to
insufficient observations, inadequate rating curve fitting procedures, rating
curve extrapolation, and temporal changes in the river geometry.
Unfortunately, this problem is prominent in many African river basins. In
this study, an alternative calibration method is presented using water-level
time series instead of discharge, applied to a semi-distributed rainfall-runoff model for the semi-arid and poorly gauged Mara River basin in Kenya.
The modelled discharges were converted into water levels using the
Strickler–Manning formula. This method produces an additional model output; this is a
“geometric rating curve equation” that relates the modelled discharge to
the observed water level using the Strickler–Manning formula and a calibrated
slope-roughness parameter. This procedure resulted in good and consistent
model results during calibration and validation. The hydrological model was
able to reproduce the water levels for the entire basin as well as for the
Nyangores sub-catchment in the north. The newly derived geometric rating
curves were subsequently compared to the existing rating curves. At the
catchment outlet of the Mara, these differed significantly, most likely due
to uncertainties in the recorded discharge time series. However, at the
“Nyangores” sub-catchment, the geometric and recorded discharge were almost
identical. In conclusion, the results obtained for the Mara River basin
illustrate that with the proposed calibration method, the water-level time
series can be simulated well, and that the discharge-water-level
relation can also be derived, even in catchments with uncertain or lacking rating
curve information.
Large-scale physical modelling study of a flexible barrier under the impact of granular flows
Authors: Tan Dao-Yuan , Yin Jian-Hua , Feng Wei-Qiang , Qin Jie-Qiong , Zhu Zhuo-Hui
Published: October 2018

Abstract. Flexible barriers are being increasingly applied to mitigate the danger of debris flows. However, how barriers can be better designed to withstand the impact loads of debris flows is still an open question in natural hazard engineering. Here we report an improved large-scale physical modelling device and the results of two consecutive large-scale granular flow tests using this device to study how flexible barriers react under the impact of granular flows. In the study, the impact force directly on the flexible barrier and the impact force transferred to the supporting structures are measured, calculated, and compared. Based on the comparison, the impact loading attenuated by the flexible barrier is quantified. The hydro-dynamic approaches with different dynamic coefficients and the hydro-static approach are validated using the measured impact forces.
A denoising stacked autoencoders for transient electromagnetic
signal denoising
Authors: Lin Fanqiang , Chen Kecheng , Wang Xuben , Cao Hui , Chen Danlei , Chen Fanzeng
Published: October 2018

Abstract. Transient electromagnetic method (TEM) is extremely important in geophysics. However, the secondary field signal(SFS) in TEM received by coil is easily disturbed by random noise, sensor noise and man-made noise, which results in the difficulty in detecting deep geological information. To reduce the noise interference and detect deep geological information, we apply autoencoders, an unsupervised learning model in deep learning, on the basis of analyzing the characteristic of SFS, to denoise SFS. We introduce SFSDSA, a Secondary Field Signal Denoising Stacked Autoencoders, based on deep neural networks of feature extraction and denoising. SFSDSA maps the signal points of the noise interference to the high probability points with clean signal as reference according to the deep characteristics of the signal, so as to realize the signal denoising and reduce noise interference. The method is validated by the measured data comparison, and the comparison results show that the noise reduction method can effectively reduce the noise of SFS, in contrast with the Kalman and wavelet transform methods, and strongly support the speculation of deeper underground features.
Simulation of the future sea level contribution of Greenland with a new glacial system model
Authors: Calov Reinhard , Beyer Sebastian , Greve Ralf , Beckmann Johanna , Willeit Matteo , Kleiner Thomas , Rückamp Martin , Humbert Angelika , Ganopolski Andrey
Published: October 2018

Abstract. We introduce the coupled model of the Greenland glacial system IGLOO 1.0,
including the polythermal ice sheet model SICOPOLIS (version 3.3) with hybrid
dynamics, the model of basal hydrology HYDRO and a parameterization of
submarine melt for marine-terminated outlet glaciers. The aim of this glacial
system model is to gain a better understanding of the processes important for
the future contribution of the Greenland ice sheet to sea level rise under
future climate change scenarios. The ice sheet is initialized via a
relaxation towards observed surface elevation, imposing the palaeo-surface
temperature over the last glacial cycle. As a present-day reference, we use
the 1961–1990 standard climatology derived from simulations of the regional
atmosphere model MAR with ERA reanalysis boundary conditions. For the
palaeo-part of the spin-up, we add the temperature anomaly derived from the
GRIP ice core to the years 1961–1990 average surface temperature field. For
our projections, we apply surface temperature and surface mass balance
anomalies derived from RCP 4.5 and RCP 8.5 scenarios created by MAR with
boundary conditions from simulations with three CMIP5 models. The hybrid ice
sheet model is fully coupled with the model of basal hydrology. With this
model and the MAR scenarios, we perform simulations to estimate the
contribution of the Greenland ice sheet to future sea level rise until the
end of the 21st and 23rd centuries. Further on, the impact of
elevation–surface mass balance feedback, introduced via the MAR data, on
future sea level rise is inspected. In our projections, we found the
Greenland ice sheet to contribute between 1.9 and
13.0 cm to global sea level rise until the year 2100 and between 3.5 and 76.4 cm until the year
2300, including our simulated additional sea level rise due to
elevation–surface mass balance feedback. Translated into additional sea
level rise, the strength of this feedback in the year 2100 varies from 0.4 to
1.7 cm, and in the year 2300 it ranges from 1.7 to 21.8 cm. Additionally,
taking the Helheim and Store glaciers as examples, we investigate the role of
ocean warming and surface runoff
change for the melting of outlet glaciers.
It shows that ocean temperature and subglacial discharge are about equally
important for the melting of the examined outlet glaciers.
A Race for Ice Discharge between Ice Streams on Glaciated Continental Shelves
Authors: Brouard Etienne , Lajeunesse Patrick
Published: October 2018

Abstract. Ice stream networks constitute the arteries of ice sheets through which large volumes of glacial ice are rapidly delivered from the continent to the ocean. Modifications in ice stream networks have major impact on ice sheet mass balance and global sea level. However, the mechanisms controlling ice stream switching remain poorly understood. Here, we report a flow-switch in an ice stream system that occurred during the Pliocene-Pleistocene on the northeastern Baffin Island shelf (Arctic Canada) through glacial erosion of a marginal trough. We find that up-ice propagation of ice streams through marginal troughs can lead to the piracy of neighbouring ice-catchments, which in turn induce an adjacent ice stream flow-switch and shutdown. Similar trough systems observed on many other glaciated continental shelves may be the product of such a competition for ice discharge between catchments.
Using Appreciative Inquiry to Understand the Role of Teaching Practices in Student Well-being at a Research-Intensive University
Authors: Lane Kathleen , Teng Minnie Y , Barnes Steven J , Moore Katherine , Smith Karen , Lee Michael
Published: October 2018

Appreciative inquiry (a research approach comprising four stages: Discovery, Dream, Design, and Destiny) was used at a research-intensive university to investigate which teaching practices positively influence student well-being (i.e., their health and quality of life). In a survey, undergraduate students were asked to select the teaching practices they believed best supported their well-being. Focus groups also were conducted, with: (1) students, and (2) instructors identified by students as using teaching practices that supported their well-being. Mixed-methods data-analyses subsequently were used to identify instructional strategies that support student well-being.
L’enquête appréciative (une approche de recherche qui comprend quatre étapes : découverte, rêve, conception et destinée) a été utilisée dans une université centrée sur la recherche pour enquêter sur les pratiques d’enseignement et déterminer lesquelles influencent positivement le bien-être des étudiants (c’est-à-dire leur santé et leur qualité de vie). Dans un sondage, on a demandé aux étudiants de premier cycle de choisir les pratiques d’enseignement qui, selon eux, favorisaient le mieux leur bien-être. Des groupes de discussion ont également été organisés, avec (1) des étudiants et (2) des instructeurs identifiés par les étudiants comme étant ceux qui employaient des pratiques d’enseignement qui favorisaient leur bien-être. Ensuite, les données ont été analysées selon des méthodes mixtes pour identifier les stratégies d’instruction qui favorisent le bien-être des étudiants.
A Common Book: A Novel Approach to Teaching and Learning
Authors: Ferguson Kristen A , Brown Natalya , Piper Linda
Published: October 2018

Most research on common book programs focuses on student outcomes. This paper presents a study about the impact of a common book program on teaching and learning practices at a small mainly undergraduate university. This study consists of two phases. In Phase 1, we surveyed faculty members (N= 32, a response rate of 21.3%), about the influence of the program on teaching practices and dialogue with colleagues as well as their perceptions of the program’s impact on student learning. In Phase 2, we conducted interviews with business faculty, who were early program adopters (N=8). Most respondents believed that students benefited from the program. Faculty members perceived the common book program as a tool that facilitated course content and enhanced students’ literacy. While responses were mixed about the perceived impact on teaching practices, faculty members interviewed felt that the common book program created opportunities for discussion about teaching and learning.
La majorité des recherches menées sur les programmes de livre commun se concentrent sur les résultats des étudiants. Cet article présente une étude qui a porté sur l’impact d’un programme de livre commun sur les pratiques pédagogiques dans une petite université offrant principalement des études de premier cycle. Cette étude s’est déroulée en deux phases. Au cours de la Phase I, nous avons mené une enquête auprès de professeurs (N = 32, avec un taux de réponse de 21,3 %) concernant l’influence du programme sur les pratiques d’enseignement et le dialogue avec les collègues, ainsi que concernant leurs perceptions de l’impact du programme sur l’apprentissage des étudiants. Au cours de la Phase II, nous avons mené des entrevues avec des professeurs d’administration des affaires qui avaient adopté le programme dès sa phase initiale (N = 8). La plupart des répondants ont déclaré que selon eux, les étudiants avaient bénéficié du programme. Les professeurs ont considéré le programme de livre commun comme un outil qui simplifie le contenu du cours et améliore l’alphabétisation des étudiants. Bien que les réponses aient été variées en ce qui concerne la perception de l’impact sur les pratiques d’enseignement, les professeurs interrogés ont indiqué que selon eux, le programme de livre commun avait créé des occasions de discussion sur l’enseignement et l’apprentissage.
Measuring the Impact of a Weeklong Fall Break on Stress Physiology in First Year Engineering Students
Authors: Khan Ayesha , Poole Heather , Beaton Elliott A
Published: October 2018

Canadian post-secondary institutions are increasingly introducing a fall break into their term calendars, with the stated goal of reducing student stress and improving academic success. We conducted a pilot study around the time of this fall break during which we collected saliva samples to measure the ratio of two metabolic hormones (cortisol and dehydroepiandrosterone (DHEA)) from first-year male engineering students in order to document possible changes in their stress levels before and after the break. Participants self-identified a particular day in the week prior to the break that they considered to be most stressful, followed by a day in the week after the break that was perceived to be equally stress-inducing. A control sample of student engineers was recruited from another university with equivalent academic rigour but without a fall break. Students who experienced the fall break exhibited a marginally lower ratio of cortisol to DHEA after the break than did those who did not experience the break indicating a difference in psychological stress. Since fall breaks are now increasing in popularity, we make the recommendation that it is imperative to empirically investigate their impact on student mental health.
Un nombre de plus en plus grand d’établissements post-secondaires introduisent un congé d’automne dans leur calendrier, avec l’objectif déclaré de réduire le stress des étudiants et d’améliorer la réussite académique. Nous avons mené une étude pilote aux alentours de ce congé d’automne au cours duquel nous avons recueilli des échantillons de salive auprès d’étudiants mâles de première année en génie afin de mesurer le ratio de deux hormones métaboliques (le cortisol et la déhydroépiandrostérone - la DHEA)) et pour documenter les changements possibles dans leurs niveaux de stress avant et après le congé. Les participants ont identifié eux-mêmes un jour spécifique de la semaine avant le congé qu’ils considéraient comme étant le plus stressant, suivi par un jour particulier de la semaine après le congé qu’ils percevaient comme étant aussi stressant. Un échantillon témoin d’étudiants en génie a été recruté dans une autre université où la rigueur académique était équivalente mais où il n’y avait pas de congé d’automne. Les étudiants qui ont bénéficié d’un congé d’automne ont manifesté un ratio plus bas de cortisol par rapport à la DHEA après le congé par rapport aux étudiants qui n’avaient pas bénéficié d’un tel congé, ce qui indique une différence de stress psychologique. Étant donné que la popularité des congés d’automne est en augmentation, nous recommandons qu’il est impératif d’établir empiriquement leur impact sur la santé mentale des étudiants.
Ascotricha microspora sp. nov. from Cayman Islands
Authors: Li De-Wei , Zhao Guihua
Published: October 2018

A new hyphomycete species, Ascotricha microspora collected from Cayman Islands in the Caribbean, is described and illustrated. The asexual fungus differs from Dicyma vesiculifera by having smaller, colorless conidia. Ascotricha rugispora (≡ Surculiseries
rugispora) and A. funiculosa (≡ Dicyma funiculosa) are proposed as new combinations.
Neopestalotiopsis rosicola sp. nov. causing stem canker of Rosa chinensis in China
Authors: Jiang Ning , Bonthond Guido , Fan Xin-Lei , Tian Cheng-Ming
Published: October 2018

Two specimens of Neopestalotiopsis were collected from China rose in Jiangsu Province, China. Cankers and conidiomata were formed on stems of the infected hosts. Phylogenetic analysis of the combined ITS, tef1, and tub2 DNA markers revealed that both strains were conspecific
and different from all other described Neopestalotiopsis species. The two strains are described and illustrated here as a new species, Neopestalotiopsis rosicola, and compared with related species genetically, morphologically and in host association. This is the first report
of Neopestalotiopsis species causing China rose stem canker in China.
Distribution of Alternaria species among sections. 5. Species producing conidia with many longitudinal septa
Authors: Gannibal Philipp B. , Lawrence Daniel P.
Published: October 2018

Morphological examination of material conforming to the morphological descriptions of Alternaria species producing conidia with many longitudinal septa (but not phylogenetically characterized) allowed the inclusion of additional species in Alternaria sect. Alternaria
(4 spp.; total spp. = 66), A. sect. Cheiranthus (1 sp.; total spp. = 3), A. sect. Gypsophilae (1 sp.; total spp. = 9), A. sect. Infectoriae (2 spp.; total spp. = 36), and A. sect. Panax (2 spp.; total spp. = 7). A complete list
of species included in Alternaria sections Cheiranthus, Gypsophilae, and Panax is presented. Sixteen species were found to have intermediate morphology and could not be unambiguously assigned to any section.
Craspedodidymum guatemalense sp. nov. from Guatemala
Authors: Figueroa Ricardo , Bran Maria Del Carmen , Morales Osberth , Morataya Edelwaiz , Minter David W. , Castañeda-Ruiz Rafael F.
Published: October 2018

Craspedodidymum guatemalense, a new species collected from decaying bark of Quercus, is described and illustrated. The fungus is characterized by its allantoid to fabiform, unicellular, smooth, brown conidia. Illustrations and a key to accepted species of Craspedodidymum
are provided.
Peltigera neodegenii sp. nov. from Central China
Authors: Han Liu-Fu , Xu Xiao-Min , Yang Jing-Yuan , Guo Shou-Yu
Published: October 2018

Peltigera neodegenii from Central China is described and illustrated as a new species. It is similar in general appearance to P. degenii, P. membranacea, and P. canina, but is distinguished by its shiny upper surface in the central part of lobes, tomenta around
the margins of upper surface of lobes, distinct and raised veins on the lower surface of lobes, and simple rhizines. Comparisons of the ITS (ITS1, 5.8S, ITS2) sequences of the nuclear ribosomal DNA repeat tandem, both in phylogenetic analysis and secondary structure models of ITS2, support
the taxonomic distinctness of this species.
Arcyriatella congregata from Mexico: a second world record
Authors: Lizárraga Marcos , Moreno Gabriel
Published: October 2018

The rare myxomycete Arcyriatella congregata, previously known only from Brazil, is redescribed from Mexican material. LM and SEM photographs of the most important micro- and macroscopic characters are provided.
Rhexoampullifera marquesii sp. nov. on submerged twigs from a stream in Brazil
Authors: Conceição Lucas Barbosa , Gusmão Luís Fernando Pascholati
Published: October 2018

The new species Rhexoampullifera marquesii, collected in Bahia state, northeast Brazil on submerged decaying twigs, is described and illustrated. The fungus is mainly characterized by cylindrical, 6–15-septate, brown to dark brown conidia. A key and a synopsis table to
Rhexoampullifera species are provided.
“Yes, the Whole Approach Is Questionable, Yes, False”: Phenomenology and the New Realism
Authors: Coate Matthew
Published: October 2018

The recent turn to realism in Continental philosophy leaves phenomenology in a precarious position, for it appears that we commit ourselves to a sort of idealism whenever we employ the phenomenological method. I will argue in this article, however, that this appearance is deceptive and that, instead, phenomenology provides support not just for realism but for a position I will call the “new realism,” which not only affirms the reality of conditioned, spatiotemporal beings but denies the existence of any type of eternal or unchanging being in which they would ostensibly find their unconditioned condition or source.
Genetic diversity and population structure in caprifigs (Ficus carica var. caprificus) using SSR markers
Authors: Caliskan Oguzhan , Bayazit Safder , Ilgin Muruvvet , Karatas Nesrin , Ergul Ali
Published: October 2018

Abundant wild and cultivated fig germplasm can be found in Turkey, a center of diversity for figs; however, many of these valuable genetic resources have not yet been identified or characterized using molecular markers. In the present study, microsatellite markers were used to characterize a set of 96 caprifig (Ficus carica var. caprificus) accessions from Turkey. The caprifig accessions showed considerable polymorphism with an average of 8.3 alleles per locus. The number of alleles per locus varied from three for the loci LMFC18 and LMFC23, to 14 for the loci FCUPO38-6 and FCUPO08. Genetic distance values and cluster analyses revealed high genetic similarities, except for the reference group, among the caprifig groups. Factorial correspondence analysis also separated the caprifig groups, suggesting that caprifig populations from Turkey were unmixed, probably because of low gene flow, likely because germplasm has not yet been moved among geographical areas and because many caprifig populations arose from propagation by seed. In our population structure analysis, the caprifig accessions could be grouped according to the regions from where they were sampled. Our molecular data revealed great genetic diversity within this caprifig germplasm. This genetically rich caprifig germplasm resource will be useful for both fig breeding programs and analysis of the complex genetic structure of figs that reproduce using various pollination strategies.
Pig’s behavioral response in nursery and growth phases to environmental enrichment objects
Authors: Foppa Luciana , Caldara Fabiana R. , De Moura Rafael , Machado Simone P. , Nääs Irenilza A. , Garcia Rodrigo G. , Gonçalves Liliane M. P. , De Oliveira Geyssane F.
Published: October 2018

The objective of this research was to evaluate the effect of environmental enrichment on the behavior of pigs in nursery and growth phases. (i) Ninety animals (females, 65 days, 25 kg) were divided into three treatments (T1- Pen enriched with objects made of destructible material by the animal, T2- Pen enriched with objects made of non-destructible material by the animal, T3- Pen without environmental enrichment objects - control treatment) - in a completely randomized design and reference of the animals by objects of enrichment of different colors (red, blue or yellow). (ii) males, 25 days old, 7 kg were distributed in a completely randomized design with four treatments (cloves, garlic, alternating aromas and absence of control smells) and six replicates each. (iii) determine the appropriate ratio between the number of enrichment objects and the animals present in the animals (n = 138; females; 65 days; 25 kg) were distributed in three treatments, in a completely randomized experimental design (proportion of one enrichment object for each 1511 animals or 9 animals, respectively). Environmental enrichment objects made from destructible materials are more attractive to pigs. No preference for pigs for environmental enrichment objects of specific colors was observed. Environmental enrichment objects with garlic aroma had a repellent effect. No effect was observed of alternating perfumes in the animals retaining interest in the objects since the smell of garlic acted as a repellent. Thus, the proportion of one enrichment object for each 15 pigs is sufficient to avoid problems of dispute between the animals.