摘要:

AbstractFour Meteorological Data Distribution (MDD) systems were installed in African meteorological services in late 1992. The PC‐based systems are inexpensive and are intended to he sustainable technology. The MDDs were well received and in each country the MDD immediately enhanced the local information base, improving the quantity of station data available as well as providing processed products. The MDDs have enabled the recipient meteorological departments to improve the services they offer to government, to aviation and to the public. The Natural Resources Institute (NRI) is now working with local users to develop further applications. The future of MDD in Africa is not yet clear. MDD may be integrated into multi‐tasking workstations but such technology may not yet be appropriate for small meteorological servi

ISSN:1350-4827    

DOI:10.1002/met.5060010201

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractWeather warnings are of great importance for the protection of life and property. The Storm Warning Observatory at Lake Balaton was founded with the aim of providing holidaymakers with warnings 1‐2 hours ahead of expected wind gusts exceeding 12 or 17 ms−1. As a result of successive investigations an objective decision procedure has been developed which combines methods based on conventional data with the use of radar data. This procedure can be executed interactively on a computer. The permanence of wind hazards was investigated during frontal and convective weather situations using radar data and synoptic observations. The resulting distribution functions of empirical probability for the permanence of wind hazards associated with cumulonimbus can be used for the further optimisation of the decision met

ISSN:1350-4827    

DOI:10.1002/met.5060010202

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThis paper sets out to show that even with a winter climate which is relatively mild, compared with conditions experienced by some European countries, Devon can save money and minimise the effect on the environment by employing sophisticated technology together with a forecast aimed specifically at road‐surface conditions. In Devon, on many nights during the winter, the forecast minimum road temperatures hover around freezing and therefore the decision to salt is not straightforward. A system has been developed in Devon which combines use of the forecast with sensor, radar and satellite data, thermal maps and a Control and Information Room which is manned 24 hours a day. Staff in the control room monitor road conditions so that salting operations can be properly timed or cancelled if conditions are ‐warmer than expected. The system has been successful in realising both economic and environmental benefits to Devon and has provided an effective and efficient service to the public in the cou

ISSN:1350-4827    

DOI:10.1002/met.5060010203

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe purpose of this paper is to give a general description of the project TERRA del Sud and to present the activities carried out as far as meteorological weather forecasting is concerned. TERRA del Sad it a system for the aquisition, processing and dissemination of environmental data, and is designed mainly to support agricultural practices and decision making in agricultural planning. Several meteorological procedures have been developed for weather forecasting. A system for the processing and displaying of meteorological images and data has been developed for analysis and nowcasting and simple methods of statistical post‐processing are applied to the ECMWF model outputs for short‐ and medium‐range forecasting of precipitation and temperature. Some preliminary results and future developments are pres

ISSN:1350-4827    

DOI:10.1002/met.5060010204

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractBelgium's Civil Protection organisation, like any other public service these days, has to reorganise itself because of changes m the socio‐economic climate. In a changed society where industrial and technological risks are perceived more sharply, this organisation, which was born in the Cold War era, is nowadays more concerned with fighting industrial accidents and coordinating emergency planning activities. In this context, a project for a digitalised emergency planner is being launched with the support of the European Community. In this so‐called GIDS system, a dispersion module is indispensable. Because of the urgency of the needs of risk management, the meteorological input for it will have to he provided very rapidly, frequently and m great detail. To meet these specific needs the meteorological services may have to consider offering new kinds or new formats of ‘nowcast’ calculations. The conclusion is that, with the various meteorological services rethinking their tasks, new‐technology projects such as the CIDS system may engender a new kind of coll

ISSN:1350-4827    

DOI:10.1002/met.5060010205

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractBased partly on more than 20 years of evaluating local weather forecasts in Germany, a comprehensive analysis of the verification results of synoptic, statistical and short‐ and medium‐range forecasts was carried out in order to obtain some insight into the present ‘state of the art’ in local weather forecasting. This ‘state’ is characterised by (a) striking improvements in skill, especially for the three‐to‐six‐day period; (b) an absence of significant progress in very‐short‐range forecasting, especially for aviation purposes and rare events; (c) an important role for statistical interpretation of medium‐range forecasting products; (d) an increasing importance of direct model output for some short‐range predictands; and, finally, (e) the urgent necessity to combine all the relevant forecast information m an op

ISSN:1350-4827    

DOI:10.1002/met.5060010206

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractA numerical road‐ice prediction model is further developed to predict surface temperature and surface state for porous asphalt pavement, which is significantly colder at night and warmer at daytime than conventional asphalt pavement. The model is validated against temperature measurements on both porous and conventional asphalt pavements, using actual input data for the complete winter 1992/93. The validation of model rum at noon shows that, on average, the model has a near‐zero bias for minimum, maximum and overall hourly temperature forecasts. The model has the smallest standard deviation (0.78 °C) for minimum temperature forecasts and the largest standard deviation (1.92 °C) for maximum temperature forecasts. Nearly 90% of frost days are predicted. Model runs with different start times at 1200 1500, 1900 and 0000 show consistently good re

ISSN:1350-4827    

DOI:10.1002/met.5060010207

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractA simple cyclone model is presented as a new and modern tool for use in education and training in synoptic‐dynamic meteorology. The model has been programmed on an IBM‐compatible personal computer under DOS and is used as a teaching tool by the Royal Dutch Air Force and at the Department of Meteorology of Wageningen Agricultural University. The model is based on an approximate analytical solution of the equations of motion. This solution is capable of generating a realistic mature mid‐latitude cyclone and its development in time. Several basic parameters of the solution can be varied, leading to different characteristic types of cyclone structure and develo

ISSN:1350-4827    

DOI:10.1002/met.5060010208

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractIf the weather patterns that exist during an ocean crossing are known at the outset of a voyage the process of ascertaining an ‘optimal route’ would be precise and certain. The basis of advice to ship‐masters is the optimal route (related to a stated objective function of time, fuel or total cost); this is calculated for the weather predicted at the outset of a voyage and is updated as the ocean crossing proceeds. The hypothesis is that the accuracy of the optimal route calculated at the outset will be inversely proportional to the length of the voyage, as weather prognoses similarly deteriorate with time. This hypothesis is tested by analysing environmental data typically used in the routeing process. A brief description of the ORION automated system is given, with the implications that the attendant environmental data have for the optimal routeing algorithm. Data sources so used are listed, including the extended data (that in excess of ten days). A verification study of these data is described with comparisons of some of the products used, together with a brief analysis of the observed errors and accuracies, in order to indicate confidence levels in the routes provided. An example of a simple verification of moving average data is shown. A routeing study is included in order to illustrate the merit of using medium‐range forecast data and longer‐range extended data in t

ISSN:1350-4827    

DOI:10.1002/met.5060010209

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractIn order to help in fighting forest fires, South‐cast Météo‐France has, for the past 20 years, been issuing forecasts for small zones about 900 km2in size. These zones have been defined by taking into account relief, vegetation and micro‐climate. The main beneficiary of this, assistance is the Civil Security Force. This article describes the meteorological assistance that is given and the way this has developed, and makes an attempt to measure the economic impact of this assistance. It is relatively easy to estimate the direct costs of supplying the forecast services, the costs of the fire prevention implemented as a consequence of these forecasts, and the cost of fire fighting and replanting. Savings made to the prevention system and the area of forest due to the forecasts arc more difficult to evaluate. Nevertheless, estimates of these amounts ar

ISSN:1350-4827    

DOI:10.1002/met.5060010210

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY