Influence of Meteorological Factors on the Potential Evapotranspiration in Yanhe River Basin, China

Potential evapotranspiration (ET0) is an essential component of the hydrological cycle, and quantitative estimation of the influence of meteorological factors on ET0 can provide a scientific basis for studying the impact mechanisms of climate change. In the present research, the Penman–Monteith method was used to calculate ET0. The Mann–Kendall statistical test with the inverse distance weighting were used to analyze the spatiotemporal characteristics of the sensitivity coefficients and contribution rates of meteorological factors to ET0 to identify the mechanisms underlying changing ET0 rates. The results showed that the average ET0 for the Yanhe River Basin, China from 1978–2017 was 935.92 mm. Save for a single location (Ganquan), ET0 increased over the study period. Generally, the sensitivity coefficients of air temperature (0.08), wind speed at 2 m (0.19), and solar radiation (0.42) were positive, while that of relative humidity was negative (−0.41), although significant spatiotemporal differences were observed. Increasing air temperature and solar radiation contributed 1.09% and 0.55% of the observed rising ET0 rates, respectively; whereas decreasing wind speed contributed −0.63%, and relative humidity accounted for −0.85%. Therefore, it was concluded that the decrease of relative humidity did not cause the observed ET0 increase in the basin. The predominant factor driving increasing ET0 was rising air temperatures, but this too varied significantly by location and time (intra- and interannually). Decreasing wind speed at Ganquan Station decreased ET0 by −9.16%, and was the primary factor underlying the observed, local “evaporation paradox”. Generally, increase in ET0 was driven by air temperature, wind speed and solar radiation, whereas decrease was derived from relative humidity.

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Influence of Meteorological Factors on the Potential Evapotranspiration in Yanhe River Basin, China

10.22541/au.161606525.58625543/v1 ◽

2021 ◽

Author(s):

yu luo ◽

Peng Gao ◽

Xingmin Mu

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Solar Radiation ◽

River Basin ◽

Air Temperature ◽

Hydrological Cycle ◽

Meteorological Factors ◽

Potential Evapotranspiration ◽

Sensitivity Coefficients ◽

The Impact

Potential evapotranspiration (ET) is an essential component of the hydrological cycle, and quantitative estimation of the influence of meteorological factors on ET can provide a scientific basis for studying the impact mechanisms of climate change. In the present research, the Penman-Monteith method was used to calculate ET. The Mann-Kendall statistical test with the inverse distance weighting were used to analyze the spatiotemporal characteristics of the sensitivity coefficients and contribution rates of meteorological factors to ET to identify the mechanisms underlying changing ET rates. The results showed that the average ET for the Yanhe River Basin, China from 1978–2017 was 935.92 mm. Save for a single location (Ganquan), ET increased over the study period. Generally, the sensitivity coefficients of air temperature (0.08), wind speed at 2 m (0.19), and solar radiation (0.42) were positive, while that of relative humidity was negative (-0.41), although significant spatiotemporal differences were observed. Increasing air temperature and solar radiation contributed 1.09% and 0.55% of the observed rising ET rates, respectively; whereas decreasing wind speed contributed -0.63%, and relative humidity accounted for -0.85%. Therefore, it was concluded that the decrease of relative humidity did not cause the observed ET increase in the basin. The predominant factor driving increasing ET was rising air temperatures, but this too varied significantly by location and time (intra- and interannually). Decreasing wind speed at Ganquan Station decreased ET by -9.16%, and was the primary factor underlying the observed, local “evaporation paradox.” Generally, increases in ET were driven by air temperature, wind speed and solar radiation, whereas decreases were derived from relative humidity.

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Estimation of the Influence of Meteorological Factors on the Potential Evapotranspiration of Yanhe River Basin

10.22541/au.161123412.25069249/v1 ◽

2021 ◽

Author(s):

yu luo ◽

Peng Gao ◽

Xingmin Mu ◽

dexun Qiu

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Solar Radiation ◽

River Basin ◽

Air Temperature ◽

Meteorological Factors ◽

Sensitivity Coefficient ◽

Downward Trend ◽

Upward Trend ◽

Temporal And Spatial

Potential evapotranspiration (ET) is an important expenditure item in the hydrological cycle. Quantitative estimation of the influence of meteorological factors on ET can provide a scientific basis for the study of the impact mechanism of climate change on the hydrological cycle. In this paper, the Penman-Monteith method was used to calculate ET. The Mann-Kendall statistical test and the Inverse Distance Weighting method were used to analyze the temporal and spatial characteristics of the sensitivity coefficient of ET to meteorological factors and contribution rate of meteorological factors to ET. And the reasons for the change of ET were quantitatively explored in combination with the change trend of meteorological factors. The results showed that the average ET in the Yanhe River Basin from 1978 to 2017 was 935.92mm. Except for Ganquan Station, ET showed an upward trend. Generally, the sensitivity coefficient of air temperature (0.08), wind speed (0.19) and solar radiation (0.42) was positive and the sensitivity coefficient of relative humidity (-0.41) was negative. But there were significant temporal and spatial differences. The upward trend of air temperature and solar radiation contributed 1.09% and 0.55% to ET. Respectively, the downward trend of wind speed contributed -0.63% And the downward trend of relative humidity contributed to -0.85% of ET. Therefore, the decrease of relative humidity did not cause the increase of ET in Yanhe River basin. The dominant factor of the upward trend of ET was air temperature. But the dominant factors of ET had significant temporal and spatial differences. The downward trend of wind speed at Ganquan Station contributed -9.16% to ET, which indicated the dominant factor of “evaporation paradox” in Ganquan area was wind speed. Generally, the increase of ET was related to air temperature, wind speed and solar radiation. And the decrease of ET was related to relative humidity.

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Spatiotemporal Variability of Potential Evaporation in Heihe River Basin Influenced by Irrigation

10.5194/egusphere-egu2020-12520 ◽

2020 ◽

Author(s):

Congying Han

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Spatial Pattern ◽

River Basin ◽

Meteorological Factors ◽

Heihe River Basin ◽

Spatiotemporal Variability ◽

Maximum Temperature ◽

Heihe River ◽

Potential Evaporation

Spatiotemporal Variability of Potential Evaporation in Heihe River Basin Influenced by Irrigation Congying Han1,2, Baozhong Zhang1,2, Songjun Han1,21 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.2 National Center of Efficient Irrigation Engineering and Technology Research-Beijing, Beijing 100048, China.Corresponding author: Baozhong Zhang ([email protected])Abstract: Potential evaporation is a key factor in crop water requirement estimation and agricultural water resource planning. The spatial pattern and temporal changes of potential evaporation calculated by Penman equation (EPen) (1970-2017) in Heihe River Basin (HRB), Northwest China were evaluated by using data from 10 meteorological stations, with a serious consideration of the influences of irrigation development. Results indicated that the spatial pattern of annual EPen in HRB was significantly different, among which the EPen of agricultural sites (average between 1154 mm and 1333 mm) was significantly higher than that of natural sites (average between 794 mm and 899 mm). Besides, the coefficient of spatial variation of the aerodynamic term (Eaero) was 0.4, while that of the radiation term (Erad) was 0.09. The agricultural irrigation water withdrawal increased annually before 2000, but decreased significantly after 2000 which was influenced by the agricultural development and the water policy. Coincidentally, the annual variation of Epen in agricultural sites decreased at -40 mm/decade in 1970-2000 but increased at 60 mm/decade in 2001-2017, while that in natural sites with little influence of irrigation, only decreased at -0.5mm/decade in 1970-2000 but increased at 11 mm/decade in 2001-2017. So it was obvious that irrigation influenced Epen significantly and the change of Epen was mainly caused by the aerodynamic term. The analysis of the main meteorological factors that affect Epen showed that wind speed had the greatest impact on Epen of agricultural sites, followed by relative humidity and average temperature, while the meteorological factors that had the greatest impact on Epen of natural sites were maximum temperature, followed by wind speed and relative humidity.

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Investigation on the Temperature Distribution of Asphalt Overlay on the Existing Cement Concrete Pavement in Hot-Humid Climate in Southern China

Advances in Civil Engineering ◽

10.1155/2021/2984650 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Zuzhong Li ◽

Yayun Zhang ◽

Chunguang Fa ◽

Xiaoming Zou ◽

Haiwei Xie ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Solar Radiation ◽

Prediction Model ◽

Air Temperature ◽

Concrete Pavement ◽

Humid Climate ◽

Temperature Prediction ◽

Asphalt Overlay ◽

Hot Humid Climate

Temperature is known to be one of the most important factors affecting the design and performance of asphalt concrete pavement. The distresses of asphalt overlay are closely related to its temperature, particularly in Guangxi, a hot-humid-climate region in China. This research is to analyze the impact of meteorological factors on temperature at 2 cm depth in asphalt overlay by ReliefF algorithm and also obtain the temperature prediction model using MATLAB. Two test sites were installed to monitor the temperatures at different pavement depths from 2014 to 2016; meanwhile, the meteorological data (including air temperature, solar radiation, wind speed, and relative humidity) were collected from the two meteorological stations. It has been found that the temperature at 2 cm depth experiences greater temperature variation, and the maximum and minimum temperatures of asphalt overlay, respectively, occur at 2 cm depth and on the surface. Besides, the results of ReliefF algorithm have also shown that the temperature at 2 cm depth is affected significantly by solar radiation, air temperature, wind speed, and the relative humidity. Based on these analyses, the prediction model of maximum temperature at 2 cm depth is developed using statistical regression. Moreover, the data collected in 2017 are used to validate the accuracy of the model. Compared with the existing models, the developed model was confirmed to be more effective for temperature prediction in hot-humid region. In addition, the analysis of rutting depth and overlay deformation for the two test sections with different materials is done, and the results have shown that reasonable structure and materials of asphalt overlay are vital to promote the high-temperature antideforming capability of pavement.

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Ranking Potential Evapotranspiration Models in the Prediction of Maize Water Requirements in the PortHarcourt Area of Nigeria

Outlook on Agriculture ◽

10.5367/000000003101294262 ◽

2003 ◽

Vol 32 (1) ◽

pp. 51-56 ◽

Cited By ~ 1

Author(s):

M.J. Ayotamuno

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Meteorological Factors ◽

Potential Evapotranspiration ◽

Empirical Models ◽

Geographical Region ◽

Net Radiation ◽

Temperature Elevation ◽

Water Requirements

It has been observed that many of the empirical models used to estimate evapotranspiration, although simple, are not sufficiently sensitive in those areas where the temperature is relatively constant but other meteorological factors that promote evapotranspiration vary (Michael, 1978; Hashemi and Haliban, 1979). It is therefore important to verify, or even recalibrate these models when they are used within a new geographical region or climatic area (eg PortHarcourt, Nigeria) if account is to be taken of relational changes between meteorological factors such as net radiation, air temperature, elevation, advection and relative humidity.

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Efectos de las condiciones ambientales sobre el comportamiento ingestivo en bovinos de carne en un sistema intensivo en el Valle del Sinú

Ciencia y Tecnología Agropecuaria ◽

10.21930/rcta.vol13_num2_art:257 ◽

2013 ◽

Vol 13 (2) ◽

pp. 207 ◽

Cited By ~ 2

Author(s):

Emiro Suárez P. ◽

Sony Reza G. ◽

Eliecer Díaz A. ◽

Fredy García C. ◽

Iván Pastrana V. ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Solar Radiation ◽

Beef Cattle ◽

Air Temperature ◽

Ingestive Behavior ◽

Average Weight ◽

Zebu Cattle ◽

Panicum Maximum ◽

Atmospheric Variables

Incrementos en la temperatura ambiental y la humedad relativa, unidas al efecto de la radiación solar, ocasionan pérdidas en el bienestar animal, afectando la conducta ingestiva y la productividad animal. Por ello el objetivo de este estudio fue analizar las relaciones entre las variables atmosféricas, como temperatura del aire, humedad relativa, velocidad del viento y radiación solar, con los tiempos de pastoreo y de rumia de bovinos cebú comercial. La investigación se llevó a cabo durante 96 días, entre julio-octubre de 2010, en el C.I. Turipaná de Corpoica (Cereté, Colombia). Bovinos machos enteros (27), con peso promedio 314 ± 29 kg, pastorearon en un área de 18 hectáreas, establecidas en Panicum maximum cv. Mombasa, Cynodonnlem fluensis y Brachiaria híbrido cv. Mulato II, sin disponibilidad de sombra. Se realizaron ocho evaluaciones durante 8 días dentro del periodo experimental de las variables atmosféricas e ingestivas y las anotaciones se hicieron en un lapso de 12 horas continuas (6:00 AM a 6:00 PM). Los resultados resaltan que al aumentar la temperatura del aire, humedad relativa y la radiación solar, disminuyó el tiempo de pastoreo y aumentó el tiempo de rumia, mientras que al aumentar la velocidad del viento se incrementó el tiempo de pastoreo y disminuyó el tiempo de rumia. Los resultados obtenidos indicaron que la temperatura del aire, humedad relativa, radiación solar y velocidad del viento, presentaron una influencia directa sobre el comportamiento ingestivo de los bovinos de carne manejados en sistemas intensivos (sin sombra) en el Valle del Sinú. Effects of environmental conditions on feeding behavior in beef cattle in an intensive system in the Sinú Valley Increases in temperature and relative humidity together with the solar radiation effect are detrimental to animal welfare, affecting their behavior when it comes to feeding and digestive behavior, which affects their productivity. Therefore, the goal of this research was to analyze the link between atmospheric variables, air temperature, relative humidity, wind speed and solar radiation to the time of grazing and rumination of commercial Zebu cattle. The research took place from July to October 2010, at the Turipaná Center, Corpoica (Cereté, Colombia). Male intact bovines (27), with an average weight of 314 ± 29 kg, grazed in an area of 18 hectares, established with Panicum maximum cv. Mombasa, Cynodonnlem fluensis and Brachiaria hybrid cv. Mulato II, without shade availability. Eight evaluations were conducted for 8 days in the experimental period for atmospheric variables and ingestion. Notes were taken in 12 hour time frames (6:00 AM a 6:00 PM). The outcome showed that as the air temperature, relative humidity and solar radiation increased, the grazing time decreased and rumination time lasted longer. However, when wind speed increased, grazing time increased as well and rumination took less time. The results showed that the air temperature, relative humidity, solar radiation and wind speed had a direct influence on the ingestive behavior of beef cattle managed in intensive systems (shadeless) in Valle del Sinú.

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Mugwort (Artemisia L.) pollen in aeroplankton of Lublin, 2001-2005

Acta Agrobotanica ◽

10.5586/aa.2006.067 ◽

2012 ◽

Vol 59 (2) ◽

pp. 121-130

Author(s):

Elżbieta Weryszko-Chmielewska ◽

Bogusław M. Kaszewski ◽

Krystyna Piotrowska

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Negative Correlation ◽

Pollen Season ◽

Significant Positive Correlation ◽

Meteorological Factors ◽

Pollen Grains ◽

Volumetric Method ◽

Pollen Concentration ◽

The Impact

The course of the Artemisia pollen season was recorded in Lublin over a period of five years: 2001-2005. The volumetric method was applied in the studies, using a VPPS 2000 Lanzoni trap. The length of the season was determined by the 98% method. The impact of several meteorological factors on the start and course of the pollen season was analysed. It was found that in the five-year period studied the mugwort pollen season started in the second or third decade of July and lasted 59-90 days. Maximum concentrations in the range of 103-221 pollen grains in 1 m3 of air were noted between 2 and 9 August. Annual totals of mugwort pollen grains ranged from 1496 to 2532. A significant positive correlation was demonstrated between the Artemisia pollen concentration and air temperature, and a negative correlation between the pollen concentration and air relative humidity and cloudiness. A significant impact of temperature on the start of the Artemisia pollen season was also found.

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Examine the impact of weather and ambient air pollutant parameters on daily case of COVID-19 in India

10.1101/2020.06.08.20125401 ◽

2020 ◽

Author(s):

Kousik Das ◽

Nilanjana Das Chatterjee

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Solar Radiation ◽

Ambient Air ◽

List Type ◽

Positive Relation ◽

Weather Variables ◽

Sensitive Analysis ◽

Negative Relation ◽

The Impact

AbstractThe present study presents a view on exploring the relationship pattern between COVID 19 daily cases with weather parameters and air pollutants in mainland India. We consider mean temperature, relative humidity, solar radiation, rainfall, wind speed, PM2.5, PM10, SO2, NO2 and CO as independent variable and daily COVID 19 cases as dependent variable for 18 states during 18th march to 30th April, 2020.After dividing the dataset for 0 to 10 day, 10 to 25 days and 0 to 44 days, the current study applied Akaike s Information Criteria (AIC) and Generalized Additive Model (GAM) to examine the kind of relationship between independent variables with COVID 19 cases. Initially GAM model result shows variables like temperature and solar radiation has positive relation (p<0.05) in 0 to 10 days study with daily cases. In 25 days dataset it significantly shows that temperature has positive relation above 23 degree centigrade, SO2 has a negative relationship and relative humidity has negative (between 30% to 45% and > 60%) and a positive relationship (45% to 60%) with COVID 19 cases (p=0.05). 44 days dataset has six parameters includes temperature as positive, relative humidity as negative (between 0 to 45%) and then positive (after >45%), NO2 as Positive (0 to 35 microgram/m3) followed by negative trend (after > 40 microgram/m3), SO2 and rainfall as negative relation. After sensitive analysis, it is found that weather variables like relative humidity, solar radiation and rainfall are more sensitive than temperature and wind speed. Whereas pollutants like NO2, PM2.5, PM10 and CO are more sensitive variables than SO2 in this study. In summary this study finds temperature, relative humidity, solar radiation, wind speed, SO2, PM2.5, and CO may be important factors associated with COVID 19 pandemic.Graphical AbstractHighlights➢There was a significant relationship between daily positive COVID-19 case with weather and pollution factors➢We found PM2.5 and CO positively associated with transmission of positive cases where as NO2 and SO2 have a negative relation after sensitive analysis.➢We have found temperature and wind speed have positive relation whereas, relative humidity and solar radiation have negative relation after sensitive analysis.➢Weather variables like relative humidity and solar radiation and rainfall are more sensitive than temperature and wind speed. Pollutants like NO2, PM2.5, PM10 and CO are more sensitive variables than SO2 in this study.

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Exploring the Driving Factors of the Spatiotemporal Variation of Precipitation in the Jing–Jin–Ji Urban Agglomeration from 2000 to 2015

Sustainability ◽

10.3390/su12187426 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7426

Author(s):

Feili Wei ◽

Ze Liang ◽

Yueyao Wang ◽

Zhibin Huang ◽

Huan Wang ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Meteorological Factors ◽

Urban Climate ◽

Explanatory Power ◽

Interaction Factors ◽

Impact Of Urbanization ◽

Precipitation Changes ◽

Annual Scale ◽

The Impact

Urbanization has a significant impact on urban precipitation. Existing studies on precipitation pay more attention to the impact of natural and meteorological factors, and the research on the impact of urbanization on the spatial patterns of precipitation is still very deficient. Based on geographic detection, this study quantitatively analyzed the dominant, interaction, and sensitivity factors that affect precipitation changes in more than 150 urban units in Jing–Jin–Ji (Beijing–Tianjin–Hebei) during the process of urbanization. The research findings show the following: ① The dominant factors have seasonal differences in terms of the precipitation variation in Jing–Jin–Ji. The leading factors in summer were the change of radiation and relative humidity. The dominant factors in winter were the changes in radiation, relative humidity, and wind speed. On the annual scale, the dominant factors were the changes in relative humidity, aerosol optical depth, radiation, and wind speed. ② Whether in summer, in winter, or on the annual scale, urbanization can enhance the explanatory power of spatial variation of urban precipitation through interaction with natural/meteorological factors, and all the dominant interaction factors show a nonlinear enhancement trend. ③ The night light intensity and urban heat island can greatly amplify the explanatory power of other factors, thus becoming the most sensitive factor in urbanization precipitation changes. The above research can provide a theoretical basis for the formulation of urban climate policies and urban planning.

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Effect of meteorological factors on photovoltaic power forecast based on the neural network

RSC Advances ◽

10.1039/c7ra10591f ◽

2017 ◽

Vol 7 (88) ◽

pp. 55846-55850 ◽

Cited By ~ 5

Author(s):

Wenbo Xiao ◽

Jin Dai ◽

Huaming Wu ◽

Gina Nazario ◽

Feng Cheng

Keyword(s):

Neural Network ◽

Wind Speed ◽

Relative Humidity ◽

Air Temperature ◽

Meteorological Factors ◽

Network Models ◽

Neural Network Models ◽

Photovoltaic Power ◽

The Neural Network

In this paper, the effects of meteorological factors (including air temperature, wind speed, and relative humidity) on photovoltaic (PV) power forecast using neural network models have been studied.

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