scholarly journals Color Portion of Solar Radiation in the Partial Annular Solar Eclipse, October 3rd, 2005, at Helwan, Egypt

10.14311/1287 ◽  
2010 ◽  
Vol 50 (6) ◽  
Author(s):  
A. H. Hassan ◽  
U. A. Rahoma ◽  
M. Sabry ◽  
A. M. Fathy
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Optical Depth ◽  
Air Temperature ◽  
Solar Eclipse ◽  
Diffuse Radiation ◽  
Maximum Magnitude ◽  
Radiation Level ◽  
First Contact ◽  
Annular Solar Eclipse

Measurements were made of various solar radiation components, global, direct and diffuse and their fractions during the partial annular solar eclipse on October 3rd, 2005 at Helwan, Egypt (Lat. 29.866◦ N and Long. 31.20◦ E), and an analysis has been made. The duration of the solar eclipse was 3 h 17 min, and the maximum magnitude of the eclipse in this region was 0.65. The optical depth of the direct component and the relative humidity decreased, while both the transparency and the air temperature increased towards the maximum eclipse. The general trends of the global components are decreasing optical depth and increasing transparency between the first contact and the last contact. The prevailing color during the eclipse duration was diffused infrared (77 % of the total diffuse radiation level).

scholarly journals Detrended Multiple Cross-Correlation Coefficient applied to solar radiation, air temperature and relative humidity

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Andrea de Almeida Brito ◽  
Heráclio Alves de Araújo ◽  
Gilney Figueira Zebende
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Solar Energy ◽  
Correlation Coefficient ◽  
Air Temperature ◽  
Cross Correlation ◽  
Global Solar Radiation ◽  
Meteorological Variables ◽  
Hourly Data ◽  
Cross Correlations

AbstractDue to the importance of generating energy sustainably, with the Sun being a large solar power plant for the Earth, we study the cross-correlations between the main meteorological variables (global solar radiation, air temperature, and relative air humidity) from a global cross-correlation perspective to efficiently capture solar energy. This is done initially between pairs of these variables, with the Detrended Cross-Correlation Coefficient, ρDCCA, and subsequently with the recently developed Multiple Detrended Cross-Correlation Coefficient, $${\boldsymbol{DM}}{{\boldsymbol{C}}}_{{\bf{x}}}^{{\bf{2}}}$$DMCx2. We use the hourly data from three meteorological stations of the Brazilian Institute of Meteorology located in the state of Bahia (Brazil). Initially, with the original data, we set up a color map for each variable to show the time dynamics. After, ρDCCA was calculated, thus obtaining a positive value between the global solar radiation and air temperature, and a negative value between the global solar radiation and air relative humidity, for all time scales. Finally, for the first time, was applied $${\boldsymbol{DM}}{{\boldsymbol{C}}}_{{\bf{x}}}^{{\bf{2}}}$$DMCx2 to analyze cross-correlations between three meteorological variables at the same time. On taking the global radiation as the dependent variable, and assuming that $${\boldsymbol{DM}}{{\boldsymbol{C}}}_{{\bf{x}}}^{{\bf{2}}}={\bf{1}}$$DMCx2=1 (which varies from 0 to 1) is the ideal value for the capture of solar energy, our analysis finds some patterns (differences) involving these meteorological stations with a high intensity of annual solar radiation.

scholarly journals Solar Radiation, Air Temperature, Relative Humidity, and Dew Point Study: Damak, Jhapa, Nepal

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Arun Kumar Shrestha ◽  
Arati Thapa ◽  
Hima Gautam
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Air Temperature ◽  
Gaussian Function ◽  
Great Influence ◽  
Dew Point ◽  
Upward Trend ◽  
Summer Maximum ◽  
Online Calculator ◽  
Climatic Phenomenon

Monitoring and prediction of the climatic phenomenon are of keen interest in recent years because it has great influence in the lives of people and their environments. This paper is aimed at reporting the variation of daily and monthly solar radiation, air temperature, relative humidity (RH), and dew point over the year of 2013 based on the data obtained from the weather station situated in Damak, Nepal. The result shows that on a clear day, the variation of solar radiation and RH follows the Gaussian function in which the first one has an upward trend and the second one has a downward trend. However, the change in air temperature satisfies the sine function. The dew point temperature shows somewhat complex behavior. Monthly variation of solar radiation, air temperature, and dew point shows a similar pattern, lower at winter and higher in summer. Maximum solar radiation (331 Wm-2) was observed in May and minimum (170 Wm-2) in December. Air temperature and dew point had the highest value from June to September nearly at 29°C and 25°C, respectively. The lowest value of the relative humidity (55.4%) in April indicates the driest month of the year. Dew point was also calculated from the actual readings of air temperature and relative humidity using the online calculator, and the calculated value showed the exact linear relationship with the observed value. The diurnal and nocturnal temperature of each month showed that temperature difference was relatively lower (less than 10°C) at summer rather than in winter.

The Correlations Between Acoustical Gravity Waves Caused by Solar Eclipse and the Solar Radiation

1992 ◽  
Vol 11 (2) ◽  
pp. 37-41 ◽  
Author(s):  
Jinlai Xie ◽  
Xunren Yang ◽  
Qitai Li
Keyword(s):  
Solar Radiation ◽  
Gravity Waves ◽  
Solar Eclipse ◽  
Ground Level ◽  
Atmospheric Moisture ◽  
Important Conclusion ◽  
Moisture Condition ◽  
Open Question ◽  
Annular Solar Eclipse ◽  
Abundant Data

Can solar eclipses generate AGWs? If so, how are they excited? This is still an open question and a long-standing dispute within academic circles. The annular solar eclipse which traversed the Chinese mainland on September 23rd 1987 afforded a rare and excellent opportunity to study this problem. Vast amounts of data of microbarometric pressure at ground level, radio-sondage, solar radiation and ionospheric probing were obtained from various observation stations. By making use of these abundant data synthetically, an important conclusion has been reached: there is an obvious accord between the period of the solar eclipse, AGW and the fluctuation period of solar direct radiation. All the solar eclipse AGWs in different places come from two different kinds of atmospheric oscillation, i.e., the forced oscillation generated directly by changes in direct solar radiation and the buoyancy oscillation in the local atmosphere above various spots. The former has a longer wave period and a larger amplitude, depending directly upon the radiation change during the solar eclipse; the latter has a shorter period and smaller amplitude, depending upon thermodynamic stability in the local atmosphere during the solar eclipse and the atmospheric moisture condition.

On the variation of the direct solar radiation during the annular solar eclipse of April 29, 1976

Solar Physics ◽  
1979 ◽  
Vol 62 (2) ◽  
pp. 401-405 ◽  
Author(s):  
J. Deliyannis ◽  
D. Papathanasoglou ◽  
M. Stathopoulou-Tsoga
Keyword(s):  
Solar Radiation ◽  
Solar Eclipse ◽  
Direct Solar Radiation ◽  
Annular Solar Eclipse

scholarly journals Microclimatic changes caused by different plastic coverings in greenhouses cultivated with cherry tomato in southern Brazil

2015 ◽  
Vol 30 (2) ◽  
pp. 125-133
Author(s):  
Ester Holcman ◽  
Paulo C. Sentelhas ◽  
Simone da C. Mello
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Air Temperature ◽  
Energy Availability ◽  
Plastic Film ◽  
Cherry Tomato ◽  
Growing Period ◽  
Growing Seasons ◽  
External Conditions ◽  
Intense Solar Radiation

In regions with intense solar radiation it is common the use of aluminated covers in greenhouses, with the aim of reducing the inside temperature. However, the use of these covers reduces photosynthetic active radiation (PAR) transmitted into the greenhouse. The objective of the present study was to evaluate the influence of different covers on microclimate in greenhouses cultivated with cherry tomato during three growing seasons. The environment I was covered with plastic film anti-UV and with thermo-reflective screen (40%) disposed internally. The environment II was covered with diffusive plastic film (55%). The transmitted solar radiation to the interior of covered environments was, on average, 5.5 MJ m-2 day-1 in the environment I and 8.2 MJ m-2 day-1 in environment II. The air temperature in environment II was, on average, 1°C higher than external conditions. The highest difference for the relative humidity (RH) was also observed between environment II and the outside conditions, with 10.7% for the minimum RH during the first growing period. Considering all growing periods, the diffusive plastic film provided higher solar energy availability inside the greenhouse than the plastic film with thermo-reflective screen, without causing major changes in air temperature and relative humidity, and promoting greater productivity of tomato grown under this environment for the three periods evaluated.

scholarly journals Microclimate Condition in the Natural Ventilated Greenhouse

2020 ◽  
Vol 44 (1) ◽  
pp. 31
Author(s):  
Vita Ayu Kusuma Dewi ◽  
Budi Indra Setiawan ◽  
Roh Santoso Budi Waspodo ◽  
Liyantono Liyantono
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Plant Growth ◽  
Air Temperature ◽  
Environmental Engineering ◽  
Primary Data ◽  
Climate Factors ◽  
Second Stage ◽  
Two Stages ◽  
Determining Factor

A Greenhouse has a different microclimate compared to the outside field. Climate parameters such as solar radiation and air temperature are important parameters that affect plant growth and productivity. This research aims to understand the relation of climate factors in the inside and outside Greenhouse, the effect of microclimate on evapotranspiration and to predict the amount og evapotranspiration inside the Greenhouse. Microclimate analysis was held in two stages, the firststage was from February 5 to March 21, 2018 and the second stage from March 19 to April 29, 2019 at the Department of Civil and Environmental Engineering, IPB University. Primary data was measured by the Decagon sensor. Solar radiation was collected using the Decagon PYR Pyranometer sensor and air temperature using the Decagon VP-4 sensor. Based on the result, the daily air temperature inside the Greenhouse was higher than that of the outside. The inside solar radiation was lower than that of outside the Greenhouse. The relative humidity fluctuated, and the air pressure was higher inside the Greenhouse. Evapotranspiration inside the Greenhouse was lower than outside and solar radiation was the most determining factor of evapotranspiration.

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

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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