Showing papers on "Weather station published in 2004"

A spatial regression procedure for evaluating the relationship between AVHRR-NDVI and climate in the northern Great Plains

Abstract: The relationship between vegetation and climate in the grassland and cropland of the northern US Great Plains was investigated with Normalized Difference Vegetation Index (NDVI) (1989–1993) images derived from the Advanced Very High Resolution Radiometer (AVHRR), and climate data from automated weather stations. The relationship was quantified using a spatial regression technique that adjusts for spatial autocorrelation inherent in these data. Conventional regression techniques used frequently in previous studies are not adequate, because they are based on the assumption of independent observations. Six climate variables during the growing season; precipitation, potential evapotranspiration, daily maximum and minimum air temperature, soil temperature, solar irradiation were regressed on NDVI derived from a 10-km weather station buffer. The regression model identified precipitation and potential evapotranspiration as the most significant climatic variables, indicating that the water balance is the most imp...

High-wind-speed evaluation in the Southern Ocean

Abstract: [1] Space-based scatterometer instruments provide crucial surface wind measurements with high resolution over global oceans. Midlatitude regions in the Southern Ocean are unique places to evaluate scatterometer winds at high-wind bands because these regions host the strongest wind fields at the ocean surface. The objective of this study is to evaluate high wind speeds observed by Quick Scatterometer (QuikSCAT) wind measurements and produced by simulation models and compare them with weather station data in the Southern Ocean. The occurrence and intensity of high-wind events in scatterometer measurements are compared with that of reanalysis winds, and the spatial and seasonal variability of high-wind characteristics is examined. The results show that the speeds of scatterometer winds are similar to model simulations in the monthly mean field but consistently stronger than both European Centre for Medium-Range Weather Forecasts and National Centers for Environmental Prediction/National Center for Atmospheric Research winds in high-wind bands. When scatterometer winds are compared with the weather station observations at Macquarie Island, the present study finds no systematic bias at high-wind bands across all months. However, both weather station and QuikSCAT winds are higher than the model simulations in high-wind bands most of the time. This suggests that model simulations may underestimate surface wind strength in high-wind bands. Such underestimation would lead to up to an 80% reduction in energy flux between the atmosphere and ocean. Even though high winds occur only sporadically and the reanalysis underestimation in high wind speed is not in itself of great magnitude, they have a significant impact on global climate.

The effect of time after body discovery on the accuracy of retrospective weather station ambient temperature corrections in forensic entomology.

Abstract: Weather station data are used by forensic entomologists to estimate ambient temperatures at body discovery sites. Correlation data from sites may also be collected to correct for site and station differences. This experiment tested the accuracy over time of retrospective weather data correction using linear regression between stations and sites. Temperatures were logged at six hypothetical body discovery sites during a seven-day period for which a hypothetical body lay in situ, and a further four correlation periods. The accuracy of weather data for hypothetical body in situ periods improved after correction in 22 of 24 correlations; however, mean predicted body in situ temperatures for sites differed significantly between correlation periods. Predicted temperatures generally rose with time after body removal, which correlated with rising site temperatures accompanying seasonal change. Therefore, practitioners should be cautious in making correlations if weather patterns during correlation differ greatly from those while the body was in situ.

High Himalayan meteorology: Weather at the South Col of Mount Everest

Abstract: [1] Mount Everest is often referred to as the earth's ‘third’ pole. As such it is relatively inaccessible and little is known about its meteorology. In 1998, a portable weather station was operated at the mountain's South Col, elevation 7,986 m. We believe that this represents the highest elevation at which continuous weather data has ever been collected and thus represents a valuable dataset with which to investigate the meteorology of the high Himalaya. In this paper, we compare the observations with reanalyses from the National Centers for Environmental Prediction and the European Center for Medium-Range Weather Forecasts. We find that both reanalyses capture much of the synoptic-scale variability in the temperature and pressure at the South Col site, especially in the pre-monsoon season. Furthermore, we show that an observed weather event was the result of convection associated with a jet streak and an intrusion of stratospheric air into the upper-troposphere.

Mean gust factors in complex terrain

Abstract: Gust factors are analyzed for wind speeds greater than 10 m/s in a large set of data from automatic weather stations in the complex terrain of Iceland The mean gust factors appear to be independent of the static and dynamic stability of the atmosphere, suggesting that gravity wave dynamics may compensate for the damping of turbulence in stably stratified flows The mean gust factor depends however on wind speed and nearby topography and decreases regularly with increasing wind speed and station altitude High mountains close to the weather stations give strong downstream wind gusts In a subset of the data, containing only statically stable flows, mean gust factors of 16 or more may be obtained if an upstream mountain rises at least 200 m above the weather station and the distance to the mountain is less than 10 times its height above the station

Climate and climatic variability at Lake Myvatn

Abstract: The climate of the Lake Myvatn region is examined through the use of weather station data, using the years from 1971 to 2000 as a reference period. Variations in mean monthly temperature and precipitation at Reykjahlid (Myvatn) are compared with variations at seven other weather stations in north east Iceland. The area is drier and colder than coastal stations and exhibits a seasonal cycle in temperature that is larger than found at the coast. The temperature is significantly influenced by the number of sunlight hours only during the summer months. During summer, the influence of a sea breeze circulation can be clearly identified.

Aerial chemical application and control method

Abstract: A chemical distribution control and guidance system operates for controlling the distribution of airborne product via an aircraft passing over a target. A weather station is positioned at various altitudes for use in determining an appropriate aircraft altitude for distributing the chemical to the target. A second weather station positioned near the target transmits weather data in real time to a central communications station and the aircraft for providing guidance in accurately, safely and effectively distributing chemicals onto the target.

Premise evacuation system

Abstract: An evacuation system using a combination of elements, such as an on-site weather station ( 2 ), a computer system ( 1 ) with proprietary software, sensors and other elements to determine a safe direction of evacuation from a premises ( 11 ) in case of a threat, use indicators to determine the direction of evacuation and notification of parties external to the premises ( 11 ) of evacuation.

Artificial neural networks for meteorological nowcast

Abstract: Weather forecast are a typical problem where a huge amount of data coming from different types of sensors must be elaborated by means of complex, time-consuming algorithms. This work presents a new approach where the data fusion is performed with soft computing techniques. A statistical-neural system is used to "nowcast" meteorological data measured by a weather station. The system is able to forecast the evolution of these parameters in next three hours, giving precious indications about the possibility of rain, ice, and fog in next future.

Cross-Sectional Analyses of Climate Change Impacts

Abstract: The authors explore the use of cross-sectional analysis to measure the impacts of climate change on agriculture. The impact literature, using experiments on crops in laboratory settings combined with simulation models, suggests that agriculture will be strongly affected by climate change. The extent of these effects varies by country and region. Therefore, local experiments are needed for policy purposes, which becomes expensive and difficult to implement for most developing countries. The cross-sectional technique, as an alternative approach, examines farm performance across a broad range of climates. By seeing how farm performance changes with climate, one can estimate long-run impacts. The advantage of this approach is that it fully captures adaptation as each farmer adapts to the climate they have lived in. The technique measures the full net cost of climate change, including the costs as well as the benefits of adaptation. However, the technique is not concern-free. The four chapters in this paper examine important potential concerns of the cross-sectional method and how they could be addressed, especially in developing countries. Data availability is a major concern in developing countries. The first chapter looks at whether estimating impacts using individual farm data can substitute using agricultural census data at the district level that is more difficult to obtain in developing countries. The study, conducted in Sri Lanka, finds that the individual farm data from surveys are ideal for cross-sectional analysis. Another anticipated problem with applying the cross-sectional approach to developing countries is the absence of weather stations, or discontinued weather data sets. Further, weather stations tend to be concentrated in urban settings. Measures of climate across the landscape, especially where farms are located, are difficult to acquire. The second chapter compares the use of satellite data with ground weather stations. Analyzing these two sources of information, the study reveals that satellite data can explain more of the observed variation in farm performance than ground station data. Because satellite data are readily available for the entire planet, the availability of climate data will not be a constraint. A continuing debate is whether farm performance depends on just climate normals-the average weather over a long period of time-or on climate variance (variations away from the climate normal). Chapter 3 reveals that climate normals and climate variance are highly correlated. By adding climate variance, the studies can begin to measure the importance of weather extremes as well as normals. A host of studies have revealed that climate affects agricultural performance. Since agriculture is a primary source of income in rural areas, it follows that climate might explain variations in rural income. This is tested in the analysis in Chapter 4 and shown to be the case. The analysis reveals that local people in rural areas could be heavily affected by climate change even in circumstances when the aggregate agricultural sector in the country does fine.

War North of 80: The Last German Arctic Weather Station of World War II

Abstract: Obtaining weather data was vital for military operations in Northwestern Europe during World War II. In an effort to secure this data, the German Navy and Air Force secretly established manned weather stations in East Greenland, Svalbard, and Franz Josef Land. War North of 80: The Last German Arctic Weather Station of World War II is the personal story of Wilhelm Dege, the leader of the last weather station, code-named "Operation Haudegen." With a detailed introduction, Barr's translation offers Engish-speaking readers a rare glimpse into the Germans' account of weather activities during World War II in the Arctic. An epilogue written by Dege's son offers insight into the various fates of the expedition members who worked alongside his father.

Forecasting terrain-dependent weather conditions: details of a model chain sequence

Abstract: To forecast terrain-dependent weather conditions with a focus on hazardous road conditions (such as icing and high winds), a model chain has been developed. In this chain, a series of three weather modeling programs have been linked together, successively nesting the mesh of one regional model inside another. The three programs in use are Eta, with computational analysis provided by the National Center for Environmental Prediction (NCEP); ARPS (Advanced Regional Prediction System), with computational analysis provided by Meridian Environmental Technology; and RadTherm/RT, with computational analysis provided by Montana State University (MSU). Once Eta data are available, they are downloaded from NCEP servers to Meridian servers and used to run a sequence of ARPS models, to represent terrain-dependent changes in the meteorological conditions down to resolutions of 1 km. As each analysis progresses, successive forecast conditions are written to files and passed to computational servers at MSU. At MSU, these meteorological files are used to define environment conditions (such as long- and short-wave radiation, cloud cover, precipitation, and convective effects) in RadTherm. Successive downloads are then used to run RadTherm models somewhat in parallel with, though slightly behind, each ARPS forecast. As successive forecast models become complete, forecast data are graphed alongside real-time measured data and posted on the Internet. To allow viewers to evaluate the validity of the current forecast, graphs corresponding to weather station sites are updated hourly, typically by extracting measured data from websites associated with the given station. These same data sets can then be compared on a weekly basis for long-term performance evaluation and improvement.

The Columbia, Missouri, Heat Island Experiment (COHIX) and the Influence of a Small City on the Local Climatology

Abstract: The heat island effect is a well known feature in the microclimate of urban areas but only a few studies have addressed the effect for smaller urban areas. We examine here the impact of Columbia, Missouri and the University of Missouri campus on the microclimate (temperature and precipitation) of central Missouri. We purchased twenty Radio Shack® digital Max/Min thermometers and ten standard raised-edge rain gauges and these were given to students, staff, and faculty participants who were chosen for their reliability to provide daily data over the course of a year, site the instrument, and their location (in order to provide reasonable coverage locally). We also included information provided by automated and cooperative weather stations, and the weather station at the regional airport located 11 km (7 miles) southeast of Columbia. Our results indicate that the city has no discernable impact on the distribution of monthly precipitation totals. We found a distinct urban influence on the local surface temperatures, and the inner city region and the urbanized area of south Columbia were approximately 2 – 3 F (1.0 – 1.5 C) warmer in the mean than the surrounding environment. This difference grows to 3 – 6 F (1.5 3.5 C) when comparing the mean of the warmest station in the city to that of coolest station outside Columbia. We also observed a seasonal influence, as the heat island effect was more evident in the mean monthly maximum (minimum) temperatures during the warmest (coldest) months.

Raising the Reliability of Overhead Transmission Lines under the Action of Atmospheric Loads

Abstract: Problems of reliability of overhead transmission lines (OTL) under the action of atmospheric loads are considered. It is assumed that the integral distribution function of, for example, ice loads, obtained from data of weather stations is a random statistical function that characterizes the frequency of an event (specific ice load) at a point (weather station area). The general population of statistical data is the most reliable base for analysis. Since the atmospheric loads are distributed in space and act on spatially distributed OTL systems, it is recommended to evaluate the proof load and the yearly reliability of OTL in terms of one integral statistical function composed of annual load maxima measured by weather stations located closest to the annual extremum of the ice load on a territory possessing common features (flat-bottom land, low land, elevation) that range within no more than 150 m with respect to the altitude. It is suggested that the “Methodological Recommendations on Zoning of Atmospheric Loads on OTL Systems” should be updated with allowance for the obtained data.

Temporal - Spatial Analysis of Temperature and Its Effect on Climate and Water in Qinghai Gonghe Basin

Abstract: In the northeastern part of Qinghai-Tibetan plateau lies Gong-he basin. The paper discusses the temporal-spatial characteristic of temperature and its effect on climate and water according to the meteorological data (1953-2001) from three weather stations and soil water material (1980-2002) in Qiabuqia weather station by time series method, DEM and Penman-Mon-teith equation. The results show that annual temperature time series are not stationary, but with linear upward trend; and annual average temperature in Chaka and Qiabuqia and Guinan is increasing by 0.0247,0.0422 and 0.0272℃ respectively per year according to the linear model in Gong-he basin; furthermore, the spatial distribution of annual average temperature can be simulated by using multivariable linear model based on digital elevation model (DEM 100×100m2) and by using the data at three permanent weather stations and more than ten temporary weather stations. The two big sand bands(Shazuyu-Tala and Mugetan) is in the higher scope of temperature(1.0-4.0℃ and 1.0-2.9℃) according to the simulated result, and there is a direct correlation between annual temperature and potential evapotranspiration in space; with temperature rising, the saturated difference of water pressure and potential evapotranspiration increases gradually, and soil water decreases in topsoil; so it makes the climate drier, and desertification become more serious gradually in the future in Gong-he basin in Qinghai province. But in short-term, especially in the period of research, the change of climate is very slight, so the cause of desertification needs to be analyzed further in Gong-he basin.

Temporal method for IR minefield feature detection

Abstract: The overall objective of this work is to investigate the possibilities of using airborne IR sensors for the purpose of detecting minefield features, such as land mines. A method is proposed for temporal analysis by extracting relevant information from diurnal IR images utilizing a combination of thermodynamic modelling, signal and image processing. This paper presents results from a field test of level 2 survey in May 2003 of suspected mine-polluted areas in Croatia. Airborne data was acquired using an IR sensor mounted on a rotary wing UAV. A weather station was used to collect weather data, and pt-100 temperature sensors recorded the temperature gradient in the soil and in reference markers that were used for calibrating the IR camera. The proposed method compares simulated temporal temperature with image data collected at several times during a diurnal cycle from the same area, pixel by pixel. The images are co-registered and calibrated with respect to reference values. The numerical model is based on physical laws and is set with relevant properties, geometries, materials, surface coefficients and the influence of the actual weather sets the boundary conditions. This paper shows some results from using temporal features for detection of different relevant objects in a real minefield.

Calculation of Designing Wind Velocity and Wind Observation at the Runyang Yangtze River Road Bridge

Abstract: This paper analyzes the wind speed of Wind Speed Monitor Station at Runyang Bridge and Wind Speed Monitor Station at Weather Station of Dantu.The monitoring data of both stations showed positive correlation. By fitting extremum frequency distribution with Gumbel Distribution Function principal wind uelocitiesin different recurrence period are claculated. The calculated results provide credible technical guide to construction of Runyang Bridge and ensure wind resistance safety.

Projected state of road weather monitoring in finland in 2007

Abstract: The aim of the projected road weather data monitoring project is to define the objective state of weather and road weather data monitoring for 2007. The data in this context include road weather station data and camera pictures, satellite and radar pictures, weather forecasts in different forms, as well as data on road conditions and road weather forecasts. The definition of the objective is a tool for developing the monitoring system. Six use cases of the monitoring system defined the requirements for the intended state. The most important new requirements came from road maintenance quality control use case. The most detailed requirements came from the traditional maintenance realization. In addition the traffic control has its own requirements for those road sections with variable speed limits and information boards. The present monitoring system meets many of the future requirements. The projected state is illustrated by defining the new and enhanced parts of the system in 2007. All together nine new parts were defined, including issues like enlarged and better-equipped road weather stations and camera network, improvements to data storages, processing, and presentation, and also a new centralized data transmission system for receiving and delivering road weather data. In addition to the implementation projects a number of development ideas were proposed. The most important future development items are road weather models and forecasts as well as floating car road weather monitoring.

Pace University Weather Station Website

Abstract: comparison of the existing systems. We discuss all the features and functionalities provided by these websites and discuss the importance of these features. We describe the technologies used to build a successful website and evaluate some existing websites based on their technical features. We make a heuristic evaluation and cognitive walkthrough of one of the best weather station websites. We then make a buy/build decision concerning the work required on the Pace University weather station. The purpose of the project is to provide the capability to view the data that is available and visible at the Pace University base weather station in Pleasantville via a web interface in an easy-to-use manner. The resulting weather station website will display the following information: • Temperature • Humidity • Wind speed • Wind direction • Barometric Pressure • Rain collected

Forecasting Fog at Donmuang Airport in Winter

Abstract: A method has been developed for predicting visibility over Donmuang airport at 0700 a.m. in winter from surface meteorological observations at 0100 a.m. and 0500 a.m. using multiple linear regression. Data from the Thai Meteorological Departments weather station at Bangkok International Airport in December, January and February were used. For each month two models were found: one containing all the available surface observations, and one omitting the insignificant observations. The model forecast consists of the probabilities of fog, poor visibility, and good visibility, respectively.

The Temperature Integrated Forecast Method in County Stations

Abstract: This article have introduced the temperature integrated forecast method with manifold element regression, by using of the weather stations apiece report temperature, and the maximum temperature and the minimum temperature of country weather station.

Estimating Method of Regional Evapotranspiration over South Ningxia Using Satellite Remote Sensing Data

Abstract: It is a very complicated problem to estimate evapotranspiration (ET) over a large area natural surface.Based on the information of satellite remote sensing and geography,the natural surface is divided into 6 categories,and then the evapotranspiration for each category is calculated.By analyzing the satellite remote sensing and weather station data,the result of regional evapotranspiration over south Ningxia is given,and the result is also analyzed and verified.

Winter classification of air masses and weather types for the forecasting of hospital admissions for myocardial infarction in florence, italy.

Abstract: 1. ABSTRACT Recently, interest in the impact of the weather and climate on human health has become an issue of much greater significance. The aim of this study was to evaluate the relationship between the risk of hospital admission for myocardial infarction and daily weather conditions, according to a synoptic climatological approach. Data for daily admissions for myocardial infarction were provided by the Administration of Careggi Hospital in Florence for the period 1998-2003. Hourly meteorological data was obtained from a weather station located in the main urban park of Florence and managed by the Institute of Biometeorology of the National Research Council. The analyses were concentrated on winter season, when the maximum peak of hospitalization for myocardial infarction occurred. A principal component analysis and a successive clustering technique was applied to identify typical air masses characteristics of the Florentine area. A multiyear comparison of MI admissions between air mass types was made by the calculation of a myocardial infarction admission index. Sequences of air mass types and their impact on hospitalizations were also investigated. Two antyciclonic air mass types (the continental anticyclonic and the anticyclonic mixed tropical maritime and continental) and the cyclonic one, were often associated with high mean daily admissions for myocardial infarction, especially when consecutive days with these air mass types occurred.

GIS Data Model

Abstract: The intent of this poster presentation is to demonstrate the various GIS data layers used in the documentation and analysis of snow profiles and avalanche paths. These posters will present a flow chart defining the workflow of this data in a GIS. The historical avalanche path data is loaded in to a database that can relate the hard copy snowpit and weather data. These data layers can be displayed over other GIS base layers such as DEM, DRG, DOQ, soils/geology, and vegetation cover. Integration of realtime weather and snow profile data can be added to this for analysis. I will correlate these types of data and explain how they could be used in analysis to enhance predictions and provide more information. Digital data collection tools will be displayed that can load new data directly in to a GIS Database with little hand entry. For many years the Swiss, Canadian and other snow scientist have been using GIS to monitor, document, and model avalanche occurrence, snow profiles, and weather. In the United States the use has been limited to only a few areas. The recent advances in technology and the lowering of overall cost have made it so that much can be done. This presentation will attempt to familiarize the viewer with the data types and applications. Historical (legacy) data can be used as references in the GIS when the hand drawn avalanche paths are digitized and loaded in to a geodatabase. Avalanche path data (consisting of avalanche archive records and photographs, avalanche mapping of starting zones, size, frequency and area extent of danger), snowpit, and weather data can be converted from hard copy to digital. The weather data is often in digital and can be linked or loaded to the avalanche and snowpit profile database as well. The base data layers such as DRG (digital topo map) and DOQ (aerial photography) provide visual information and the ability to identify avalanche terrain. These can also help in referencing the topography of the avalanche areas. The DEM (digital elevation model) allows various terrain analyses: mean slope, minimum slope, maximum slope, mean aspect, and curvature. When the avalanche path data is overlaid on the DEM it can be analyzed using the nearest neighbor model. This data type is becoming more readily available and at higher resolution (most of the US is now available at 10m and there is 2 meter data for some areas) and accuracy. Much of it is free from the USGS or the USDA as well as many state GIS data clearing houses. Other important GIS data layers are the hydrography (rivers, streams and lakes), geology, vegetation, tree ring, buildings and roads. Hydrography data shows drainages where avalanches could be constructed by potential terrain traps. Vegetation and geologic layers and often combined with slope angles and curvature to help gauge friction parameters (destructive force) from the various sizes of the volume of the avalanche’s release. Tree ring data can help document and predict the frequency and sizes of avalanches along their tracks. Building zoning and road data can define potential areas that will suffer destruction. The analyst can use the GIS to combine this data with real time weather and snow data of the area by modern digital collection tools to assess risk and level of danger. The advent of pocket computers and mobile GIS/GPS software has made it possible to collect digital field data about avalanche paths and snow profiles. This data can be integrated with the historical avalanche database after it has been brought into the digital framework. Likewise it is possible to take the historical data into the field for a reference and create a new file for the latest occurrence. By collecting a new weather and profile and give it a spatial position with a GPS point it possible to hyperlink snowpit profile graphs, photographs, and weather station locations to a specific spatial place. This is useful in viewing the changes to a particular place over a season and the ability to quickly call up past information. Remote weather stations can send weather data every half hour by phone line or wireless transmission. Through the internet a weather program called Meteorologix can bring real time Doppler radar weather images directly into the GIS software view window. As well as digital collection by hand held computer from traditional weather and snow observation sites. With these

Comparação microclimática de ambiente de várzea e de posto meteorológico Microclimatic comparison of the environment of weather station and floodplains

Abstract: Foi realizado um estudo visando comparar os ambientes de varzea sistematizada e de posto meteorologico, no municipio de Mococa (SP), por meio de medicoes de temperatura e umidade relativa do ar, radiacao solar global e velocidade do vento. No ambiente de varzea, foi medido tambem o saldo de radiacao. A comparacao de medias foi feita por analise de dados pareados, de outubro a marco (representando as condicoes de primavera/verao) e de abril a julho (outono e inverno). A evapotranspiracao na escala diaria foi estimada pelo metodo de Penman-Monteith, adotado como padrao pela FAO. No periodo outono-inverno (O-I), observou-se que, para a temperatura maxima do ar, a diferenca media entre os ambientes foi de 0,1 oC; para a temperatura minima do ar, a varzea apresentou media inferior de 3,4 oC, enquanto no periodo de primavera-verao as temperaturas maximas, na varzea, foram, em media, 0,9 oC mais elevadas que no posto meteorologico. Os valores de evapotranspiracao, no periodo de primavera/verao, os dois ambientes analisados foram muito semelhantes. A evapotranspiracao em ambos os ambientes variou entre 1,0 e 7,8 mm por dia com valores maximos ocorrendo no periodo outubro/novembro. Durante o outono/inverno as estimativas feitas para o posto meteorologico foram superiores em 1,6 mm por dia as da varzea. No periodo de outono-inverno foram mais acentuadas as diferencas entre varzea e posto meteorologico.