Search results for "WES"
showing 10 items of 1585 documents
Interannual and decadal SST-forced responses of the West African monsoon
2010
International audience; We review the studies carried out during the African Monsoon Multidisciplinary Analysis (AMMA)-EU on the changes of interannual sea surface temperature (SST)-West African monsoon (WAM) covariability at multidecadal timescales, together with the influence of global warming (GW). The results obtained in the AMMA-EU suggest the importance of the background state, modulated by natural and anthropogenic variability, in the appearance of different interannual modes. The lack of reliability of current coupled models in giving a realistic assessment for WAM in the future is also stated.
Expected future changes in the African monsoon between 2030 and 2070 using some CMIP3 and CMIP5 models under a medium-low RCP scenario
2012
[1] The accuracy of African Monsoon (AM) simulations together with expected future changes are presented using eight available CMIP5/AR5 AOGCMs under the RCP4.5 emission scenario and eight CMIP3/AR4 AOGCMs under the A1b scenario, with a multimodel approach and the “one model one vote” concept. The results refer to the ‘present’ period (1960–1999) and to a ‘future horizon’ (2031–2070), and are discussed in terms of monsoon dynamics and climate change. Overall the new simulations seem more realistic. They exhibit more accurate rainfall patterns, although some biases reported in CMIP3 models remain. The future changes show an inverse tendency regarding rainfall amounts with less (more) rainfal…
Heavy daily precipitation distribution in east-central Franceand west European meteorological patterns
2000
Principal Component Analysis is used to link the spatial distribution of Heavy Daily Precipitation (HDP) in East-Central France with meteorological patterns of the Meteo-France automatic classification, which takes into account 15 different meteorological parameters (e.g. geopotential heights at different levels, humidities, pseudo-adiabatic temperatures) over Western Europe. Every parameter is classified in 10 classes, or synoptic patterns. The annual PCA shows 3 dominant modes of HDP distribution, explaining more than 90% of the total variance. Associated atmospheric situations are obtained by using the scores of the 150 classes (10 per meteorological parameter). Other PCAs (i.e., half-an…
Classification of intense rainfall days in southern West Africa and associated atmospheric circulation.
2020
Daily rainfall in southern West Africa (4&ndash
Tropopause level Rossby wave breaking in the Northern Hemisphere: a feature-based validation of the ECHAM5-HAM climate model
2012
Breaking synoptic-scale Rossby waves (RWB) at the tropopause level are central to the daily weather evolution in the extratropics and the subtropics. RWB leads to pronounced meridional transport of heat, moisture, momentum, and chemical constituents. RWB events are manifest as elongated and narrow structures in the tropopause-level potential vorticity (PV) field. A feature-based validation approach is used to assess the representation of Northern Hemisphere RWB in present-day climate simulations carried out with the ECHAM5-HAM climate model at three different resolutions (T42L19, T63L31, and T106L31) against the ERA-40 reanalysis data set. An objective identification algorithm extracts RWB …
Sea Surface Temperature Fields Associated with West African Rainfall Anomaly Types
1996
Abstract Four West African rainfall anomaly types are defined in relation to the northern summer rainfall departure signs in the Sahel and in the Guinean region in order to investigate the statistical links between interannual variability of West African rainfall and sea surface temperature (SST) through the period 1950–90. Composite analysis depicts the setup of four different mean SST anomaly fields. Drought over all of West Africa is associated with the growth of positive SST anomalies in the eastern Pacific and in the Indian Ocean, and negative SST anomalies in the northern Atlantic and in the Gulf of Guinea. In contrast, drought limited to the Sahel corresponds mostly to a northward ex…
Performance of DEMETER calibration for rainfall forecasting purposes: Application to the July–August Sahelian rainfall
2008
International audience; This work assesses and compares the skill of direct and model-output-statistics (MOS) calibrated hindcasts of the July–August rainfall amounts for the dry period 1980–2000 over the Sahel issued from the Development of a European Multimodel Ensemble System for Seasonal to Interannual Prediction (DEMETER) experiment, with the aim to highlight among the simulated parameters, i.e., those potentially relevant for rainfall forecasts purposes. Three approaches were used: the DEMETER (1) direct rainfall, (2) MOS-calibrated rainfall, and (3) MOS-calibrated atmospheric dynamics and energy. Canonical correlation analyses (CCA) were employed in the two latter approaches to calib…
Attitudes, behaviours and perceptions of Italian General Practitioner trainees towards influenza vaccination in Western Sicily (Italy)
2012
Background: General practitioners (GPs) have to be considered as key figures of health promotion among health care workers since they are strongly asked to recommend influenza vaccination to their patients and perform on them. Despite this consideration, GPs have influenza vaccination rates that are significantly below the 75% coverage proposed by International Public Health guidelines. In order to increase future coverage of influenza vaccination within GPs, and through them within the population, the aim of this study was to assess determinants associated with influenza vaccine uptake among GP trainees. Methods: A survey was carried out on GP trainees attending the training course in Comm…
Orationes tres
1594
Mollīna tipogrāfijā nodrukātas Orationes tres: trīs runas, ko turēja sholarhi (Rīgas rātes prokonsuls Nikolajs Eke; 1541-1623 un sindiks Dāvids Hilhens; 1561-1610) un Domskolas rektors Johans Rīvijs (Rivius, 1528-1596, Domskolas rektors (1589) un inspektors (1594)) reorganizētās Domskolas atjaunošanai veltītajā svinīgajā pasākumā 1589. gada 15. jūlijā. Vairāki grāmatas eksemplāri bija domāti dāvināšanai ievērojamām Rīgas personām, tāpēc iesieti grezni: brūnā ādā, ar Rīgas ģerboni zelta iespiedumā uz vāka. Runu tekstus papildina tabulas, kur fiksēts visu triju skolas klašu stundu plāni. Runu izdošana un iespiešana ilga četrus gadus. Izdevums kavējās dēļ burtstabiņu trūkuma grieķu teksta iesp…
Diffusion of Drone Journalism: the Case of Finland, 2011-2020
2020
This article details Finnish news organizations’ adoption of drones for journalistic purposes from 2011 to 2020. The theoretical starting point of the article is Rogers’ (1962) diffusion of innovations theory, which explains how new ideas and technologies spread in societies. The main empirical data for the study were derived from a phone survey conducted among the 80 most popular newspapers in Finland. The findings reveal that drone journalism in Finland has already diffused from a few pioneering organizations to a large number of newsrooms, including regional, mid-sized newspapers. Most of the newspapers are either using in-house drones, buying commissioned images, or using both strategie…