101 resultados para Android maps mappe gcm push notification push-notification sensors sensori


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This study examines the effect of seasonally varying chlorophyll on the climate of the Arabian Sea and South Asian monsoon. The effect of such seasonality on the radiative properties of the upper ocean is often a missing process in coupled general circulation models and its large amplitude in the region makes it a pertinent choice for study to determine any impact on systematic biases in the mean and seasonality of the Arabian Sea. In this study we examine the effects of incorporating a seasonal cycle in chlorophyll due to phytoplankton blooms in the UK Met Office coupled atmosphere-ocean GCM HadCM3. This is achieved by performing experiments in which the optical properties of water in the Arabian Sea - a key signal of the semi-annual cycle of phytoplankton blooms in the region - are calculated from a chlorophyll climatology derived from Sea-viewing Wide Field-of-View Sensor (SeaWiFS) data. The SeaWiFS chlorophyll is prescribed in annual mean and seasonally-varying experiments. In response to the chlorophyll bloom in late spring, biases in mixed layer depth are reduced by up to 50% and the surface is warmed, leading to increases in monsoon rainfall during the onset period. However when the monsoons are fully established in boreal winter and summer and there are strong surface winds and a deep mixed layer, biases in the mixed layer depth are reduced but the surface undergoes cooling. The seasonality of the response of SST to chlorophyll is found to depend on the relative depth of the mixed layer to that of the anomalous penetration depth of solar fluxes. Thus the inclusion of the effects of chlorophyll on radiative properties of the upper ocean acts to reduce biases in mixed layer depth and increase seasonality in SST.

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A semiochemical based push-pull strategy for control of oilseed rape pests is being developed at Rothamsted Research. This strategy uses insect and plant derived semiochemicals to manipulate pests and their natural enemies. An important element within this strategy is an understanding of the importance of non-host plant cues for pest insects and how such signals could be used to manipulate their behaviour. Previous studies using a range of non-host plants have shown that, for the pollen beetle Meligethes aeneus (Coleoptera: Nitidulidae), the essential oil of lavender, Lavandula angustifolia (Lamiaceae), was the most repellent. The aim of this study was to identify the active components in L. angustifolia oil, and to investigate the behaviour of M. aeneus to these chemicals, to establish the most effective use of repellent stimuli to disrupt colonisation of oilseed rape crops. Coupled gas chromatography-electroantennography (GC-EAG) and gas chromatography-mass spectrometry (GC-MS) resulted in the identification of seven active compounds which were tested for behavioural activity using a 4-way olfactometer. Repellent responses were observed with (±)-linalool and (±)-linalyl acetate. The use of these chemicals within a push-pull pest control strategy is discussed.

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We develop a model to illustrate potential complexities in the relationship between corporate geographical diversification and the health and safety (H&S) standards set in national jurisdictions. A firm, that initially has a plant in its home country, may choose to also have one or two foreign plants in order to improve its bargaining position versus local governments, and so ensure reduced H&S standards, i.e. a race-to-the-bottom. However, contrary to the main focus of the popular debate on this topic, we note the potential for the race-to-the-bottom tendency to be exerted on H&S standards in the multinational company’s home rather than host country, and also for an upward push on H&S to instead result.

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The themes of awareness and influence within the innovation diffusion process are addressed. The innovation diffusion process is typically represented as stages, yet awareness and influence are somewhat under-represented in the literature. Awareness and influence are situated within the contextual setting of individual actors but also within the broader institutional forces. Understanding how actors become aware of an innovation and then how their opinion is influenced is important for creating a more innovation-active UK construction sector. Social network analysis is proposed as one technique for mapping how awareness and influence occur and what they look like as a network. Empirical data are gathered using two modes of enquiry. This is done through a pilot study consisting of chartered professionals and then through a case study organization as it attempted to diffuse an innovation. The analysis demonstrates significant variations across actors’ awareness and influence networks. It is argued that social network analysis can complement other research methods in order to present a richer picture of how actors become aware of innovations and where they draw their influences regarding adopting innovations. In summarizing the findings, a framework for understanding awareness and influence associated with innovation within the UK construction sector is presented. Finally, with the UK construction sector continually being encouraged to be innovative, understanding and managing an actor’s awareness and influence network will be beneficial. The overarching conclusion thus describes the need not only to build research capacity in this area but also to push the boundaries related to the research methods employed.

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A new parameterisation is described that predicts the temperature perturbations due to sub-grid scale orographic gravity waves in the atmosphere of the 19 level HadAM3 version of the United Kingdom Met Office Unified Model. The explicit calculation of the wave phase allows the sign of the temperature perturbation to be predicted. The scheme is used to create orographic clouds, including cirrus, that were previously absent in model simulations. A novel approach to the validation of this parameterisation makes use of both satellite observations of a case study, and a simulation in which the Unified Model is nudged towards ERA-40 assimilated winds, temperatures and humidities. It is demonstrated that this approach offers a feasible way of introducing large scale orographic cirrus clouds into GCMs.

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This spreadsheet contains key data about that part of the endgame of Western Chess for which Endgame Tables (EGTs) have been generated by computer. It is derived from the EGT work since 1969 of Thomas Ströhlein, Ken Thompson, Christopher Wirth, Eugene Nalimov, Marc Bourzutschky, John Tamplin and Yakov Konoval. The data includes %s of wins, draws and losses (wtm and btm), the maximum and average depths of win under various metrics (DTC = Depth to Conversion, DTM = Depth to Mate, DTZ = Depth to Conversion or Pawn-push), and examples of positions of maximum depth. It is essentially about sub-7-man Chess but is updated as news comes in of 7-man EGT computations.

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A precipitation downscaling method is presented using precipitation from a general circulation model (GCM) as predictor. The method extends a previous method from monthly to daily temporal resolution. The simplest form of the method corrects for biases in wet-day frequency and intensity. A more sophisticated variant also takes account of flow-dependent biases in the GCM. The method is flexible and simple to implement. It is proposed here as a correction of GCM output for applications where sophisticated methods are not available, or as a benchmark for the evaluation of other downscaling methods. Applied to output from reanalyses (ECMWF, NCEP) in the region of the European Alps, the method is capable of reducing large biases in the precipitation frequency distribution, even for high quantiles. The two variants exhibit similar performances, but the ideal choice of method can depend on the GCM/reanalysis and it is recommended to test the methods in each case. Limitations of the method are found in small areas with unresolved topographic detail that influence higher-order statistics (e.g. high quantiles). When used as benchmark for three regional climate models (RCMs), the corrected reanalysis and the RCMs perform similarly in many regions, but the added value of the latter is evident for high quantiles in some small regions.

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Northern Hemisphere tropical cyclone (TC) activity is investigated in multiyear global climate simulations with theECMWFIntegrated Forecast System (IFS) at 10-km resolution forced by the observed records of sea surface temperature and sea ice. The results are compared to analogous simulationswith the 16-, 39-, and 125-km versions of the model as well as observations. In the North Atlantic, mean TC frequency in the 10-km model is comparable to the observed frequency, whereas it is too low in the other versions. While spatial distributions of the genesis and track densities improve systematically with increasing resolution, the 10-km model displays qualitatively more realistic simulation of the track density in the western subtropical North Atlantic. In the North Pacific, the TC count tends to be too high in thewest and too low in the east for all resolutions. These model errors appear to be associated with the errors in the large-scale environmental conditions that are fairly similar in this region for all model versions. The largest benefits of the 10-km simulation are the dramatically more accurate representation of the TC intensity distribution and the structure of the most intense storms. The model can generate a supertyphoon with a maximum surface wind speed of 68.4 m s21. The life cycle of an intense TC comprises intensity fluctuations that occur in apparent connection with the variations of the eyewall/rainband structure. These findings suggest that a hydrostatic model with cumulus parameterization and of high enough resolution could be efficiently used to simulate the TC intensity response (and the associated structural changes) to future climate change.

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Accurate decadal climate predictions could be used to inform adaptation actions to a changing climate. The skill of such predictions from initialised dynamical global climate models (GCMs) may be assessed by comparing with predictions from statistical models which are based solely on historical observations. This paper presents two benchmark statistical models for predicting both the radiatively forced trend and internal variability of annual mean sea surface temperatures (SSTs) on a decadal timescale based on the gridded observation data set HadISST. For both statistical models, the trend related to radiative forcing is modelled using a linear regression of SST time series at each grid box on the time series of equivalent global mean atmospheric CO2 concentration. The residual internal variability is then modelled by (1) a first-order autoregressive model (AR1) and (2) a constructed analogue model (CA). From the verification of 46 retrospective forecasts with start years from 1960 to 2005, the correlation coefficient for anomaly forecasts using trend with AR1 is greater than 0.7 over parts of extra-tropical North Atlantic, the Indian Ocean and western Pacific. This is primarily related to the prediction of the forced trend. More importantly, both CA and AR1 give skillful predictions of the internal variability of SSTs in the subpolar gyre region over the far North Atlantic for lead time of 2 to 5 years, with correlation coefficients greater than 0.5. For the subpolar gyre and parts of the South Atlantic, CA is superior to AR1 for lead time of 6 to 9 years. These statistical forecasts are also compared with ensemble mean retrospective forecasts by DePreSys, an initialised GCM. DePreSys is found to outperform the statistical models over large parts of North Atlantic for lead times of 2 to 5 years and 6 to 9 years, however trend with AR1 is generally superior to DePreSys in the North Atlantic Current region, while trend with CA is superior to DePreSys in parts of South Atlantic for lead time of 6 to 9 years. These findings encourage further development of benchmark statistical decadal prediction models, and methods to combine different predictions.

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This study investigates the impacts of the transition of El Niño decaying phases on the western North Pacific anticyclone (WNPAC) anomalies in the subsequent summer with a coupled GCM. The modeling results suggest that the El Niños with short decaying phases lead to significant WNPAC anomalies in the following summer, which are contributed to mainly by the El Niños followed by La Niñas, in comparison with those not followed by La Niñas. In contrast, the long decaying cases are associated with the disappearance of WNPAC anomalies in the summer. These differences in the WNP circulation anomalies can be explained by the different configurations of simultaneous SSTs in the Indian Ocean and in the central and eastern tropical Pacific: positive SSTs in the former region and negative ones in the latter region constructively induce significant WNPAC anomalies for the short decaying cases, while the roles of positive SSTs in both regions for the long decaying cases work destructively and lead to weak WNP circulation anomalies. Further analysis indicates that the different lengths of El Niño decaying phases are predicted by the strength of Indian Ocean SSTs in the mature winter. The warmer wintertime Indian Ocean SSTs favor the anomalous easterly wind over the western and central equatorial Pacific in the subsequent summer, leading to a short decaying of El Niño. Thus, the strength of wintertime Indian Ocean SSTs is one of the important factors that affect the length of El Niño decaying phase and resultant WNPAC anomalies in the following summer.

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In this study, the authors evaluate the (El Niño–Southern Oscillation) ENSO–Asian monsoon interaction in a version of the Hadley Centre coupled ocean–atmosphere general circulation model (CGCM) known as HadCM3. The main focus is on two evolving anomalous anticyclones: one located over the south Indian Ocean (SIO) and the other over the western North Pacific (WNP). These two anomalous anticyclones are closely related to the developing and decaying phases of the ENSO and play a crucial role in linking the Asian monsoon to ENSO. It is found that the HadCM3 can well simulate the main features of the evolution of both anomalous anticyclones and the related SST dipoles, in association with the different phases of the ENSO cycle. By using the simulated results, the authors examine the relationship between the WNP/SIO anomalous anticyclones and the ENSO cycle, in particular the biennial component of the relationship. It is found that a strong El Niño event tends to be followed by a more rapid decay and is much more likely to become a La Niña event in the subsequent winter. The twin anomalous anticyclones in the western Pacific in the summer of a decaying El Niño are crucial for the transition from an El Niño into a La Niña. The El Niño (La Niña) events, especially the strong ones, strengthen significantly the correspondence between the SIO anticyclonic (cyclonic) anomaly in the preceding autumn and WNP anticyclonic (cyclonic) anomaly in the subsequent spring, and favor the persistence of the WNP anomaly from spring to summer. The present results suggest that both El Niño (La Niña) and the SIO/WNP anticyclonic (cyclonic) anomalies are closely tied with the tropospheric biennial oscillation (TBO). In addition, variability in the East Asian summer monsoon, which is dominated by the internal atmospheric variability, seems to be responsible for the appearance of the WNP anticyclonic anomaly through an upper-tropospheric meridional teleconnection pattern over the western and central Pacific.

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Global flood hazard maps can be used in the assessment of flood risk in a number of different applications, including (re)insurance and large scale flood preparedness. Such global hazard maps can be generated using large scale physically based models of rainfall-runoff and river routing, when used in conjunction with a number of post-processing methods. In this study, the European Centre for Medium Range Weather Forecasts (ECMWF) land surface model is coupled to ERA-Interim reanalysis meteorological forcing data, and resultant runoff is passed to a river routing algorithm which simulates floodplains and flood flow across the global land area. The global hazard map is based on a 30 yr (1979–2010) simulation period. A Gumbel distribution is fitted to the annual maxima flows to derive a number of flood return periods. The return periods are calculated initially for a 25×25 km grid, which is then reprojected onto a 1×1 km grid to derive maps of higher resolution and estimate flooded fractional area for the individual 25×25 km cells. Several global and regional maps of flood return periods ranging from 2 to 500 yr are presented. The results compare reasonably to a benchmark data set of global flood hazard. The developed methodology can be applied to other datasets on a global or regional scale.

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The use of semiochemicals for the manipulation of the pollen beetle, Meliethes aeneus (Fabricius) (Coleoptera: Nitidulidae), is being investigated for potential incorporation into a push-pull strategy for this pest, which damages oilseed rape, Brassica napus L. (Brassicaceae), throughout Europe. Previous laboratory behavioural studies using volatiles from non-host plants showed that M. aeneus is repelled by the odour of lavender, Lavendula angustifolia Mill. (Lamiaceae), essential oil. This article reports on semi-field and field trials to investigate this behaviour under more realistic conditions. Semi-field experiments were conducted to assess the relative importance of olfaction at different points in host location behaviour by M. aeneus. The results showed that oilseed rape plants treated with lavender odour were less colonised by M. aeneus in comparison with an untreated control, but that the treatment effect was much reduced if the lavender odour was applied after colonisation. The field experiment demonstrated that lavender odour caused a significant reduction in the number of adultM. aeneus infesting the oilseed rape plants in the treatment plots compared to the control plots. Overall, these findings are very encouraging for the future development of a push-pull pest control system.

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The chapter starts from the premise that an historically- and institutionally-formed orientation to music education at primary level in European countries privileges a nineteenth century Western European music aesthetic, with its focus on formal characteristics such as melody and rhythm. While there is a move towards a multi-faceted understanding of musical ability, a discrete intelligence and willingness to accept musical styles or 'open-earedness', there remains a paucity of documented evidence of this in research at primary school level. To date there has been no study undertaken which has the potential to provide policy makers and practitioners with insights into the degree of homogeneity or universality in conceptions of musical ability within this educational sector. Against this background, a study was set up to explore the following research questions: 1. What conceptions of musical ability do primary teachers hold a) of themselves and; b) of their pupils? 2. To what extent are these conceptions informed by Western classical practices? A mixed methods approach was used which included survey questionnaire and semi-structured interview. Questionnaires have been sent to all classroom teachers in a random sample of primary schools in the South East of England. This was followed up with a series of semi-structured interviews with a sub-sample of respondents. The main ideas are concerned with the attitudes, beliefs and working theories held by teachers in contemporary primary school settings. By mapping the extent to which a knowledge base for teaching can be resistant to change in schools, we can problematise primary schools as sites for diversity and migration of cultural ideas. Alongside this, we can use the findings from the study undertaken in an English context as a starting point for further investigation into conceptions of music, musical ability and assessment held by practitioners in a variety of primary school contexts elsewhere in Europe; our emphasis here will be on the development of shared understanding in terms of policies and practices in music education. Within this broader framework, our study can have a significant impact internationally, with potential to inform future policy making, curriculum planning and practice.