scholarly journals Wind speed and direction characterization in Tangará da Serra, Mato Grosso state, Brazil

2010 ◽  
Vol 25 (3) ◽  
pp. 359-364 ◽  
Author(s):  
Rivanildo Dallacort ◽  
Patrícia Simone Palhana Moreira ◽  
Miriam Hiroko Inoue ◽  
Dionei José Silva ◽  
Ilio Fealho Carvalho ◽  
...  

The aim of this work was to determine the predominant winds speeds and directions in the Tangará da Serra region, locate in Southwest of Mato Grosso State, Brazil. So that, it was used meteorological time series from 2003 to 2008, collected through an Universal Anemometer, installed 10 meters above the ground surface in the Automatic Weather Station by the INMET - Meteorology National Institute at the Mato Grosso State University - UNEMAT (14º39' S, 57º25' W and 321,5 m). The predominant winds directions were characterized by the frequency analysis of daily observations from each month of the year. The months that showed higher speeds were: May, June, July, August and September. March showed the lower average and the lower maximum speeds. In all months, the diurnal winds were higher than the nocturnal ones, the strongest winds had occurred during the warmer hours of the day, i.e. from 13:00 to 17:00 h (local time). The monthly maximum gusts had varied from 15.1 m s-1 in June to 30.7 m s-1 in August. In most months of the year there is a predominance of winds from the Northeast (NE), except August and September period, when the winds predominant directions is from the South (S).

2021 ◽  
Vol 768 (1) ◽  
pp. 012008
Author(s):  
Zhen Yang ◽  
Husheng Zhang ◽  
Qiang Wang ◽  
Cuicui Li ◽  
Wenlong Xu ◽  
...  

2012 ◽  
Vol 58 (212) ◽  
pp. 1144-1150 ◽  
Author(s):  
Robert S. Fausto ◽  
Dirk Van As ◽  
Andreas P. Ahlstrøm ◽  
Michele Citterio

AbstractWe present a method of measuring ice ablation using an absolute pressure transducer as part of an automatic weather station (AWS) system, which we have installed in 17 locations on the Greenland ice sheet. The pressure transducer assembly is drilled into the ice, enclosed in a hose filled with antifreeze liquid. The pressure signal registered by the transducer is that of the vertical column of liquid over the sensor, which can be translated to depth, and ice ablation rate, knowing the density of the liquid. Measuring at sub-daily timescales, this assembly is well suited to monitoring ice ablation in remote regions, with clear advantages over other, well-established methods. The pressure transducer system has the potential to monitor ice ablation for several years without re-drilling, and the system is suitable for high-ablation areas (>5ma-1). A routine to transform raw measurements into ablation values is presented, including a physically based method to remove air-pressure variability from the signal. The pressure transducer time series is compared to that recorded by a sonic ranger for the climatically hostile setting on the Greenland ice sheet.


2020 ◽  
Vol 59 (12) ◽  
pp. 2113-2127
Author(s):  
Lea Hartl ◽  
Martin Stuefer ◽  
Tohru Saito ◽  
Yoshitomi Okura

AbstractWe present the data records and station history of an automatic weather station (AWS) on Denali Pass (5715 m MSL), Alaska. The station was installed by a team of climbers from the Japanese Alpine Club after a fatal accident involving Japanese climbers in 1989 and was operational intermittently between 1990 and 2007, measuring primarily air temperature and wind speed. In later years, the AWS was operated by the International Arctic Research Center of the University of Alaska Fairbanks. Station history is reconstructed from available documentation as archived by the expedition teams. To extract and preserve data records, the original datalogger files were processed. We highlight numerous challenges and sources of uncertainty resulting from the location of the station and the circumstances of its operation. The data records exemplify the harsh meteorological conditions at the site: air temperatures down to approximately −60°C were recorded, and wind speeds reached values in excess of 60 m s−1. Measured temperatures correlate strongly with reanalysis data at the 500-hPa level. An approximation of critical wind speed thresholds and a reanalysis-based reconstruction of the meteorological conditions during the 1989 accident confirm that the climbers faced extremely hazardous wind speeds and very low temperatures. The data from the Denali Pass AWS represent a unique historical record that can, we hope, serve as a basis for further monitoring efforts in the summit region of Denali.


Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 437
Author(s):  
Osías Ruiz-Alvarez ◽  
Vijay P. Singh ◽  
Juan Enciso-Medina ◽  
Ronald Ernesto Ontiveros-Capurata ◽  
Arturo Corrales-Suastegui

The objective of this research was to analyze the temporal patterns of monthly and annual precipitation at 36 weather stations of Aguascalientes, Mexico. The precipitation trend was determined by the Mann–Kendall method and the rate of change with the Theil–Sen estimator. In total, 468 time series were analyzed, 432 out of them were monthly, and 36 were annual. Out of the total monthly precipitation time series, 42 series showed a statistically significant trend (p ≤ 0.05), from which 8/34 showed a statistically significant negative/positive trend. The statistically significant negative trends of monthly precipitation occurred in January, April, October, and December. These trends denoted more significant irrigation water use, higher water extractions from the aquifers in autumn–winter, more significant drought occurrence, low forest productivity, higher wildfire risk, and greater frost risk. The statistically significant positive trends occurred in May, June, July, August, and September; to a certain extent, these would contribute to the hydrology, agriculture, and ecosystem but also could provoke problems due to water excess. In some months, the annual precipitation variability and El Niño-Southern Oscillation (ENSO) were statistically correlated, so it could be established that in Aguascalientes, this phenomenon is one of the causes of the yearly precipitation variation. Out of the total annual precipitation time series, only nine series were statistically significant positive; eight out of them originated by the augments of monthly precipitation. Thirteen weather stations showed statistically significant trends in the total precipitation of the growing season (May, June, July, August, and September); these stations are located in regions of irrigated agriculture. The precipitation decrease in dry months can be mitigated using shorter cycle varieties with lower water consumption, irrigation methods with high efficiency, and repairing irrigation infrastructure. The precipitation increase in humid months can be used to store water and use it during the dry season, and its adverse effects can be palliated with the use of varieties resistant to root diseases and lodging. The results of this work will be beneficial in the management of agriculture, hydrology, and water resources of Aguascalientes and in neighboring arid regions affected by climate change.


2021 ◽  
Author(s):  
Wenxuan Hu ◽  
Yvonne Scholz ◽  
Madhura Yeligeti ◽  
Lüder von Bremen ◽  
Marion Schroedter-Homscheidt

<p>Renewable energy sources such as wind energy play a crucial role in most climate change mitigation scenarios because of their ability to significantly reduce energy-related carbon emissions. In order to understand and design future energy systems, detailed modeling of renewable energy sources is important. In the light of making energy system modelling possible at all variability scales of local weather conditions, renewable energy source information with high resolution in both space and time are required.</p><p>Nowadays, renewable energy resources data that are widely used among the energy modeling community are reanalysis data such as ERA5, COSMO REA6, and MERRA2. Taking wind speed as an example, reanalysis data can provide long term spatially resolved wind information on any desired height in a physically consistent way. However, their spatial resolution is coarse. In order to obtain a fine spatial resolution data focusing on wind speed, this paper proposes a statistical downscaling method based on reanalysis data, observation data, and the local topography.</p><p>While most statistical wind downscaling studies have focused on obtaining site specific data or downscaling probability density functions, this paper focuses on downscaling one-year hourly wind speed time series for Europe to 0.00833 degree X 0.00833 degree (approximately 1km X 1km) resolution. It has been proven by various studies that the local topography influences wind speed. The topographic structure in this study is determined by two metrics: TPI, a topographic position index that compares the elevation of each cell to the mean elevation of the neighborhood areas and Sx, a slope-based, direction-dependent parameter that describes the topography in the upwind direction. The observation data used in this study are MeteoSwiss measurement values which provide the hourly wind speed time series at the station heights. For each weather station with observation data, biases described by the local terrain features are introduced to minimize the root mean square error (RMS) and Kolmogorov-Smirnov D (KSD) statistic between the corrected and the observed wind speed. These biases are then assigned to grid points with the same terrain types as the weather station, which enables downscaling of the wind speed for whole Europe.</p><p>The results show that this downscaling method can improve the RMS and KSD for both ERA5 and COSMO REA6, especially at mountain ridges, which indicates that it can not only decrease the bias, but also provide a better match to the observed wind speed distributions.</p>


Author(s):  
Fatkhuroyan Fatkhuroyan ◽  
Bambang Wijayanto

<p class="AbstractEnglish"><strong>Abstract:</strong> Wind has important role in aviation safety. The aim of the research is to analyze monthly wind profile and crosswind potential in the area of New Yogyakarta International Airport. The method used by installing 4 (four) AWS (Automatic Weather Station) at the end and the middle of the runway during March to September 2017. The results show that the wind patterns in the March-May period have varying directions with an average speed of 5-8 knots. In June - September, the wind pattern blows from the East - Southeast direction with an average speed of 6-9 knots. The maximum wind speed occurred between 14-20 knots and no crosswind potential was found for the runway length of 3,600 meters.</p><p class="AbstrakIndonesia"><strong>Abstrak:</strong> Angin merupakan unsur cuaca yang sangat penting dalam keselamatan penerbangan. Penelitian ini bertujuan melakukan analisa profil angin bulanan dan potensi terjadinya Crosswind pada area New Yogyakarta International Airport. Metode yang dipakai dengan memasang 4 (empat)buah AWS (Automatic Weather Station) di ujung dan tengah landasan selama bulan Maret hingga September 2017. Hasil pengamatan dan analisa menunjukan bahwa pola angin pada periode Maret – Mei memiliki arah yang bervariasi dengan kecepatan rata-rata 5 – 8 knot. Pada Juni – September, pola angin berhembus dari arah Timur – Tenggara dengan kecepatan rata-rata 6 – 9 knot. Selama periode pengamatan, kecepatan angin maksimum yang terjadi antara 14 – 20 knot dan tidak ditemukan potensi terjadinya cross wind untuk panjang landasan 3.600 meter.</p>


Author(s):  
Adrien Wehrlé ◽  
Jason E. Box ◽  
Masashi Niwano ◽  
Alexandre M. Anesio ◽  
Robert S. Fausto

The Programme for Monitoring of the Greenland Ice Sheet (PROMICE) provides surface meteorological and glaciological measurements from widespread on-ice automatic weather stations since mid-2007. In this study, we use 105 PROMICE ice-ablation time series to identify the timing of seasonal bare-ice onset preceded by snow cover conditions. From this collection, we find a bare-ice albedo at ice-ablation onset (here called bare-ice-onset albedo) of 0.565 ± 0.109 that has no apparent spatial dependence among 20 sites across Greenland. We then apply this snow-to-ice albedo transition value to measure the variations in daily Greenland bare-ice area in Sentinel-3 optical satellite imagery covering the extremely low and high respective melt years of 2018 and 2019. Daily Greenland bare-ice area peaked at 153 489 km² in 2019, 1.9 times larger than in 2018 (80 220 km²), equating to 9.0% (in 2019) and 4.7% (in 2018) of the ice sheet area.


2013 ◽  
Vol 30 (4) ◽  
pp. 709-724 ◽  
Author(s):  
Matthew Hobby ◽  
Matthew Gascoyne ◽  
John H. Marsham ◽  
Mark Bart ◽  
Christopher Allen ◽  
...  

Abstract The Fennec automatic weather station (AWS) network consists of eight stations installed across the Sahara, with four in remote locations in the central desert, where no previous meteorological observations have existed. The AWS measures temperature, humidity, pressure, wind speed, wind direction, shortwave and longwave radiation (upwelling and downwelling), ground heat flux, and ground temperature. Data are recorded every 3 min 20 s, that is, at 3 times the temporal resolution of the World Meteorological Organization’s standard 10-min reporting for winds and wind gusts. Variations in wind speeds on shorter time scales are recorded through the use of second- and third-order moments of 1-Hz data. Using the Iridium Router-Based Unrestricted Digital Internetworking Connectivity Solutions (RUDICS) service, data are transmitted in near–real time (1-h lag) to the United Kingdom, where calibrations are applied and data are uploaded to the Global Telecommunications System (GTS), for assimilation into forecast models. This paper describes the instrumentation used and the data available from the network. Particular focus is given to the engineering applied to the task of making measurements in this remote region and challenging climate. The communications protocol developed to operate over the Iridium RUDICS satellite service is described. Transmitting the second moment of the wind speed distribution is shown to improve estimates of the dust-generating potential of observed winds, especially for winds close to the threshold speed for dust emission of the wind speed distribution. Sources of error are discussed and some preliminary results are presented, demonstrating the system’s potential to record key features of this region.


Irriga ◽  
2006 ◽  
Vol 11 (2) ◽  
pp. 139-149 ◽  
Author(s):  
André Luiz Teixeira Fernandes ◽  
Marcos Vinícius Folegatti ◽  
Antonio Roberto Pereira

AVALIAÇÃO DE DIFERENTES MÉTODOS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DA CULTURA DO CRISÂNTEMO (Chrisantemum spp.) CULTIVADO EM ESTUFA PLÁSTICA  André Luiz Teixeira Fernandes1; Marcos Vinícius Folegatti2; Antonio Roberto Pereira21Pró Reitoria de Pesquisa e Pós Graduação, Universidade de Uberaba, Uberaba, MG, andré[email protected] de Engenharia Rural, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP  1 RESUMO  Com o objetivo de estudar métodos de controle de irrigação numa cultura de crisântemo, instalou-se uma estação agrometeorológica automática, numa estufa de 5600 m2, com  sensores de temperatura do ar, velocidade do vento, umidade relativa do ar, radiação solar global e lisímetro de pesagem com célula de carga, conectados a um coletor de dados. A partir dos dados meteorológicos obtidos, estimou-se a evapotranspiração da cultura utilizando-se os seguintes métodos: Tanque evaporimétrico, Camargo, Makkink, Radiação solar, Jensen-Haise, Linacre, Hargreaves-Samani, Penman, Penman-piche e Penman-Monteith. Os resultados foram comparados com as medições do lisímetro, considerado padrão. Os métodos que obtiveram maiores índices de correlação foram: Jensen-Haise (72,50%); Radiação Solar (71,53%); Makkink (71,53%), Penman-Monteith (71,16%) e Penman (72,09%).UNITERMOS: evapotranspiração, comparação entre métodos, cultura do crisântemo, cultivo protegido.  FERNANDES, A. L. T.; FOLEGATTI, M. V.; PEREIRA, A. R. VALUATION OF DIFFERENT EVAPOTRANSPIRATION ESTIMATE METHODS FOR (Chrysanthemum spp) CULTIVATED IN PLASTIC GREENHOUSE  2 ABSTRACT In order to study some methods to control irrigation of a chrysanthemum crop, an automatic weather station was installed inside a 5600 m2 greenhouse with the following sensors connected to a data logger: air temperature, relative humidity, wind speed, solar radiation and a weighing lysimeter. Evapotranspiration (ET) was estimated by the weather station data using the following methods: Solar Radiation, Pan Evaporation, Camargo, Makkink, Jensen-Haise, Linacre, Hargreaves-Samani, Penman, Penman-piche and Penman-Monteith. The results were compared with the ones from the weighing lysimeter data, which were considered standard. The best correlation indices were obtained by: Jensen-Haise (72.50%); solar radiation (71.53%); Makkink (71.53%), Penman-Monteith (71.16%) and Penman (72.09%). KEYWORDS: evapotranspiration, comparison of methods, chrysanthemum crop, protecting culture 


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