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Better Skill (good + skill)

Distribution by Scientific Domains

Earth and Environmental Science	75%

Selected Abstracts

Performance comparison of some dynamical and empirical downscaling methods for South Africa from a seasonal climate modelling perspective

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2009
Willem A. Landman
Abstract The ability of advanced state-of-the-art methods of downscaling large-scale climate predictions to regional and local scale as seasonal rainfall forecasting tools for South Africa is assessed. Various downscaling techniques and raw general circulation model (GCM) output are compared to one another over 10 December-January-February (DJF) seasons from 1991/1992 to 2000/2001 and also to a baseline prediction technique that uses only global sea-surface temperature (SST) anomalies as predictors. The various downscaling techniques described in this study include both an empirical technique called model output statistics (MOS) and a dynamical technique where a finer resolution regional climate model (RCM) is nested into the large-scale fields of a coarser GCM. The study addresses the performance of a number of simulation systems (no forecast lead-time) of varying complexity. These systems' performance is tested for both homogeneous regions and for 963 stations over South Africa, and compared with each other over the 10-year test period. For the most part, the simulations method outscores the baseline method that uses SST anomalies to simulate rainfall, therefore providing evidence that current approaches in seasonal forecasting are outscoring earlier ones. Current operational forecasting approaches involve the use of GCMs, which are considered to be the main tool whereby seasonal forecasting efforts will improve in the future. Advantages in statistically post-processing output from GCMs as well as output from RCMs are demonstrated. Evidence is provided that skill should further improve with an increased number of ensemble members. The demonstrated importance of statistical models in operation capacities is a major contribution to the science of seasonal forecasting. Although RCMs are preferable due to physical consistency, statistical models are still providing similar or even better skill and should still be applied. Copyright © 2008 Royal Meteorological Society [source]

On the use of the intensity-scale verification technique to assess operational precipitation forecasts

METEOROLOGICAL APPLICATIONS, Issue 1 2008
Gabriella Csima
Abstract The article describes the attempt to include the intensity-scale technique introduced by Casati et al. (2004) into a set of standardized verifications used in operational centres. The intensity-scale verification approach accounts for the spatial structure of the forecast field and allows the skill to be diagnosed as a function of the scale of the forecast error and intensity of the precipitation events. The intensity-scale method has been used to verify two different resolutions of the European Centre for Medium-Range Weather Forecasts (ECMWF) operational quantitative precipitation forecast (QPF) over France, and to compare the performance of the ECMWF and the Hungarian Meteorological Service operational model (ALADIN) forecasts, run over Hungary. Two case studies have been introduced, which show some interesting insight into the spatial scale of the error. The distribution of daily skill score for an extended period of time is also presented. The intensity-scale technique shows that the forecasts in general exhibit better skill for large-scale events, and lower skill for small-scale and intense events. In the paper, it is mentioned how some of the stringent assumptions on the domain over which the method can be applied, and the availability of the matched forecasts and observations, can limit its usability in an operational environment. Copyright © 2008 Royal Meteorological Society [source]

Information and communication technology among undergraduate dental students in Finland

EUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2002
Jorma I. Virtanen
Use of information and communication technology (ICT) is rapidly increasing in medical and dental education. The aim of the present study was to determine the knowledge, skills and opinions of dental undergraduate students regarding ICT and to analyze possible shifts in the acquisition of these resources. For these purposes a survey of all undergraduate dental students at the University of Oulu, Finland, was conducted during the spring term 2000. All the students in the 5 years of study (n = 140) were asked to answer a questionnaire presented during a lecture or demonstration. An overall response rate of 95% was achieved. The frequencies and percentage distributions of the items were analyzed separately for each year (1,5). All the students in the faculty are provided with personal e-mail addresses at the beginning of their studies and special emphasis has been laid on the utilization of their ICT knowledge and skills. An overwhelming majority of the students, more than 95%, judged themselves to have good or satisfactory skills in word processing, but only a slight majority considered that they could manage some advanced operating system functions. Use of ICT services was high, as about 60% of the students used e-mail and one-third WWW services daily. Literature retrieval was widely employed, so that almost 80% of the students had used literature databases (including Ovid Medline and collections of electronic full-text articles), which were introduced and provided by the Medical Library when the students were in their second year. More than 50% had received educational material in electronic form often or sometimes, and almost 80% had communicated by e-mail with a faculty teacher. A clear trend (P < 0.05) was found for the younger students to use ICT services in general and for educational purposes more often than the older ones. In conclusion, e-mail and WWW have been widely adopted for both private and educational purposes by dental students in Finland and are employed together with WWW-based medical and dental publication databases. The younger students have more interest in ICT and better skills, which presents a challenge for dental education in the future. [source]

Statistical interpretation of NWP products in India

METEOROLOGICAL APPLICATIONS, Issue 1 2002
Parvinder Maini
Although numerical weather prediction (NWP) models provide an objective forecast, poor representation of local topography and other features in these models, necessitates statistical interpretation (SI) of NWP products in terms of local weather. The Perfect Prognostic Method (PPM) is one of the techniques for accomplishing this. At the National Center for Medium Range Weather Forecasting, PPM models for precipitation (quantitative, probability, yes/no) and maximum/minimum temperatures are developed for monsoon season by using analyses from the European Centre for Medium-Range Weather Forecasts. The SI forecast is then obtained by using these PPM models and output from the operational NWP model at the Center. Direct model output (DMO) obtained from the NWP model and the SI forecast are verified against the actual observations. The present study shows the verification scores obtained during the 1997 monsoon season for 10 locations in India. The results show that the SI forecast has good skill and is an improvement over DMO. Copyright © 2002 Royal Meteorological Society. [source]