Upper air meteorological elements and rainfall over Salem

Author(s):  
Rajasri Sen Jaiswal ◽  
Thirumala L. K ◽  
Mukundan M ◽  
Siva M ◽  
Neela V. S. ◽  
...  
2012 ◽  
Vol 4 (4) ◽  
pp. 296
Author(s):  
Qin Jia ◽  
Ding Yong-Jian ◽  
Ye Bai-Sheng ◽  
Wang Sheng-Xia ◽  
Gao Ming-Jie ◽  
...  

2021 ◽  
Vol 13 (7) ◽  
pp. 1267
Author(s):  
Honglei Wang ◽  
Ankang Liu ◽  
Zhongxiu Zhen ◽  
Yan Yin ◽  
Bin Li ◽  
...  

As the largest independent east–west-trending mountain in the world, Mt. Tianshan exerts crucial impacts on climate and pollutant distributions in central Asia. Here, the vertical structures of meteorological elements and black carbon (BC) were first derived at Mt. Tianshan using an unmanned aerial vehicle system (UAVS). Vertical changes in meteorological elements can directly affect the structure of the planet boundary layer (PBL). As such, the influences of topography and meteorological elements’ vertical structure on aerosol distributions were explored from observations and model simulations. The mass concentrations of BC changed slightly with the increasing height below 2300 m above sea level (a.s.l.), which significantly increased with the height between 2300–3500 m a.s.l. and contrarily decreased with ascending altitude higher than 3500 m. Topography and mountain–valley winds were found to play important roles in the distributions of aerosols and BC. The prevailing valley winds in the daytime were conducive to pollutant transport from surrounding cities to Mt. Tianshan, where the aerosol number concentration and BC mass concentration increased rapidly, whereas the opposite transport pattern dominated during nighttime.


Author(s):  
Zhujun Dai ◽  
Duanyang Liu ◽  
Kun Yu ◽  
Lu Cao ◽  
Youshan Jiang

Steady meteorological conditions are important external factors affecting air pollution. In order to analyze how adverse meteorological variables affect air pollution, surface synoptic situation patterns and meteorological conditions during heavy pollution episodes are discussed. The results showed that there were 78 RPHPDs (regional PM2.5 pollution days) in Jiangsu, with a decreasing trend year by year. Winter had the most stable meteorological conditions, thus most RPHPDs appeared in winter, followed by autumn and summer, with the least days in spring. RPHPDs were classified into three patterns, respectively, as equalized pressure (EQP), advancing edge of a cold front (ACF) and inverted trough of low pressure (INT) according to the SLP (sea level pressure). RPHPDs under EQP were the most (51%), followed by ACF (37%); INT was the minimum (12%). Using statistical methods and meteorological condition data on RPHPDs from 2013 to 2017 to deduce the thresholds and 2018 as an independent dataset to validate the proposed thresholds, the threshold values of meteorological elements are summarized as follows. The probability of RPHPDs without rain was above 92% with the daily and hourly precipitation of all RPHPDs below 2.1 mm and 0.8 mm. Wind speed, RHs, inversion intensity(ITI), height difference in the temperature inversion(ITK), the lower height of temperature inversion (LHTI) and mixed-layer height (MLH) in terms of 25%–75% high probability range were respectively within 0.5–3.6 m s−1, 55%–92%, 0.7–4.0 °C 100 m −1, 42–576 m, 3–570 m, 200–1200 m. Two conditions should be considered: whether the pattern was EQP, ACF or INT and whether the eight meteorological elements are within the thresholds. If both criteria are met, PM2.5 particles tend to accumulate and air pollution diffusion conditions are poor. Unfavorable meteorological conditions are the necessary, but not sufficient condition for RPHPDs.


2017 ◽  
Vol 39 (2) ◽  
Author(s):  
LUCAS EDUARDO DE OLIVEIRA APARECIDO ◽  
RAFAEL BIBIANO FERREIRA ◽  
GLAUCO DE SOUZA ROLIM ◽  
BIANCA SARZI DE SOUZA ◽  
PAULO SERGIO DE SOUZA

ABSTRACT The influence of climate on the development of lychee fruit is complex, but few studies have discussed the problem. We developed agrometeorological models for simulating the development of fruit fresh matter (FM), fruit dry matter (DM), fruit length (LE), fruit diameter (DI), fruit volume (VO), and fruit number per cluster (FN) of the “Bengal” lychee cultivar as functions of climatic conditions. We conducted three analyses: (a) the influence of mean meteorological elements on the rates of fruit growth, (b) estimation of fruit development by the agrometeorological models using sigmoidal adjustments, and (c) simulation of fruit development using multiple nonlinear regression of two meteorological elements to improve the accuracy. A rate of water deficit (WD) near 5 mm d-1 maximised FM, DM, LE, DI, and VO. Increases in potential evapotranspiration (PET), degree days (DD), and actual evapotranspiration (AET) were correlated with increases in VO and decreases in LE and NF. Models estimating fruit development indicated that the accumulation of WD, PET, AET, and DD had sigmoidal relationships with all variables of fruit growth except FN. FN decreased as WD, PET, AET, and DD increased. The adjusted multivariate models were accurate, with the largest error of 6.45 cm3 (VO). The best models were: FM = f(SWD, DD), LE = f(SAET, DD), DI = f(SWD, DD), VO = f(SWD, DD), and FN = f(SAET, WD).


Author(s):  
Iug Lopes ◽  
Marcos V. da Silva ◽  
Juliana M. M. de Melo ◽  
Abelardo A. de A. Montenegro ◽  
Héliton Pandorfi

ABSTRACT Spatial variability analysis of meteorological elements and precise identification of possible causes of thermal stress in poultry housing help producers in the decision making process. The objective of this study was to evaluate the internal environment of poultry houses in the downtime (sanitary void) and in the production phase, to characterize spatial thermal variability and to identify critical control points. The study was carried out in the Alluvial Valley of the Mimoso River, municipality of Pesqueira, PE, Brazil. The data of air temperature, wind speed and illuminance were recorded in November (spring season), at 155 points within each poultry facility (10 x 90 m), spaced in a 3.0 x 2.5 m grid and subjected to descriptive statistical analysis and geostatistics. There was a strong spatial dependence for the variables air temperature, wind speed and illuminance. The ranges obtained for the air temperature in the facilities were from 48.22 to 114.52 m, while for the wind speed and illuminance were less than 10 m, thus revealing the need for greater homogeneity of the studied variables and meeting of the thermal requirement of the poultry.


Irriga ◽  
2002 ◽  
Vol 7 (3) ◽  
pp. 176-184
Author(s):  
Cláudio Marcio Pereira de Souza ◽  
Antonio Evaldo Klar ◽  
Luiza Helena Duenhas

EVALUATION OF METEOROLOGICAL ELEMENTS AND LETTUCE (Lactuca sativa, L.) YIELD RELATED TO GEOGRAPHIC ORIENTATION OF POLYETHYLENE GREENHOUSES   Cláudio Márcio Pereira de SouzaAntonio Evaldo Klar*Department of Agricultural Engineering, College of Agricultural Sciences, State University of São Paulo, P.O. 237, CEP 18603-970, Botucatu – SP. E-mail: [email protected]* Scientific Researcher of CNPqLuiza Helena DuenhasEMBRAPA Semi Árido, P.O. 23, CEP 56300–970, Petrolina – PE.   1 ABSTRACT  This experiment was carried out at the Agricultural Engineering Department, FCA/UNESP, Botucatu–SP aiming to study  the geographic orientation influence of two plastic tunnels (East/West and North/South based on the magnetic North) on lettuce plant (Lactuca sativa L, cv. Elisa) behavior and on the evaporation distribution uniformity inside the tunnels. The plants were sowed on 05/05/1999, transplanted on 05/29/1999 and harvested on 06/31/1999. Tensiometers were used to monitore soil water potentials. A drip irrigation system was used. Both tunnels received A Class pan and thermohygrographes in the center and 3 m apart small evaporimeters set at 3 heights (0.50 m, 1.00 m and 1.50 m). Through geostatistical analysis, there was not neither spatial dependency nor spatial variability of evaporation in both tunnels. However, the height of evaporimeters showed statistical differences: the 1.50 m height evaporimeter had slower evaporation than those from other heights. The air temperature, relative humidity and vapor pressure deficit averages were not statistically significant in both greenhouses when they were compared to those from the outside. A Class pan evaporation values were higher outside the tunnels than inside them, but there were no differences between both tunnels for this variable. The lettuce plant yield was not influenced by tunnel orientation, but there were significant differences on plant yield among beds inside each tunnel.  Keywords: evaporation, irrigation, greenhouse.   SOUZA, C. M. P., KLAR, A. E., DUENHAS, L. H. AVALIAÇÃO DE ELEMENTOS METEOROLÓGICOS E PRODUÇÃO DE ALFACE (Lactuca sativa L.) AFETADOS PELA ORIENTAÇÃO GEOGRÁFICA DE ESTUFAS DE POLIETILENO.   2 RESUMO  O experimento foi realizado na área experimental do Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas – Unesp/Botucatu, Estado de São Paulo, em duas estufas dispostas em diferentes orientações geográficas, Leste/Oeste e Norte/Sul. A alface (Lactuva sativa L.) cv. Elisa foi cultivada em ambas estufas, sendo semeada em 05/05/99, transplantada em 29/05/99 e colhida em 31/06/99. Utilizou-se tensiômetros para monitorar o potencial de água no solo para realizar o manejo do sistema de irrigação por gotejamento. Microevaporímetros eqüidistantes de 3 m e colocados em 3 alturas, 0.50, 1.00 e 1.50 m, termohigrógrafos e tanques Classe “A” foram instalados nas duas estufas. Através de análise geoestatística, não se observou dependência espacial nem variabilidade espacial da evaporação nas duas estufas. Entretanto, a altura dos evaporímetros apresentou diferenças significativas: a evaporação à altura de 1.50 foi menor que nas outras duas.As médias de temperatura, umidade relativa e déficit de pressão de vapor do arnão diferiram estatisticamente entre as estufas e o ambiente externo. Os valores médios de evaporação de água no tanque Classe “A” instalado fora das estufas diferiram estatisticamente quando comparados com os instalados no interior das estufas, porém, entre as orientações não se constatou diferença significativa. Pôde-se verificar que não houve diferença significativa das características agronômicas da alface em ambas orientações estudadas. No entanto, houve diferença significativa para essas características entre os canteiros no interior das mesmas, havendo variância espacial para os dados de matéria fresca apenas na estufa N/S.  UNITERMOS: evaporação, irrigação, estufa.


2018 ◽  
Vol 34 (4) ◽  
pp. 283-293 ◽  
Author(s):  
Myoung Nam Kim ◽  
Bo A Lim ◽  
Jin Young Hong ◽  
Jeung Min Lee ◽  
Ji Hee Park ◽  
...  

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