A reflexion on the environmental effect on the transmission of COVID-19

2021 ◽  
Author(s):  
Victor L Barradas ◽  
Monica Ballinas
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Low Temperatures ◽  
Minimum Distance ◽  
Vapor Pressure Deficit ◽  
Environmental Parameters ◽  
Air Humidity ◽  
Evaporative Demand ◽  
Small Water ◽  
The Hours

<p>This research is a general reflection of the possible transmission not only of COVID-19 but of any influenza disease depending on environmental parameters such as solar radiation, air humidity and air temperature (vapor pressure deficit), evoking the Penman-Monteith model regarding the evaporation of the water that constitutes the small water droplets (aerosols) that carry the virus. In this case the evapotranspiration demand of the atmosphere with which it can be deduced that the spread of the disease will be higher in those places with less evaporative demand, that is, high air humidity and / or low temperatures, and / or low radiation intensities, and vice versa. It can also be deduced that the hours of greatest potential contagion are the night hours, while those with the lowest risk are between 2:00 p.m. and 4:00 p.m. On the other hand, in those rooms with low temperatures the contagion would be more effective. So, considering that the drops produced by a sneeze, by speaking or breathing can go beyond two meters away, it is roughly explained that the use of face masks and keeping a safe minimum distance of two meters can limit transmission of viruses and / or infections. However, this practice is not entirely safe as the environment can play an important role. What is recommended to reduce the spread of these pathogens is to produce high evaporative demands: increasing solar radiation, and increasing air temperature and reducing air humidity, which is practice that can be effective in closed rooms.</p>

scholarly journals Modeling Shoot-tip Temperature in the Greenhouse Environment

1998 ◽  
Vol 123 (2) ◽  
pp. 208-214 ◽  
Author(s):  
James E. Faust ◽  
Royal D. Heins
Keyword(s):  
Energy Balance ◽  
Solar Radiation ◽  
Air Temperature ◽  
Flower Development ◽  
Vapor Pressure Deficit ◽  
Shoot Tip ◽  
Balance Model ◽  
Glass Temperature ◽  
Air Temperatures ◽  
Material Temperature

An energy-balance model is described that predicts vinca (Catharanthus roseus L.) shoot-tip temperature using four environmental measurements: solar radiation and dry bulb, wet bulb, and glazing material temperature. The time and magnitude of the differences between shoot-tip and air temperature were determined in greenhouses maintained at air temperatures of 15, 20, 25, 30, or 35 °C. At night, shoot-tip temperature was always below air temperature. Shoot-tip temperature decreased from 0.5 to 5 °C below air temperature as greenhouse glass temperature decreased from 2 to 15 °C below air temperature. During the photoperiod under low vapor-pressure deficit (VPD) and low air temperature, shoot-tip temperature increased ≈4 °C as solar radiation increased from 0 to 600 W·m-2. Under high VPD and high air temperature, shoot-tip temperature initially decreased 1 to 2 °C at sunrise, then increased later in the morning as solar radiation increased. The model predicted shoot-tip temperatures within ±1 °C of 81% of the observed 1-hour average shoot-tip temperatures. The model was used to simulate shoot-tip temperatures under different VPD, solar radiation, and air temperatures. Since the rate of leaf and flower development are influenced by the temperature of the meristematic tissues, a model of shoot-tip temperature will be a valuable tool to predict plant development in greenhouses and to control the greenhouse environment based on a plant temperature setpoint.

Applicable Correlations Based on Field Survey and Theory for Predicting the Indoor Thermal Climate

2012 ◽  
Vol 610-613 ◽  
pp. 2819-2822
Author(s):  
Fen E Hu ◽  
Fan Wang ◽  
Neng Bang Hou ◽  
Fei Xiang Chen
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Natural Ventilation ◽  
Thermal Sensation ◽  
Environmental Parameters ◽  
Newton’S Iterative Method ◽  
Diffuse Solar Radiation ◽  
Thermal Climate ◽  
One Year ◽  
Radiant Temperature

Fanger’s PMV is the most famous thermal sensation index but it is too complex to be applied in practice. Besides, the PMV index does not take into account the effect of the hourly beam and diffuse solar radiation absorbed by the room on the indoor thermal climate. In order to obtain applicable correlations with consideration of solar radiation, a one-year measurement has been carried out in a naturally ventilated residential room in Qujing Normal University of Yunnan province, China. Based on collected data, PMV indices are calculated by using Newton’s iterative method. The correlations of the PMV and the environmental parameters — outdoor air temperature, indoor mean air temperature, mean radiant temperature, wind velocity, relative humidity, and hourly beam and diffuse solar radiation — have been studied by using the multivariable regression techniques. Lots of correlations with high correlativity have been developed in this paper. It is convenient to use these results to predict the indoor thermal climate in the natural ventilation buildings in the subtropical plateau monsoon climate.

scholarly journals Distribution features of meteorological parameters in Truong Sa archipelago area

2020 ◽  
Vol 20 (4) ◽  
pp. 405-416
Author(s):  
Le Dinh Mau ◽  
Vlasova G. A. ◽  
Demenok M. N. ◽  
Pham Sy Hoan ◽  
Nguyen Thi Thuy Dung ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Tropical Cyclones ◽  
Air Temperature ◽  
Meteorological Parameters ◽  
Southwest Monsoon ◽  
Water Evaporation ◽  
Northeast Monsoon ◽  
Air Humidity ◽  
Distribution Features ◽  
Study Results

This paper presents the distribution features of observed meteorological parameters in Truong Sa archipelago area including wind, tropical cyclone, and average values of solar radiation, air temperature, air humidity, rainfall. Observed data were collected from Truong Sa island hydro-meteorological station. In particular, data of tropical cyclones affecting Truong Sa archipelago area were collected from the websites http://www.jma.go.jp/jma/jma-eng/jma-center/(Japan). Study results show that the main meteorological parameters in Truong Sa archipelago area are affected by solar radiation and monsoonal wind regimes in East Asia region which are Northeast monsoon occurring from November to April and Southwest monsoon occurring from June to September. Transition periods are May and October. Tropical cyclones occur mainly in November–December, maximum wind speed was 64 m/s in typhoon HAIYAN (November 2013). The highest average solar radiation occurs in April (277 hours), the lowest in January (181 hours). The highest average air temperature occurs in April (29.5oC), the lowest in January (26.6oC). The highest average rainfall occurs in November (341 mm), the lowest in March (62 mm). The highest average air humidity occurs in November–December (85%), the lowest in April–May (79%). The highest average water evaporation occurs in March (129 mm), the lowest in December (87 mm).

Sensitivity of electricity consumption to air temperature, air humidity and solar radiation at the city-block scale in Osaka, Japan

2019 ◽  
Vol 45 ◽  
pp. 38-47 ◽  
Author(s):  
Yuki Hashimoto ◽  
Yukitaka Ohashi ◽  
Minako Nabeshima ◽  
Yoshinori Shigeta ◽  
Yukihiro Kikegawa ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Electricity Consumption ◽  
Air Humidity ◽  
City Block ◽  
The City

New Correlations Including Hourly Horizontal Radiation for Predicting Indoor Thermal Environment

2011 ◽  
Vol 71-78 ◽  
pp. 2671-2674
Author(s):  
Sheng Xian Wei ◽  
Shi Mei Guo ◽  
Xi Jia He
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Natural Ventilation ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Environmental Parameters ◽  
Newton’S Iterative Method ◽  
Indoor Thermal Environment ◽  
One Year ◽  
Radiant Temperature

Fanger’s PMV is the most famous thermal sensation index but it is too complex to be applied in practice. Besides, the PMV index does not include the effect of horizontal solar radiation on the indoor thermal environment. In order to obtain simple and applicable correlations with consideration of solar radiation, a one-year measurement has been conducted in a naturally ventilated residential room in Qujing Normal University of Yunnan province, China. Based on collected data, PMV indices are calculated by using Newton’s iterative method. The relationships of the PMV and the environmental parameters — outdoor air temperature, indoor mean air temperature, mean radiant temperature, wind velocity, relative humidity, and hourly horizontal solar radiation — have been studied by the multivariable regression techniques. Large numbers of correlations with high correlativity have been developed in the present paper. It is convenient to use them to evaluate and predict the indoor thermal environment in the natural ventilation buildings.

scholarly journals Projecting and Attributing Future Changes of Evaporative Demand over China in CMIP5 Climate Models

2017 ◽  
Vol 18 (4) ◽  
pp. 977-991 ◽  
Author(s):  
Wenbin Liu ◽  
Fubao Sun
Keyword(s):  
Vapor Pressure ◽  
Air Temperature ◽  
Vapor Pressure Deficit ◽  
Climate Models ◽  
Eastern China ◽  
Irrigation Scheduling ◽  
Western China ◽  
Percentage Increase ◽  
Pan Evaporation ◽  
Evaporative Demand

Abstract Atmospheric evaporative demand plays a pivotal role in global water and energy budgets, and its change is very important for drought monitoring, irrigation scheduling, and water resource management under a changing environment. Here, future changes of pan evaporation Epan, a measurable indicator for atmospheric evaporative demand, are first projected and attributed over China through a physically based approach, namely, the PenPan model, forced with outputs from 12 state-of-the-art climate models from phase 5 of the Coupled Model Intercomparison Project. An equidistant quantile mapping method was also used to correct the biases in GCMs outputs to reduce uncertainty in Epan projection. The results indicated that Epan would increase during the periods 2021–50 and 2071–2100 relative to the baseline period 1971–2000 under the representative concentration pathway (RCP) 4.5 and 8.5 scenarios, which can mainly be attributed to the projected increase in air temperature and vapor pressure deficit over China. The percentage increase of Epan is relatively larger in eastern China than in western China, which is due to the spatially inconsistent increases in air temperature, net radiation, wind speed, and vapor pressure deficit over China. The widely reported “pan evaporation paradox” was not well reproduced for the period 1961–2000 in the climate models, before or after bias correction, suggesting discrepancy between observed and modeled trends. With that caveat, it was found that the pan evaporation has been projected to increase at a rate of 117–167 mm yr−1 K−1 (72–80 mm yr−1 K−1) over China using the multiple GCMs under the RCP 4.5 (RCP 8.5) scenario with increased greenhouse gases and the associated warming of the climate system.

Indoor Thermal Comfort Predicting Correlations in Subtropical Plateau Monsoon Climate

2012 ◽  
Vol 193-194 ◽  
pp. 231-234 ◽  
Author(s):  
Sheng Xian Wei ◽  
Qing Zhou ◽  
Shu Fen Tao ◽  
Guang Xue Chen
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Sensation ◽  
Environmental Parameters ◽  
Diffuse Radiation ◽  
Monsoon Climate ◽  
Beam Radiation ◽  
Newton’S Iterative Method ◽  
Indoor Thermal Comfort

Fanger’s PMV is the most famous thermal sensation index but it is too complex to be applied in practice. Besides, the PMV index does not include the effect of hourly solar radiation on the indoor thermal climate. In order to obtain simple and applicable correlations with considerations of outdoor hourly solar radiation, a one-year measurement was performed in a naturally ventilated residential room in Qujing Normal University of Yunnan province, China. PMV indices are calculated by using Newton’s iterative method based on the collected data. Correlations of the PMV and the environmental parameters (outdoor air temperature, indoor air temperature, mean radiant temperature, wind velocity, relative humidity, hourly beam radiation and hourly diffuse radiation) have been developed by the multivariable regression technique. It is convenient to use them to predict the indoor thermal comfort in the subtropical plateau monsoon climate.

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.

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