bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of snow cover and soil freeze/thaw cycles affecting boreal-arctic soil carbon dynamics
Authors: Yi Y. , Kimball J. S. , Rawlins M. A. , Moghaddam M. , Euskirchen E. S.
Published: July 2015

Abstract. Northern Hemisphere permafrost affected land areas contain about twice as much carbon as the global atmosphere. This vast carbon pool is vulnerable to accelerated losses through mobilization and decomposition under projected global warming. Satellite data records spanning the past 3 decades indicate widespread reductions (∼ 0.8–1.3 days decade−1) in the mean annual snow cover extent and frozen season duration across the pan-Arctic domain, coincident with regional climate warming trends. How the soil carbon pool responds to these changes will have a large impact on regional and global climate. Here, we developed a coupled terrestrial carbon and hydrology model framework with detailed 1-D soil heat transfer representation to investigate the sensitivity of soil organic carbon stocks and soil decomposition to changes in snow cover and soil freeze/thaw processes in the Pan-Arctic region over the past three decades (1982–2010). Our results indicate widespread soil active layer deepening across the pan-Arctic, with a mean decadal trend of 6.6 ± 12.0 (SD) cm, corresponding with widespread warming and lengthening non-frozen season. Warming promotes vegetation growth and soil heterotrophic respiration, particularly within surface soil layers (≤ 0.2 m). The model simulations also show that seasonal snow cover has a large impact on soil temperatures, whereby increases in snow cover promote deeper (≥ 0.5 m) soil layer warming and soil respiration, while inhibiting soil decomposition from surface (≤ 0.2 m) soil layers, especially in colder climate zones (mean annual T ≤ −10 °C). Our results demonstrate the important control of snow cover in affecting northern soil freeze/thaw and soil carbon decomposition processes, and the necessity of considering both warming, and changing precipitation and snow cover regimes in characterizing permafrost soil carbon dynamics.
Revisiting carbonate chemistry controls on planktic foraminifera Mg / Ca: implications for sea surface temperature and hydrology shifts over the Paleocene–Eocene Thermal Maximum and Eocene–Oligocene Transition
Authors: Evans D. , Wade B. S. , Henehan M. , Erez J. , Müller W.
Published: July 2015

Abstract. Much of our knowledge of past ocean temperatures comes from the foraminifera Mg / Ca palaeothermometer. Several non-thermal controls on foraminifera Mg incorporation have been identified, of which vital-effects, salinity and secular variation in seawater Mg / Ca are the most commonly considered. Ocean carbonate chemistry is also known to influence Mg / Ca, yet this is rarely considered as a source of uncertainty either because (1) precise pH and [CO32−] reconstructions are sparse, or (2) it is not clear from existing culture studies how a correction should be applied. We present new culture data of the relationship between carbonate chemistry for the surface-dwelling planktic species Globigerinoides ruber, and compare our results to data compiled from existing studies. We find a coherent relationship between Mg / Ca and the carbonate system and argue that pH rather than [CO32−] is likely to be the dominant control. Applying these new calibrations to datasets for the Paleocene–Eocene Thermal Maximum (PETM) and Eocene–Oligocene Transition (EOT) enable us to produce a more accurate picture of surface hydrology change for the former, and a reassessment of the amount of subtropical precursor cooling for the latter. We show that properly corrected Mg / Ca and δ18O datasets for the PETM imply no salinity change, and that the amount of precursor cooling over the EOT has been previously underestimated by ∼ 2 °C based on Mg / Ca. Finally, we present new laser-ablation data of EOT-age Turborotalia ampliapertura from St Stephens Quarry (Alabama), for which a solution ICPMS Mg / Ca record is available (Wade et al., 2012). We show that the two datasets are in excellent agreement, demonstrating that fossil solution and laser-ablation data may be directly comparable. Together with an advancing understanding of the effect of Mg / Casw, the coherent picture of the relationship between Mg / Ca and pH that we outline here represents a step towards producing accurate and quantitative palaeotemperatures using this proxy.
A framework for the cross-sectoral integration of multi-model impact projections: land use decisions under climate impacts uncertainties
Authors: Frieler K. , Levermann A. , Elliott J. , Heinke J. , Arneth A. , Bierkens M. F. P. , Ciais P. , Clark D. B. , Deryng D. , Döll P. , Falloon P. , Fekete B. , Folberth C. , Friend A. D. , Gellhorn C. , Gosling S. N. , Haddeland I. , Khabarov N. , Lomas M. , Masaki Y. , Nishina K. , Neumann K. , Oki T. , Pavlick R. , Ruane A. C. , Schmid E. , Schmitz C. , Stacke T. , Stehfest E. , Tang Q. , Wisser D. , Huber V. , Piontek F. , Warszawski L. , Schewe J. , Lotze-Campen H. , Schellnhuber H. J.
Published: July 2015

Abstract. Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impact-model setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making. Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop- and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making.
Inconsistency in precipitation measurements across Alaska and Yukon border
Authors: Scaff L. , Yang D. , Li Y. , Mekis E.
Published: July 2015

Abstract. This study quantifies the inconsistency in gauge precipitation observations across the border of Alaska and Yukon. It analyses the precipitation measurements by the national standard gauges (NWS 8-in gauge and Nipher gauge), and the bias-corrected data to account for wind effect on the gauge catch, wetting loss and trace events. The bias corrections show a significant amount of errors in the gauge records due to the windy and cold environment in the northern areas of Alaska and Yukon. Monthly corrections increase solid precipitation by 135 % in January, 20 % for July at the Barter Island in Alaska, and about 31 % for January and 4 % for July at the Yukon stations. Regression analyses of the monthly precipitation data show a stronger correlation for the warm months (mainly rainfall) than for cold month (mainly snowfall) between the station pairs, and small changes in the precipitation relationship due to the bias corrections. Double mass curves also indicate changes in the cumulative precipitation over the study periods. This change leads to a smaller and inverted precipitation gradient across the border, representing a significant modification in the precipitation pattern over the northern region. Overall, this study discovers significant inconsistency in the precipitation measurements across the US and Canada border. This discontinuity is greater for snowfall than for rainfall, as gauge snowfall observations have large errors in the windy and cold conditions. This result will certainly impact regional, particularly cross borders, climate and hydrology investigations.
Dialogic action in climate change discussions: An international study of high school students in China, New Zealand, Norway and the United States
Authors: Arya Diana J. , Parker Jessica K.
Published: July 2015

Global efforts to prepare young developing minds for solving current and future challenges of climate change have advocated interdisciplinary, issues-based instructional approaches in order to transform traditional models of science education as delivering conceptual facts (UNESCO, 2014). This study is an exploration of the online interactions in an international social network of high school students residing in Norway, China, New Zealand and the United States (N=141). Students participated in classroom-based and asynchronous online discussions about adapted versions of seminal scientific studies with facilitative support from seven scientists across various fields. Grounded in a language-in-use frame for investigating facilitation and demonstrations of problem-based and evidence-based reasoning (Kelly & Chen, 1999), we traced the varied questions, assertions, and evidentiary sources within student-led online discussions. We found that questions from scientific experts in the form of unconstrained, open-ended invitations for exploration were followed by students’ acknowledgement and consideration of complex and, at times, conflicting sociopolitical and economic positions about climate change issues. These findings suggest that broadening science classroom discussions to include socially relevant, unsolved issues like climate change could open potential entry points for a dialogic approach that fosters a scientific community in the classroom.
Information Management in Cancer Registries: Evaluating the Needs for Cancer Data Collection and Cancer Research
Authors: Zachary Iris , Boren Suzanne A , Simoes Eduardo , Jackson-Thompson Jeannette , Davis J. Wade , Hicks Lanis
Published: July 2015

Cancer registry data collection involves, at a minimum, collecting data on demographics, tumor characteristics, and treatment. A common, identified, and standardized set of data elements is needed to share data quickly and efficiently with consumers of this data. This project highlights the fact that, there is a need to develop common data elements; Surveys were developed for central cancer registries (CCRs) and cancer researchers (CRs) at NCI-designated Cancer Centers, in order to understand data needs. Survey questions were developed based on the project focus, an evaluation of the research registries and database responses, and systematic review of the literature. Questions covered the following topics: 1) Research, 2) Data collection, 3) Database/ repository, 4) Use of data, 5) Additional data items, 6) Data requests, 7) New data fields, and 8) Cancer registry data set. A review of the surveys indicates that all cancer registries’ data are used for public health surveillance, and 96% of the registries indicate the data are also used for research. Data are available online in interactive tables from over 50% of CRs and 87% of CCRs. Some other survey responses indicate that CCR treatment data are not complete for example treatment data, however cancer researchers are interested in treatment variables from CCRs. Cancer registries have many data available for review, but need to examine what data are needed and used by different entities. Cancer Registries can further enhance usage through collaborations and partnerships to connect common interests in the data by making registries visible and accessible.Keywords: Public Health; Disease Registries; Disease Reporting
Public Health and Epidemiological Databases for the Enhancement of Medical Education
Authors: Sajid Jamal Qazi Mohd. , Siddiqui Mughees Uddin , Alzohairy Mohammad Abdulrahman , Al Karawi Mohammed Abdullah
Published: July 2015

The collaboration of public health education and information technology has made patient care safer and more reliable than before. Nurses and doctors use handheld computers to record a patient's medical history and check that they are administering the correct treatment. Fortunately Public Health Informatics (PHI) is the intersecting point of technology and public health. Therefore, the inclusion of online medical and epidemiology  databases in the course curriculum of  budding medical professionals and postgraduate students would be beneficial in enhancing the quality of health care,  extensive epidemiological research, health education, health policies, health planning and consumer satisfaction as well. The purpose of this article is to discuss and provide introduction of various databases which have huge information and it could be used to enhance the public health education.Keywords: Information Technology, Public Health Informatics, Public Health Education, Databases.
Review of literature on Graduate Employability
Authors: Sumanasiri Erabaddage Gishan Tharanga , Yajid Mohd Shukri Ab , Khatibi Ali
Published: July 2015

There is increasing pressure from governments, funding organizations, students and parents on universities around the world since graduate employability has been clearly recognized as one of the main objectives of university education. Accreditation bodies also appear to measure quality of education through the contributions made towards employability. In such a context one would assume that employability of university graduates to be clearly understood and extensively researched area. However, the real situation appears to be one which requires the urgent attention of all stakeholders of university education. A review of literature on graduate employability is a clear need today and current paper achieves this by summarizing the major articles on university graduate employability theoretical frameworks and empirical studies. Despite the large number of studies, graduate employability appears to be suffering from the problems of lack of theoretical control and politicization which appear to have become major obstacles for future developments of the concept. 
On the Road from Dante to Jack Kerouac (Stopping by Frost, Pound, and Eliot)
Authors: Barnstone Willis
Published: July 2015

Dante is our unique epic poet whose medium is song, the canto. He is also a cruel theologian punishing not only lovers for misbehavior, but the great pre-Christian figures like his guide Virgil for not having been baptized. On love he journeys through hellish love on low earth and ultimately into the highest Empyrean where, guided by evermore beautiful and remote Beatrice, he is enveloped in light and can see God. Jack Kerouac takes his title On the Road from the first line of Canto 1. His ecstatic love takes place not with angels of the Primum Mobile but with wild drunken outsiders like himself. He seeks in his way a fun Inferno to find Zen satori. These two wondrous cranks, drunk on language, seize us with their wayward adventure on earth and in their celestial escapades.
The Much-Maligned Panegyric:
Authors: Gould Rebecca
Published: July 2015

This article examines the panegyric across the literary traditions of West, South, and East Asia, concentrating on Arabo-Persian qaṣīda, the Sanskrit praśasti, and the Chinese fu. In radically different albeit analogous ways, these three genres elaborated a political aesthetics of literary form that corresponded to many key features of epideictic rhetoric. All three genres cultivated a metapoetics for praising rulers and patrons that bolstered poetry's political status. All three genres were additionally conditioned by the panegyric's characteristic indirection whereby the object of praise shifts in the course of the text's unfolding. In elucidating a differential politics of literary form, the essay aims to deepen the interface between poetics and power in premodern literary cultures and to stimulate the discipline of comparative literature to move beyond its reliance on more familiar European genres as normative modes of literary expression.
Justice et culture militaires dans le Pays des Illinois au XVIIIe siècle à travers une affaire de désertion (1752)
Authors: Wenzel Éric
Published: July 2015

À l’époque de la Nouvelle-France, le Pays des Illinois, ou Haute Louisiane, fait la jonction entre le Canada et la Basse Louisiane. Depuis quelques années, les historiens s’intéressent à ce territoire et en démontrent l’importance économique, stratégique et l’originalité de sa société. La justice qui s’y pratique, sous le contrôle de l’institution militaire, reste en revanche encore peu connue. Une affaire de désertion au milieu du XVIIIe siècle permet de mieux saisir les enjeux et les difficultés de la justice militaire dans la haute vallée du Mississippi sous le Régime français.
Les Canadiens passés en France à la Conquête
Authors: Larin Robert
Published: July 2015

Cet article aborde l’histoire du mouvement migratoire provoqué par la Conquête en attirant l’attention sur un groupe de 127 Canadiens « nécessiteux » présents à La Rochelle en 1761-1762. Qui étaient-ils et pourquoi avaient-ils quitté le Canada ? Comment ont-ils été traités et qu’allaient-ils devenir en France ? Certains allaient-ils revenir au Canada ? L’expérience individuelle et collective de ces Canadiens de la classe populaire compose une image spécifique et particulièrement expressive faisant contrepoids à la représentation historiographique traditionnelle des nobles, officiers militaires et autres Canadiens de l’élite sociale passés en France à la Conquête.
De la protection du propriétaire à la gestion du risque commercial : l’évolution du contrat à forfait en droit québécois
Authors: Paquin Julie
Published: July 2015

Malgré la volonté affirmée du législateur de reprendre dans le Code civil du Québec le droit antérieur relatif au contrat à forfait, la formulation de l’article 2109 CcQ diffère sur plusieurs points de celle de son prédécesseur, l’article 1690 CcBC. On peut donc se demander dans quelle mesure l’adoption du Code civil du Québec a entraîné ou signalé une modification du droit québécois en matière de contrats à forfait. Dans le présent article, nous comparerons les diverses interprétations des articles 1690 CcBC et 2109 CcQ et mettrons en lumière certaines incertitudes qui persistent relativement aux effets de ce dernier. Enfin, nous tenterons de mieux comprendre ces incertitudes à la lumière de la manière dont le concept de contrat d’entreprise a évolué au cours du 20e siècle.
Stigmatizing beliefs: How leading patient medication education groups on an inpatient psychiatric unit impacts pharmacy learners
Authors: Hillman Ashley , Kennedy Lindsey , Garris Shauna , McLaughlin Jacqueline E. , Rhoney Denise H.
Published: July 2015

Introduction

Stigma is an important challenge facing patients with mental illness. Stigmatizing attitudes may impact the quantity and quality of care patients receive. Interaction with these patients may reduce stigmatizing attitudes in pharmacy learners. Patient medication education groups (PMEGs) provide learners with an opportunity for this interaction. The objectives of the study were to evaluate pharmacy learner's attitudes toward patients with mental illness and their comfort and ability to provide pharmaceutical services to this population before and after leading a PMEG on an adolescent inpatient psychiatric unit and to evaluate the feasibility of a larger, future trial.

Methods

Third- or fourth-year student pharmacists or first-year pharmacy residents observed a postgraduate year-2 (PGY2) pharmacy specialty resident in psychiatry leading PMEGs on the adolescent unit of an inpatient psychiatric hospital. Then, they discussed their own ideas for design and delivery of a group (with feedback from the PGY2 resident) and, under observation of the PGY2, led their own group. The study used a mixed-methods approach consisting of a presurvey and postsurvey learning experience survey as well as reflective statements. The presurvey consisted of 2 previously validated measures that evaluate stigma toward people with mental illness—the Social Distance Scale (SDS) and the Opening Minds Scale for Health Care Providers (OMS-HC). The postsurvey also consisted of the SDS and OMS-HC and included program evaluation questions that examined the learners' impression of patients with mental illness, their ability and comfort with providing pharmaceutical services to patients with mental illness, and their reflections on the experience.

Results

Seven pharmacy learners participated, and 5 completed both the prelearning and postlearning experience survey for a 71% response rate. There was a median decrease in stigmatizing beliefs of 1 point on the SDS, and a median 5-point drop in the OMS-HC scale. The postintervention questions yielded results primarily of strongly agree or agree with the statements evaluating the other objectives, and the reflection statements brought up the additional value of the educational intervention. Finally, the feasibility and value of a larger trial were confirmed.

Discussion

The value of pharmacy learners teaching PMEGs on stigmatizing beliefs toward patients with mental illness was confirmed. The effectiveness of a model of observing, designing, and delivering a PMEG was also postulated and will be further examined with a larger trial. Future research will also focus on examining the impact of this model on patient outcomes.
Hypoglycemia from a look-alike, sound-alike medication error
Authors: Milton Robin M. , Washington Nicole B. , Brahm Nancy
Published: July 2015

Objective

To describe the effects of a look-alike, sound-alike medication error on the glycemic control and psychiatric well-being of a 23-year-old man.

Case Summary

A 23-year-old man presented to the university-based Integrated Multidisciplinary Program of Assertive Community Treatment (IMPACT) team with a diagnosis of schizoaffective disorder, most recent episode manic, and hypertension. The patient was prescribed chlorpromazine 100 mg daily to treat symptoms of psychosis and anxiety. The anxiety, however, persisted and escalated over the following 2 weeks. Upon physical examination of the patient's medications, it was discovered that the patient was inadvertently given chlorpropamide in place of the chlorpromazine. Evaluations, clinical presentation, the medication list, and criteria for an adverse drug event indicated a probable relationship (7 of 12) between the use of chlorpropamide and a hypoglycemic episode. The medication error was noted and corrective actions were taken. Within 1 week of the corrective actions, the patient's anxiety improved.

Discussion

When working with psychiatric patients, it is important to physically review all medications when expected responses are not achieved or when new psychiatric or physiological symptoms present. Approximately one-fourth of medication errors in the United States are drug name confusion errors. These errors must be universally addressed by all parties involved in the medication process. Effective safeguards are available and must be implemented by manufacturers, physicians, pharmacists, nurses, and all health care professionals to prevent look-alike, sound-alike medication errors.
Evaporation variability under climate warming in five reanalyses and its association with pan evaporation over China
Authors: Su Tao , Feng Taichen , Feng Guolin
Published: July 2015

With the motivation to identify actual evapotranspiration (AE) variability under climate warming over China, an assessment is made from five sets of reanalysis data sets [National Centers for Environmental Prediction‐National Center for Atmospheric Research (NCEP‐NCAR), NCEP‐Department of Energy (NCEP‐DOE), Modern‐Era Retrospective Analysis for Research and Applications (MERRA), Interim Reanalysis, and Japanese 55‐year Reanalysis (JRA‐55)]. Based on comparison with AE estimates calculated using the Budyko equation, all five reanalysis data sets reasonably reproduce the spatial patterns of AE over China, with a clearly southeast‐northwest gradient. Overall, JRA‐55 (NCEP‐DOE) gives the lowest (highest) reanalysis evaporation (RE) values. From 1979 to 2013, dominant modes of RE among five reanalyses are extracted using multivariate empirical orthogonal function analysis. Accordingly, the interdecadal variation of RE is likely driven by the change of temperature, and the interannual variation is constrained by the water supply conditions. Under climate warming, RE increase in the Northwest China, Yangtze‐Huaihe river basin, and South China, while they decrease in Qinghai‐Tibet Plateau, and northern and Northeast China. Moreover, the relationship between RE and pan evaporation (PE) are comprehensively evaluated in space‐time. Negative correlations are generally confirmed in nonhumid environments, while positive correlations exist in the humid regions. Our analysis supports the interpretation that the relationship between PE and AE was complementary with water control and proportional with energy control. In view of data availability, important differences in spatial variability and the amount of RE can be found in Northwest China, the Qinghai‐Tibet Plateau, and the Yangtze River Basin. Generally speaking, NCEP‐NCAR and MERRA have substantial problems on describing the long‐term change of RE; however, there are some inaccuracies in the JRA‐55 estimates when focusing on the year‐to‐year variation.
Ocean nutrient pathways associated with the passage of a storm
Authors: Rumyantseva Anna , Lucas Natasha , Rippeth Tom , Martin Adrian , Painter Stuart C. , Boyd Timothy J. , Henson Stephanie
Published: July 2015

Storms that affect ocean surface layer dynamics and primary production are a frequent occurrence in the open North Atlantic Ocean. In this study we use an interdisciplinary data set collected in the region to quantify nutrient supply by two pathways associated with a storm event: entrainment of nutrients during a period of high wind forcing and subsequent shear spiking at the pycnocline due to interactions of storm‐generated inertial currents with wind. The poststorm increase in surface layer nitrate (by ~20 mmol m−2) was predominantly driven by the first pathway: nutrient intrusion during the storm. Alignment of poststorm inertial currents and surface wind stress caused shear instabilities at the ocean pycnocline, forming the second pathway for nutrient transport into the euphotic zone. During the alignment period, pulses of high‐turbulence nitrate flux through the pycnocline (up to 1 mmol m−2 d−1; approximately 25 times higher than the background flux) were detected. However, the impact of the poststorm supply was an order of magnitude lower than during the storm due to the short duration of the pulses. Cumulatively, the storm passage was equivalent to 2.5–5% of the nitrate supplied by winter convection and had a significant effect compared to previously reported (sub)mesoscale dynamics in the region. As storms occur frequently, they can form an important component in local nutrient budgets.
Sea‐air CO2 exchange in the western Arctic coastal ocean
Authors: Evans Wiley , Mathis Jeremy T. , Cross Jessica N. , Bates Nicholas R. , Frey Karen E. , Else Brent G. T. , Papkyriakou Tim N. , DeGrandpre Mike D. , Islam Fakhrul , Cai Wei‐Jun , Chen Baoshan , Yamamoto‐Kawai Michiyo , Carmack Eddy , Williams William. J. , Takahashi Taro
Published: July 2015

The biogeochemical seascape of the western Arctic coastal ocean is in rapid transition. Changes in sea ice cover will be accompanied by alterations in sea‐air carbon dioxide (CO2) exchange, of which the latter has been difficult to constrain owing to sparse temporal and spatial data sets. Previous assessments of sea‐air CO2 flux have targeted specific subregional areas of the western Arctic coastal ocean. Here a holistic approach is taken to determine the net sea‐air CO2 flux over this broad region. We compiled and analyzed an extensive data set of nearly 600,000 surface seawater CO2 partial pressure (pCO2) measurements spanning 2003 through 2014. Using space‐time colocated, reconstructed atmospheric pCO2 values coupled with the seawater pCO2 data set, monthly climatologies of sea‐air pCO2 differences (ΔpCO2) were created on a 0.2° latitude × 0.5° longitude grid. Sea‐air CO2 fluxes were computed using the ΔpCO2 grid and gas transfer rates calculated from climatology of wind speed second moments. Fluxes were calculated with and without the presence of sea ice, treating sea ice as an imperfect barrier to gas exchange. This allowed for carbon uptake by the western Arctic coastal ocean to be assessed under existing and reduced sea ice cover conditions, in which carbon uptake increased 30% over the current 10.9 ± 5.7 Tg C (1 Tg = 1012 g) yr−1 of sea ice‐adjusted exchange in the region. This assessment extends beyond previous subregional estimates in the region in an all‐inclusive manner and points to key unresolved aspects that must be targeted by future research.
Varying styles of magmatic strain accommodation across the East African Rift
Authors: Muirhead James D. , Kattenhorn Simon A. , Le Corvec Nicolas
Published: July 2015

Observations of active dike intrusions provide present day snapshots of the magmatic contribution to continental rifting. However, unravelling the contributions of upper crustal dikes over the timescale of continental rift evolution is a significant challenge. To address this issue, we analyzed the morphologies and alignments of >1500 volcanic cones to infer the distribution and trends of upper crustal dikes in various rift basins across the East African Rift (EAR). Cone lineament data reveal along‐axis variations in the distribution and geometries of dike intrusions as a result of changing tectonomagmatic conditions. In younger (<10 Ma) basins of the North Tanzanian Divergence, dikes are largely restricted to zones of rift‐oblique faulting between major rift segments, referred to here as transfer zones. Cone lineament trends are highly variable, resulting from the interplay between (1) the regional stress field, (2) local magma‐induced stress fields, and (3) stress rotations related to mechanical interactions between rift segments. We find similar cone lineament trends in transfer zones in the western branch of the EAR, such as the Virunga Province, Democratic Republic of the Congo. The distributions and orientations of upper crustal dikes in the eastern branch of the EAR vary during continental rift evolution. In early‐stage rifts (<10 Ma), upper crustal dikes play a limited role in accommodating extension, as they are confined to areas in and around transfer zones. In evolved rift basins (>10 Ma) in Ethiopia and the Kenya Rift, rift‐parallel dikes accommodate upper crustal extension along the full length of the basin.
River geochemistry, chemical weathering, and atmospheric CO2 consumption rates in the Virunga Volcanic Province (East Africa)
Authors: Balagizi Charles M. , Darchambeau François , Bouillon Steven , Yalire Mathieu M. , Lambert Thibault , Borges Alberto V.
Published: July 2015

We report a water chemistry data set from 13 rivers of the Virunga Volcanic Province (VVP) (Democratic Republic of Congo), sampled between December 2010 and February 2013. Most parameters showed no pronounced seasonal variation, whereas their spatial variation suggests a strong control by lithology, soil type, slope, and vegetation. High total suspended matter (289–1467 mg L−1) was recorded in rivers in the Lake Kivu catchment, indicating high soil erodibility, partly as a consequence of deforestation and farming activities. Dissolved and particulate organic carbon (DOC and POC) were lower in rivers from lava fields, and higher in nonvolcanic subcatchments. Stable carbon isotope signatures (δ13C) of POC and DOC mean δ13C of −22.5‰ and −23.5‰, respectively, are the first data to be reported for the highland of the Congo River basin and showed a much higher C4 contribution than in lowland areas. Rivers of the VVP were net sources of CH4 to the atmosphere (4–5052 nmol L−1). Most rivers show N2O concentrations close to equilibrium, but some rivers showed high N2O concentrations related to denitrification in groundwaters. δ13C signatures of dissolved inorganic carbon suggested magmatic CO2 inputs to aquifers/soil, which could have contributed to increase basalt weathering rates. This magmatic CO2‐mediated basalt weathering strongly contributed to the high major cation concentrations and total alkalinity. Thus, chemical weathering (39.0–2779.9 t km−2 yr−1) and atmospheric CO2 consumption (0.4–37.0 × 106 mol km−2 yr−1) rates were higher than previously reported in the literature for basaltic terrains.
Integrated seismic source model of the 2015 Gorkha, Nepal, earthquake
Authors: Yagi Yuji , Okuwaki Ryo
Published: July 2015

We compared spatiotemporal slip‐rate and high‐frequency (around 1 Hz) radiation distributions from teleseismic P wave data to infer the seismic rupture process of the 2015 Gorkha, Nepal, earthquake. For these estimates, we applied a novel waveform inversion formulation that mitigates the effect of Green's functions uncertainty and a hybrid backprojection method that mitigates contamination by depth phases. Our model showed that the dynamic rupture front propagated eastward from the hypocenter at 3.0 km/s and triggered a large‐slip event centered about 50 km to the east. It also showed that the large‐slip event included a rapid rupture acceleration event and an irregular deceleration of rupture propagation before the rupture termination. Heterogeneity of the stress drop or fracture energy in the eastern part of the rupture area, where aftershock activity was high, inhibited rupture growth. High‐frequency radiation sources tended to be in the deeper part of the large‐slip area, which suggests that heterogeneity of the stress drop or fracture energy there may have contributed to the damage in and around Kathmandu.
Effects of subgrid‐scale snow thickness variability on radiative transfer in sea ice
Authors: Abraham Carsten , Steiner Nadja , Monahan Adam , Michel Christine
Published: July 2015

Snow is a principal factor in controlling heat and light fluxes through sea ice. With the goal of improving radiative and heat flux estimates through sea ice in regional and global models without the need of detailed snow property descriptions, a new parameterization including subgrid‐scale snow thickness variability is presented. One‐parameter snow thickness distributions depending only on the gridbox‐mean snow thickness are introduced resulting in analytical solutions for the fluxes of heat and light through the snow layer. As the snowpack melts, these snow thickness distributions ensure a smooth seasonal transition of the light field under sea ice. Spatially homogenous melting applied to an inhomogeneous distribution of snow thicknesses allows the appearance of bare sea ice areas and melt ponds before all snow has melted. In comparison to uniform‐thickness snow used in previous models, the bias in the under sea‐ice light field is halved with this parameterization. Model results from a one‐dimensional ocean turbulence model coupled with a thermodynamic sea ice model are compared to observations near Resolute in the Canadian High Arctic. The simulations show substantial improvements not only to the light field at the sea ice base which will affect ice algal growth but also to the sea ice and seasonal snowpack evolution. During melting periods, the snowpack can survive longer while sea ice thickness starts to reduce earlier.
Variability of Labrador Sea Water transported through Flemish Pass during 1993–2013
Authors: Schneider Linn , Kieke Dagmar , Jochumsen Kerstin , Colbourne Eugene , Yashayaev Igor , Steinfeldt Reiner , Varotsou Eirini , Serra Nuno , Rhein Monika
Published: July 2015

Flemish Pass, located at the western subpolar margin, is a passage (sill depth 1200 m) that is constrained by the Grand Banks and the underwater plateau Flemish Cap. In addition to the Deep Western Boundary Current (DWBC) pathway offshore of Flemish Cap, Flemish Pass represents another southward transport pathway for two modes of Labrador Sea Water (LSW), the lightest component of North Atlantic Deep Water carried with the DWBC. This pathway avoids potential stirring regions east of Flemish Cap and deflection into the interior North Atlantic. Ship‐based velocity measurements between 2009 and 2013 at 47°N in Flemish Pass and in the DWBC east of Flemish Cap revealed a considerable southward transport of Upper LSW through Flemish Pass (15–27%, −1.0 to −1.5 Sv). About 98% of the denser Deep LSW were carried around Flemish Cap as Flemish Pass is too shallow for considerable transport of Deep LSW. Hydrographic time series from ship‐based measurements show a significant warming of 0.3°C/decade and a salinification of 0.03/decade of the Upper LSW in Flemish Pass between 1993 and 2013. Almost identical trends were found for the evolution in the Labrador Sea and in the DWBC east of Flemish Cap. This indicates that the long‐term hydrographic variability of Upper LSW in Flemish Pass as well as in the DWBC at 47°N is dominated by changes in the Labrador Sea, which are advected southward. Fifty years of numerical ocean model simulations in Flemish Pass suggest that these trends are part of a multidecadal cycle.
Evaluation of MODIS aerosol retrieval algorithms over the Beijing‐Tianjin‐Hebei region during low to very high pollution events
Authors: Bilal Muhammad , Nichol Janet E.
Published: July 2015

This study evaluates the performance of different MODerate resolution Imaging Spectroradiometer (MODIS) aerosol algorithms during fine particle pollution events over the Beijing‐Tianjin‐Hebei region using Aerosol Robotic Network aerosol optical depth (AOD). These algorithms include the Deep Blue (DB) Collection 5.1 (C5) and Collection 6 (C6) algorithms at 10 km resolution, the Dark Target (DT) C5 and C6 algorithms at 10 km, the DT C6 algorithm at 3 km, and the Simplified Aerosol Retrieval Algorithm (SARA) at 500 m, 3 km, and 10 km resolutions. The DB C6 retrievals have 34–39% less uncertainties, 2–3 times smaller root‐mean‐square error (RMSE), and 3–4 times smaller mean absolute error (MAE) than DB C5 retrievals. The DT C6 has 4–8% lower bias, 4–12% less overestimation, and smaller RMSE and MAE errors than DT C5. Due to underestimation of surface reflectance and the use of inappropriate aerosol schemes, 87–89% of the collocations of the DT C6 at 3 km fall above the expected error (EE), with overestimation of 64–79% which is 15–27% higher than that for the DT C6 at 10 km. The results suggest that the DT C6 at 3 km resolution is less reliable than that at 10 km. The SARA AOD has small RMSE and MAE errors with 90–96% of the collocations falling within the EE. Overall, the SARA showed 15–16% less uncertainty than the DB C6 (10 km), 69–72% less than the DT C6 (10 km), and 79–83% less than the DT C6 (3 km) retrievals.
A hybrid framework for assessing socioeconomic drought: Linking climate variability, local resilience, and demand
Authors: Mehran Ali , Mazdiyasni Omid , AghaKouchak Amir
Published: July 2015

Socioeconomic drought broadly refers to conditions whereby the water supply cannot satisfy the demand. Most previous studies describe droughts based on large‐scale meteorological/hydrologic conditions, ignoring the demand and local resilience to cope with climate variability. Reservoirs provide resilience against climatic extremes and play a key role in water supply and demand management. Here we outline a unique multivariate approach as a measure of socioeconomic drought, termed Multivariate Standardized Reliability and Resilience Index (MSRRI). The model combines information on the inflow and reservoir storage relative to the demand. MSRRI combines (I) a “top‐down” approach that focuses on processes/phenomena that cannot be simply controlled or altered by decision makers, such as climate change and variability, and (II) a “bottom‐up” methodology that represents the local resilience and societal capacity to respond or adapt to droughts. MSRRI is based on a nonparametric multivariate distribution function that links inflow‐demand reliability indicator to water storage resilience indicator. These indicators are used to assess socioeconomic drought during the Australian Millennium drought (1998–2010) and the 2011–2014 California drought. The results show that MSRRI is superior to univariate indices because it captures both early onset and persistence of water stress over time. The suggested framework can be applied to both individual reservoirs and a group of reservoirs in a region, and it is consistent with the currently available standardized drought indicators. MSRRI provides complementary information on socioeconomic drought development and recovery based on reservoir storage and demand that cannot be achieved from the commonly used drought indicators.
What controls the seasonal cycle of black carbon aerosols in India?
Authors: Kumar Rajesh , Barth M. C. , Pfister G. G. , Nair V. S. , Ghude Sachin D. , Ojha N.
Published: July 2015

The seasonal variability of black carbon (BC) aerosols in India is studied using high resolution (10 km) BC simulations conducted using the Weather Research and Forecasting Model coupled with Chemistry. The model reproduces the observed seasonality of surface BC fairly well over most parts of India but fails to capture the seasonality in the Himalayas and deviates from the observed BC magnitude at several sites. The errors in modeled BC are attributed to uncertainties in BC emissions and their diurnal cycle, planetary boundary layer height underestimation, and aerosol processes. Model results show distinct but opposite seasonality of BC in the lower (LT) and free troposphere (FT) with BC showing winter maximum and summer minimum in the LT and vice versa in the FT. Our analysis shows that BC seasonality is not driven by seasonality of the anthropogenic emissions but by changes in the regional meteorology through weakening of the horizontal transport and strengthening of the vertical transport of BC during summertime compared to winter. BC in both the LT and FT comes mostly from anthropogenic emissions followed by biomass burning emissions except during winter when long‐distant sources become more important in the FT. BC in the FT is significantly affected by anthropogenic emissions from all parts of India. The source‐receptor relationship changes seasonally, but the regional transport remains a significant contributor to BC loadings in the LT of India, highlighting the necessity of considering nonlocal sources along with local emissions when designing strategies for mitigating BC impacts on air quality.
Separating aerosol microphysical effects and satellite measurement artifacts of the relationships between warm rain onset height and aerosol optical depth
Authors: Zhu Yannian , Rosenfeld Daniel , Yu Xing , Li Zhanqing
Published: July 2015

The high resolution (375 m) of the Visible Infrared Imaging Radiometer Suite on board the Suomi National Polar‐Orbiting Partnership satellite allows retrieving relatively accurately the vertical evolution of convective cloud drop effective radius (re) with height or temperature. A tight relationship is found over SE Asia and the adjacent seas during summer between the cloud‐free aerosol optical depth (AOD) and the cloud thickness required for the initiation of warm rain, as represented by the satellite‐retrieved cloud droplet re of 14 µm, for a subset of conditions that minimize measurement artifacts. This cloud depth (ΔT14) is parameterized as the difference between the cloud base temperature and the temperature at the height where re exceeds 14 µm (T14). For a unit increase of AOD, the height of rain initiation is increased by about 5.5 km. The concern of data artifacts due to the increase in AOD near clouds was mitigated by selecting only scenes with cloud fraction (CF) < 0.1. For CF > 0.1 and ΔT14 > ~20°C, the increase of ΔT14 gradually levels off with further increase of AOD, possibly because the AOD is enhanced by aerosol upward transport and detrainment through the clouds below the T14 isotherm. The bias in the retrieved re due to the different geometries of solar illumination was also quantified. It was shown that the retrievals are valid only for backscatter views or when avoiding scenes with significant amount of cloud self‐shadowing. These artifacts might have contributed to past reported relationships between cloud properties and AOD.
Methane release from pingo‐like features across the South Kara Sea shelf, an area of thawing offshore permafrost
Authors: Serov Pavel , Portnov Alexey , Mienert Jurgen , Semenov Peter , Ilatovskaya Polina
Published: July 2015

The Holocene marine transgression starting at ~19 ka flooded the Arctic shelves driving extensive thawing of terrestrial permafrost. It thereby promoted methanogenesis within sediments, the dissociation of gas hydrates, and the release of formerly trapped gas, with the accumulation in pressure of released methane eventually triggering blowouts through weakened zones in the overlying and thinned permafrost. Here we present a range of geophysical and chemical scenarios for the formation of pingo‐like formations (PLFs) leading to potential blowouts. Specifically, we report on methane anomalies from the South Kara Sea shelf focusing on two PLFs imaged from high‐resolution seismic records. A variety of geochemical methods are applied to study concentrations and types of gas, its character, and genesis. PLF 1 demonstrates ubiquitously low‐methane concentrations (14.2–55.3 ppm) that are likely due to partly unfrozen sediments with an ice‐saturated internal core reaching close to the seafloor. In contrast, PLF 2 reveals anomalously high‐methane concentrations of >120,000 ppm where frozen sediments are completely absent. The methane in all recovered samples is of microbial and not of thermogenic origin from deep hydrocarbon sources. However, the relatively low organic matter content (0.52–1.69%) of seafloor sediments restricts extensive in situ methane production. As a consequence, we hypothesize that the high‐methane concentrations at PLF 2 are due to microbial methane production and migration from a deeper source.