bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decay of a cut‐off low and contribution to stratosphere‐troposphere exchange
Authors: Gouget H. , Vaughan G. , Marenco A. , Smit H. G. J. 
Published: July 2010

AbstractWe present a case study of the decay of a cut‐off low over north‐west Europe in June 1996, to establish how the stratospheric air initially contained within it was transferred to the troposphere. Two mechanisms for stratosphere‐troposphere exchange are examined: direct convective erosion of the base of the low, and filamentation of the outer layers of the low along the flank of the polar jet stream. The approach taken relies on a combination of in‐situ ozone and humidity measurements by MOZAIC (Measurement of Ozone and water vapour by Airbus In‐service aircraft) aircraft and ozonesondes, and the European Centre for Medium‐Range Weather Forecasts analyses. MOZAIC ozone is used to choose two analyses eight days apart at the genesis (14 June 1996) and decay (22 June 1996) of the low which have a consistent ozone/potential‐vorticity relationship. Trajectories (both isentropic and three dimensional (3D)) between these two analyses reveal a consistent pattern; at the base of the low (310 K, 450 mb) all the trajectories attain tropospheric PV values whereas, at 320 K, those trajectories that leave the low experience a decrease in PV and those that do not leave the low retain their initial PV. We propose that air parcels leaving the low were stretched into thin filaments along the flank of the jet stream, which made them vulnerable to 3D mixing. A MOZAIC flight on 21 June 1996 provides direct evidence for this process.Up to 22 June 1996 (by which time the low had lost its closed circulation) the satellite images showed very little convection beneath the corresponding PV anomaly. Mixing was only effective at the very base of the stratospheric air at 310 K. On 22 June the remaining remnant of high PV was advected into a region of deep convection over central and eastern Europe, mixing the remaining stratospheric air into the troposphere. Of the initial mass of 1015 kg of stratospheric air contained in the low, 6 × 1014 kg was stripped into filaments along the jet and 4 × 1014 kg remained to be mixed by convection during the period 22–23 June 1996.
The ECMWF operational implementation of four‐dimensional variational assimilation. I: Experimental results with simplified physics
Authors: Rabier F. , Järvinen H. , Klinker E. , Mahfouf J.‐F. , Simmons A. 
Published: July 2010

AbstractThis paper presents results of a comparison between four‐dimensional variational assimilation (4D‐Var). using a 6‐hour assimilation window and simplified physics during the minimization, and three‐dimensional variational assimilation (3D‐Var). Results have been obtained at ‘operational’ resolution T213L31/T63L31. (T defines the spectral triangular truncation and L the number of levels in the vertical, with the first parameters defining the resolution of the model trajectory, and the second the resolution of the inner‐loop.) The sensitivity of the 4D‐Var performance to different set‐ups is investigated. In particular, the performance of 4D‐Var in the Tropics revealed some sensitivity to the way the adiabatic nonlinear normal‐mode initialization of the increments was performed. Going from four outer‐loops to only one (as in 3D‐Var), together with a change to the 1997 formulation of the background constraint and an initialization of only the small scales, helped to improve the 4D‐Var performance. Tropical scores then became only marginally worse for 4D‐Var than for 3D‐Var. Twelve weeks of experimentation with the one outer‐loop 4D‐Var and the 1997 background formulation have been studied. The averaged scores show a small but consistent improvement in both hemispheres at all ranges. In the short range, each two‐ to three‐week period has been found to be slightly positive throughout the troposphere. The better short‐range performance of the 4D‐Var system is also shown by the fits of the background fields to the data. More results are presented for the Atlantic Ocean area during FASTEX (the Fronts and Atlantic Storm‐Track Experiment), during which 4D‐Var is found to perform better. In individual synoptic cases corresponding to interesting Intensive Observing Periods, 4D‐Var has a clear advantage over 3D‐Var during rapid cyclogeneses. The very short‐range forecasts used as backgrounds are much closer to the data over the Atlantic for 4D‐Var than for 3D‐Var. The 4D‐Var analyses also display more day‐to‐day variability. Some structure functions are illustrated in the 4D‐Var case for a height observation inserted at the beginning, in the middle or at the end of the assimilation window. The dynamical processes seem to be relevant, even with a short 6‐hour assimilation period, which explains the better overall performance of the 4D‐Var system.
The ecmwf operational implementation of four‐dimensional variational assimilation. III: Experimental results and diagnostics with operational configuration
Authors: Klinker E. , Rabier F. , Kelly G. , Mahfouf J.‐F. 
Published: July 2010

AbstractThe first two papers of this series describe the development of the operational four‐dimensional variational assimilation (4D‐Var) configuration implemented at the European Centre for Medium‐Range Weather Forecasts (ECMWF). The basic features are a 6‐hour incremental 4D‐Var set‐up with two minimization steps, using very simplified physics in the first minimization and a more complete set of linear physics in the second. This paper describes the validation of this configuration. Prior to implementation, 12 weeks of experimentation showed a consistent improvement relative to 3D‐Var. After an additional 6 weeks of encouraging parallel operation with the then current operational suite, 4D‐Var with physics was introduced in operations at ECMWF in November 1997. The difference in scores is statistically significant, and the fast‐growing components of the 4D‐Var analysis errors are shown to be smaller than their 3D‐Var counterparts. The performance of this new operational assimilation system is studied for the month of January 1998, for which the 4D‐Var analyses exhibit more realistic baroclinic waves than the 3D‐Var, especially in the Pacific area. A case‐study illustrates the improvement one can expect in forecast terms in the mid latitudes. The 4D‐Var system improved the forecast skill in the Tropics in general. Observing‐system experiments show that the current 4D‐Var operational system benefits from the assimilation both of satellite data and conventional observations.
Biosphere‐atmosphere interactions over West Africa. I: Development and validation of a coupled dynamic model
Authors: Wang Guiling , Eltahjr Elfatm A. B. 
Published: July 2010

AbstractIn this study we develop a zonally symmetric, synchronously coupled biosphere‐atmosphere model including ecosystem dynamics, and apply this model to study biosphere‐atmosphere interactions in the region of West Africa. The atmospheric model is zonally symmetric, and includes representation of atmospheric dynamics, a radiation scheme, a moist convection scheme, a boundary‐layer scheme, and a cloud‐parametrization scheme. The biospheric model is the Integrated BIosphere Simulator (IBIS), which includes representation of the water, energy, momentum, and carbon balance, vegetation phenology, and vegetation dynamics. We modified the representation of canopy hydrology in IBIS to account for the impact of rainfall subgrid variability. The biospheric model and atmospheric model are separately tested against observations. The synchronously coupled model is then used to simulate the biosphere‐atmosphere system of West Africa. A study on the role of biosphere‐atmosphere interactions, including ecosystem dynamics, in the climate variability over West Africa using this model will be presented in a companion paper.
An error analysis of radiance and suboptimal retrieval assimilation
Authors: Joiner J. , Dee D. P. 
Published: July 2010

AbstractOne of the outstanding problems in data assimilation has been, and continues to be, how best to utilize satellite data while balancing the trade‐off between accuracy and computational cost. A number of weather‐prediction centres have recently achieved remarkable success in improving their forecast skill by changing the method in which satellite data are assimilated into the forecast model from the traditional approach of assimilating retrieved products to the direct assimilation of radiances in a variational framework. Although there are. clear theoretical advantages to the direct radiance‐assimilation approach, it is not obvious at all to what extent the improvements that have been obtained so far can be attributed to the change in methodology or to various technical aspects of the implementation.The central question we address here is: how much improvement can we expect from assimilating radiances rather than retrievals, all other things being equal? We compare the two approaches in a simplified theoretical framework. Direct radiance analysis is optimal in this idealized context, while the traditional method of assimilating retrievals is suboptimal because it ignores the cross‐covariances between background errors and retrieval errors. We show that interactive retrieval analysis (where the same background used for assimilation is also used in the retrieval step) is equivalent to direct assimilation of radiances with suboptimal analysis weights.We illustrate and extend these theoretical arguments with several one‐dimensional analysis experiments, where we estimate vertical atmospheric profiles using simulated data from temperature sounding channels of both the High‐resolution InfraRed Sounder 2 (HIRS2) and the future Atmospheric InfraRed Sounder (AIRS). In the case of non‐interactive retrievals the results depend very much on the quality of the background information used for the retrieval step. In all cases, the impact of the choice of analysis method is dwarfed by the effect of changing some of the experimental parameters that control the simulated error characteristics of the data and the retrieval background.
The great fireball of 1934, October 11, and an instance of streak‐drift
Authors: King A. , Whipple F. J. W. 
Published: July 2010

AbstractThe fireball, probably brighter than the full moon, first appeared over E. Yorkshire at a height of 94 miles and ended, after a flight of 58 miles, over N. Lincolnshire at a height of 51 miles. The speed mas 21 miles per sec. and the radiant at ∞, 252°‐3, 8, +750°8. The parabolic orbit deduced from the corrected radiant gave rise to the suspicion that the object may have been connected with Comet Giacobini‐Zinner.A streak was left along the track between the heights of 77 miles and 56 miles. The upper portion quickly vanished, and the part from 69 miles high to the and (56 miles high) drifted in B generally N.E. direction with rates as under for the respective heights :‐Height. Speed of drift.mls. mls. per hr.69… … … 13060 1/3 … … … 16256 … … … 150
The lunar atmospheric tide in the Azores, 1894‐1932
Authors: Chapman S. 
Published: July 2010

AbstractThe lunar atmospheric tide is determined at two stations in the Azores, namely, Ponta Delgada (38° N., 26° W.) and Santa Cruz (39° N., 31° W.), from 39 to 26 years' bi‐hourly data (all days) for the barometric pressure. The mean results are respectively 22 sin (2t + 55 °) and 18 sin (2t + 58°) in microbars, so that high tide occurs 72 and 65 (solar) minutes after lunar transit. As at most other stations, the tide is distinctly later near the December solstice than at other times. The probable errors of these mean results are 1.6 and 2.2 microbars.The harmonic coefficients for the first four components of the solar diurnal variation are also given.
The climate of the northern pennines: The coldest part of England
Authors: Manley Gordon 
Published: July 2010

AbstractThe northern Pennine moorlands comprise the most consistently elevated and chilly part of England. Very few observations are available however as regard temperature, although an interesting record, showing great extremes, was maintained near Alston from 18b1886. Rainfall is better known; other climatic features of especial note include occasional peculiarly violent thunderstorms and the well‐known “helm wind.” The writer has established a station at which temperatures have been taken in a standard screen since early in 1932; this is at a keeper's cottage on the exposed moorland of Upper Teesdale just to the south‐east of Crossfell. The altitude (1,840 ft.) makes the station the highest at which a continuous record has been kept in England. In general, although mean temperatures differ by about 5°.5F., no more than might be expected, from a group of Northern lon.land stations, the maxima are decidedly lower (7°. o) while the minima are not so much lower (3°. 3); and the mean daily range of temperature on the uplands is less than that in the valleys. This is to be expected; but exceptional extremes occur on particular occasions which appear to be due to the position of the moorland basin in which the station lies. As a whole the figures confirm the prevailing impression of bleakness associated with a windy and damp upland and correspond well with rccords at sea level in Southern Iceland.
Formation of nitrogenated organic aerosols in the Titan upper atmosphere
Authors: Imanaka Hiroshi , Smith Mark A. 
Published: July 2010

Many aspects of the nitrogen fixation process by photochemistry in the Titan atmosphere are not fully understood. The recent Cassini mission revealed organic aerosol formation in the upper atmosphere of Titan. It is not clear, however, how much and by what mechanism nitrogen is incorporated in Titan’s organic aerosols. Using tunable synchrotron radiation at the Advanced Light Source, we demonstrate the first evidence of nitrogenated organic aerosol production by extreme ultraviolet–vacuum ultraviolet irradiation of a N
2
/CH
4
gas mixture. The ultrahigh-mass-resolution study with laser desorption ionization-Fourier transform-ion cyclotron resonance mass spectrometry of N
2
/CH
4
photolytic solid products at 60 and 82.5 nm indicates the predominance of highly nitrogenated compounds. The distinct nitrogen incorporations at the elemental abundances of H
2
C
2
N and HCN, respectively, are suggestive of important roles of H
2
C
2
N/HCCN and HCN/CN in their formation. The efficient formation of unsaturated hydrocarbons is observed in the gas phase without abundant nitrogenated neutrals at 60 nm, and this is confirmed by separately using
13
C and
15
N isotopically labeled initial gas mixtures. These observations strongly suggest a heterogeneous incorporation mechanism via short lived nitrogenated reactive species, such as HCCN radical, for nitrogenated organic aerosol formation, and imply that substantial amounts of nitrogen is fixed as organic macromolecular aerosols in Titan’s atmosphere.
Finite-temperature critical point of a glass transition
Authors: Elmatad Yael S. , Jack Robert L. , Chandler David , Garrahan Juan P. 
Published: July 2010

We generalize the simplest kinetically constrained model of a glass-forming liquid by softening kinetic constraints, allowing them to be violated with a small rate. We demonstrate that this model supports a first-order dynamical (space–time) phase transition between active (fluid) and inactive (glass) phases. The first-order phase boundary in this softened model ends in a finite-temperature dynamical critical point, which may be present in natural systems. In this case, the glass phase has a very large but finite relaxation time. We discuss links between the dynamical critical point and quantum phase transitions, showing that dynamical phase transitions in
d
dimensions map to quantum transitions in the same dimension, and hence to classical thermodynamic phase transitions in
d
+ 1 dimensions.
The effectiveness of workplace counselling: A systematic review
Authors: McLeod John 
Published: July 2010

AbstractBackground: In response to the stresses of the contemporary workplace, the challenges of maintaining satisfactory work‐life balance, and the costs to business of employee mental health problems, many organisations have contracted to make counselling services available to their staff. It is essential to evaluate the effectiveness of workplace counselling, in order to maintain standards, and to identify examples of good practice. Objectives: This paper presents a comprehensive, systematic review of the effectiveness of workplace counselling. Findings are analysed in terms of client satisfaction, psychological functioning, the meaning of work, work behaviour, and negative outcomes. Findings: Taken as a whole, the results of research suggest that counselling is generally effective in alleviating psychological problems, has a significant impact on sickness absence, and has a moderate effect on attitudes to work. Discussion: Methodological issues are discussed, and it is recommended that more high‐quality research is required in order to reinforce the evidence base for workplace counselling in relation to a number of key questions.
What difference does counselling make? – The perceptions of drug‐using clients on low incomes
Authors: Edwards Jane , Loeb Sarah 
Published: July 2010

AbstractContext: This paper reports on a qualitative study looking at the perceptions of clients who use drugs and are on low income. Research suggests that counselling services can experience difficulties in reaching and retaining such clients, and outcomes of counselling can be disappointing. Aim: To learn from clients who had engaged in counselling for over six months what difference it had made to their lives. Method: Grounded theory methodology was used to analyse semi‐structured interviews with six participants. Findings: Findings included changes in the clients’ internal world, their connectedness with society, their familiarity with counselling, and their perception of the relationship with the counsellor. Factors within the counselling process which helped and hindered change were identified. The study documents how participants were able to use counselling to improve their lives.
In defense of the reference: more than linking in evolving Web environments
Authors: ANDERSON‐WILK Mark 
Published: July 2010

ABSTRACTEven in today's intensively hyperlinked environment, full bibliographic citations continue to serve the important functions of attribution, accountability, and conversation that are at the heart of scholarly publishing. However, the long‐running tradition of citation documentation is being increasingly eroded and challenged by new Web technologies and practices. This paper discusses the implications of scholarly publishing reference practices in the rapidly evolving medium of the Web. A model for greater separation of author‐documented citations and user‐centric linking is proposed.
Effect of hatching date, vertical distribution, and interannual variation in physical forcing on northward displacement and temperature conditions of Norwegian spring-spawning herring larvae
Authors: Vikebø Frode B. , Husebø Åse , Slotte Aril , Stenevik Erling Kåre , Lien Vidar S. 
Published: July 2010

Abstract
Vikebø, F. B., Husebø, Å., Slotte, A., Stenevik, E. K., and Lien, V. S. 2010. Effect of hatching date, vertical distribution, and interannual variation in physical forcing on northward displacement and temperature conditions of Norwegian spring-spawning herring larvae. – ICES Journal of Marine Science, 67: 1948–1956. Early hatching has been shown to be associated with increased survival of Norwegian spring-spawning herring (Clupea harengus) larvae. We investigated whether the process behind this association is related to larval drift and ambient temperature. A three-dimensional hydrodynamic model was used to simulate the effect of hatching date on northward displacement and temperature conditions of larvae from spawning grounds off western Norway for 1989–2008. The simulations revealed that the displacement during a period of 60 d was greatest if the larvae hatched early in the season and if they were located near the surface. The relationship between drift speed and ambient temperature was significantly negative, but less so later in the season, because the coastal current became progressively warmer. Results from the simulated interannual variations in larval drift compared with the observed survival suggest that a rapid northward displacement to the main nursery area in the Barents Sea is more important for larval survival than ambient temperature. The significant effect of northward displacement on survival could be explained by reduced overlap with predators and/or higher prey densities, but the causal processes involved remain to be investigated.
Spanish otter trawl fisheries in the Cantabrian Sea
Authors: Punzón Antonio , Hernández Carmen , Abad Esther , Castro José , Pérez Nelida , Trujillo Valentín 
Published: July 2010

Abstract
Punzón, A., Hernández, C., Abad, E., Castro, J., Pérez, N., and Trujillo, V. 2010. Spanish otter trawl fisheries in the Cantabrian Sea. – ICES Journal of Marine Science 67: 1604–1616 A non-hierarchical classification technique (clustering large applications, CLARA) was used to identify four fishing tactics of Spanish otter trawlers in the Cantabrian Sea (ICES Division VIIIc) from 1983 to 2004: mixed fishing, blue whiting fishing, horse mackerel fishing, and mackerel fishing. There were no significant differences in the fishing tactics employed by two trawl fleets identified using a non-hierarchical classification technique (partition around medoids). There was, however, a decline in the use of the blue whiting fishing tactic from 2000 on, perhaps as a result of competition with pairtrawls, a gear whose main target species is blue whiting. There was an increase in the number of trips using the mackerel fishing tactic from 1996, a change possibly caused by improved market conditions. Between 2000 and 2004, the fleets had two distinct behaviour patterns, identified depending on the area in which they operated. The study area could therefore be subdivided into two areas based on the prevalence of the fishing tactic followed. The horse mackerel fishing tactic was more commonly used in the west, and the mixed fishing tactic in the east.