A Study in Objective Forecasting

1949 ◽  
Vol 30 (1) ◽  
pp. 10-15 ◽  
Author(s):  
Irving I. Gringorten
Keyword(s):  
Meteorological Parameters ◽  
Weather Station ◽  
Forecasting Accuracy ◽  
Probability Of Occurrence ◽  
Objective System

Meteorological parameters can be divided into predictors and predictands, with the former being used to predict the latter. This report describes a project in which some 20 predictors were used to predict fog and stratus at Randolph Field, Texas, in competition with usual methods of the regular weather station there. The results yielded an overall increase in forecasting accuracy and skill by the objective system. But the most important feature of the objective system is that it enables one to state the probability of occurrence of each event.

scholarly journals The Study of Terrestrial Solar Radiation in Awka Using Measured Meteorological Data

2019 ◽  
pp. 1-6
Author(s):  
Chinelo U. Ikeh ◽  
Chukwunwike C. Okeke
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Meteorological Parameters ◽  
Meteorological Data ◽  
Ground Surface ◽  
Weather Station ◽  
Wet Season ◽  
Integrated Sensor ◽  
Useful Knowledge ◽  
Energy Conversion Systems

This work investigated the terrestrial solar radiation over Awka, South Eastern Nigeria using meteorological parameters of terrestrial temperature and relative humidity collected during 2013- 2014 respectively, using Davis weather station vantage pros2 (with Integrated Sensor Suite, ISS) positioned close to the ground surface. The data were logged at 30 minutes interval continuously for each day during the period. Hourly, daily and monthly averages of terrestrial radiation during dry and wet seasons were calculated from the data obtained. The result indicated that the terrestrial radiation during dry season is generally higher than during the wet season. The month of March has the highest value of terrestrial solar radiation of 410 Wm-2 , while the least terrestrial radiation of about 381 Wm-2 occurred in August. The result also showed that terrestrial solar radiation correlates positively with water vapour and more positively with temperature at 0.57 and 0.81 coefficients respectively. The results obtained from this work provide useful knowledge that is necessary to enhance the deployment of solar energy conversion systems.

scholarly journals Some characteristics of fog over Guwahati airport

MAUSAM ◽  
2021 ◽  
Vol 59 (2) ◽  
pp. 159-166
Author(s):  
SURESH RAM ◽  
M. MOHAPATRA
Keyword(s):  
Coefficient Of Variation ◽  
Meteorological Parameters ◽  
Surface Wind ◽  
Dew Point ◽  
Statistical Characteristics ◽  
Occurrence Time ◽  
Probability Of Occurrence ◽  
Intraseasonal Variations ◽  
Duration Time

The statistical characteristics like frequencies of occurrence, time of onset, duration, time of dispersal and intensity of fog over Guwahati airport are found out and analysed using 10 years data during 1994-95 to 2003-04 for the months of November to February. Also the interannual and intraseasonal variations of occurrence of fog are analysed by calculating the coefficient of variation of monthly frequency of fog and by calculating the significant periodicities in the daily probability of occurrence of fog respectively. The meteorological parameters at 1200 UTC leading to fog in the following night or morning over Guwahati airport are analysed to find out the precursors for occurrence of fog. Statistical characteristics are given in tables and their significance discussed. It is observed that monitoring of Dew Point Depression (DPD) and surface wind can help prediction of occurrence of fog and its intensity over Guwahati airport.

Evapotranspiration Prediction Using M5T Method and Ritchie Equation for St. Johns, FL, USA

2017 ◽  
Author(s):  
Yunus Ziya Kaya ◽  
Mustafa Mamak ◽  
Fatih Ünes ◽  
Mustafa Demirci
Keyword(s):  
Wind Speed ◽  
Meteorological Parameters ◽  
Mean Absolute Error ◽  
Absolute Error ◽  
Mean Square ◽  
Weather Station ◽  
Data Set ◽  
Test Set ◽  
Determination Coefficient ◽  
Agricultural Yield

Evapotranspiration (ET) estimation takes an important role in hydraulic designs and agricultural yield. Even it is non-negligible for hydraulic designers and irrigation engineers it is not clear enough to estimate or calculate ET because of direct and indirect parameters effects. In this study Solar Radiation (SR), Air Temperature (AT), Relative Humidity (RH) and Wind Speed (U) meteorological parameters are used to create a M5T model. 1158 daily RH, U, AT and SR records are used to create model and 385 daily values are used to test it. Data set is taken from St. Johns, Florida, USA weather station. The test set is also applied to the Ritchie empirical formula. M5T model and Ritchie formula Results are compared with daily ET records using determination coefficient. Determination coefficient is found 0.966 for M5T model and 0.913 for Ritchie formula. According to the determination coefficient, Mean Square Error (MSE) and Mean Absolute Error (MAE) statistics, it is understood that M5T method can be used for daily ET estimation effectively.

scholarly journals Influence of Thermal Comfort on Health

2019 ◽  
Vol 70 (4) ◽  
pp. 1187-1191
Author(s):  
Carmen Otilia Rusanescu ◽  
Marin Rusanescu ◽  
Cosmin Jinescu ◽  
Gigel Paraschi
Keyword(s):  
Thermal Comfort ◽  
Systems Engineering ◽  
Meteorological Parameters ◽  
Meteorological Conditions ◽  
Stress Index ◽  
Cooling Power ◽  
Weather Station ◽  
Air Humidity ◽  
Human Comfort ◽  
Relative Air Humidity

The purpose of this paper is to estimate the conditions of human comfort in Bucharest. To describe the influence of the climate on human health, several indices have been developed describing the degree of physiological comfort offered by the meteorological conditions, taking into account meteorological parameters registered daily by the weather station at the Polytechnic University of Bucharest, Faculty of Biotechnical Systems Engineering: temperature and relative air humidity, wind speed. The following indices were analyzed: summer SCHARLAU index (ISE), winter SCHARLAU index (ISH), thermohigrometric index (THI), wind cooling power (skin stress index) (P), temperature equivalent to cooling wind power Tpr, to determine the influence of thermal comfort on health.

scholarly journals An evaluation of changes in the bioclimate of Łódź in the light of the tourism climate index

Turyzm ◽  
2017 ◽  
Vol 25 (2) ◽  
pp. 21-25
Author(s):  
Mariusz Siedlecki
Keyword(s):  
Meteorological Parameters ◽  
Climatic Conditions ◽  
Summer Season ◽  
Climate Index ◽  
Weather Station ◽  
Basic Information ◽  
Tourism Climate Index ◽  
Comprehensive Manner ◽  
Bioclimatic Conditions ◽  
Tourism Climate

The paper presents basic information concerning bioclimatic conditions in Łódź based on the Tourism Climate Index (TCI). The index makes it possible to assess in a comprehensive manner, based on specified meteorological parameters, the climatic conditions affecting the development of tourism. The study uses measurements from the weather station, Łódź-Lublinek, taken in the years 1966-2014. The TCI values have a distinct annual pattern with the highest values recorded in summer. The summer season has the highest frequency of days with ‘very good’ or ‘excellent’ conditions for tourism. An assessment of the variability of bioclimatic conditions indicates an increase in the number of days with high TCI values pointing to ‘very good’ or ‘excellent’ conditions for tourism and recreation.

scholarly journals Influence of data burst collision on transmission of AWS data through satellite

MAUSAM ◽  
2021 ◽  
Vol 57 (3) ◽  
pp. 499-506
Author(s):  
E. MUTHURAMALINGAM ◽  
SANJAY KUMAR ◽  
R. D. VASHISTHA
Keyword(s):  
Meteorological Parameters ◽  
Time Slot ◽  
Weather Conditions ◽  
Weather Station ◽  
Satellite Link ◽  
Surface Weather ◽  
Random Manner ◽  
Communication Equipment ◽  
Central Station ◽  
Data Burst

  lkj & Lopkfyr ekSle dsanz ¼,-MCY;w- ,l-½ og iz.kkyh gS ftlesa losndksa ds lkFk ml {ks= dh mi iz.kkyh vkSj lapkj midj.k lEc) :Ik ls dk;Z djrs gSa tks Lopkfyr :Ik ls vkSj yxkrkj lgh le;kuqlkj ml LFkku dh ekSle dh fLFkfr;ksa dh eki djrs gSa rFkk ekSle foKku ds ekin.Mksa ds vuqlkj ?kaVkokj fy, x, izs{k.kksa dks dasnz ls tqM+s mixzg ds }kjk dsanzh; LVs’ku dks rhu ckj Lo;a fu/kkZfjr i)fr }kjk vxyk izs{k.k ysus ds iwoZ 60 feuV ds vUnj fu/kkZfjr 10&10 feuV ds vUrjky ij fcuk fdlh Øe ds  vkHkklh ladsrksa dkss Hkstrs jgrs gSa A dHkh dHkh nks ;k vf/kd Lopkfyr ekSle dsanzksa ls vk¡dM+s ,d gh le; esa laizsf"kr gksus ij muds fefJzr gks tkus ds dkj.k ,- MCY;w- ,l- ds vk¡dM+s Bhd ls izkIr ugha gks ikrs gSa A eq[;r;k ,- MCY;w- ,l- ds vk¡dM+ksa dk lafeJ.k muds laizs"k.k ds le; vFkok laizs"k.k dh xfr latky esa ,- MCY;w- ,l- dh la[;k rFkk ,- MCY;w- ,l- ds vk¡dM+ksa ds lafeJ.k dh ek=k ij fuHkZj djrk gS A bl ’kks/k Ik= esa ,- MCY;w- ,l- ds vk¡dM+ksa ds mixzg ds ek/;e ls laizsf"kr vk¡dM+ksa ds lkFk vkil esa lafefJr gks tkus ls iM+us okys izHkko ds ckjs esa crk;k x;k gS A   ” Automatic Weather Station (AWS) is a system consisting of  sensors, associated field sub-systems and communication equipment, which automatically and continuously measure real time surface weather conditions and sends three times the hourly observed meteorological parameters to the central station through  satellite link in a self timed pseudo random manner in its prescribed 10 minute time slot within the next 60 minutes before the next observation takes place.  Loss of AWS data is due to collision of data burst transmitted simultaneously by any two or more  AWS.  Generally, the  collision of AWS data  burst depends upon the transmission time or transmission baud rate, number of  AWS in a network and total number of bits in  AWS data burst. This paper  describes the influence of  data burst collision on  transmission of  AWS data  through satellite.  

scholarly journals Simulation of the thermal comfort conditions of urban areas: a case study in Kyiv

2019 ◽  
Keyword(s):  
Heat Stress ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Urban Areas ◽  
Meteorological Parameters ◽  
Urban Spaces ◽  
Weather Station ◽  
Adaptation Measures ◽  
Bioclimatic Indices ◽  
The City

Formulation of the problem. Studies of bioclimate of a territory are aimed at determining the favorable and adverse impacts of various climatic factors and their combinations on the human body. Complex urban morphology has a significant impact on microclimate and, accordingly, on thermal comfort of a person in such an environment. The height of buildings, street orientation, and distance between buildings alter the solar energy inlet, affect thermal regime, transform the wind speed and direction at the street level. Studies of the bioclimatic conditions of urban areas during the warm season are highly relevant as they provide an opportunity to evaluate human thermal sensations in the city, as well as the potential effectiveness of adaptation measures to heat stress (architectural measures and measures based on the use of green areas and water bodies). The purpose of the article. The aim of this research is to simulate the bioclimate of an urban environment to determine the human thermal load in summer months based on modern bioclimatic indices and software. Methods. For the purpose of this study, a part of the territory of the Osokorky residential area of Kyiv was selected. To get values of the main meteorological parameters of the researched area, a three-dimensional, prognostic, microscale model ENVI-met was used. ENVI-met pertains to the CFD-models (computation fluid dynamics model) and is designed for microscales with a horizontal resolution from 0.5 to 10 m and with a time step of 10 seconds as maximum. The PET calculation was performed using the RayMan model. Results. A clear hot summer day (04 August 2017) was chosen for the simulation. The simulation was performed from 6:00 EEST on 4 August till 6:00 EEST the next day (output interval – 1 hour). The simulation results show that the values of the main meteorological parameters (air temperature and humidity, wind characteristics) and physiologically equivalent temperature differ significantly within urban spaces, even across small areas. The amplitudes of PET value were maximum in the daytime and made 12°–15°C. The decrease in the amplitude of the air temperature within the researched area in the evening and night hours led to a notable decrease in the PET amplitude to 2°–3°C. The analysis of the simulated PET values for the researched area confirmed that the residents of the urban areas experience the most intense heat stress while staying in the open asphalted areas during the daytime. The duration of the period with comfortable conditions during the researched day was very short – from 22:00 EEST through midnight. The range of the daily course of PET values at different points of the researched area varied from 19.4° (at point No. 7) to 37.1°C (at point No. 5 located in the well courtyard). Based on the PET values simulated for the researched area and for CAWS Kyiv was found the significant differences between thermal comfort conditions within the complex urban spaces and at the weather station. Therefore, the values of bioclimatic indices simulated based on the weather station data can not be applied with any approximation to solve scientific and applied tasks that require information on the bioclimate at particular points in the urbanized environment. To solve such tasks, it is recommended to apply modern methods – ENVI-met and RayMan models. Scientific novelty and practical significance. For the first time in Ukraine, microclimate and thermal comfort conditions within the complex urban environment has been simulated using ENVI-met and RayMan models. The results of such simulation can be used to choose heat adaptation measures which would help to increase the comfort of the urban areas. The simulation of microclimate and thermal comfort conditions of some parts of the city territory is important stage of design of the buildings, in order to choose the optimal location for buildings and trees and to create the most comfortable conditions for people.

A probability model of three potential precursors during tornado occurrences: the Italian case.

2020 ◽  
Author(s):  
Roberto Ingrosso ◽  
Piero Lionello ◽  
Mario Marcello Miglietta ◽  
Gianfausto Salvadori
Keyword(s):  
Multivariate Analysis ◽  
Statistical Analysis ◽  
Wind Shear ◽  
Meteorological Parameters ◽  
Probability Model ◽  
Conditional Probabilities ◽  
Homogeneity Tests ◽  
Probability Of Occurrence ◽  
Italian Case ◽  
The Way

<p>57 tornadoes with intensity Enhanced Fujita Scale 2 or larger that occurred in Italy in the period 2000–2018 are analysed in order to investigate the way two meteorological parameters, namely Wind Shear, calculated in 0-1 km and 0-6 km layers, and CAPE, affect their development. For this purpose, a statistical analysis, by means of homogeneity tests, conditional probabilities and a multivariate analysis via copulas is performed, using two different re-analysis datasets (ERA-Interim and ERA-5). The study indicates that: (a) tornadoes occur mostly in correspondence with positive anomalies of both variables; (b) probability of occurrence is correlated with WS, and (c) is maximum when either WS or CAPE are large. Also, the probability does not increase significantly with CAPE, although sufficiently large values are needed for tornado occurrence. These results are similar for both re-analyses we used and suggest that the selected parameters are reliable precursors for Italian tornadoes.</p>

On convenient use of nanoprobe and scanning without a stem unit in an EM-420

1987 ◽  
Vol 45 ◽  
pp. 138-139
Author(s):  
K. K. Christenson ◽  
J. A. Eades
Keyword(s):  
Wide Area ◽  
Pole Piece ◽  
Operating Condition ◽  
Objective System

One of the strengths of the Philips EM-400 series of TEMs is their ability to operate under two distinct optical configurations: “microprobe”, the normal TEM operating condition which allows wide area illumination, and “nanoprobe”, which gives very small probes with high angular convergence for STEM imaging, microchemical and microstructural analyses. This change is accomplished by effectively turning off the twin lens located in the upper pole piece which changes the illumination from a telefocus system to a condenser-objective system. The deflection and tilt controls and alignments are designed for microprobe use and do not function properly when in nanoprobe. For instance, in nanoprobe the deflection control gives a mix of deflection and tilt; as does the tilt control.

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