bluuebunny/crossref_metadata_2025 huggingface dataset:
Classification of Lower Extremity Movement Patterns Based on Visual Assessment: Reliability and Correlation With 2-Dimensional Video Analysis
Authors: Harris-Hayes Marcie , Steger-May Karen , Koh Christine , Royer Nat K. , Graci Valentina , Salsich Gretchen B.
Published: June 2014

Context:

Abnormal movement patterns have been implicated in lower extremity injury. Reliable, valid, and easily implemented assessment methods are needed to examine existing musculoskeletal disorders and investigate predictive factors for lower extremity injury.

Objective:

To determine the reliability of experienced and novice testers in making visual assessments of lower extremity movement patterns and to characterize the construct validity of the visual assessments.

Design:

Cross-sectional study.

Setting:

University athletic department and research laboratory.

Patients or Other Participants:

Convenience sample of 30 undergraduate and graduate students who regularly participate in athletics (age = 19.3 ± 4.5 years). Testers were 2 experienced physical therapists and 1 novice postdoctoral fellow (nonclinician).

Main Outcome Measure(s):

We took videos of 30 athletes performing the single-legged squat. Three testers observed the videos on 2 occasions and classified the lower extremity movement as dynamic valgus, no change, or dynamic varus. The classification was based on the estimated change in frontal-plane projection angle (FPPA) of the knee from single-legged stance to maximum single-legged squat depth. The actual FPPA change was measured quantitatively. We used percentage agreement and weighted κ to examine tester reliability and to determine construct validity of the visual assessment.

Results:

The κ values for intratester and intertester reliability ranged from 0.75 to 0.90, indicating substantial to excellent reliability. Percentage agreement between the visual assessment and the quantitative FPPA change category was 90%, with a κ value of 0.85.

Conclusions:

Visual assessments were made reliably by experienced and novice testers. Additionally, movement-pattern categories based on visual assessments were in excellent agreement with objective methods to measure FPPA change. Therefore, visual assessments can be used in the clinic to assess movement patterns associated with musculoskeletal disorders and in large epidemiologic studies to assess the association between lower extremity movement patterns and musculoskeletal injury.
A Generalizability Theory Study of Athletic Taping Using the Technical Skill Assessment Instrument
Authors: Lafave Mark R. , Butterwick Dale J.
Published: June 2014

Context:

Athletic taping skills are highly valued clinical competencies in the athletic therapy and training profession. The Technical Skill Assessment Instrument (TSAI) has been content validated and tested for intrarater reliability.

Objective:

To test the reliability of the TSAI using a more robust measure of reliability, generalizability theory, and to hypothetically and mathematically project the optimal number of raters and scenarios to reliably measure athletic taping skills in the future.

Setting:

Mount Royal University.

Design:

Observational study.

Patients or Other Participants:

A total of 29 university students (8 men, 21 women; age = 20.79 ± 1.59 years) from the Athletic Therapy Program at Mount Royal University.

Intervention(s):

Participants were allowed 10 minutes per scenario to complete prophylactic taping for a standardized patient presenting with (1) a 4-week-old second-degree ankle sprain and (2) a thumb that had been hyperextended. Two raters judged student performance using the TSAI.

Main Outcome Measure(s):

Generalizability coefficients were calculated using variance scores for raters, participants, and scenarios. A decision study was calculated to project the optimal number of raters and scenarios to achieve acceptable levels of reliability. Generalizability coefficients were interpreted the same as other reliability coefficients, with 0 indicating no reliability and 1.0 indicating perfect reliability.

Results:

The result of our study design (2 raters, 1 standardized patient, 2 scenarios) was a generalizability coefficient of 0.67. Decision study projects indicated that 4 scenarios were necessary to reliably measure athletic taping skills.

Conclusions:

We found moderate reliability coefficients. Researchers should include more scenarios to reliably measure athletic taping skills. They should also focus on the development of evidence-based practice guidelines and standards of athletic taping and should test those standards using a psychometrically sound instrument, such as the TSAI.
Electrolyte and Plasma Responses After Pickle Juice, Mustard, and Deionized Water Ingestion in Dehydrated Humans
Authors: Miller Kevin C.
Published: June 2014

Context:

Some athletes ingest pickle juice (PJ) or mustard to treat exercise-associated muscle cramps (EAMCs). Clinicians warn against this because they are concerned it will exacerbate exercise-induced hypertonicity or cause hyperkalemia. Few researchers have examined plasma responses after PJ or mustard ingestion in dehydrated, exercised individuals.

Objective:

To determine if ingesting PJ, mustard, or deionized water (DIW) while hypohydrated affects plasma sodium (Na+) concentration ([Na+]p), plasma potassium (K+) concentration ([K+]p), plasma osmolality (OSMp), or percentage changes in plasma volume or Na+ content.

Design:

Crossover study.

Setting:

Laboratory.

Patients or Other Participants:

A total of 9 physically active, nonacclimated individuals (age = 25 ± 2 years, height = 175.5 ± 9.0 cm, mass = 78.6 ± 13.8 kg).

Intervention(s):

Participants exercised vigorously for 2 hours (temperature = 37°C ± 1°C, relative humidity = 24% ± 4%). After a 30-minute rest, a baseline blood sample was collected, and they ingested 1 mL/kg body mass of PJ or DIW. For the mustard trial, participants ingested a mass of mustard containing a similar amount of Na+ as for the PJ trial. Postingestion blood samples were collected at 5, 15, 30, and 60 minutes.

Main Outcome Measure(s):

The dependent variables were [Na+]p, [K+]p, OSMp, and percentage change in plasma Na+ content and plasma volume.

Results:

Participants became 2.9% ± 0.6% hypohydrated and lost 96.8 ± 27.1 mmol (conventional unit = 96.8 ± 27.1 mEq) of Na+, 8.4 ± 2 mmol (conventional unit = 8.4 ± 2 mEq) of K+, and 2.03 ± 0.44 L of fluid due to exercise-induced sweating. They ingested approximately 79 mL of PJ or DIW or 135.24 ± 22.8 g of mustard. Despite ingesting approximately 1.5 g of Na+ in the PJ and mustard trials, no changes occurred within 60 minutes postingestion for [Na+]p, [K+]p, OSMp, or percentage changes in plasma volume or Na+ content (P > .05).

Conclusions:

Ingesting a small bolus of PJ or large mass of mustard after dehydration did not exacerbate exercise-induced hypertonicity or cause hyperkalemia. Consuming small volumes of PJ or mustard did not fully replenish electrolytes and fluid losses. Additional research on plasma responses pre-ingestion and postingestion to these treatments in individuals experiencing acute EAMCs is needed.
Imaging Spectrum of Hemangioma and Vascular Malformations of the Head and Neck in Children and Adolescents
Authors: Bhat Venkatraman , Salins Paul C , Bhat Varun
Published: June 2014

Vascular lesions of the head and neck region in children constitute an interesting group of lesions that benefit immensely from imaging techniques. Imaging is essential for identification, characterization, and delineation of the extent of lesion and subsequent follow-up. Infantile hemangiomas, which are vascular tumors with a specific evolution pattern, constitute a large majority of these lesions. On the other hand, there are vascular malformations, which are anomalies of the vascular system, consisting of a range of vascular tissues associated with various flow patterns. When diagnosis is clinically evident, imaging should utilize non-radiation techniques and address the issues necessary for management. Timing and interpretation of imaging methods employed in assessing childhood vascular lesion should also take into consideration the natural history so that imaging is performed to address a specific question. This review highlights the typical appearance of a hemangioma and a group of vascular malformations of the head and neck. For descriptive purpose, an attempt has been made to group lesions into specific subsites, with each one having specific clinical significance. Cases included illustrate the spectrum of the disease ranging from classical form in young children to slightly differing manifestations of the disease in adolescents and adults. The illustrations also provide a novel way of presenting image data using volume-rendering techniques of 3D data. Multi-modality team interaction and management strategies of these complex lesions are also emphasized.
Multi-level Split Cord Malformation: Do We Need a New Classification?
Authors: Alzhrani Gmaan A , Al-Jehani Hosam M , Melançon Denis
Published: June 2014

Split cord malformations (SCMs) are thought to be rare abnormalities representing 3.8-5% of all spinal cord anomalies. The prevalence is estimated to be 1 in 5499 live births (0.02%), with a slight female predominance (1.3:1). Although the estimates of prevalence vary, Type I SCM occurs more frequently than Type II SCM. In this paper, we are reporting the clinical presentation and imaging findings of multi-level SCM in a 27-year-old male. A literature review of the embryological background of SCM and pathological hypothesis for this entity is provided. A systematic review has been conducted to identify multi-level SCM cases reported in the literature, followed by proposing a new classification system to further our understanding and management of SCMs.
Counterexample to the convexity of level sets of solutions to the mean curvature equation
Authors: Wang Xu-Jia
Published: June 2014

The convexity of level sets of solutions to the mean curvature equation is a long standing open problem. In this paper we give a counterexample to it.
Semiclassical measures for the Schrödinger equation on the torus
Authors: Anantharaman Nalini , Macià Fabricio
Published: June 2014

In this article, the structure of semiclassical measures for solutions to the linear Schrödinger equation on the torus is analysed. We show that the disintegration of such a measure on every invariant lagrangian torus is absolutely continuous with respect to the Lebesgue measure. We obtain an expression of the Radon-Nikodym derivative in terms of the sequence of initial data and show that it satisfies an explicit propagation law. As a consequence, we also prove an observability inequality, saying that the

L^2

-norm of a solution on any open subset of the torus controls the full

L^2

-norm.
Book reviews
Authors: Prijatelj Agni
Published: June 2014

Book reviews
Evaluation of a Korean version of a tool for assessing the incorporation of human factors into a medication-related decision support system: the I-MeDeSA
Authors: Cho I. , Han H. , Phansalkar S. , Bates D.W. , Lee J.
Published: June 2014

Objective: The Instrument for Evaluating Human-Factor Principles in Medication-Related Decision Support Alerts (I-MeDeSA) was developed recently in the US with a view towards improving considerations of human-factor principles when designing alerts for clinical decision support (CDS) systems. This study evaluated the generalizability of this tool, in cooperation with its authors, across cultures by applying it to a Korean system. We also examined opportunities to promote user acceptance of the system.

Methods: We developed a Korean version of the I-MeDeSA (K-I-MeDeSA) and used it to evaluate drug-drug interaction alerts in a large academic tertiary hospital in Seoul. We involved four reviewers (A, B, C, and D). Two (A and B) conducted the initial independent scoring, while the other two (C and D) performed a final review and assessed feedback from the initial reviewers. The obtained scores were compared with those from 13 previously reported CDS systems. The feedback was summarized qualitatively.

Results: The translation of the I-MeDeSA had excellent interrater agreement in terms of face validity (scale-level content validity index = 0.95). The system’s K-I-MeDeSA score was 10 out of 26, with a good agreement between reviewers (κ = 0.77), which showed a lack of human-factor considerations. The reviewers readily identified two of the nine principles that needed primary improvement: prioritization and text-based information. The reviewers also expressed difficulty judging the following four principles: alarm philosophy, visibility, color, and learnability and confusability. Conclusion: The K-I-MeDeSA was semantically and operationally equivalent to the original tool. Only minor cultural problems were identified, leading the reviewers to suggest the need for clarification of certain words plus a more detailed description of the tool’s rationale and exemplars. Further evaluation is needed to empirically assess whether the implementation of changes in an electronic health record system could improve the adoption of CDS alerts.

Citation: Cho I, Lee J, Han H, Phansalkar S, Bates DW. Evaluation of a Korean version of a tool for assessing the incorporation of human factors into a medicationrelated decision support system: the I-MeDeSA. Appl Clin Inf 2014; 5: 571–588 http://dx.doi.org/10.4338/ACI-01-RA-0005
Development and validation of a computer-based algorithm to identify foreign-born patients with HIV infection from the electronic medical record
Authors: Triant V. , Losina E. , Keefe K. , Freedberg K. , Regan S. , Levison J.
Published: June 2014

Objective: To develop and validate an efficient and accurate method to identify foreign-born patients from a large patient data registry in order to facilitate population-based health outcomes research.

Methods: We developed a three-stage algorithm for classifying foreign-born status in HIV-infected patients receiving care in a large US healthcare system (January 1, 2001-March 31, 2012) (n = 9,114). In stage 1, we classified those coded as non-English language speaking as foreign-born. In stage 2, we searched free text electronic medical record (EMR) notes of remaining patients for keywords associated with place of birth and language spoken. Patients without keywords were classified as US-born. In stage 3, we retrieved and reviewed a 50-character text window around the keyword (i.e. token) for the remaining patients. To validate the algorithm, we performed a chart review and asked all HIV physicians (n = 37) to classify their patients (n = 957).We calculated algorithm sensitivity and specificity.

Results: We excluded 160/957 because physicians indicated the patient was not HIV-infected (n = 54), “not my patient” (n = 103), or had unknown place of birth (n = 3), leaving 797 for analysis. In stage 1, providers agreed that 71/95 foreign language speakers were foreign-born. Most disagreements (23/24) involved patients born in Puerto Rico. In stage 2, 49/50 patients without keywords were classified as US-born by chart review. In stage 3, token review correctly classified 55/60 patients (92%), with 93% (CI: 84.4, 100%) sensitivity and 90% (CI: 74.3, 100%) specificity compared with full chart review. After application of the three-stage algorithm, 2,102/9,114 (23%) patients were classified as foreign-born. When compared against physician response, estimated sensitivity of the algorithm was 94% (CI: 90.9, 97.2%) and specificity 92% (CI: 89.7, 94.1%), with 92% correctly classified.

Conclusion: A computer-based algorithm classified foreign-born status in a large HIV-infected cohort efficiently and accurately. This approach can be used to improve EMR-based outcomes research.

Citation: Levison J, Triant V, Losina E, Keefe K, Freedberg K, Regan S. Development and validation of a computer-based algorithm to identify foreign-born patients with HIV infection from the electronic medical record. Appl Clin Inf 2014; 5: 557–570 http://dx.doi.org/10.4338/ACI-02-RA-0013
Gynecological Tumors Image using High Definition Ultrasound (HDlive US)
Authors: Raga Francisco , Bonilla Francisco , Bonilla-Musoles Fernando , Castillo Juan Carlos , Luna Oscar Caballero
Published: June 2014

Abdominal and/or vaginal two-dimensional (2D) and threedimensional (3D) ultrasound (US) are the ‘gold standard’ technology on which diagnosis and control of gynecological tumors depend.

In recent years a series of software that initially generated enormous interest, have been introduced to improve 2D/3D US image quality and diagnostic accuracy. Many of them have shown limited interests.

The last one and the most interesting is HDlive which incorporates a movable virtual adjustable light that, as it penetrates, produces selective illumination with respective shadows that result from the structures where light is reflected. This combination of lights and shadows results in spectacular images which are much more real than those obtained with conventional 3D US.

This note simply pretends to show the quality of images obtained in cases of gynecological tumors using this easy-tohandle high definition ultrasound technology.

How to cite this article

Bonilla-Musoles F, Raga F, Bonilla F Jr, Castillo JC, Luna OC. Gynecological Tumors Image using High Definition Ultrasound (HDlive US). Donald School J Ultrasound Obstet Gynecol 2014;8(2):155-163.
Cardiac Tumors in the Neonatal Period: Clinical Features and Echocardiographic Evaluation
Authors: Stamatian Florin , Kovacs Tunde , Hăşmăşanu Monica , Opriţa Simona , Andreica Sorin , Mátyás Melinda , Decean Estera , Zaharie Gabriela
Published: June 2014

Introduction

Primary cardiac tumors are rare in the fetal and neonatal period (0.0017-0.28%), but considerably more frequent than the metastatic ones; most of them are benign. The objective of this study was to analyze the clinical and echocardiographic features of cardiac tumors during the neonatal period.

Case presentations

In the period of 6 years (2007-2012), we diagnosed five newborns with cardiac tumors of which two newborns with left ventricle tumors suggestive of rhabdomyomas, both diagnosed in utero; a newborn with multiple heart and brain tumors, suggestive of tuberous sclerosis, who died after 24 days; a newborn with tricuspid valve papillary fibroelastoma, hemodynamically stable during the monitoring; and a newborn of the mother with high-risk pregnancy with a single right atrial tumor.

Conclusion

Cardiac tumors are rare but have good prognosis when not accompanied by arrhythmias or hemodynamic changes. Echocardiographic evaluation is an effective method for the diagnosis and monitoring of patients with cardiac tumors.

How to cite this article

Hăşmăşanu M, Opriţa S, Kovacs T, Andreica S, Mátyás M, Decean E, Stamatian F, Zaharie G. Cardiac Tumors in the Neonatal Period: Clinical Features and Echocardiographic Evaluation. Donald School J Ultrasound Obstet Gynecol 2014;8(2):201-207.
Outcome of a Rare Case of Fetal Solitary Cardiac Rhabdomyoma not Associated with Tuberous Sclerosis
Authors: Shailaja Nageshu , Namrata Kulkarni , Krishna Lingegowda , LNU Vanishree , Bhat BS , Kirtan Krishna , Swathi Gunda
Published: June 2014

At 19 weeks 6 days ultrasonography of a 31-year-old G2P1L1 revealed a small echogenic area seen in the subvalvular apparatus of the mitral valve (anterior mitral leaflet) suggestive of cardiac rhabdomyoma (CR). At 28 weeks of gestation there was mild increase in the size of the CR (13 × 6 mm). There was no evidence of hemodynamic compromise. The interval growth of the fetus was satisfactory. The family tree of three generations was examined and revealed no evidence of Tuberous Sclerosis. She delivered a live 34 weeks 2.2 kg male baby with 8 and 9 Apgar scores at 5 and 10 minutes respectively. Baby suddenly developed cyanosis and died 24 hours after birth. The fetal autopsy confirmed the diagnosis of CR. Genetic analysis of neonatal blood revealed no evidence of TSC mutation suggestive of tuberous sclerosis.

How to cite this article

Shailaja N, Namrata K, Krishna L, Vanishree, Bhat BS, Kirtan K, Swathi G. Outcome of a Rare Case of Fetal Solitary Cardiac Rhabdomyoma not Associated with Tuberous Sclerosis. Donald School J Ultrasound Obstet Gynecol 2014;8(2):226-228.
Assimilation of atmospheric methane products into the MACC-II system: from SCIAMACHY to TANSO and IASI
Authors: Massart S. , Agusti-Panareda A. , Aben I. , Butz A. , Chevallier F. , Crevoisier C. , Engelen R. , Frankenberg C. , Hasekamp O.
Published: June 2014

Abstract. The Monitoring Atmospheric Composition and Climate Interim Implementation (MACC-II) delayed-mode (DM) system has been producing an atmospheric methane (CH4) analysis 6 months behind real time since June 2009. This analysis used to rely on the assimilation of the CH4 product from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) instrument onboard Envisat. Recently the Laboratoire de Météorologie Dynamique (LMD) CH4 products from the Infrared Atmospheric Sounding Interferometer (IASI) and the SRON Netherlands Institute for Space Research CH4 products from the Thermal And Near-infrared Sensor for carbon Observation (TANSO) were added to the DM system. With the loss of Envisat in April 2012, the DM system now has to rely on the assimilation of methane data from TANSO and IASI. This paper documents the impact of this change in the observing system on the methane tropospheric analysis. It is based on four experiments: one free run and three analyses from respectively the assimilation of SCIAMACHY, TANSO and a combination of TANSO and IASI CH4 products in the MACC-II system. The period between December 2010 and April 2012 is studied. The SCIAMACHY experiment globally underestimates the tropospheric methane by 35 part per billion (ppb) compared to the HIAPER Pole-to-Pole Observations (HIPPO) data and by 28 ppb compared the Total Carbon Column Observing Network (TCCON) data, while the free run presents an underestimation of 5 ppb and 1 ppb against the same HIPPO and TCCON data, respectively. The assimilated TANSO product changed in October 2011 from version v.1 to version v.2.0. The analysis of version v.1 globally underestimates the tropospheric methane by 18 ppb compared to the HIPPO data and by 15 ppb compared to the TCCON data. In contrast, the analysis of version v.2.0 globally overestimates the column by 3 ppb. When the high density IASI data are added in the tropical region between 30° N and 30° S, their impact is mainly positive but more pronounced and effective when combined with version v.2.0 of the TANSO products. The resulting analysis globally underestimates the column-averaged dry-air mole fractions of methane (xCH4) just under 1 ppb on average compared to the TCCON data, whereas in the tropics it overestimates xCH4 by about 3 ppb. The random error is estimated to be less than 7 ppb when compared to TCCON data.
Organic aerosol components derived from 25 AMS data sets across Europe using a consistent ME-2 based source apportionment approach
Authors: Crippa M. , Canonaco F. , Lanz V. A. , Äijälä M. , Allan J. D. , Carbone S. , Capes G. , Ceburnis D. , Dall'Osto M. , Day D. A. , DeCarlo P. F. , Ehn M. , Eriksson A. , Freney E. , Hildebrandt Ruiz L. , Hillamo R. , Jimenez J. L. , Junninen H. , Kiendler-Scharr A. , Kortelainen A.-M. , Kulmala M. , Laaksonen A. , Mensah A. A. , Mohr C. , Nemitz E. , O'Dowd C. , Ovadnevaite J. , Pandis S. N. , Petäjä T. , Poulain L. , Saarikoski S. , Sellegri K. , Swietlicki E. , Tiitta P. , Worsnop D. R. , Baltensperger U. , Prévôt A. S. H.
Published: June 2014

Abstract. Organic aerosols (OA) represent one of the major constituents of submicron particulate matter (PM1) and comprise a huge variety of compounds emitted by different sources. Three intensive measurement field campaigns to investigate the aerosol chemical composition all over Europe were carried out within the framework of the European Integrated Project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI) and the intensive campaigns of European Monitoring and Evaluation Programme (EMEP) during 2008 (May–June and September–October) and 2009 (February–March). In this paper we focus on the identification of the main organic aerosol sources and we define a standardized methodology to perform source apportionment using positive matrix factorization (PMF) with the multilinear engine (ME-2) on Aerodyne aerosol mass spectrometer (AMS) data. Our source apportionment procedure is tested and applied on 25 data sets accounting for two urban, several rural and remote and two high altitude sites; therefore it is likely suitable for the treatment of AMS-related ambient data sets. For most of the sites, four organic components are retrieved, improving significantly previous source apportionment results where only a separation in primary and secondary OA sources was possible. Generally, our solutions include two primary OA sources, i.e. hydrocarbon-like OA (HOA) and biomass burning OA (BBOA) and two secondary OA components, i.e. semi-volatile oxygenated OA (SV-OOA) and low-volatility oxygenated OA (LV-OOA). For specific sites cooking-related (COA) and marine-related sources (MSA) are also separated. Finally, our work provides a large overview of organic aerosol sources in Europe and an interesting set of highly time resolved data for modeling purposes.
Impact of tropical land convection on the water vapour budget in the tropical tropopause layer
Authors: Carminati F. , Ricaud P. , Pommereau J.-P. , Rivière E. , Khaykin S. , Attié J.-L. , Warner J.
Published: June 2014

Abstract. The tropical deep overshooting convection is known to be most intense above continental areas such as South America, Africa, and the maritime continent. However, its impact on the tropical tropopause layer (TTL) at global scale remains debated. In our analysis, we use the 8-year Microwave Limb Sounder (MLS) water vapour (H2O), cloud ice-water content (IWC), and temperature data sets from 2005 to date, to highlight the interplays between these parameters and their role in the water vapour variability in the TTL, and separately in the northern and southern tropics. In the tropical upper troposphere (177 hPa), continents, including the maritime continent, present the night-time (01:30 local time, LT) peak in the water vapour mixing ratio characteristic of the H2O diurnal cycle above tropical land. The western Pacific region, governed by the tropical oceanic diurnal cycle, has a daytime maximum (13:30 LT). In the TTL (100 hPa) and tropical lower stratosphere (56 hPa), South America and Africa differ from the maritime continent and western Pacific displaying a daytime maximum of H2O. In addition, the relative amplitude between day and night is found to be systematically higher by 5–10% in the southern tropical upper troposphere and 1–3% in the TTL than in the northern tropics during their respective summer, indicative of a larger impact of the convection on H2O in the southern tropics. Using a regional-scale approach, we investigate how mechanisms linked to the H2O variability differ in function of the geography. In summary, the MLS water vapour and cloud ice-water observations demonstrate a clear contribution to the TTL moistening by ice crystals overshooting over tropical land regions. The process is found to be much more effective in the southern tropics. Deep convection is responsible for the diurnal temperature variability in the same geographical areas in the lowermost stratosphere, which in turn drives the variability of H2O.
Statistical modelling of collocation uncertainty in atmospheric thermodynamic profiles
Authors: Fassò A. , Ignaccolo R. , Madonna F. , Demoz B. B. , Franco-Villoria M.
Published: June 2014

Abstract. The quantification of measurement uncertainty of atmospheric parameters is a key factor in assessing the uncertainty of global change estimates given by numerical prediction models. One of the critical contributions to the uncertainty budget is related to the collocation mismatch in space and time among observations made at different locations. This is particularly important for vertical atmospheric profiles obtained by radiosondes or lidar. In this paper we propose a statistical modelling approach capable of explaining the relationship between collocation uncertainty and a set of environmental factors, height and distance between imperfectly collocated trajectories. The new statistical approach is based on the heteroskedastic functional regression (HFR) model which extends the standard functional regression approach and allows a natural definition of uncertainty profiles. Along this line, a five-fold decomposition of the total collocation uncertainty is proposed, giving both a profile budget and an integrated column budget. HFR is a data-driven approach valid for any atmospheric parameter, which can be assumed smooth. It is illustrated here by means of the collocation uncertainty analysis of relative humidity from two stations involved in the GCOS reference upper-air network (GRUAN). In this case, 85% of the total collocation uncertainty is ascribed to reducible environmental error, 11% to irreducible environmental error, 3.4% to adjustable bias, 0.1% to sampling error and 0.2% to measurement error.
Quantifying the value of redundant measurements at GRUAN sites
Authors: Madonna F. , Rosoldi M. , Güldner J. , Haefele A. , Kivi R. , Cadeddu M. P. , Sisterson D. , Pappalardo G.
Published: June 2014

Abstract. The potential for measurement redundancy to reduce uncertainty in atmospheric variables has not been investigated comprehensively for climate observations. We evaluated the usefulness of entropy and mutual correlation concepts, as defined in information theory, for quantifying random uncertainty and redundancy in time series of atmospheric water vapor provided by five highly instrumented GRUAN (GCOS [Global Climate Observing System] Reference Upper-Air Network) Stations in 2010–2012. Results show that the random uncertainties for radiosonde, frost-point hygrometer, Global Positioning System, microwave and infrared radiometers, and Raman lidar measurements differed by less than 8%. Comparisons of time series of the Integrated Water Vapor (IWV) content from ground-based remote sensing instruments with in situ soundings showed that microwave radiometers have the highest redundancy and therefore the highest potential to reduce random uncertainty of IWV time series estimated by radiosondes. Moreover, the random uncertainty of a time series from one instrument should be reduced of ~ 60% by constraining the measurements with those from another instrument. The best reduction of random uncertainty resulted from conditioning of Raman lidar measurements with microwave radiometer measurements. Specific instruments are recommended for atmospheric water vapor measurements at GRUAN sites. This approach can be applied to the study of redundant measurements for other climate variables.
Interaction of ice sheets and climate during the past 800 000 years
Authors: Stap L. B. , van de Wal R. S. W. , de Boer B. , Bintanja R. , Lourens L. J.
Published: June 2014

Abstract. During the Cenozoic, land ice and climate have interacted on many different time scales. On long time scales, the effect of land ice on global climate and sea level is mainly set by large ice sheets on North America, Eurasia, Greenland and Antarctica. The climatic forcing of these ice sheets is largely determined by the meridional temperature profile resulting from radiation and greenhouse gas (GHG) forcing. As response, the ice sheets cause an increase in albedo and surface elevation, which operates as a feedback in the climate system. To quantify the importance of these climate-land ice processes, a zonally-averaged energy balance climate model is coupled to five one-dimensional ice-sheet models, representing the major ice sheets. In this study, we focus on the transient simulation of the past 800 000 years, where a high-confidence CO2-record from ice cores samples is used as input in combination with Milankovitch radiation changes. We obtain simulations of atmospheric temperature, ice volume and sea level, that are in good agreement with recent proxy-data reconstructions. We examine long-term climate-ice sheet interactions by a comparison of simulations with uncoupled and coupled ice sheets. We show that these interactions amplify global temperature anomalies by up to a factor 2.6, and that they increase polar amplification by 94%. We demonstrate that, on these long time scales, the ice-albedo feedback has a larger and more global influence on the meridional atmospheric temperature profile than the surface-height temperature feedback. Furthermore, we assess the influence of CO2 and insolation, by performing runs with one or both of these variables held constant. We find that atmospheric temperature is controlled by a complex interaction of CO2 and insolation, and both variables serve as thresholds for Northern Hemispheric glaciation.
Continued increase in atmospheric CO2 seasonal amplitude in the 21st century projected by the CMIP5 Earth System Models
Authors: Zhao F. , Zeng N.
Published: June 2014

Abstract. Superimposed on the continued increase in the atmospheric CO2 concentration is a prominent seasonal cycle. Ground-based and aircraft-based observation records show that the amplitude of this seasonal cycle has increased. Will this trend continue into future? In this paper, we analyzed simulations for historical (1850–2005) and future (RCP8.5, 2006–2100) periods produced by 10 Earth System Models participating the Fifth Phase of the Coupled Model Intercomparison Project (CMIP5). Our results show a model consensus that the increase of CO2 seasonal amplitude continues throughout the 21st century. The seasonal amplitude of the multi-model global mean detrended CO2 increases from 1.6 ppm during 1961–1970 to 2.7 ppm during 2081–2090, and the mean relative amplitude increases by 62 ± 19%. This increase is dominated by a 68 ± 25% increase from Net Biosphere Production (NBP). We then show the increase of NBP amplitude mainly comes from enhanced ecosystem uptake during Northern Hemisphere growing season under future CO2 and temperature conditions. Separate analyses on net primary production and respiration reveal that enhanced ecosystem carbon uptake contributes to about 75% of the amplitude increase. Stimulated by higher CO2 concentration and high-latitude warming, enhanced net primary production likely outcompetes increased respiration at higher temperature. Zonal distribution and the spatial pattern of NBP change suggest that regions north of 45° N dominate the amplitude increase. We also found that changes of NBP and its seasonal amplitude are significantly (R = 0.73, p < 0.05) correlated – models that simulate a stronger carbon uptake tend to show a larger change of NBP seasonal amplitude.
A technique for generating consistent ice sheet initial conditions for coupled ice sheet/climate models
Authors: Fyke J. G. , Sacks W. J. , Lipscomb W. H.
Published: June 2014

Abstract. A transient technique for generating ice sheet preindustrial initial conditions for long-term coupled ice sheet/climate model simulations is developed and demonstrated over the Greenland ice sheet using the Community Earth System Model (CESM). End-member paleoclimate simulations of the last glacial maximum, mid-Holocene optimum and the preindustrial are combined using weighting provided by ice core data time series to derive continuous energy-balance-model-derived surface mass balance and surface temperature fields, which are subsequently used to force a long transient ice sheet model simulation of the last glacial cycle, ending at the preindustrial. The procedure accounts for the evolution of climate through the last glacial period and converges to a simulated preindustrial ice sheet that is geometrically and thermodynamically consistent with the preindustrial CESM state, yet contains a transient memory of past climate. The preindustrial state generated using this technique notably improves upon the standard equilibrium spin-up technique, relative to observations and other model studies, although in the demonstration we present here, large biases remain due primarily to climate model forcing biases. Ultimately, the method we describe provides a clear template for generating initial conditions for ice sheets within a fully coupled climate model framework that allows for the effects of past climate history to be self-consistently included in long-term simulations of the fully coupled ice sheet/climate system.
The impact of uncertain precipitation data on insurance loss estimates using a flood catastrophe model
Authors: Sampson C. C. , Fewtrell T. J. , O'Loughlin F. , Pappenberger F. , Bates P. B. , Freer J. E. , Cloke H. L.
Published: June 2014

Abstract. Catastrophe risk models used by the insurance industry are likely subject to significant uncertainty, but due to their proprietary nature and strict licensing conditions they are not available for experimentation. In addition, even if such experiments were conducted, these would not be repeatable by other researchers because commercial confidentiality issues prevent the details of proprietary catastrophe model structures from being described in public domain documents. However, such experimentation is urgently required to improve decision making in both insurance and reinsurance markets. In this paper we therefore construct our own catastrophe risk model for flooding in Dublin, Ireland, in order to assess the impact of typical precipitation data uncertainty on loss predictions. As we consider only a city region rather than a whole territory and have access to detailed data and computing resources typically unavailable to industry modellers, our model is significantly more detailed than most commercial products. The model consists of four components, a stochastic rainfall module, a hydrological and hydraulic flood hazard module, a vulnerability module, and a financial loss module. Using these we undertake a series of simulations to test the impact of driving the stochastic event generator with four different rainfall data sets: ground gauge data, gauge-corrected rainfall radar, meteorological reanalysis data (European Centre for Medium-Range Weather Forecasts Reanalysis-Interim; ERA-Interim) and a satellite rainfall product (The Climate Prediction Center morphing method; CMORPH). Catastrophe models are unusual because they use the upper three components of the modelling chain to generate a large synthetic database of unobserved and severe loss-driving events for which estimated losses are calculated. We find the loss estimates to be more sensitive to uncertainties propagated from the driving precipitation data sets than to other uncertainties in the hazard and vulnerability modules, suggesting that the range of uncertainty within catastrophe model structures may be greater than commonly believed.
Time scales of regional circulation of saline fluids in continental aquifers (Armorican massif, Western France)
Authors: Armandine Les Landes A. , Aquilina L. , Davy P. , Vergnaud V. , le Carlier C.
Published: June 2014

Abstract. In recent decades, saline fluids have been sampled worldwide at great depths in continental basements. Although some of them have been attributed to marine transgressions the mechanisms allowing their circulation is not understood. In this paper, we describe the horizontal and vertical distribution of moderately saline fluids (60 to 1400 mg L−1) sampled at depths ranging from 41 to 200 m in aquifers at the regional scale of the Armorican Massif (northwestern France). The horizontal and vertical distributions of high chloride concentrations are in good agreement with both the altitudinal and vertical limits and succession of the three major transgressions between the Mio-Pliocene and Pleistocene ages. The mean chloride concentration for each transgression area is exponentially related to the time spanned until present. It defines the potential laws of leaching of marine waters by fresh meteoric waters. The results of the Armorican aquifers provide the first observed constraints for the time scales of seawater circulation in the continental basement and the subsequent leaching by fresh meteoric waters. The general trend of increasing chloride concentration with depth and the time frame for the flushing process provide useful information to develop conceptual models of the paleo-functionning of Armorican aquifers.
Iron oxidation kinetics and phosphate immobilization along the flow-path from groundwater into surface water
Authors: van der Grift B. , Rozemeijer J. C. , Griffioen J. , van der Velde Y.
Published: June 2014

Abstract. The retention of phosphorus in surface waters though co-precipitation of phosphate with Fe-oxyhydroxides during exfiltration of anaerobic Fe(II) rich groundwater is not well understood. We developed an experimental field set-up to study Fe(II) oxidation and P immobilization along the flow-path from groundwater to surface water in an agricultural experimental catchment of a small lowland river. We physically separated tube drain effluent from groundwater discharge before it entered a ditch in an agricultural field. Through continuous discharge measurements and weekly water quality sampling of groundwater, tube drain water, exfiltrated groundwater, and ditch water, we investigated Fe(II) oxidation kinetics and P immobilization processes. The oxidation rate inferred from our field measurements closely agreed with the general rate law for abiotic oxidation of Fe(II) by O2. Seasonal changes in climatic conditions affected the Fe(II) oxidation process. Lower pH and lower temperatures in winter (compared to summer) resulted in low Fe oxidation rates. After exfiltration to the surface water, it took a couple of days to more than one week before complete oxidation of Fe(II) is reached. In summer time, Fe oxidation rates were much higher. The Fe concentrations in the exfiltrated groundwater were low, indicating that dissolved Fe(II) is completely oxidized prior to inflow into a ditch. While the Fe oxidation rates reduce drastically from summer to winter, P concentrations remained high in the groundwater and an order of magnitude lower in the surface water throughout the year. This study shows very fast immobilisation of dissolved P during the initial stage of the Fe(II) oxidation proces which results in P-depleted water before Fe(II) is competly depleted. This cannot be explained by surface complexation of phosphate to freshly formed Fe-oxyhydroxides but indicates the formation of Fe(III)-phosphate precipitates. The formation of Fe(III)-phosphates at redox gradients seems an important geochemical mechanism in the transformation of dissolved phosphate to particulate phosphate and, therefore, a major control on the P retention in natural waters that drain anaerobic aquifers.
An assessment of landslide susceptibility in the Faifa area, Saudi Arabia, using remote sensing and GIS techniques
Authors: Alharbi T. , Sultan M. , Sefry S. , ElKadiri R. , Ahmed M. , Chase R. , Milewski A. , Abu Abdullah M. , Emil M. , Chounaird K.
Published: June 2014

Abstract. An integrated approach was adopted over Faifa Mountain and its surroundings, in Saudi Arabia, to identify landslide types, distribution, and controlling factors, and to generate landslide susceptibility maps. Given the inaccessibility of the area, we relied on remote sensing observations and GIS-based applications to enable spatial analysis of data and extrapolation of limited field observations. Susceptibility maps depicting debris flows within ephemeral valleys (Type I) and landslides caused by failure along fracture planes (Type II) were generated. Type I susceptibility maps were generated applying linear relationships between normalized difference vegetation index (NDVI) and threshold slope values (30°), both of which were extracted over known debris flow locations. For Type II susceptibility maps, landslides were predicted if fracture planes had strike values similar to (within 20°) those of the slope face strike and dip angles exceeding the friction, but not the slope angles. Comparisons between predicted and observed debris flows yielded success rates of 82% (ephemeral valleys); unverified predictions are interpreted as future locations of debris flows. Our approach could serve as a replicable model for many areas worldwide, in areas where field measurements are difficult to obtain and/or are cost prohibitive.
Assessment of the structure and variability of Weddell Sea water masses in distinct ocean reanalysis products
Authors: Dotto T. S. , Kerr R. , Mata M. M. , Azaneu M. , Wainer I. , Fahrbach E. , Rohardt G.
Published: June 2014

Abstract. We assessed and evaluated the performance of five ocean reanalysis products in reproducing essential hydrographic properties and their associated temporal variability for the Weddell Sea, Antarctica. The products used in this assessment were ECMWF ORAS4 (European Centre for Medium-Range Weather Forecasts Ocean Reanalysis System 4), CFSR (Climate Forecast System Reanalysis), MyOcean UR025.4 (University of Reading), ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II) and SODA (Simple Ocean Data Assimilation). The present study focuses on the Weddell Sea deep layer, which is composed of the following three main water masses: Warm Deep Water (WDW), Weddell Sea Deep Water (WSDW) and Weddell Sea Bottom Water (WSBW). The MyOcean UR025.4 product provided the most accurate representation of the structure and thermohaline properties of the Weddell Sea water masses when compared with observations. All the ocean reanalysis products analyzed exhibited limited capabilities in representing the surface water masses in the Weddell Sea. The CFSR and ECCO2 products were not able to represent deep water masses with a neutral density ≥ 28.40 kg m−3, which was considered the WSBW's upper limit throughout the simulation period. The expected WDW warming was only reproduced by the SODA product, whereas the ECCO2 product was able to represent the trends in the WSDW's hydrographic properties. All the assessed ocean reanalyses were able to represent the decrease in the WSBW's density, except the SODA product in the inner Weddell Sea. Improvements in parameterization may have as much impact on the reanalyses assessed as improvements in horizontal resolution primarily because the Southern Ocean lacks in situ data, and the data that are currently available are summer-biased. The choice of the reanalysis product should be made carefully, taking into account the performance, the parameters of interest, and the type of physical processes to be evaluated.
Evaluation of wet troposphere path delays from atmospheric reanalyses and radiometers and their impact on the altimeter sea level
Authors: Legeais J.-F. , Ablain M. , Thao S.
Published: June 2014

Abstract. The assessment of long-term errors in altimeter sea level measurements is essential for studies related to the mean sea level (MSL) evolution. One of the main contributors to the long-term sea level uncertainties is the correction of the altimeter range from the wet troposphere path delay, which is provided by onboard microwave radiometers for the main altimeter missions. The wet troposphere correction (WTC) derived from the operational European Centre for Medium-Range Weather Forecast (ECMWF) atmospheric model is usually used as a reference for comparison with the radiometer WTC. However, due to several improvements of the processing, this model is not homogenous over the altimetry period (from 1993 onwards), preventing the detection of errors in the radiometer WTC, especially in the first altimetry decade. In this study, we determine the quality of WTC provided by the operational ECMWF atmospheric model in comparison with the fields derived from the ERA Interim (ECMWF) and the National Centers for Environmental Predictions/National Center for Atmospheric Research (NCEP/NCAR) reanalyses. Separating our analyses on several temporal and spatial scales, we demonstrate that ERA Interim provides the best modeled WTC for the altimeter sea level at climate scales. This allows us to better evaluate the radiometer WTC errors, especially for the first altimetry decade (1993–2002), and thus to improve the altimeter MSL error budget. This work also demonstrates the relevance of the feed-backs that the "altimetry" and "atmosphere" communities can bring to each other.